PIC16C73A-20/P [MICROCHIP]
8-Bit CMOS Microcontrollers with A/D Converter; 8位CMOS微控制器与A / D转换器型号: | PIC16C73A-20/P |
厂家: | MICROCHIP |
描述: | 8-Bit CMOS Microcontrollers with A/D Converter |
文件: | 总288页 (文件大小:2213K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
PIC16C7X
8-Bit CMOS Microcontrollers with A/D Converter
• Wide operating voltage range: 2.5V to 6.0V
• High Sink/Source Current 25/25 mA
Devices included in this data sheet:
• PIC16C72
• PIC16C73
• PIC16C73A
• PIC16C74
• PIC16C74A
• PIC16C76
• PIC16C77
• Commercial, Industrial and Extended temperature
ranges
• Low-power consumption:
• < 2 mA @ 5V, 4 MHz
• 15 µA typical @ 3V, 32 kHz
• < 1 µA typical standby current
PIC16C7X Microcontroller Core Features:
• High-performance RISC CPU
PIC16C7X Peripheral Features:
• Only 35 single word instructions to learn
• Timer0: 8-bit timer/counter with 8-bit prescaler
• All single cycle instructions except for program
branches which are two cycle
• Timer1: 16-bit timer/counter with prescaler,
can be incremented during sleep via external
crystal/clock
• Operating speed: DC - 20 MHz clock input
DC - 200 ns instruction cycle
• Timer2: 8-bit timer/counter with 8-bit period
register, prescaler and postscaler
• Up to 8K x 14 words of Program Memory,
up to 368 x 8 bytes of Data Memory (RAM)
• Capture, Compare, PWM module(s)
• Interrupt capability
• Capture is 16-bit, max. resolution is 12.5 ns,
Compare is 16-bit, max. resolution is 200 ns,
PWM max. resolution is 10-bit
• Eight level deep hardware stack
• Direct, indirect, and relative addressing modes
• Power-on Reset (POR)
• 8-bit multichannel analog-to-digital converter
• Synchronous Serial Port (SSP) with
• Power-up Timer (PWRT) and
Oscillator Start-up Timer (OST)
2
SPI and I C
• Watchdog Timer (WDT) with its own on-chip RC
oscillator for reliable operation
• Universal Synchronous Asynchronous Receiver
Transmitter (USART/SCI)
• Programmable code-protection
• Power saving SLEEP mode
• Selectable oscillator options
• Parallel Slave Port (PSP) 8-bits wide, with
external RD, WR and CS controls
• Brown-out detection circuitry for
Brown-out Reset (BOR)
• Low-power, high-speed CMOS EPROM
technology
• Fully static design
PIC16C7X Features
72
73
73A
74
74A
76
77
Program Memory (EPROM) x 14
Data Memory (Bytes) x 8
I/O Pins
2K
128
22
—
1
4K
192
22
—
2
4K
192
22
—
2
4K
192
33
Yes
2
4K
192
33
Yes
2
8K
368
22
—
2
8K
368
33
Yes
2
Parallel Slave Port
Capture/Compare/PWM Modules
Timer Modules
3
3
3
3
3
3
3
A/D Channels
5
5
5
8
8
5
8
2
2
2
2
2
2
2
Serial Communication
SPI/I C SPI/I C, SPI/I C, SPI/I C, SPI/I C, SPI/I C, SPI/I C,
USART
USART
USART
USART
USART
USART
In-Circuit Serial Programming
Brown-out Reset
Yes
Yes
8
Yes
Yes
Yes
Yes
Yes
Yes
—
Yes
—
Yes
Yes
Yes
Interrupt Sources
11
11
12
12
11
12
1997 Microchip Technology Inc.
DS30390E-page 1
PIC16C7X
Pin Diagrams
SDIP, SOIC, Windowed Side Brazed Ceramic
SSOP
MCLR/VPP
RA0/AN0
• 1
2
28
27
26
25
24
RB7
RB6
RB5
RB4
RB3
MCLR/VPP
RA0/AN0
• 1
2
28
27
26
25
24
RB7
RB6
RB5
RB4
RB3
RA1/AN1
3
RA1/AN1
3
RA2/AN2
4
RA2/AN2
4
RA3/AN3/VREF
5
RA3/AN3/VREF
5
RA4/T0CKI
RA5/SS/AN4
VSS
6
7
8
23
22
21
RB2
RA4/T0CKI
RA5/SS/AN4
VSS
6
7
8
23
22
21
RB2
RB1
RB1
RB0/INT
RB0/INT
OSC1/CLKIN
OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI
9
20
19
18
17
16
15
VDD
OSC1/CLKIN
OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI
9
20
19
18
17
16
15
VDD
10
11
12
13
14
VSS
10
11
12
13
14
VSS
RC7
RC7
RC6
RC6
RC2/CCP1
RC5/SDO
RC4/SDI/SDA
RC2/CCP1
RC5/SDO
RC4/SDI/SDA
RC3/SCK/SCL
RC3/SCK/SCL
PIC16C72
PIC16C72
SDIP, SOIC, Windowed Side Brazed Ceramic
PDIP, Windowed CERDIP
MCLR/VPP
RA0/AN0
• 1
2
28
27
26
25
24
RB7
RB6
RB5
RB4
RB3
MCLR/VPP
RA0/AN0
1
2
3
4
5
6
7
8
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
RB7
RB6
RB5
RB4
RB3
RB2
RA1/AN1
3
RA1/AN1
RA2/AN2
RA3/AN3/VREF
RA4/T0CKI
RA2/AN2
4
RA3/AN3/VREF
5
RA4/T0CKI
RA5/SS/AN4
VSS
6
7
8
23
22
21
RB2
RA5/SS/AN4
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
VDD
RB1
RB0/INT
VDD
RB1
RB0/INT
9
10
11
12
13
14
15
16
17
18
19
20
VSS
OSC1/CLKIN
OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/CCP1
9
20
19
18
17
16
15
VDD
RD7/PSP7
RD6/PSP6
RD5/PSP5
RD4/PSP4
RC7/RX/DT
RC6/TX/CK
RC5/SDO
10
11
12
13
14
VSS
VSS
RC7/RX/DT
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
OSC1/CLKIN
OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/CCP1
RC3/SCK/SCL
RC3/SCK/SCL
RD0/PSP0
RC4/SDI/SDA
RD3/PSP3
RD2/PSP2
PIC16C73
PIC16C73A
PIC16C76
RD1/PSP1
PIC16C74
PIC16C74A
PIC16C77
DS30390E-page 2
1997 Microchip Technology Inc.
PIC16C7X
Pin Diagrams (Cont.’d)
MQFP
NC
RC7/RX/DT
RD4/PSP4
RD5/PSP5
RD6/PSP6
RD7/PSP7
VSS
VDD
RB0/INT
RB1
1
2
3
4
5
6
7
8
33
32
31
30
29
28
27
26
25
24
23
RC0/T1OSO/T1CKI
OSC2/CLKOUT
OSC1/CLKIN
VSS
VDD
PIC16C74
RE2/CS/AN7
RE1/WR/AN6
RE0/RD/AN5
RA5/SS/AN4
RA4/T0CKI
9
10
11
RB2
RB3
PLCC
MQFP
TQFP
RA4/T0CKI
RA5/SS/AN4
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
VDD
RB3
RB2
RB1
RB0/INT
VDD
7
8
9
39
38
37
36
35
34
33
32
31
30
29
NC
RC7/RX/DT
RD4/PSP4
RD5/PSP5
RD6/PSP6
RD7/PSP7
VSS
VDD
RB0/INT
RB1
1
2
3
4
5
6
7
8
9
33
32
31
30
29
28
27
26
25
24
23
RC0/T1OSO/T1CKI
OSC2/CLKOUT
OSC1/CLKIN
VSS
10
11
12
13
14
15
16
17
PIC16C74
PIC16C74A
PIC16C77
PIC16C74A
PIC16C77
VSS
VDD
VSS
RD7/PSP7
RD6/PSP6
RD5/PSP5
RD4/PSP4
RC7/RX/DT
RE2/CS/AN7
RE1/WR/AN6
RE0/RD/AN5
RA5/SS/AN4
RA4/T0CKI
OSC1/CLKIN
OSC2/CLKOUT
RC0/T1OSO/T1CKI
NC
10
11
RB2
RB3
1997 Microchip Technology Inc.
DS30390E-page 3
PIC16C7X
Table of Contents
1.0 General Description ....................................................................................................................................................................... 5
2.0 PIC16C7X Device Varieties........................................................................................................................................................... 7
3.0 Architectural Overview................................................................................................................................................................... 9
4.0 Memory Organization................................................................................................................................................................... 19
5.0 I/O Ports....................................................................................................................................................................................... 43
6.0 Overview of Timer Modules ......................................................................................................................................................... 57
7.0 Timer0 Module............................................................................................................................................................................. 59
8.0 Timer1 Module............................................................................................................................................................................. 65
9.0 Timer2 Module............................................................................................................................................................................. 69
10.0 Capture/Compare/PWM Module(s).............................................................................................................................................. 71
11.0 Synchronous Serial Port (SSP) Module....................................................................................................................................... 77
12.0 Universal Synchronous Asynchronous Receiver Transmitter (USART) ...................................................................................... 99
13.0 Analog-to-Digital Converter (A/D) Module ................................................................................................................................. 117
14.0 Special Features of the CPU ..................................................................................................................................................... 129
15.0 Instruction Set Summary............................................................................................................................................................ 147
16.0 Development Support ................................................................................................................................................................ 163
17.0 Electrical Characteristics for PIC16C72..................................................................................................................................... 167
18.0 Electrical Characteristics for PIC16C73/74................................................................................................................................ 183
19.0 Electrical Characteristics for PIC16C73A/74A........................................................................................................................... 201
20.0 Electrical Characteristics for PIC16C76/77................................................................................................................................ 219
21.0 DC and AC Characteristics Graphs and Tables ........................................................................................................................ 241
22.0 Packaging Information ............................................................................................................................................................... 251
Appendix A: ................................................................................................................................................................................... 263
Appendix B:
Appendix C:
Appendix D:
Appendix E:
Compatibility ............................................................................................................................................................. 263
What’s New............................................................................................................................................................... 264
What’s Changed ....................................................................................................................................................... 264
PIC16/17 Microcontrollers ....................................................................................................................................... 265
Pin Compatibility ................................................................................................................................................................................ 271
Index .................................................................................................................................................................................................. 273
List of Examples................................................................................................................................................................................. 279
List of Figures..................................................................................................................................................................................... 280
List of Tables...................................................................................................................................................................................... 283
Reader Response .............................................................................................................................................................................. 286
PIC16C7X Product Identification System........................................................................................................................................... 287
For register and module descriptions in this data sheet, device legends show which devices apply to those sections. As
an example, the legend below would mean that the following section applies only to the PIC16C72, PIC16C73A and
PIC16C74A devices.
Applicable Devices
72 73 73A 74 74A 76 77
To Our Valued Customers
We constantly strive to improve the quality of all our products and documentation. We have spent an exceptional
amount of time to ensure that these documents are correct. However, we realize that we may have missed a few
things. If you find any information that is missing or appears in error, please use the reader response form in the
back of this data sheet to inform us. We appreciate your assistance in making this a better document.
DS30390E-page 4
1997 Microchip Technology Inc.
PIC16C7X
8-bit A/D is provided. The 8-bit resolution is ideally
suited for applications requiring low-cost analog inter-
face, e.g. thermostat control, pressure sensing, etc.
1.0
GENERAL DESCRIPTION
The PIC16C7X is a family of low-cost, high-perfor-
mance, CMOS, fully-static, 8-bit microcontrollers with
integrated analog-to-digital (A/D) converters, in the
PIC16CXX mid-range family.
The PIC16C7X family has special features to reduce
external components, thus reducing cost, enhancing
system reliability and reducing power consumption.
There are four oscillator options, of which the single pin
RC oscillator provides a low-cost solution, the LP oscil-
lator minimizes power consumption, XT is a standard
crystal, and the HS is for High Speed crystals. The
SLEEP (power-down) feature provides a power saving
mode. The user can wake up the chip from SLEEP
through several external and internal interrupts and
resets.
All PIC16/17 microcontrollers employ an advanced
RISC architecture.The PIC16CXX microcontroller fam-
ily has enhanced core features, eight-level deep stack,
and multiple internal and external interrupt sources.
The separate instruction and data buses of the Harvard
architecture allow a 14-bit wide instruction word with
the separate 8-bit wide data. The two stage instruction
pipeline allows all instructions to execute in a single
cycle, except for program branches which require two
cycles. A total of 35 instructions (reduced instruction
set) are available. Additionally, a large register set gives
some of the architectural innovations used to achieve a
very high performance.
A highly reliable Watchdog Timer with its own on-chip
RC oscillator provides protection against software lock-
up.
A UV erasable CERDIP packaged version is ideal for
code development while the cost-effective One-Time-
Programmable (OTP) version is suitable for production
in any volume.
PIC16CXX microcontrollers typically achieve a 2:1
code compression and a 4:1 speed improvement over
other 8-bit microcontrollers in their class.
The PIC16C7X family fits perfectly in applications rang-
ing from security and remote sensors to appliance con-
trol and automotive. The EPROM technology makes
customization of application programs (transmitter
codes, motor speeds, receiver frequencies, etc.)
extremely fast and convenient. The small footprint
packages make this microcontroller series perfect for
all applications with space limitations. Low cost, low
power, high performance, ease of use and I/O flexibility
make the PIC16C7X very versatile even in areas where
no microcontroller use has been considered before
(e.g. timer functions, serial communication, capture
and compare, PWM functions and coprocessor appli-
cations).
The PIC16C72 has 128 bytes of RAM and 22 I/O pins.
In addition several peripheral features are available
including: three timer/counters, one Capture/Compare/
PWM module and one serial port. The Synchronous
Serial Port can be configured as either a 3-wire Serial
Peripheral Interface (SPI) or the two-wire Inter-Inte-
2
grated Circuit (I C) bus. Also a 5-channel high-speed
8-bit A/D is provided. The 8-bit resolution is ideally
suited for applications requiring low-cost analog inter-
face, e.g. thermostat control, pressure sensing, etc.
The PIC16C73/73A devices have 192 bytes of RAM,
while the PIC16C76 has 368 byes of RAM. Each device
has 22 I/O pins. In addition, several peripheral features
are available including: three timer/counters, two Cap-
ture/Compare/PWM modules and two serial ports. The
Synchronous Serial Port can be configured as either a
3-wire Serial Peripheral Interface (SPI) or the two-wire
1.1
Family and Upward Compatibility
Users familiar with the PIC16C5X microcontroller fam-
ily will realize that this is an enhanced version of the
PIC16C5X architecture. Please refer to Appendix A for
a detailed list of enhancements. Code written for the
PIC16C5X can be easily ported to the PIC16CXX fam-
ily of devices (Appendix B).
2
Inter-Integrated Circuit (I C) bus. The Universal Syn-
chronous
Asynchronous
Receiver
Transmitter
(USART) is also known as the Serial Communications
Interface or SCI. Also a 5-channel high-speed 8-bit A/
D is provided.The 8-bit resolution is ideally suited for
applications requiring low-cost analog interface, e.g.
thermostat control, pressure sensing, etc.
1.2
Development Support
PIC16C7X devices are supported by the complete line
of Microchip Development tools.
The PIC16C74/74A devices have 192 bytes of RAM,
while the PIC16C77 has 368 bytes of RAM. Each
device has 33 I/O pins. In addition several peripheral
features are available including: three timer/counters,
two Capture/Compare/PWM modules and two serial
ports. The Synchronous Serial Port can be configured
as either a 3-wire Serial Peripheral Interface (SPI) or
Please refer to Section 16.0 for more details about
Microchip’s development tools.
2
the two-wire Inter-Integrated Circuit (I C) bus. The Uni-
versal Synchronous Asynchronous Receiver Transmit-
ter (USART) is also known as the Serial
Communications Interface or SCI. An 8-bit Parallel
Slave Port is provided. Also an 8-channel high-speed
1997 Microchip Technology Inc.
DS30390E-page 5
PIC16C7X
TABLE 1-1:
PIC16C7XX FAMILY OF DEVCES
(1)
PIC16C710 PIC16C71 PIC16C711 PIC16C715
PIC16C72 PIC16CR72
Maximum Frequency
of Operation (MHz)
20
20
1K
—
20
1K
—
20
2K
—
20
20
Clock
EPROM Program Memory
(x14 words)
512
—
2K
—
—
Memory
ROM Program Memory
(14K words)
2K
128
Data Memory (bytes)
Timer Module(s)
36
36
68
128
128
TMR0
TMR0
TMR0
TMR0
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
Capture/Compare/
PWM Module(s)
—
—
—
—
—
—
—
—
—
1
1
Peripherals
2
2
Serial Port(s)
SPI/I C
SPI/I C
2
(SPI/I C, USART)
Parallel Slave Port
—
—
—
—
—
A/D Converter (8-bit) Channels 4
4
4
4
5
5
Interrupt Sources
I/O Pins
4
4
4
4
8
8
13
13
13
13
22
22
Voltage Range (Volts)
3.0-6.0
3.0-6.0
Yes
—
3.0-6.0
Yes
Yes
3.0-5.5
Yes
Yes
2.5-6.0
Yes
Yes
3.0-5.5
Yes
Yes
In-Circuit Serial Programming Yes
Features
Brown-out Reset
Packages
Yes
18-pin DIP, 18-pin DIP, 18-pin DIP, 18-pin DIP, 28-pin SDIP, 28-pin SDIP,
SOIC;
SOIC
SOIC;
SOIC;
SOIC, SSOP SOIC, SSOP
20-pin SSOP
20-pin SSOP 20-pin SSOP
PIC16C73A
PIC16C74A
PIC16C76
PIC16C77
Maximum Frequency of Oper- 20
ation (MHz)
20
20
20
Clock
EPROM Program Memory
(x14 words)
4K
4K
192
8K
8K
368
Memory
Data Memory (bytes)
Timer Module(s)
192
368
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
Capture/Compare/PWM Mod-
ule(s)
2
2
2
2
Peripherals
2
2
2
2
2
Serial Port(s) (SPI/I C, US- SPI/I C, USART
ART)
SPI/I C, USART
SPI/I C, USART
SPI/I C, USART
Parallel Slave Port
—
Yes
8
—
Yes
8
A/D Converter (8-bit) Channels 5
5
Interrupt Sources
I/O Pins
11
12
11
12
22
33
22
33
Voltage Range (Volts)
2.5-6.0
2.5-6.0
Yes
Yes
2.5-6.0
Yes
Yes
2.5-6.0
Yes
Yes
In-Circuit Serial Programming Yes
Features
Brown-out Reset
Packages
Yes
28-pin SDIP,
SOIC
40-pin DIP;
44-pin PLCC,
MQFP, TQFP
28-pin SDIP,
SOIC
40-pin DIP;
44-pin PLCC,
MQFP, TQFP
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capabil-
ity. All PIC16C7XX Family devices use serial programming with clock pin RB6 and data pin RB7.
Note 1: Please contact your local Microchip sales office for availability of these devices.
DS30390E-page 6
1997 Microchip Technology Inc.
PIC16C7X
2.3
Quick-Turnaround-Production (QTP)
Devices
2.0
PIC16C7X DEVICE VARIETIES
A variety of frequency ranges and packaging options
are available. Depending on application and production
requirements, the proper device option can be selected
using the information in the PIC16C7X Product Identifi-
cation System section at the end of this data sheet.
When placing orders, please use that page of the data
sheet to specify the correct part number.
Microchip offers a QTP Programming Service for fac-
tory production orders. This service is made available
for users who choose not to program a medium to high
quantity of units and whose code patterns have stabi-
lized. The devices are identical to the OTP devices but
with all EPROM locations and configuration options
already programmed by the factory. Certain code and
prototype verification procedures apply before produc-
tion shipments are available. Please contact your local
Microchip Technology sales office for more details.
For the PIC16C7X family, there are two device “types”
as indicated in the device number:
1. C, as in PIC16C74. These devices have
EPROM type memory and operate over the
standard voltage range.
2.4
Serialized Quick-Turnaround
Production (SQTPSM) Devices
2. LC, as in PIC16LC74. These devices have
EPROM type memory and operate over an
extended voltage range.
Microchip offers a unique programming service where
a few user-defined locations in each device are pro-
grammed with different serial numbers.The serial num-
bers may be random, pseudo-random, or sequential.
2.1
UV Erasable Devices
The UV erasable version, offered in CERDIP package
is optimal for prototype development and pilot
programs. This version can be erased and
reprogrammed to any of the oscillator modes.
Serial programming allows each device to have a
unique number which can serve as an entry-code,
password, or ID number.
Microchip's PICSTART Plus and PRO MATE II
programmers both support programming of the
PIC16C7X.
2.2
One-Time-Programmable (OTP)
Devices
The availability of OTP devices is especially useful for
customers who need the flexibility for frequent code
updates and small volume applications.
The OTP devices, packaged in plastic packages, per-
mit the user to program them once. In addition to the
program memory, the configuration bits must also be
programmed.
1997 Microchip Technology Inc.
DS30390E-page 7
PIC16C7X
NOTES:
DS30390E-page 8
1997 Microchip Technology Inc.
PIC16C7X
PIC16CXX devices contain an 8-bit ALU and working
register. The ALU is a general purpose arithmetic unit.
It performs arithmetic and Boolean functions between
the data in the working register and any register file.
3.0
ARCHITECTURAL OVERVIEW
The high performance of the PIC16CXX family can be
attributed to a number of architectural features com-
monly found in RISC microprocessors. To begin with,
the PIC16CXX uses a Harvard architecture, in which,
program and data are accessed from separate memo-
ries using separate buses. This improves bandwidth
over traditional von Neumann architecture in which pro-
gram and data are fetched from the same memory
using the same bus. Separating program and data
buses further allows instructions to be sized differently
than the 8-bit wide data word. Instruction opcodes are
14-bits wide making it possible to have all single word
instructions. A 14-bit wide program memory access
bus fetches a 14-bit instruction in a single cycle. A two-
stage pipeline overlaps fetch and execution of instruc-
tions (Example 3-1). Consequently, all instructions (35)
execute in a single cycle (200 ns @ 20 MHz) except for
program branches.
The ALU is 8-bits wide and capable of addition, sub-
traction, shift and logical operations. Unless otherwise
mentioned, arithmetic operations are two's comple-
ment in nature. In two-operand instructions, typically
one operand is the working register (W register). The
other operand is a file register or an immediate con-
stant. In single operand instructions, the operand is
either the W register or a file register.
The W register is an 8-bit working register used for ALU
operations. It is not an addressable register.
Depending on the instruction executed, the ALU may
affect the values of the Carry (C), Digit Carry (DC), and
Zero (Z) bits in the STATUS register.The C and DC bits
operate as a borrow bit and a digit borrow out bit,
respectively, in subtraction. See the SUBLWand SUBWF
instructions for examples.
The table below lists program memory (EPROM) and
data memory (RAM) for each PIC16C7X device.
Program
Memory
Device
Data Memory
PIC16C72
PIC16C73
PIC16C73A
PIC16C74
PIC16C74A
PIC16C76
PIC16C77
2K x 14
4K x 14
4K x 14
4K x 14
4K x 14
8K x 14
8K x 14
128 x 8
192 x 8
192 x 8
192 x 8
192 x 8
368 x 8
386 x 8
The PIC16CXX can directly or indirectly address its
register files or data memory. All special function regis-
ters, including the program counter, are mapped in the
data memory. The PIC16CXX has an orthogonal (sym-
metrical) instruction set that makes it possible to carry
out any operation on any register using any addressing
mode. This symmetrical nature and lack of ‘special
optimal situations’ make programming with the
PIC16CXX simple yet efficient. In addition, the learning
curve is reduced significantly.
1997 Microchip Technology Inc.
DS30390E-page 9
PIC16C7X
FIGURE 3-1: PIC16C72 BLOCK DIAGRAM
13
8
PORTA
Data Bus
Program Counter
EPROM
RA0/AN0
Program
Memory
RA1/AN1
RA2/AN2
RA3/AN3/VREF
RA4/T0CKI
RA5/SS/AN4
RAM
File
Registers
8 Level Stack
2K x 14
(13-bit)
128 x 8
Program
14
RAM Addr(1)
PORTB
Bus
9
Addr MUX
Instruction reg
RB0/INT
RB7:RB1
Indirect
Addr
7
Direct Addr
8
FSR reg
STATUS reg
PORTC
8
RC0/T1OSO/T1CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
3
MUX
Power-up
Timer
Oscillator
Start-up Timer
Instruction
Decode &
Control
RC6
RC7
ALU
Power-on
Reset
8
Timing
Generation
Watchdog
Timer
W reg
OSC1/CLKIN
OSC2/CLKOUT
Brown-out
Reset
MCLR VDD, VSS
Timer0
Timer1
Timer2
Synchronous
Serial Port
A/D
CCP1
Note 1: Higher order bits are from the STATUS register.
DS30390E-page 10
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 3-2: PIC16C73/73A/76 BLOCK DIAGRAM
Device
Program Memory Data Memory (RAM)
PIC16C73
PIC16C73A
PIC16C76
4K x 14
4K x 14
8K x 14
192 x 8
192 x 8
368 x 8
13
8
PORTA
Data Bus
Program Counter
RA0/AN0
RA1/AN1
EPROM
Program
Memory
RA2/AN2
RAM
File
Registers
8 Level Stack
(13-bit)
RA3/AN3/VREF
RA4/T0CKI
RA5/SS/AN4
Program
Bus
14
RAM Addr(1)
PORTB
9
Addr MUX
Instruction reg
RB0/INT
RB7:RB1
Indirect
Addr
7
Direct Addr
8
FSR reg
STATUS reg
PORTC
8
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
3
MUX
Power-up
Timer
Oscillator
Start-up Timer
Instruction
Decode &
Control
RC6/TX/CK
RC7/RX/DT
ALU
Power-on
Reset
8
Timing
Generation
Watchdog
Timer
W reg
OSC1/CLKIN
OSC2/CLKOUT
Brown-out
Reset(2)
MCLR VDD, VSS
Timer2
Timer0
CCP1
Timer1
CCP2
A/D
Synchronous
Serial Port
USART
Note 1: Higher order bits are from the STATUS register.
2: Brown-out Reset is not available on the PIC16C73.
1997 Microchip Technology Inc.
DS30390E-page 11
PIC16C7X
FIGURE 3-3: PIC16C74/74A/77 BLOCK DIAGRAM
Device
Program Memory Data Memory (RAM)
PIC16C74
PIC16C74A
PIC16C77
4K x 14
4K x 14
8K x 14
192 x 8
192 x 8
368 x 8
13
8
PORTA
Data Bus
Program Counter
RA0/AN0
RA1/AN1
EPROM
RA2/AN2
Program
Memory
RA3/AN3/VREF
RA4/T0CKI
RA5/SS/AN4
RAM
File
Registers
8 Level Stack
(13-bit)
Program
Bus
14
RAM Addr (1)
PORTB
9
Addr MUX
Instruction reg
RB0/INT
RB7:RB1
Indirect
Addr
7
Direct Addr
8
FSR reg
STATUS reg
PORTC
8
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
3
MUX
Power-up
Timer
Oscillator
Start-up Timer
Instruction
Decode &
Control
RC6/TX/CK
RC7/RX/DT
ALU
Power-on
Reset
PORTD
8
Timing
Generation
Watchdog
Timer
W reg
OSC1/CLKIN
OSC2/CLKOUT
Brown-out
Reset(2)
RD7/PSP7:RD0/PSP0
PORTE
Parallel Slave Port
MCLR VDD, VSS
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
Timer0
CCP1
Timer1
CCP2
Timer2
A/D
Synchronous
Serial Port
USART
Note 1: Higher order bits are from the STATUS register.
2: Brown-out Reset is not available on the PIC16C74.
DS30390E-page 12
1997 Microchip Technology Inc.
PIC16C7X
TABLE 3-1:
PIC16C72 PINOUT DESCRIPTION
DIP SSOP SOIC
I/O/P
Type
Buffer
Type
Pin Name
Description
Pin# Pin#
Pin#
(3)
OSC1/CLKIN
9
9
9
I
Oscillator crystal input/external clock source input.
ST/CMOS
—
OSC2/CLKOUT
10
10
10
O
Oscillator crystal output. Connects to crystal or resonator in
crystal oscillator mode. In RC mode, the OSC2 pin outputs
CLKOUT which has 1/4 the frequency of OSC1, and denotes
the instruction cycle rate.
1
1
1
I/P
ST
Master clear (reset) input or programming voltage input. This
pin is an active low reset to the device.
MCLR/VPP
PORTA is a bi-directional I/O port.
RA0 can also be analog input0
RA0/AN0
2
3
4
5
6
2
3
4
5
6
2
3
4
5
6
I/O
I/O
I/O
I/O
I/O
TTL
TTL
TTL
TTL
ST
RA1/AN1
RA1 can also be analog input1
RA2/AN2
RA2 can also be analog input2
RA3/AN3/VREF
RA4/T0CKI
RA3 can also be analog input3 or analog reference voltage
RA4 can also be the clock input to the Timer0 module.
Output is open drain type.
RA5/SS/AN4
7
7
7
I/O
TTL
RA5 can also be analog input4 or the slave select for the
synchronous serial port.
PORTB is a bi-directional I/O port. PORTB can be software
programmed for internal weak pull-up on all inputs.
(1)
RB0/INT
RB1
21
22
23
24
25
26
27
28
21
22
23
24
25
26
27
28
21
22
23
24
25
26
27
28
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
TTL/ST
TTL
RB0 can also be the external interrupt pin.
RB2
TTL
RB3
TTL
RB4
TTL
Interrupt on change pin.
RB5
TTL
Interrupt on change pin.
(2)
RB6
TTL/ST
TTL/ST
Interrupt on change pin. Serial programming clock.
Interrupt on change pin. Serial programming data.
PORTC is a bi-directional I/O port.
(2)
RB7
RC0/T1OSO/T1CKI 11
11
11
I/O
ST
RC0 can also be the Timer1 oscillator output or Timer1
clock input.
RC1/T1OSI
RC2/CCP1
12
13
12
13
12
13
I/O
I/O
ST
ST
RC1 can also be the Timer1 oscillator input.
RC2 can also be the Capture1 input/Compare1 output/
PWM1 output.
RC3/SCK/SCL
RC4/SDI/SDA
14
15
14
15
14
15
I/O
I/O
ST
ST
RC3 can also be the synchronous serial clock input/output
for both SPI and I C modes.
2
RC4 can also be the SPI Data In (SPI mode) or
2
data I/O (I C mode).
RC5/SDO
16
17
18
16
17
18
16
17
I/O
I/O
I/O
P
ST
ST
ST
—
RC5 can also be the SPI Data Out (SPI mode).
RC6
RC7
18
VSS
8, 19 8, 19
20 20
8, 19
20
Ground reference for logic and I/O pins.
Positive supply for logic and I/O pins.
VDD
P
—
Legend: I = input
O = output
— = Not used
I/O = input/output
TTL = TTL input
P = power
ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt.
2: This buffer is a Schmitt Trigger input when used in serial programming mode.
3: This buffer is a Schmitt Trigger input when configured in RC oscillator mode and a CMOS input otherwise.
1997 Microchip Technology Inc.
DS30390E-page 13
PIC16C7X
TABLE 3-2:
PIC16C73/73A/76 PINOUT DESCRIPTION
DIP
Pin#
SOIC
Pin#
I/O/P
Type
Buffer
Type
Pin Name
Description
(3)
OSC1/CLKIN
9
9
I
Oscillator crystal input/external clock source input.
ST/CMOS
—
OSC2/CLKOUT
10
10
O
Oscillator crystal output. Connects to crystal or resonator in
crystal oscillator mode. In RC mode, the OSC2 pin outputs
CLKOUT which has 1/4 the frequency of OSC1, and denotes
the instruction cycle rate.
1
1
I/P
ST
Master clear (reset) input or programming voltage input. This
pin is an active low reset to the device.
MCLR/VPP
PORTA is a bi-directional I/O port.
RA0 can also be analog input0
RA0/AN0
2
3
4
5
6
2
3
4
5
6
I/O
I/O
I/O
I/O
I/O
TTL
TTL
TTL
TTL
ST
RA1/AN1
RA1 can also be analog input1
RA2/AN2
RA2 can also be analog input2
RA3/AN3/VREF
RA4/T0CKI
RA3 can also be analog input3 or analog reference voltage
RA4 can also be the clock input to the Timer0 module.
Output is open drain type.
RA5/SS/AN4
7
7
I/O
TTL
RA5 can also be analog input4 or the slave select for the
synchronous serial port.
PORTB is a bi-directional I/O port. PORTB can be software
programmed for internal weak pull-up on all inputs.
(1)
RB0/INT
RB1
21
22
23
24
25
26
27
28
21
22
23
24
25
26
27
28
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
TTL/ST
TTL
RB0 can also be the external interrupt pin.
RB2
TTL
RB3
TTL
RB4
TTL
Interrupt on change pin.
RB5
TTL
Interrupt on change pin.
(2)
RB6
TTL/ST
TTL/ST
Interrupt on change pin. Serial programming clock.
Interrupt on change pin. Serial programming data.
PORTC is a bi-directional I/O port.
(2)
RB7
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/CCP1
11
12
13
14
15
11
12
13
14
15
I/O
I/O
I/O
I/O
I/O
ST
ST
ST
ST
ST
RC0 can also be the Timer1 oscillator output or Timer1
clock input.
RC1 can also be the Timer1 oscillator input or Capture2
input/Compare2 output/PWM2 output.
RC2 can also be the Capture1 input/Compare1 output/
PWM1 output.
RC3/SCK/SCL
RC4/SDI/SDA
RC3 can also be the synchronous serial clock input/output
2
for both SPI and I C modes.
RC4 can also be the SPI Data In (SPI mode) or
2
data I/O (I C mode).
RC5/SDO
16
17
16
17
I/O
I/O
ST
ST
RC5 can also be the SPI Data Out (SPI mode).
RC6/TX/CK
RC6 can also be the USART Asynchronous Transmit or
Synchronous Clock.
RC7/RX/DT
18
18
I/O
ST
RC7 can also be the USART Asynchronous Receive or
Synchronous Data.
VSS
8, 19
20
8, 19
20
P
P
—
—
Ground reference for logic and I/O pins.
Positive supply for logic and I/O pins.
VDD
Legend: I = input
O = output
— = Not used
I/O = input/output
TTL = TTL input
P = power
ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt.
2: This buffer is a Schmitt Trigger input when used in serial programming mode.
3: This buffer is a Schmitt Trigger input when configured in RC oscillator mode and a CMOS input otherwise.
DS30390E-page 14
1997 Microchip Technology Inc.
PIC16C7X
TABLE 3-3:
PIC16C74/74A/77 PINOUT DESCRIPTION
DIP
Pin#
PLCC
Pin#
QFP I/O/P
Pin# Type
Buffer
Type
Pin Name
Description
(4)
OSC1/CLKIN
13
14
14
15
30
31
I
ST/CMOS
—
Oscillator crystal input/external clock source input.
OSC2/CLKOUT
O
Oscillator crystal output. Connects to crystal or resonator in
crystal oscillator mode. In RC mode, OSC2 pin outputs
CLKOUT which has 1/4 the frequency of OSC1, and
denotes the instruction cycle rate.
MCLR/VPP
1
2
18
I/P
ST
Master clear (reset) input or programming voltage input.
This pin is an active low reset to the device.
PORTA is a bi-directional I/O port.
RA0 can also be analog input0
RA1 can also be analog input1
RA2 can also be analog input2
RA0/AN0
2
3
4
5
3
4
5
6
19
20
21
22
I/O
I/O
I/O
I/O
TTL
TTL
TTL
TTL
RA1/AN1
RA2/AN2
RA3/AN3/VREF
RA3 can also be analog input3 or analog reference
voltage
RA4/T0CKI
6
7
7
8
23
24
I/O
I/O
ST
RA4 can also be the clock input to the Timer0 timer/
counter. Output is open drain type.
RA5/SS/AN4
TTL
RA5 can also be analog input4 or the slave select for
the synchronous serial port.
PORTB is a bi-directional I/O port. PORTB can be software
programmed for internal weak pull-up on all inputs.
(1)
RB0/INT
RB1
33
34
35
36
37
38
39
40
36
37
38
39
41
42
43
44
8
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
TTL/ST
TTL
RB0 can also be the external interrupt pin.
9
RB2
10
11
14
15
16
17
TTL
RB3
TTL
RB4
TTL
Interrupt on change pin.
RB5
TTL
Interrupt on change pin.
(2)
RB6
TTL/ST
TTL/ST
Interrupt on change pin. Serial programming clock.
Interrupt on change pin. Serial programming data.
(2)
RB7
Legend: I = input
O = output
— = Not used
I/O = input/output
TTL = TTL input
P = power
ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as an external interrupt.
2: This buffer is a Schmitt Trigger input when used in serial programming mode.
3: This buffer is a Schmitt Trigger input when configured as general purpose I/O and a TTL input when used in the Parallel
Slave Port mode (for interfacing to a microprocessor bus).
4: This buffer is a Schmitt Trigger input when configured in RC oscillator mode and a CMOS input otherwise.
1997 Microchip Technology Inc.
DS30390E-page 15
PIC16C7X
TABLE 3-3:
PIC16C74/74A/77 PINOUT DESCRIPTION (Cont.’d)
DIP
Pin#
PLCC
Pin#
QFP I/O/P
Pin# Type
Buffer
Type
Pin Name
Description
PORTC is a bi-directional I/O port.
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/CCP1
15
16
17
18
23
24
25
26
16
18
19
20
25
26
27
29
32
35
36
37
42
43
44
1
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
ST
ST
ST
ST
ST
ST
ST
ST
RC0 can also be the Timer1 oscillator output or a
Timer1 clock input.
RC1 can also be the Timer1 oscillator input or
Capture2 input/Compare2 output/PWM2 output.
RC2 can also be the Capture1 input/Compare1 output/
PWM1 output.
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC3 can also be the synchronous serial clock input/
2
output for both SPI and I C modes.
RC4 can also be the SPI Data In (SPI mode) or
2
data I/O (I C mode).
RC5 can also be the SPI Data Out
(SPI mode).
RC6/TX/CK
RC6 can also be the USART Asynchronous Transmit or
Synchronous Clock.
RC7/RX/DT
RC7 can also be the USART Asynchronous Receive or
Synchronous Data.
PORTD is a bi-directional I/O port or parallel slave port
when interfacing to a microprocessor bus.
(3)
RD0/PSP0
RD1/PSP1
RD2/PSP2
RD3/PSP3
RD4/PSP4
RD5/PSP5
RD6/PSP6
RD7/PSP7
19
20
21
22
27
28
29
30
21
22
23
24
30
31
32
33
38
39
40
41
2
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
ST/TTL
ST/TTL
ST/TTL
ST/TTL
ST/TTL
ST/TTL
ST/TTL
ST/TTL
(3)
(3)
(3)
(3)
(3)
(3)
(3)
3
4
5
PORTE is a bi-directional I/O port.
(3)
(3)
(3)
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
8
9
9
25
26
27
I/O
I/O
I/O
ST/TTL
ST/TTL
ST/TTL
RE0 can also be read control for the parallel slave port,
or analog input5.
10
11
RE1 can also be write control for the parallel slave port,
or analog input6.
10
RE2 can also be select control for the parallel slave
port, or analog input7.
VSS
VDD
NC
12,31
11,32
—
13,34
12,35
6,29
7,28
P
P
—
—
—
Ground reference for logic and I/O pins.
Positive supply for logic and I/O pins.
1,17,28, 12,13,
40 33,34
These pins are not internally connected. These pins should
be left unconnected.
Legend: I = input
O = output
— = Not used
I/O = input/output
TTL = TTL input
P = power
ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as an external interrupt.
2: This buffer is a Schmitt Trigger input when used in serial programming mode.
3: This buffer is a Schmitt Trigger input when configured as general purpose I/O and a TTL input when used in the Parallel
Slave Port mode (for interfacing to a microprocessor bus).
4: This buffer is a Schmitt Trigger input when configured in RC oscillator mode and a CMOS input otherwise.
DS30390E-page 16
1997 Microchip Technology Inc.
PIC16C7X
3.1
Clocking Scheme/Instruction Cycle
3.2
Instruction Flow/Pipelining
The clock input (from OSC1) is internally divided by
four to generate four non-overlapping quadrature
clocks namely Q1, Q2, Q3 and Q4. Internally, the pro-
gram counter (PC) is incremented every Q1, the
instruction is fetched from the program memory and
latched into the instruction register in Q4. The instruc-
tion is decoded and executed during the following Q1
through Q4. The clocks and instruction execution flow
is shown in Figure 3-4.
An “Instruction Cycle” consists of four Q cycles (Q1,
Q2, Q3 and Q4). The instruction fetch and execute are
pipelined such that fetch takes one instruction cycle
while decode and execute takes another instruction
cycle. However, due to the pipelining, each instruction
effectively executes in one cycle. If an instruction
causes the program counter to change (e.g. GOTO)
then two cycles are required to complete the instruction
(Example 3-1).
A fetch cycle begins with the program counter (PC)
incrementing in Q1.
In the execution cycle, the fetched instruction is latched
into the “Instruction Register" (IR) in cycle Q1. This
instruction is then decoded and executed during the
Q2, Q3, and Q4 cycles. Data memory is read during Q2
(operand read) and written during Q4 (destination
write).
FIGURE 3-4: CLOCK/INSTRUCTION CYCLE
Q2
Q3
Q4
Q2
Q3
Q4
Q2
Q3
Q4
Q1
Q1
Q1
OSC1
Q1
Q2
Q3
Internal
phase
clock
Q4
PC
PC
PC+1
PC+2
OSC2/CLKOUT
(RC mode)
Fetch INST (PC)
Execute INST (PC-1)
Fetch INST (PC+1)
Execute INST (PC)
Fetch INST (PC+2)
Execute INST (PC+1)
EXAMPLE 3-1: INSTRUCTION PIPELINE FLOW
Tcy0
Tcy1
Tcy2
Tcy3
Tcy4
Tcy5
1. MOVLW 55h
Fetch 1
Execute 1
Fetch 2
2. MOVWF PORTB
3. CALL SUB_1
Execute 2
Fetch 3
Execute 3
Fetch 4
4. BSF
PORTA, BIT3 (Forced NOP)
Flush
5. Instruction @ address SUB_1
Fetch SUB_1 Execute SUB_1
All instructions are single cycle, except for any program branches. These take two cycles since the fetch
instruction is “flushed” from the pipeline while the new instruction is being fetched and then executed.
1997 Microchip Technology Inc.
DS30390E-page 17
PIC16C7X
NOTES:
DS30390E-page 18
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 4-2: PIC16C73/73A/74/74A
4.0
MEMORY ORGANIZATION
Applicable Devices
PROGRAM MEMORY MAP
AND STACK
72 73 73A 74 74A 76 77
4.1
Program Memory Organization
PC<12:0>
CALL, RETURN
RETFIE, RETLW
The PIC16C7X family has a 13-bit program counter
capable of addressing an 8K x 14 program memory
space. The amount of program memory available to
each device is listed below:
13
Stack Level 1
Program
Memory
Device
Address Range
Stack Level 8
Reset Vector
PIC16C72
PIC16C73
PIC16C73A
PIC16C74
PIC16C74A
PIC16C76
PIC16C77
2K x 14
4K x 14
4K x 14
4K x 14
4K x 14
8K x 14
8K x 14
0000h-07FFh
0000h-0FFFh
0000h-0FFFh
0000h-0FFFh
0000h-0FFFh
0000h-1FFFh
0000h-1FFFh
0000h
Interrupt Vector
0004h
0005h
On-chip Program
Memory (Page 0)
07FFh
0800h
For those devices with less than 8K program memory,
accessing a location above the physically implemented
address will cause a wraparound.
On-chip Program
Memory (Page 1)
The reset vector is at 0000h and the interrupt vector is
at 0004h.
0FFFh
1000h
FIGURE 4-1: PIC16C72 PROGRAM
MEMORY MAP AND STACK
1FFFh
PC<12:0>
CALL, RETURN
RETFIE, RETLW
13
Stack Level 1
Stack Level 8
Reset Vector
0000h
Interrupt Vector
0004h
0005h
On-chip Program
Memory
07FFh
0800h
1FFFh
1997 Microchip Technology Inc.
DS30390E-page 19
PIC16C7X
FIGURE 4-3: PIC16C76/77 PROGRAM
MEMORY MAP AND STACK
4.2
Data Memory Organization
Applicable Devices
72 73 73A 74 74A 76 77
PC<12:0>
The data memory is partitioned into multiple banks
which contain the General Purpose Registers and the
Special Function Registers. Bits RP1 and RP0 are the
bank select bits.
CALL, RETURN
RETFIE, RETLW
13
Stack Level 1
Stack Level 2
RP1:RP0 (STATUS<6:5>)
= 00 → Bank0
= 01 → Bank1
= 10 → Bank2
= 11 → Bank3
Stack Level 8
Each bank extends up to 7Fh (128 bytes). The lower
locations of each bank are reserved for the Special
Function Registers. Above the Special Function Regis-
ters are General Purpose Registers, implemented as
static RAM. All implemented banks contain special
function registers. Some “high use” special function
registers from one bank may be mirrored in another
bank for code reduction and quicker access.
Reset Vector
0000h
Interrupt Vector
0004h
0005h
On-Chip
On-Chip
Page 0
4.2.1
GENERAL PURPOSE REGISTER FILE
07FFh
0800h
The register file can be accessed either directly, or indi-
rectly through the File Select Register FSR
(Section 4.5).
Page 1
0FFFh
1000h
On-Chip
On-Chip
Page 2
Page 3
17FFh
1800h
1FFFh
DS30390E-page 20
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 4-4: PIC16C72 REGISTER FILE
MAP
FIGURE 4-5: PIC16C73/73A/74/74A
REGISTER FILE MAP
File
File
File
File
Address
Address
Address
Address
(1)
(1)
00h
01h
02h
03h
04h
05h
06h
07h
INDF
INDF
80h
81h
82h
83h
84h
85h
86h
87h
88h
89h
8Ah
8Bh
8Ch
8Dh
8Eh
8Fh
90h
91h
92h
93h
94h
95h
96h
97h
98h
99h
9Ah
9Bh
9Ch
9Dh
9Eh
9Fh
A0h
(1)
(1)
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
INDF
INDF
80h
81h
82h
83h
84h
85h
86h
87h
88h
89h
8Ah
8Bh
8Ch
8Dh
8Eh
8Fh
90h
91h
92h
93h
94h
95h
96h
97h
98h
99h
9Ah
9Bh
9Ch
9Dh
9Eh
9Fh
TMR0
PCL
OPTION
PCL
TMR0
PCL
OPTION
PCL
STATUS
FSR
STATUS
FSR
STATUS
FSR
STATUS
FSR
PORTA
PORTB
PORTC
TRISA
TRISB
TRISC
PORTA
PORTB
PORTC
TRISA
TRISB
TRISC
(2)
(2)
08h PORTD
09h PORTE
TRISD
(2)
(2)
TRISE
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
PCLATH
PCLATH
INTCON
PIE1
PCLATH
INTCON
PIR1
PCLATH
INTCON
PIE1
INTCON
PIR1
PIR2
PIE2
TMR1L
TMR1H
T1CON
TMR2
PCON
TMR1L
TMR1H
T1CON
TMR2
PCON
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
PR2
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
PR2
SSPADD
SSPSTAT
SSPADD
SSPSTAT
17h CCP1CON
17h CCP1CON
18h
19h
1Ah
1Bh
1Ch
RCSTA
TXREG
RCREG
CCPR2L
CCPR2H
TXSTA
18h
19h
1Ah
1Bh
1Ch
1Dh
SPBRG
1Dh CCP2CON
1Eh
1Fh
20h
ADRES
1Eh
1Fh
20h
ADRES
ADCON0
ADCON1
ADCON0
ADCON1
A0h
General
Purpose
Register
General
Purpose
Register
General
Purpose
Register
General
Purpose
Register
BFh
C0h
FFh
7Fh
Bank 0
Bank 1
FFh
7Fh
Bank 0
Bank 1
Unimplementeddatamemorylocations, readas
'0'.
Note 1: Not a physical register.
Unimplementeddatamemorylocations, readas
'0'.
Note 1: Not a physical register.
2: These registers are not physically imple-
mented on the PIC16C73/73A, read as '0'.
1997 Microchip Technology Inc.
DS30390E-page 21
PIC16C7X
FIGURE 4-6: PIC16C76/77 REGISTER FILE MAP
File
Address
(*)
(*)
(*)
(*)
Indirect addr.
Indirect addr.
OPTION
PCL
100h
101h
102h
103h
104h
105h
106h
107h
108h
109h
10Ah
10Bh
10Ch
10Dh
10Eh
10Fh
110h
111h
112h
113h
114h
115h
116h
117h
118h
119h
11Ah
11Bh
11Ch
11Dh
11Eh
11Fh
120h
Indirect addr.
TMR0
Indirect addr.
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
1Bh
1Ch
1Dh
1Eh
1Fh
20h
180h
181h
182h
183h
184h
185h
186h
187h
188h
189h
18Ah
18Bh
18Ch
18Dh
18Eh
18Fh
190h
191h
192h
193h
194h
195h
196h
197h
198h
199h
19Ah
19Bh
19Ch
19Dh
19Eh
19Fh
80h
81h
82h
83h
84h
85h
86h
87h
88h
89h
8Ah
8Bh
8Ch
8Dh
8Eh
8Fh
90h
91h
92h
93h
94h
95h
96h
97h
98h
99h
9Ah
9Bh
9Ch
9Dh
9Eh
9Fh
TMR0
PCL
OPTION
PCL
PCL
STATUS
FSR
STATUS
FSR
STATUS
FSR
STATUS
FSR
PORTA
PORTB
PORTC
TRISA
TRISB
TRISC
TRISB
PORTB
TRISD (1)
TRISE (1)
PORTD (1)
PORTE (1)
PCLATH
INTCON
PIR1
PCLATH
INTCON
PCLATH
INTCON
PCLATH
INTCON
PIE1
PIR2
TMR1L
PIE2
PCON
TMR1H
T1CON
TMR2
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON
PR2
SSPADD
SSPSTAT
General
Purpose
Register
General
Purpose
Register
RCSTA
TXREG
TXSTA
16 Bytes
16 Bytes
SPBRG
RCREG
CCPR2L
CCPR2H
CCP2CON
ADRES
ADCON0
ADCON1
1A0h
A0h
General
Purpose
Register
General
Purpose
Register
General
Purpose
Register
General
Purpose
Register
80 Bytes
80 Bytes
80 Bytes
1EFh
1F0h
96 Bytes
EFh
F0h
16Fh
170h
accesses
70h - 7Fh
accesses
70h-7Fh
accesses
70h-7Fh
17Fh
1FFh
7Fh
FFh
Bank 3
Bank 2
Bank 1
Bank 0
Unimplemented data memory locations, read as '0'.
* Not a physical register.
Note 1: PORTD, PORTE, TRISD, and TRISE are unimplemented on the PIC16C76, read as '0'.
Note: The upper 16 bytes of data memory in banks 1, 2, and 3 are mapped in Bank 0. This may require
relocation of data memory usage in the user application code if upgrading to the PIC16C76/77.
DS30390E-page 22
1997 Microchip Technology Inc.
PIC16C7X
4.2.2
SPECIAL FUNCTION REGISTERS
The special function registers can be classified into two
sets (core and peripheral). Those registers associated
with the “core” functions are described in this section,
and those related to the operation of the peripheral fea-
tures are described in the section of that peripheral fea-
ture.
The Special Function Registers are registers used by
the CPU and Peripheral Modules for controlling the
desired operation of the device. These registers are
implemented as static RAM.
TABLE 4-1:
PIC16C72 SPECIAL FUNCTION REGISTER SUMMARY
Value on: Value on all
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
other resets
(3)
Bank 0
00h(1)
01h
INDF
TMR0
PCL
Addressing this location uses contents of FSR to address data memory (not a physical register)
Timer0 module’s register
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
--0x 0000 --0u 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
02h(1)
03h(1)
04h(1)
05h
Program Counter's (PC) Least Significant Byte
STATUS
FSR
IRP(4)
Indirect data memory address pointer
PORTA Data Latch when written: PORTA pins when read
RP1(4)
RP0
TO
PD
Z
DC
C
PORTA
PORTB
PORTC
—
—
—
06h
PORTB Data Latch when written: PORTB pins when read
PORTC Data Latch when written: PORTC pins when read
Unimplemented
07h
08h
—
—
—
—
09h
—
Unimplemented
0Ah(1,2) PCLATH
—
GIE
—
—
—
T0IE
—
Write Buffer for the upper 5 bits of the Program Counter
---0 0000 ---0 0000
0000 000x 0000 000u
0Bh(1)
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
1Bh
1Ch
1Dh
1Eh
1Fh
INTCON
PIR1
PEIE
ADIF
INTE
—
RBIE
T0IF
INTF
RBIF
SSPIF
CCP1IF
TMR2IF
TMR1IF -0-- 0000 -0-- 0000
—
Unimplemented
—
—
TMR1L
TMR1H
T1CON
TMR2
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON
—
Holding register for the Least Significant Byte of the 16-bit TMR1 register
Holding register for the Most Significant Byte of the 16-bit TMR1 register
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
Timer2 module’s register
0000 0000 0000 0000
—
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
Synchronous Serial Port Receive Buffer/Transmit Register
WCOL SSPOV SSPEN CKP SSPM3
xxxx xxxx uuuu uuuu
SSPM0 0000 0000 0000 0000
xxxx xxxx uuuu uuuu
SSPM2
SSPM1
Capture/Compare/PWM Register (LSB)
Capture/Compare/PWM Register (MSB)
xxxx xxxx uuuu uuuu
—
—
CCP1X
CCP1Y
CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
ADRES
ADCON0
A/D Result Register
ADCS1 ADCS0
xxxx xxxx uuuu uuuu
0000 00-0 0000 00-0
CHS2
CHS1
CHS0
GO/DONE
—
ADON
Legend: x= unknown, u= unchanged, q= value depends on condition, - = unimplemented read as '0'.
Shaded locations are unimplemented, read as ‘0’.
Note 1: These registers can be addressed from either bank.
2: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose
contents are transferred to the upper byte of the program counter.
3: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset.
4: The IRP and RP1 bits are reserved on the PIC16C72, always maintain these bits clear.
1997 Microchip Technology Inc.
DS30390E-page 23
PIC16C7X
TABLE 4-1:
Address Name
Bank 1
PIC16C72 SPECIAL FUNCTION REGISTER SUMMARY (Cont.’d)
Value on: Value on all
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
other resets
(3)
80h(1)
81h
INDF
OPTION
PCL
Addressing this location uses contents of FSR to address data memory (not a physical register)
0000 0000 0000 0000
1111 1111 1111 1111
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
--11 1111 --11 1111
1111 1111 1111 1111
1111 1111 1111 1111
RBPU
Program Counter's (PC) Least Significant Byte
IRP(4) RP1(4)
RP0 TO
Indirect data memory address pointer
PORTA Data Direction Register
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
82h(1)
83h(1)
84h(1)
85h
STATUS
FSR
PD
Z
DC
C
TRISA
TRISB
TRISC
—
—
—
86h
PORTB Data Direction Register
PORTC Data Direction Register
Unimplemented
87h
88h
—
—
—
—
89h
—
Unimplemented
8Ah(1,2) PCLATH
—
GIE
—
—
—
T0IE
—
Write Buffer for the upper 5 bits of the PC
---0 0000 ---0 0000
0000 000x 0000 000u
8Bh(1)
8Ch
8Dh
8Eh
8Fh
90h
91h
92h
93h
94h
95h
96h
97h
98h
99h
9Ah
9Bh
9Ch
9Dh
9Eh
9Fh
INTCON
PEIE
ADIE
INTE
—
RBIE
T0IF
INTF
RBIF
PIE1
SSPIE
CCP1IE
TMR2IE
TMR1IE -0-- 0000 -0-- 0000
—
Unimplemented
—
—
—
PCON
—
—
—
—
—
POR
BOR
---- --qq ---- --uu
—
Unimplemented
Unimplemented
Unimplemented
—
—
—
—
—
—
—
—
PR2
Timer2 Period Register
Synchronous Serial Port (I2C mode) Address Register
1111 1111 1111 1111
0000 0000 0000 0000
--00 0000 --00 0000
SSPADD
SSPSTAT
—
—
D/A
P
S
R/W
UA
BF
—
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
ADCON1
—
—
—
—
PCFG2
PCFG1
PCFG0
---- -000 ---- -000
Legend: x= unknown, u= unchanged, q= value depends on condition, - = unimplemented read as '0'.
Shaded locations are unimplemented, read as ‘0’.
Note 1: These registers can be addressed from either bank.
2: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose
contents are transferred to the upper byte of the program counter.
3: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset.
4: The IRP and RP1 bits are reserved on the PIC16C72, always maintain these bits clear.
DS30390E-page 24
1997 Microchip Technology Inc.
PIC16C7X
TABLE 4-2:
PIC16C73/73A/74/74A SPECIAL FUNCTION REGISTER SUMMARY
Value on: Value on all
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
other resets
(2)
Bank 0
00h(4)
01h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
Timer0 module’s register
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
--0x 0000 --0u 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
---- -xxx ---- -uuu
---0 0000 ---0 0000
0000 000x 0000 000u
TMR0
PCL
02h(4)
03h(4)
04h(4)
05h
Program Counter's (PC) Least Significant Byte
STATUS
FSR
IRP(7)
Indirect data memory address pointer
PORTA Data Latch when written: PORTA pins when read
RP1(7)
RP0
TO
PD
Z
DC
C
PORTA
PORTB
PORTC
PORTD
PORTE
—
—
06h
PORTB Data Latch when written: PORTB pins when read
PORTC Data Latch when written: PORTC pins when read
PORTD Data Latch when written: PORTD pins when read
07h
08h(5)
09h(5)
—
—
—
—
—
—
—
—
RE2
RE1
RE0
0Ah(1,4) PCLATH
Write Buffer for the upper 5 bits of the Program Counter
0Bh(4)
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
1Bh
1Ch
1Dh
1Eh
1Fh
INTCON
PIR1
GIE
PEIE
ADIF
—
T0IE
RCIF
—
INTE
TXIF
–
RBIE
SSPIF
—
T0IF
CCP1IF
—
INTF
TMR2IF
—
RBIF
PSPIF(3)
—
TMR1IF 0000 0000 0000 0000
CCP2IF ---- ---0 ---- ---0
xxxx xxxx uuuu uuuu
PIR2
TMR1L
Holding register for the Least Significant Byte of the 16-bit TMR1 register
Holding register for the Most Significant Byte of the 16-bit TMR1 register
TMR1H
T1CON
TMR2
xxxx xxxx uuuu uuuu
—
—
T1CKPS1
T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
Timer2 module’s register
0000 0000 0000 0000
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON
RCSTA
—
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
Synchronous Serial Port Receive Buffer/Transmit Register
WCOL SSPOV SSPEN CKP SSPM3
xxxx xxxx uuuu uuuu
SSPM0 0000 0000 0000 0000
xxxx xxxx uuuu uuuu
SSPM2
SSPM1
Capture/Compare/PWM Register1 (LSB)
Capture/Compare/PWM Register1 (MSB)
xxxx xxxx uuuu uuuu
—
—
CCP1X
SREN
CCP1Y
CREN
CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
SPEN
RX9
—
FERR
OERR
RX9D
0000 -00x 0000 -00x
0000 0000 0000 0000
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
TXREG
RCREG
CCPR2L
CCPR2H
CCP2CON
ADRES
ADCON0
USART Transmit Data Register
USART Receive Data Register
Capture/Compare/PWM Register2 (LSB)
Capture/Compare/PWM Register2 (MSB)
—
—
CCP2X
CCP2Y
CCP2M3 CCP2M2 CCP2M1 CCP2M0 --00 0000 --00 0000
A/D Result Register
ADCS1 ADCS0
xxxx xxxx uuuu uuuu
CHS2
CHS1
CHS0
GO/DONE
—
ADON
0000 00-0 0000 00-0
Legend: x= unknown, u= unchanged, q= value depends on condition, - = unimplemented read as '0'.
Shaded locations are unimplemented, read as ‘0’.
Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose con-
tents are transferred to the upper byte of the program counter.
2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset.
3: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A, always maintain these bits clear.
4: These registers can be addressed from either bank.
5: PORTD and PORTE are not physically implemented on the PIC16C73/73A, read as ‘0’.
6: Brown-out Reset is not implemented on the PIC16C73 or the PIC16C74, read as '0'.
7: The IRP and RP1 bits are reserved on the PIC16C73/73A/74/74A, always maintain these bits clear.
1997 Microchip Technology Inc.
DS30390E-page 25
PIC16C7X
TABLE 4-2:
Address Name
Bank 1
PIC16C73/73A/74/74A SPECIAL FUNCTION REGISTER SUMMARY (Cont.’d)
Value on: Value on all
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
other resets
(2)
80h(4)
81h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
0000 0000 0000 0000
1111 1111 1111 1111
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
--11 1111 --11 1111
1111 1111 1111 1111
1111 1111 1111 1111
1111 1111 1111 1111
0000 -111 0000 -111
---0 0000 ---0 0000
0000 000x 0000 000u
OPTION
PCL
RBPU
Program Counter's (PC) Least Significant Byte
IRP(7) RP1(7)
RP0 TO
Indirect data memory address pointer
PORTA Data Direction Register
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
82h(4)
83h(4)
84h(4)
85h
STATUS
FSR
PD
Z
DC
C
TRISA
TRISB
TRISC
TRISD
TRISE
—
—
86h
PORTB Data Direction Register
PORTC Data Direction Register
PORTD Data Direction Register
87h
88h(5)
89h(5)
IBF
—
OBF
—
IBOV
—
PSPMODE
—
PORTE Data Direction Bits
8Ah(1,4) PCLATH
Write Buffer for the upper 5 bits of the Program Counter
8Bh(4)
8Ch
8Dh
8Eh
8Fh
90h
91h
92h
93h
94h
95h
96h
97h
98h
99h
9Ah
9Bh
9Ch
9Dh
9Eh
9Fh
INTCON
PIE1
PIE2
PCON
—
GIE
PEIE
ADIE
—
T0IE
RCIE
—
INTE
TXIE
—
RBIE
SSPIE
—
T0IF
CCP1IE
—
INTF
TMR2IE
—
RBIF
PSPIE(3)
—
TMR1IE 0000 0000 0000 0000
CCP2IE ---- ---0 ---- ---0
—
—
—
—
—
—
POR
BOR(6)
---- --qq ---- --uu
Unimplemented
—
—
—
—
—
—
—
Unimplemented
—
Unimplemented
PR2
SSPADD
SSPSTAT
—
Timer2 Period Register
1111 1111 1111 1111
0000 0000 0000 0000
--00 0000 --00 0000
Synchronous Serial Port (I2C mode) Address Register
—
—
D/A
P
S
R/W
UA
BF
Unimplemented
Unimplemented
Unimplemented
CSRC
—
—
—
—
—
—
—
—
TXSTA
SPBRG
—
TX9
TXEN
SYNC
—
BRGH
TRMT
TX9D
0000 -010 0000 -010
0000 0000 0000 0000
Baud Rate Generator Register
Unimplemented
—
—
—
—
—
—
—
—
—
—
—
Unimplemented
—
Unimplemented
—
Unimplemented
—
Unimplemented
ADCON1
—
—
—
—
—
PCFG2
PCFG1
PCFG0
---- -000 ---- -000
Legend: x= unknown, u= unchanged, q= value depends on condition, - = unimplemented read as '0'.
Shaded locations are unimplemented, read as ‘0’.
Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose con-
tents are transferred to the upper byte of the program counter.
2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset.
3: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A, always maintain these bits clear.
4: These registers can be addressed from either bank.
5: PORTD and PORTE are not physically implemented on the PIC16C73/73A, read as ‘0’.
6: Brown-out Reset is not implemented on the PIC16C73 or the PIC16C74, read as '0'.
7: The IRP and RP1 bits are reserved on the PIC16C73/73A/74/74A, always maintain these bits clear.
DS30390E-page 26
1997 Microchip Technology Inc.
PIC16C7X
TABLE 4-3:
PIC16C76/77 SPECIAL FUNCTION REGISTER SUMMARY
Value on: Value on all
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
other resets
(2)
Bank 0
00h(4)
01h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
Timer0 module’s register
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
--0x 0000 --0u 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
---- -xxx ---- -uuu
---0 0000 ---0 0000
0000 000x 0000 000u
TMR0
02h(4)
03h(4)
04h(4)
05h
PCL
Program Counter's (PC) Least Significant Byte
STATUS
FSR
IRP
Indirect data memory address pointer
PORTA Data Latch when written: PORTA pins when read
RP1
RP0
TO
PD
Z
DC
C
PORTA
PORTB
PORTC
PORTD
PORTE
PCLATH
INTCON
PIR1
—
—
06h
PORTB Data Latch when written: PORTB pins when read
PORTC Data Latch when written: PORTC pins when read
PORTD Data Latch when written: PORTD pins when read
07h
08h(5)
09h(5)
0Ah(1,4)
0Bh(4)
0Ch
0Dh
0Eh
—
—
—
—
—
—
—
—
RE2
RE1
RE0
Write Buffer for the upper 5 bits of the Program Counter
GIE
PEIE
ADIF
—
T0IE
RCIF
—
INTE
TXIF
–
RBIE
SSPIF
—
T0IF
CCP1IF
—
INTF
TMR2IF
—
RBIF
PSPIF(3)
—
TMR1IF 0000 0000 0000 0000
CCP2IF ---- ---0 ---- ---0
xxxx xxxx uuuu uuuu
PIR2
TMR1L
TMR1H
T1CON
TMR2
Holding register for the Least Significant Byte of the 16-bit TMR1 register
Holding register for the Most Significant Byte of the 16-bit TMR1 register
0Fh
xxxx xxxx uuuu uuuu
10h
—
—
T1CKPS1
T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
11h
Timer2 module’s register
0000 0000 0000 0000
12h
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON
RCSTA
TXREG
RCREG
CCPR2L
CCPR2H
CCP2CON
ADRES
ADCON0
—
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
13h
Synchronous Serial Port Receive Buffer/Transmit Register
WCOL SSPOV SSPEN CKP SSPM3
xxxx xxxx uuuu uuuu
SSPM0 0000 0000 0000 0000
xxxx xxxx uuuu uuuu
14h
SSPM2
SSPM1
15h
Capture/Compare/PWM Register1 (LSB)
Capture/Compare/PWM Register1 (MSB)
16h
xxxx xxxx uuuu uuuu
17h
—
—
CCP1X
SREN
CCP1Y
CREN
CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
18h
SPEN
RX9
—
FERR
OERR
RX9D
0000 -00x 0000 -00x
0000 0000 0000 0000
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
19h
USART Transmit Data Register
USART Receive Data Register
1Ah
1Bh
Capture/Compare/PWM Register2 (LSB)
Capture/Compare/PWM Register2 (MSB)
1Ch
1Dh
1Eh
—
—
CCP2X
CCP2Y
CCP2M3 CCP2M2 CCP2M1 CCP2M0 --00 0000 --00 0000
A/D Result Register
ADCS1 ADCS0
xxxx xxxx uuuu uuuu
1Fh
CHS2
CHS1
CHS0
GO/DONE
—
ADON
0000 00-0 0000 00-0
Legend: x= unknown, u= unchanged, q= value depends on condition, - = unimplemented read as '0'.
Shaded locations are unimplemented, read as ‘0’.
Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose con-
tents are transferred to the upper byte of the program counter.
2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset.
3: Bits PSPIE and PSPIF are reserved on the PIC16C76, always maintain these bits clear.
4: These registers can be addressed from any bank.
5: PORTD and PORTE are not physically implemented on the PIC16C76, read as ‘0’.
1997 Microchip Technology Inc.
DS30390E-page 27
PIC16C7X
TABLE 4-3:
Address Name
Bank 1
PIC16C76/77 SPECIAL FUNCTION REGISTER SUMMARY (Cont.’d)
Value on: Value on all
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
other resets
(2)
80h(4)
81h
INDF
OPTION
PCL
Addressing this location uses contents of FSR to address data memory (not a physical register)
0000 0000 0000 0000
1111 1111 1111 1111
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
--11 1111 --11 1111
1111 1111 1111 1111
1111 1111 1111 1111
1111 1111 1111 1111
0000 -111 0000 -111
---0 0000 ---0 0000
0000 000x 0000 000u
RBPU
Program Counter's (PC) Least Significant Byte
IRP RP1 RP0 TO
Indirect data memory address pointer
PORTA Data Direction Register
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
82h(4)
83h(4)
84h(4)
85h
STATUS
FSR
PD
Z
DC
C
TRISA
TRISB
TRISC
TRISD
TRISE
PCLATH
INTCON
PIE1
PIE2
PCON
—
—
—
86h
PORTB Data Direction Register
PORTC Data Direction Register
PORTD Data Direction Register
87h
88h(5)
89h(5)
8Ah(1,4)
8Bh(4)
8Ch
8Dh
8Eh
IBF
—
OBF
—
IBOV
—
PSPMODE
—
PORTE Data Direction Bits
Write Buffer for the upper 5 bits of the Program Counter
GIE
PEIE
ADIE
—
T0IE
RCIE
—
INTE
TXIE
—
RBIE
SSPIE
—
T0IF
CCP1IE
—
INTF
TMR2IE
—
RBIF
PSPIE(3)
—
TMR1IE 0000 0000 0000 0000
CCP2IE ---- ---0 ---- ---0
—
—
—
—
—
—
POR
BOR
---- --qq ---- --uu
8Fh
Unimplemented
—
—
—
—
—
—
90h
—
Unimplemented
91h
—
Unimplemented
92h
PR2
Timer2 Period Register
1111 1111 1111 1111
0000 0000 0000 0000
0000 0000 0000 0000
93h
SSPADD
SSPSTAT
—
Synchronous Serial Port (I2C mode) Address Register
94h
SMP
CKE
D/A
P
S
R/W
UA
BF
95h
Unimplemented
Unimplemented
Unimplemented
CSRC
—
—
—
—
—
—
96h
—
97h
—
98h
TXSTA
SPBRG
—
TX9
TXEN
SYNC
—
BRGH
TRMT
TX9D
0000 -010 0000 -010
0000 0000 0000 0000
99h
Baud Rate Generator Register
Unimplemented
9Ah
—
—
—
—
—
—
—
—
—
—
9Bh
—
Unimplemented
9Ch
9Dh
9Eh
—
Unimplemented
—
Unimplemented
—
Unimplemented
9Fh
ADCON1
—
—
—
—
—
PCFG2
PCFG1
PCFG0
---- -000 ---- -000
Legend: x= unknown, u= unchanged, q= value depends on condition, - = unimplemented read as '0'.
Shaded locations are unimplemented, read as ‘0’.
Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose con-
tents are transferred to the upper byte of the program counter.
2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset.
3: Bits PSPIE and PSPIF are reserved on the PIC16C76, always maintain these bits clear.
4: These registers can be addressed from any bank.
5: PORTD and PORTE are not physically implemented on the PIC16C76, read as ‘0’.
DS30390E-page 28
1997 Microchip Technology Inc.
PIC16C7X
TABLE 4-3:
Address Name
Bank 2
PIC16C76/77 SPECIAL FUNCTION REGISTER SUMMARY (Cont.’d)
Value on: Value on all
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
other resets
(2)
100h(4)
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
Timer0 module’s register
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
101h
TMR0
PCL
102h(4)
103h(4)
Program Counter's (PC) Least Significant Byte
STATUS
IRP
RP1
RP0
TO
PD
Z
DC
C
104h(4)
105h
106h
107h
108h
109h
FSR
—
Indirect data memory address pointer
Unimplemented
—
—
PORTB
—
PORTB Data Latch when written: PORTB pins when read
xxxx xxxx uuuu uuuu
Unimplemented
Unimplemented
Unimplemented
—
—
—
—
—
—
—
—
10Ah(1,4)
10Bh(4)
PCLATH
—
—
—
Write Buffer for the upper 5 bits of the Program Counter
INTE RBIE T0IF INTF RBIF
---0 0000 ---0 0000
0000 000x 0000 000u
INTCON
—
GIE
PEIE
T0IE
10Ch-
10Fh
Unimplemented
—
—
Bank 3
180h(4)
181h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
0000 0000 0000 0000
1111 1111 1111 1111
0000 0000 0000 0000
0001 1xxx 000q quuu
xxxx xxxx uuuu uuuu
OPTION
PCL
RBPU
Program Counter's (PC) Least Significant Byte
IRP RP1 RP0 TO
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
182h(4)
183h(4)
STATUS
PD
Z
DC
C
184h(4)
185h
186h
187h
188h
189h
FSR
—
Indirect data memory address pointer
Unimplemented
—
—
TRISB
—
PORTB Data Direction Register
Unimplemented
1111 1111 1111 1111
—
—
—
—
—
—
—
Unimplemented
—
Unimplemented
18Ah(1,4)
18Bh(4)
Write Buffer for the upper 5 bits of the Program Counter
INTE RBIE T0IF INTF RBIF
PCLATH
—
—
—
---0 0000 ---0 0000
0000 000x 0000 000u
INTCON
—
GIE
PEIE
T0IE
18Ch-
18Fh
Unimplemented
—
—
Legend: x= unknown, u= unchanged, q= value depends on condition, - = unimplemented read as '0'.
Shaded locations are unimplemented, read as ‘0’.
Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose con-
tents are transferred to the upper byte of the program counter.
2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset.
3: Bits PSPIE and PSPIF are reserved on the PIC16C76, always maintain these bits clear.
4: These registers can be addressed from any bank.
5: PORTD and PORTE are not physically implemented on the PIC16C76, read as ‘0’.
1997 Microchip Technology Inc.
DS30390E-page 29
PIC16C7X
4.2.2.1
STATUS REGISTER
For example, CLRF STATUSwill clear the upper-three
bits and set the Z bit. This leaves the STATUS register
as 000u u1uu(where u= unchanged).
Applicable Devices
72 73 73A 74 74A 76 77
It is recommended, therefore, that only BCF, BSF,
SWAPF and MOVWF instructions are used to alter the
STATUS register because these instructions do not
affect the Z, C or DC bits from the STATUS register. For
other instructions, not affecting any status bits, see the
"Instruction Set Summary."
The STATUS register, shown in Figure 4-7, contains the
arithmetic status of the ALU, the RESET status and the
bank select bits for data memory.
The STATUS register can be the destination for any
instruction, as with any other register. If the STATUS
register is the destination for an instruction that affects
the Z, DC or C bits, then the write to these three bits is
disabled. These bits are set or cleared according to the
device logic. Furthermore, the TO and PD bits are not
writable. Therefore, the result of an instruction with the
STATUS register as destination may be different than
intended.
Note 1: For those devices that do not use bits IRP
and RP1 (STATUS<7:6>), maintain these
bits clear to ensure upward compatibility
with future products.
Note 2: The C and DC bits operate as a borrow
and digit borrow bit, respectively, in sub-
traction. See the SUBLW and SUBWF
instructions for examples.
FIGURE 4-7: STATUS REGISTER (ADDRESS 03h, 83h, 103h, 183h)
R/W-0
IRP
R/W-0
RP1
R/W-0
RP0
R-1
TO
R-1
PD
R/W-x
Z
R/W-x
DC
R/W-x
C
R = Readable bit
W = Writable bit
bit7
bit0
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
IRP: Register Bank Select bit (used for indirect addressing)
1 = Bank 2, 3 (100h - 1FFh)
0 = Bank 0, 1 (00h - FFh)
bit 6-5: RP1:RP0: Register Bank Select bits (used for direct addressing)
11= Bank 3 (180h - 1FFh)
10= Bank 2 (100h - 17Fh)
01= Bank 1 (80h - FFh)
00= Bank 0 (00h - 7Fh)
Each bank is 128 bytes
bit 4:
bit 3:
bit 2:
bit 1:
bit 0:
TO: Time-out bit
1 = After power-up, CLRWDTinstruction, or SLEEPinstruction
0 = A WDT time-out occurred
PD: Power-down bit
1 = After power-up or by the CLRWDTinstruction
0 = By execution of the SLEEPinstruction
Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero
DC: Digit carry/borrow bit (ADDWF, ADDLW,SUBLW,SUBWFinstructions) (for borrow the polarity is reversed)
1 = A carry-out from the 4th low order bit of the result occurred
0 = No carry-out from the 4th low order bit of the result
C: Carry/borrow bit (ADDWF, ADDLW,SUBLW,SUBWF instructions)
1 = A carry-out from the most significant bit of the result occurred
0 = No carry-out from the most significant bit of the result occurred
Note: For borrow the polarity is reversed. A subtraction is executed by adding the two’s complement of the
second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low order bit of
the source register.
DS30390E-page 30
1997 Microchip Technology Inc.
PIC16C7X
4.2.2.2
OPTION REGISTER
Applicable Devices
72 73 73A 74 74A 76 77
Note: To achieve a 1:1 prescaler assignment for
the TMR0 register, assign the prescaler to
the Watchdog Timer.
The OPTION register is a readable and writable regis-
ter which contains various control bits to configure the
TMR0/WDT prescaler, the External INT Interrupt,
TMR0, and the weak pull-ups on PORTB.
FIGURE 4-8: OPTION REGISTER (ADDRESS 81h, 181h)
R/W-1
RBPU
R/W-1
R/W-1
T0CS
R/W-1
T0SE
R/W-1
PSA
R/W-1
PS2
R/W-1
PS1
R/W-1
PS0
INTEDG
R
= Readable bit
W = Writable bit
bit7
bit0
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
RBPU: PORTB Pull-up Enable bit
1 = PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual port latch values
bit 6:
bit 5:
bit 4:
bit 3:
INTEDG: Interrupt Edge Select bit
1 = Interrupt on rising edge of RB0/INT pin
0 = Interrupt on falling edge of RB0/INT pin
T0CS: TMR0 Clock Source Select bit
1 = Transition on RA4/T0CKI pin
0 = Internal instruction cycle clock (CLKOUT)
T0SE: TMR0 Source Edge Select bit
1 = Increment on high-to-low transition on RA4/T0CKI pin
0 = Increment on low-to-high transition on RA4/T0CKI pin
PSA: Prescaler Assignment bit
1 = Prescaler is assigned to the WDT
0 = Prescaler is assigned to the Timer0 module
bit 2-0: PS2:PS0: Prescaler Rate Select bits
Bit Value
TMR0 Rate WDT Rate
000
001
010
011
100
101
110
111
1 : 1
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
1997 Microchip Technology Inc.
DS30390E-page 31
PIC16C7X
4.2.2.3
INTCON REGISTER
Note: Interrupt flag bits get set when an interrupt
condition occurs regardless of the state of
its corresponding enable bit or the global
enable bit, GIE (INTCON<7>).
Applicable Devices
72 73 73A 74 74A 76 77
The INTCON Register is a readable and writable regis-
ter which contains various enable and flag bits for the
TMR0 register overflow, RB Port change and External
RB0/INT pin interrupts.
FIGURE 4-9: INTCON REGISTER
(ADDRESS 0Bh, 8Bh, 10Bh, 18Bh)
R/W-0
GIE
R/W-0
PEIE
R/W-0
T0IE
R/W-0
INTE
R/W-0
RBIE
R/W-0
T0IF
R/W-0
INTF
R/W-x
RBIF
R
= Readable bit
W = Writable bit
bit7
bit0
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
(1)
bit 7:
GIE: Global Interrupt Enable bit
1 = Enables all un-masked interrupts
0 = Disables all interrupts
bit 6:
bit 5:
bit 4:
bit 3:
bit 2:
bit 1:
bit 0:
PEIE: Peripheral Interrupt Enable bit
1 = Enables all un-masked peripheral interrupts
0 = Disables all peripheral interrupts
T0IE: TMR0 Overflow Interrupt Enable bit
1 = Enables the TMR0 interrupt
0 = Disables the TMR0 interrupt
INTE: RB0/INT External Interrupt Enable bit
1 = Enables the RB0/INT external interrupt
0 = Disables the RB0/INT external interrupt
RBIE: RB Port Change Interrupt Enable bit
1 = Enables the RB port change interrupt
0 = Disables the RB port change interrupt
T0IF: TMR0 Overflow Interrupt Flag bit
1 = TMR0 register has overflowed (must be cleared in software)
0 = TMR0 register did not overflow
INTF: RB0/INT External Interrupt Flag bit
1 = The RB0/INT external interrupt occurred (must be cleared in software)
0 = The RB0/INT external interrupt did not occur
RBIF: RB Port Change Interrupt Flag bit
1 = At least one of the RB7:RB4 pins changed state (must be cleared in software)
0 = None of the RB7:RB4 pins have changed state
Note 1: For the PIC16C73 and PIC16C74, if an interrupt occurs while the GIE bit is being cleared, the GIE bit
may be unintentionally re-enabled by the RETFIEinstruction in the user’s Interrupt Service Routine.
Refer to Section 14.5 for a detailed description.
Interrupt flag bits get set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the
global enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to
enabling an interrupt.
DS30390E-page 32
1997 Microchip Technology Inc.
PIC16C7X
4.2.2.4
PIE1 REGISTER
Applicable Devices
72 73 73A 74 74A 76 77
Note: Bit PEIE (INTCON<6>) must be set to
enable any peripheral interrupt.
This register contains the individual enable bits for the
peripheral interrupts.
FIGURE 4-10: PIE1 REGISTER PIC16C72 (ADDRESS 8Ch)
U-0
—
R/W-0
ADIE
U-0
—
U-0
—
R/W-0
SSPIE
R/W-0
R/W-0
TMR2IE TMR1IE
bit0
R/W-0
CCP1IE
R
= Readable bit
W = Writable bit
U
bit7
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
Unimplemented: Read as '0'
bit 6:
ADIE: A/D Converter Interrupt Enable bit
1 = Enables the A/D interrupt
0 = Disables the A/D interrupt
bit 5-4: Unimplemented: Read as '0'
bit 3:
bit 2:
bit 1:
bit 0:
SSPIE: Synchronous Serial Port Interrupt Enable bit
1 = Enables the SSP interrupt
0 = Disables the SSP interrupt
CCP1IE: CCP1 Interrupt Enable bit
1 = Enables the CCP1 interrupt
0 = Disables the CCP1 interrupt
TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
1 = Enables the TMR2 to PR2 match interrupt
0 = Disables the TMR2 to PR2 match interrupt
TMR1IE: TMR1 Overflow Interrupt Enable bit
1 = Enables the TMR1 overflow interrupt
0 = Disables the TMR1 overflow interrupt
1997 Microchip Technology Inc.
DS30390E-page 33
PIC16C7X
FIGURE 4-11: PIE1 REGISTER PIC16C73/73A/74/74A/76/77 (ADDRESS 8Ch)
R/W-0
R/W-0
ADIE
R/W-0
RCIE
R/W-0
TXIE
R/W-0
SSPIE
R/W-0
R/W-0
TMR2IE TMR1IE
bit0
R/W-0
(1)
PSPIE
bit7
CCP1IE
R
= Readable bit
W = Writable bit
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
(1)
bit 7:
PSPIE : Parallel Slave Port Read/Write Interrupt Enable bit
1 = Enables the PSP read/write interrupt
0 = Disables the PSP read/write interrupt
bit 6:
bit 5:
bit 4:
bit 3:
bit 2:
bit 1:
bit 0:
ADIE: A/D Converter Interrupt Enable bit
1 = Enables the A/D interrupt
0 = Disables the A/D interrupt
RCIE: USART Receive Interrupt Enable bit
1 = Enables the USART receive interrupt
0 = Disables the USART receive interrupt
TXIE: USART Transmit Interrupt Enable bit
1 = Enables the USART transmit interrupt
0 = Disables the USART transmit interrupt
SSPIE: Synchronous Serial Port Interrupt Enable bit
1 = Enables the SSP interrupt
0 = Disables the SSP interrupt
CCP1IE: CCP1 Interrupt Enable bit
1 = Enables the CCP1 interrupt
0 = Disables the CCP1 interrupt
TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
1 = Enables the TMR2 to PR2 match interrupt
0 = Disables the TMR2 to PR2 match interrupt
TMR1IE: TMR1 Overflow Interrupt Enable bit
1 = Enables the TMR1 overflow interrupt
0 = Disables the TMR1 overflow interrupt
Note 1: PIC16C73/73A/76 devices do not have a Parallel Slave Port implemented, this bit location is reserved
on these devices, always maintain this bit clear.
DS30390E-page 34
1997 Microchip Technology Inc.
PIC16C7X
4.2.2.5
PIR1 REGISTER
Note: Interrupt flag bits get set when an interrupt
condition occurs regardless of the state of
its corresponding enable bit or the global
enable bit, GIE (INTCON<7>). User soft-
ware should ensure the appropriate inter-
rupt flag bits are clear prior to enabling an
interrupt.
Applicable Devices
72 73 73A 74 74A 76 77
This register contains the individual flag bits for the
Peripheral interrupts.
FIGURE 4-12: PIR1 REGISTER PIC16C72 (ADDRESS 0Ch)
U-0
—
R/W-0
ADIF
U-0
—
U-0
—
R/W-0
SSPIF
R/W-0
R/W-0
TMR2IF TMR1IF
bit0
R/W-0
CCP1IF
R
= Readable bit
W = Writable bit
U
bit7
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
Unimplemented: Read as '0'
ADIF: A/D Converter Interrupt Flag bit
bit 6:
1 = An A/D conversion completed (must be cleared in software)
0 = The A/D conversion is not complete
bit 5-4: Unimplemented: Read as '0'
bit 3:
SSPIF: Synchronous Serial Port Interrupt Flag bit
1 = The transmission/reception is complete (must be cleared in software)
0 = Waiting to transmit/receive
bit 2:
CCP1IF: CCP1 Interrupt Flag bit
Capture Mode
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare Mode
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM Mode
Unused in this mode
bit 1:
bit 0:
TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
1 = TMR2 to PR2 match occurred (must be cleared in software)
0 = No TMR2 to PR2 match occurred
TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed (must be cleared in software)
0 = TMR1 register did not overflow
Interrupt flag bits get set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the
global enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to
enabling an interrupt.
1997 Microchip Technology Inc.
DS30390E-page 35
PIC16C7X
FIGURE 4-13: PIR1 REGISTER PIC16C73/73A/74/74A/76/77 (ADDRESS 0Ch)
R/W-0
R/W-0
ADIF
R-0
R-0
R/W-0
SSPIF
R/W-0
R/W-0
TMR2IF TMR1IF
bit0
R/W-0
(1)
PSPIF
bit7
RCIF
TXIF
CCP1IF
R
= Readable bit
W = Writable bit
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
PSPIF(1): Parallel Slave Port Read/Write Interrupt Flag bit
1 = A read or a write operation has taken place (must be cleared in software)
0 = No read or write has occurred
bit 6:
bit 5:
bit 4:
bit 3:
bit 2:
ADIF: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed (must be cleared in software)
0 = The A/D conversion is not complete
RCIF: USART Receive Interrupt Flag bit
1 = The USART receive buffer is full (cleared by reading RCREG)
0 = The USART receive buffer is empty
TXIF: USART Transmit Interrupt Flag bit
1 = The USART transmit buffer is empty (cleared by writing to TXREG)
0 = The USART transmit buffer is full
SSPIF: Synchronous Serial Port Interrupt Flag bit
1 = The transmission/reception is complete (must be cleared in software)
0 = Waiting to transmit/receive
CCP1IF: CCP1 Interrupt Flag bit
Capture Mode
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare Mode
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM Mode
Unused in this mode
bit 1:
bit 0:
TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
1 = TMR2 to PR2 match occurred (must be cleared in software)
0 = No TMR2 to PR2 match occurred
TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed (must be cleared in software)
0 = TMR1 register did not overflow
Note 1: PIC16C73/73A/76 devices do not have a Parallel Slave Port implemented, this bit location is reserved
on these devices, always maintain this bit clear.
Interrupt flag bits get set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the
global enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to
enabling an interrupt.
DS30390E-page 36
1997 Microchip Technology Inc.
PIC16C7X
4.2.2.6
PIE2 REGISTER
Applicable Devices
72 73 73A 74 74A 76 77
This register contains the individual enable bit for the
CCP2 peripheral interrupt.
FIGURE 4-14: PIE2 REGISTER (ADDRESS 8Dh)
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
R/W-0
CCP2IE
R
= Readable bit
W = Writable bit
bit7
bit0
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-1: Unimplemented: Read as '0'
bit 0: CCP2IE: CCP2 Interrupt Enable bit
1 = Enables the CCP2 interrupt
0 = Disables the CCP2 interrupt
1997 Microchip Technology Inc.
DS30390E-page 37
PIC16C7X
.
4.2.2.7
PIR2 REGISTER
Note: Interrupt flag bits get set when an interrupt
condition occurs regardless of the state of
its corresponding enable bit or the global
enable bit, GIE (INTCON<7>). User soft-
ware should ensure the appropriate inter-
rupt flag bits are clear prior to enabling an
interrupt.
Applicable Devices
72 73 73A 74 74A 76 77
This register contains the CCP2 interrupt flag bit.
FIGURE 4-15: PIR2 REGISTER (ADDRESS 0Dh)
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
R/W-0
CCP2IF
R
= Readable bit
W = Writable bit
bit7
bit0
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-1: Unimplemented: Read as '0'
bit 0:
CCP2IF: CCP2 Interrupt Flag bit
Capture Mode
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare Mode
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM Mode
Unused
Interrupt flag bits get set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the
global enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to
enabling an interrupt.
DS30390E-page 38
1997 Microchip Technology Inc.
PIC16C7X
4.2.2.8
PCON REGISTER
Note: BOR is unknown on Power-on Reset. It
must then be set by the user and checked
on subsequent resets to see if BOR is
clear, indicating a brown-out has occurred.
The BOR status bit is a don't care and is
not necessarily predictable if the brown-out
circuit is disabled (by clearing the BODEN
bit in the Configuration word).
Applicable Devices
72 73 73A 74 74A 76 77
The Power Control (PCON) register contains a flag bit
to allow differentiation between a Power-on Reset
(POR) to an external MCLR Reset or WDT Reset.
Those devices with brown-out detection circuitry con-
tain an additional bit to differentiate a Brown-out Reset
condition from a Power-on Reset condition.
FIGURE 4-16: PCON REGISTER (ADDRESS 8Eh)
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
R/W-0
POR
R/W-q
(1)
BOR
R
= Readable bit
W = Writable bit
bit7
bit0
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-2: Unimplemented: Read as '0'
bit 1:
POR: Power-on Reset Status bit
1 = No Power-on Reset occurred
0 = A Power-on Reset occurred (must be set in software after a Power-on Reset occurs)
bit 0:
BOR(1): Brown-out Reset Status bit
1 = No Brown-out Reset occurred
0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs)
Note 1: Brown-out Reset is not implemented on the PIC16C73/74.
1997 Microchip Technology Inc.
DS30390E-page 39
PIC16C7X
4.3
PCL and PCLATH
Applicable Devices
72 73 73A 74 74A 76 77
Note 1: There are no status bits to indicate stack
overflow or stack underflow conditions.
Note 2: There are no instructions/mnemonics
called PUSH or POP. These are actions
that occur from the execution of the
CALL, RETURN, RETLW, and RETFIE
instructions, or the vectoring to an inter-
rupt address.
The program counter (PC) is 13-bits wide.The low byte
comes from the PCL register, which is a readable and
writable register. The upper bits (PC<12:8>) are not
readable, but are indirectly writable through the
PCLATH register. On any reset, the upper bits of the
PC will be cleared. Figure 4-17 shows the two situa-
tions for the loading of the PC. The upper example in
the figure shows how the PC is loaded on a write to
PCL (PCLATH<4:0> → PCH). The lower example in
the figure shows how the PC is loaded during a CALL
or GOTOinstruction (PCLATH<4:3> → PCH).
4.4
Program Memory Paging
Applicable Devices
72 73 73A 74 74A 76 77
PIC16C7X devices are capable of addressing a contin-
uous 8K word block of program memory.TheCALLand
GOTO instructions provide only 11 bits of address to
allow branching within any 2K program memory page.
When doing a CALLor GOTOinstruction the upper 2 bits
of the address are provided by PCLATH<4:3>. When
doing a CALLor GOTOinstruction, the user must ensure
that the page select bits are programmed so that the
desired program memory page is addressed. If a return
from a CALL instruction (or interrupt) is executed, the
entire 13-bit PC is pushed onto the stack. Therefore,
manipulation of the PCLATH<4:3> bits are not required
for the return instructions (which POPs the address
from the stack).
FIGURE 4-17: LOADING OF PC IN
DIFFERENT SITUATIONS
PCH
PCL
12
8
7
0
Instruction with
PCL as
Destination
PC
8
PCLATH<4:0>
PCLATH
5
ALU
PCH
12 11 10
PCL
Note: PIC16C7X devices with 4K or less of pro-
gram memory ignore paging bit
PCLATH<4>.The use of PCLATH<4> as a
general purpose read/write bit is not rec-
ommended since this may affect upward
compatibility with future products.
8
7
0
GOTO, CALL
PC
PCLATH<4:3>
PCLATH
11
2
Opcode <10:0>
4.3.1
COMPUTED GOTO
A computed GOTO is accomplished by adding an off-
set to the program counter (ADDWF PCL). When doing
a table read using a computed GOTO method, care
should be exercised if the table location crosses a PCL
memory boundary (each 256 byte block). Refer to the
application note “Implementing a Table Read" (AN556).
4.3.2
STACK
The PIC16CXX family has an 8 level deep x 13-bit wide
hardware stack. The stack space is not part of either
program or data space and the stack pointer is not
readable or writable. The PC is PUSHed onto the stack
when a CALL instruction is executed or an interrupt
causes a branch. The stack is POPed in the event of a
RETURN, RETLW or a RETFIE instruction execution.
PCLATH is not affected by a PUSH or POP operation.
The stack operates as a circular buffer.This means that
after the stack has been PUSHed eight times, the ninth
push overwrites the value that was stored from the first
push. The tenth push overwrites the second push (and
so on).
DS30390E-page 40
1997 Microchip Technology Inc.
PIC16C7X
Example 4-1 shows the calling of a subroutine in
page 1 of the program memory.This example assumes
that PCLATH is saved and restored by the interrupt ser-
vice routine (if interrupts are used).
4.5
Indirect Addressing, INDF and FSR
Registers
Applicable Devices
72 73 73A 74 74A 76 77
The INDF register is not a physical register. Addressing
the INDF register will cause indirect addressing.
EXAMPLE 4-1: CALL OF A SUBROUTINE IN
PAGE 1 FROM PAGE 0
ORG 0x500
Indirect addressing is possible by using the INDF reg-
ister. Any instruction using the INDF register actually
accesses the register pointed to by the File Select Reg-
ister, FSR. Reading the INDF register itself indirectly
(FSR = '0') will read 00h. Writing to the INDF register
indirectly results in a no-operation (although status bits
may be affected). An effective 9-bit address is obtained
by concatenating the 8-bit FSR register and the IRP bit
(STATUS<7>), as shown in Figure 4-18.
BSF
BCF
PCLATH,3 ;Select page 1 (800h-FFFh)
PCLATH,4 ;Only on >4K devices
CALL
SUB1_P1
;Call subroutine in
;page 1 (800h-FFFh)
:
:
:
ORG 0x900
SUB1_P1:
;called subroutine
;page 1 (800h-FFFh)
:
:
A simple program to clear RAM locations 20h-2Fh
using indirect addressing is shown in Example 4-2.
RETURN
;return to Call subroutine
;in page 0 (000h-7FFh)
EXAMPLE 4-2: INDIRECT ADDRESSING
movlw 0x20
movwf FSR
;initialize pointer
;to RAM
NEXT
clrf
incf
INDF
;clear INDF register
FSR,F ;inc pointer
btfss FSR,4 ;all done?
goto
NEXT
;no clear next
CONTINUE
:
;yes continue
FIGURE 4-18: DIRECT/INDIRECT ADDRESSING
Direct Addressing
Indirect Addressing
from opcode
7
RP1:RP0
6
0
0
IRP
FSR register
bank select
location select
bank select
location select
00
01
80h
10
100h
11
00h
180h
Data
Memory
7Fh
FFh
17Fh
1FFh
Bank 0
Bank 1 Bank 2
Bank 3
For register file map detail see Figure 4-4, and Figure 4-5.
1997 Microchip Technology Inc.
DS30390E-page 41
PIC16C7X
NOTES:
DS30390E-page 42
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 5-1: BLOCK DIAGRAM OF
5.0
I/O PORTS
Applicable Devices
RA3:RA0 AND RA5 PINS
72 73 73A 74 74A 76 77
Data
bus
Some pins for these I/O ports are multiplexed with an
alternate function for the peripheral features on the
device. In general, when a peripheral is enabled, that
pin may not be used as a general purpose I/O pin.
D
Q
VDD
WR
Port
Q
Data Latch
CK
P
5.1
PORTA and TRISA Registers
Applicable Devices
I/O pin(1)
N
D
Q
72 73 73A 74 74A 76 77
WR
TRIS
PORTA is a 6-bit latch.
VSS
Analog
Q
CK
The RA4/T0CKI pin is a Schmitt Trigger input and an
open drain output. All other RA port pins have TTL input
levels and full CMOS output drivers. All pins have data
direction bits (TRIS registers) which can configure
these pins as output or input.
input
mode
TRIS Latch
TTL
RD TRIS
input
buffer
Setting a TRISA register bit puts the corresponding out-
put driver in a hi-impedance mode. Clearing a bit in the
TRISA register puts the contents of the output latch on
the selected pin(s).
Q
D
EN
Reading the PORTA register reads the status of the
pins whereas writing to it will write to the port latch. All
write operations are read-modify-write operations.
Therefore a write to a port implies that the port pins are
read, this value is modified, and then written to the port
data latch.
RD PORT
To A/D Converter
Pin RA4 is multiplexed with the Timer0 module clock
input to become the RA4/T0CKI pin.
Note 1: I/O pins have protection diodes to VDD and
VSS.
Other PORTA pins are multiplexed with analog inputs
and analog VREF input. The operation of each pin is
selected by clearing/setting the control bits in the
ADCON1 register (A/D Control Register1).
FIGURE 5-2: BLOCK DIAGRAM OF RA4/
T0CKI PIN
Note: On a Power-on Reset, these pins are con-
Data
bus
figured as analog inputs and read as '0'.
D
Q
Q
WR
PORT
The TRISA register controls the direction of the RA
pins, even when they are being used as analog inputs.
The user must ensure the bits in the TRISA register are
maintained set when using them as analog inputs.
CK
I/O pin(1)
N
Data Latch
D
Q
VSS
WR
TRIS
EXAMPLE 5-1: INITIALIZING PORTA
Schmitt
Trigger
input
Q
CK
BCF
BCF
CLRF
STATUS, RP0
STATUS, RP1 ; PIC16C76/77 only
PORTA
;
TRIS Latch
buffer
; Initialize PORTA by
; clearing output
; data latches
RD TRIS
BSF
STATUS, RP0 ; Select Bank 1
MOVLW 0xCF
; Value used to
Q
D
; initialize data
; direction
; Set RA<3:0> as inputs
; RA<5:4> as outputs
; TRISA<7:6> are always
; read as '0'.
EN
MOVWF TRISA
RD PORT
TMR0 clock input
Note 1: I/O pin has protection diodes to VSS only.
1997 Microchip Technology Inc.
DS30390E-page 43
PIC16C7X
TABLE 5-1:
Name
PORTA FUNCTIONS
Bit#
Buffer Function
RA0/AN0
bit0
bit1
bit2
bit3
bit4
TTL
TTL
TTL
TTL
ST
Input/output or analog input
RA1/AN1
Input/output or analog input
Input/output or analog input
Input/output or analog input or VREF
RA2/AN2
RA3/AN3/VREF
RA4/T0CKI
Input/output or external clock input for Timer0
Output is open drain type
RA5/SS/AN4
bit5
TTL
Input/output or slave select input for synchronous serial port or analog input
Legend: TTL = TTL input, ST = Schmitt Trigger input
TABLE 5-2:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Value on:
POR,
BOR
Value on all
other resets
Address Name
Bit 7 Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
05h
85h
9Fh
PORTA
TRISA
—
—
—
—
—
—
RA5
RA4
RA3
RA2
RA1
RA0
--0x 0000 --0u 0000
--11 1111 --11 1111
PORTA Data Direction Register
ADCON1
—
—
—
PCFG2 PCFG1 PCFG0 ---- -000 ---- -000
Legend: x= unknown, u= unchanged, -= unimplemented locations read as '0'. Shaded cells are not used by PORTA.
DS30390E-page 44
1997 Microchip Technology Inc.
PIC16C7X
Four of PORTB’s pins, RB7:RB4, have an interrupt on
change feature. Only pins configured as inputs can
cause this interrupt to occur (i.e. any RB7:RB4 pin con-
figured as an output is excluded from the interrupt on
change comparison). The input pins (of RB7:RB4) are
compared with the old value latched on the last read of
PORTB. The “mismatch” outputs of RB7:RB4 are
OR’ed together to generate the RB Port Change Inter-
rupt with flag bit RBIF (INTCON<0>).
5.2
PORTB and TRISB Registers
Applicable Devices
72 73 73A 74 74A 76 77
PORTB is an 8-bit wide bi-directional port. The corre-
sponding data direction register is TRISB. Setting a bit
in the TRISB register puts the corresponding output
driver in a hi-impedance input mode. Clearing a bit in
the TRISB register puts the contents of the output latch
on the selected pin(s).
This interrupt can wake the device from SLEEP. The
user, in the interrupt service routine, can clear the inter-
rupt in the following manner:
EXAMPLE 5-2: INITIALIZING PORTB
BCF
CLRF
STATUS, RP0
PORTB
;
; Initialize PORTB by
; clearing output
; data latches
a) Any read or write of PORTB. This will end the
mismatch condition.
b) Clear flag bit RBIF.
BSF
STATUS, RP0 ; Select Bank 1
A mismatch condition will continue to set flag bit RBIF.
Reading PORTB will end the mismatch condition, and
allow flag bit RBIF to be cleared.
MOVLW 0xCF
; Value used to
; initialize data
; direction
; Set RB<3:0> as inputs
; RB<5:4> as outputs
; RB<7:6> as inputs
MOVWF TRISB
This interrupt on mismatch feature, together with soft-
ware configurable pull-ups on these four pins allow
easy interface to a keypad and make it possible for
wake-up on key-depression. Refer to the Embedded
Control Handbook, "Implementing Wake-Up on Key
Stroke" (AN552).
Each of the PORTB pins has a weak internal pull-up. A
single control bit can turn on all the pull-ups. This is
performed by clearing bit RBPU (OPTION<7>). The
weak pull-up is automatically turned off when the port
pin is configured as an output. The pull-ups are dis-
abled on a Power-on Reset.
Note: For the PIC16C73/74, if a change on the
I/O pin should occur when the read opera-
tion is being executed (start of the Q2
cycle), then interrupt flag bit RBIF may not
get set.
FIGURE 5-3: BLOCK DIAGRAM OF
RB3:RB0 PINS
VDD
RBPU(2)
The interrupt on change feature is recommended for
wake-up on key depression operation and operations
where PORTB is only used for the interrupt on change
feature. Polling of PORTB is not recommended while
using the interrupt on change feature.
weak
P
pull-up
Data Latch
Data bus
D
Q
I/O
pin(1)
WR Port
CK
TRIS Latch
D
Q
TTL
Input
Buffer
WR TRIS
CK
RD TRIS
RD Port
Q
D
EN
RB0/INT
Schmitt Trigger
Buffer
RD Port
Note 1: I/O pins have diode protection to VDD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU bit (OPTION<7>).
1997 Microchip Technology Inc.
DS30390E-page 45
PIC16C7X
FIGURE 5-4: BLOCK DIAGRAM OF
FIGURE 5-5: BLOCK DIAGRAM OF
RB7:RB4 PINS (PIC16C72/
73A/74A/76/77)
RB7:RB4 PINS (PIC16C73/74)
VDD
RBPU(2)
VDD
weak
P
RBPU(2)
pull-up
weak
P
Data Latch
pull-up
Data bus
WR Port
D
Q
Data Latch
Data bus
I/O
pin(1)
D
Q
CK
TRIS Latch
I/O
pin(1)
WR Port
CK
TRIS Latch
D
Q
D
Q
WR TRIS
TTL
Input
Buffer
CK
WR TRIS
TTL
ST
Buffer
CK
Input
Buffer
ST
Buffer
RD TRIS
RD Port
Latch
RD TRIS
RD Port
Q
D
Latch
Q
Q
D
EN
Set RBIF
EN
Q1
Set RBIF
From other
RB7:RB4 pins
Q
D
D
From other
RB7:RB4 pins
EN
RD Port
Q3
RD Port
EN
RB7:RB6 in serial programming mode
RB7:RB6 in serial programming mode
Note 1: I/O pins have diode protection to VDD and VSS.
Note 1: I/O pins have diode protection to VDD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU bit (OPTION<7>).
2: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU bit (OPTION<7>).
TABLE 5-3:
PORTB FUNCTIONS
Name
Bit#
Buffer
Function
(1)
RB0/INT
bit0
TTL/ST
Input/output pin or external interrupt input. Internal software
programmable weak pull-up.
RB1
RB2
RB3
RB4
bit1
bit2
bit3
bit4
TTL
TTL
TTL
TTL
Input/output pin. Internal software programmable weak pull-up.
Input/output pin. Internal software programmable weak pull-up.
Input/output pin. Internal software programmable weak pull-up.
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up.
RB5
RB6
RB7
bit5
bit6
bit7
TTL
TTL/ST
TTL/ST
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up.
(2)
(2)
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up. Serial programming clock.
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up. Serial programming data.
Legend: TTL = TTL input, ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt.
2: This buffer is a Schmitt Trigger input when used in serial programming mode.
DS30390E-page 46
1997 Microchip Technology Inc.
PIC16C7X
TABLE 5-4:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Value on:
Value on all
POR,
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3 Bit 2 Bit 1 Bit 0
other resets
BOR
06h, 106h
86h, 186h
81h, 181h
PORTB
TRISB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
PS1
RB0
PS0
xxxx xxxx
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PORTB Data Direction Register
RBPU INTEDG T0CS T0SE PSA
OPTION
PS2
Legend: x= unknown, u= unchanged. Shaded cells are not used by PORTB.
1997 Microchip Technology Inc.
DS30390E-page 47
PIC16C7X
5.3
PORTC and TRISC Registers
Applicable Devices
FIGURE 5-6: PORTC BLOCK DIAGRAM
(PERIPHERAL OUTPUT
OVERRIDE)
72 73 73A 74 74A 76 77
PORTC is an 8-bit bi-directional port. Each pin is indi-
vidually configurable as an input or output through the
TRISC register. PORTC is multiplexed with several
peripheral functions (Table 5-5). PORTC pins have
Schmitt Trigger input buffers.
PORT/PERIPHERAL Select(2)
Peripheral Data Out
VDD
0
Data bus
D
Q
Q
P
WR
PORT
1
CK
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTC pin. Some
peripherals override the TRIS bit to make a pin an out-
put, while other peripherals override the TRIS bit to
make a pin an input. Since the TRIS bit override is in
effect while the peripheral is enabled, read-modify-
write instructions (BSF, BCF, XORWF) with TRISC as
destination should be avoided. The user should refer to
the corresponding peripheral section for the correct
TRIS bit settings.
Data Latch
I/O
D
Q
Q
pin(1)
WR
TRIS
CK
N
TRIS Latch
VSS
Schmitt
Trigger
RD TRIS
Peripheral
OE(3)
Q
D
EXAMPLE 5-3: INITIALIZING PORTC
EN
RD
PORT
Peripheral input
BCF
STATUS, RP0 ; Select Bank 0
BCF
STATUS, RP1 ; PIC16C76/77 only
CLRF
PORTC
; Initialize PORTC by
; clearing output
; data latches
Note 1: I/O pins have diode protection to VDD and VSS.
2: Port/Peripheral select signal selects between port
data and peripheral output.
BSF
MOVLW 0xCF
STATUS, RP0 ; Select Bank 1
3: Peripheral OE (output enable) is only activated if
peripheral select is active.
; Value used to
; initialize data
; direction
MOVWF TRISC
; Set RC<3:0> as inputs
; RC<5:4> as outputs
; RC<7:6> as inputs
TABLE 5-5:
PORTC FUNCTIONS
Name
Bit# Buffer Type
Function
bit0
bit1
RC0/T1OSO/T1CKI
ST
ST
Input/output port pin or Timer1 oscillator output/Timer1 clock input
(1)
Input/output port pin or Timer1 oscillator input or Capture2 input/
Compare2 output/PWM2 output
RC1/T1OSI/CCP2
RC2/CCP1
bit2
bit3
ST
ST
Input/output port pin or Capture1 input/Compare1 output/PWM1
output
2
RC3/SCK/SCL
RC3 can also be the synchronous serial clock for both SPI and I C
modes.
2
RC4/SDI/SDA
RC5/SDO
bit4
ST
RC4 can also be the SPI Data In (SPI mode) or data I/O (I C mode).
bit5
bit6
ST
ST
Input/output port pin or Synchronous Serial Port data output
(2)
Input/output port pin or USART Asynchronous Transmit, or USART
Synchronous Clock
RC6/TX/CK
(2)
bit7
ST
Input/output port pin or USART Asynchronous Receive, or USART
Synchronous Data
RC7/RX/DT
Legend: ST = Schmitt Trigger input
Note 1: The CCP2 multiplexed function is not enabled on the PIC16C72.
2: The TX/CK and RX/DT multiplexed functions are not enabled on the PIC16C72.
DS30390E-page 48
1997 Microchip Technology Inc.
PIC16C7X
TABLE 5-6:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
Value on:
Value on all
POR,
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
other resets
BOR
07h
87h
PORTC
TRISC
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
xxxx xxxx uuuu uuuu
1111 1111 1111 1111
PORTC Data Direction Register
Legend: x= unknown, u= unchanged.
1997 Microchip Technology Inc.
DS30390E-page 49
PIC16C7X
5.4
PORTD and TRISD Registers
Applicable Devices
FIGURE 5-7: PORTD BLOCK DIAGRAM (IN
I/O PORT MODE)
72 73 73A 74 74A 76 77
Data
bus
D
Q
PORTD is an 8-bit port with Schmitt Trigger input buff-
ers. Each pin is individually configurable as an input or
output.
WR
PORT
I/O pin(1)
CK
PORTD can be configured as an 8-bit wide micropro-
cessor port (parallel slave port) by setting control bit
PSPMODE (TRISE<4>). In this mode, the input buffers
are TTL.
Data Latch
D
Q
WR
TRIS
Schmitt
Trigger
input
CK
TRIS Latch
buffer
RD TRIS
Q
D
EN
RD PORT
Note 1: I/O pins have protection diodes to VDD and VSS.
TABLE 5-7:
Name
PORTD FUNCTIONS
Bit#
Buffer Type
Function
(1)
RD0/PSP0
RD1/PSP1
RD2/PSP2
RD3/PSP3
RD4/PSP4
RD5/PSP5
RD6/PSP6
RD7/PSP7
bit0
bit1
bit2
bit3
bit4
bit5
bit6
bit7
ST/TTL
Input/output port pin or parallel slave port bit0
(1)
ST/TTL
Input/output port pin or parallel slave port bit1
Input/output port pin or parallel slave port bit2
Input/output port pin or parallel slave port bit3
Input/output port pin or parallel slave port bit4
Input/output port pin or parallel slave port bit5
Input/output port pin or parallel slave port bit6
Input/output port pin or parallel slave port bit7
(1)
ST/TTL
(1)
ST/TTL
(1)
ST/TTL
(1)
ST/TTL
(1)
ST/TTL
(1)
ST/TTL
Legend: ST = Schmitt Trigger input TTL = TTL input
Note 1: Input buffers are Schmitt Triggers when in I/O mode and TTL buffer when in Parallel Slave Port Mode.
TABLE 5-8:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTD
Value on:
POR,
BOR
Value on all
other resets
Address Name
Bit 7 Bit 6 Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
08h
88h
89h
PORTD RD7 RD6 RD5
RD4
RD3
RD2
RD1
RD0
xxxx xxxx uuuu uuuu
1111 1111 1111 1111
0000 -111 0000 -111
TRISD PORTD Data Direction Register
TRISE IBF OBF IBOV PSPMODE
—
PORTE Data Direction Bits
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by PORTD.
DS30390E-page 50
1997 Microchip Technology Inc.
PIC16C7X
5.5
PORTE and TRISE Register
Applicable Devices
Note: On a Power-on Reset these pins are con-
figured as analog inputs.
72 73 73A 74 74A 76 77
FIGURE 5-8: PORTE BLOCK DIAGRAM (IN
I/O PORT MODE)
PORTE has three pins RE0/RD/AN5, RE1/WR/AN6
and RE2/CS/AN7, which are individually configurable
as inputs or outputs. These pins have Schmitt Trigger
input buffers.
Data
bus
D
Q
WR
PORT
I/O pin(1)
I/O PORTE becomes control inputs for the micropro-
cessor port when bit PSPMODE (TRISE<4>) is set. In
this mode, the user must make sure that the
TRISE<2:0> bits are set (pins are configured as digital
inputs) and that register ADCON1 is configured for dig-
ital I/O. In this mode the input buffers are TTL.
CK
Data Latch
D
Q
WR
TRIS
Schmitt
Trigger
input
CK
Figure 5-9 shows the TRISE register, which also con-
trols the parallel slave port operation.
TRIS Latch
buffer
PORTE pins are multiplexed with analog inputs. The
operation of these pins is selected by control bits in the
ADCON1 register. When selected as an analog input,
these pins will read as '0's.
RD TRIS
Q
D
TRISE controls the direction of the RE pins, even when
they are being used as analog inputs. The user must
make sure to keep the pins configured as inputs when
using them as analog inputs.
EN
RD PORT
Note 1: I/O pins have protection diodes to VDD and VSS.
FIGURE 5-9: TRISE REGISTER (ADDRESS 89h)
R-0
IBF
R-0
R/W-0
R/W-0
U-0
—
R/W-1
bit2
R/W-1
bit1
R/W-1
bit0
OBF
IBOV PSPMODE
R
= Readable bit
W = Writable bit
bit7
bit0
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7 :
bit 6:
bit 5:
bit 4:
IBF: Input Buffer Full Status bit
1 = A word has been received and is waiting to be read by the CPU
0 = No word has been received
OBF: Output Buffer Full Status bit
1 = The output buffer still holds a previously written word
0 = The output buffer has been read
IBOV: Input Buffer Overflow Detect bit (in microprocessor mode)
1 = A write occurred when a previously input word has not been read (must be cleared in software)
0 = No overflow occurred
PSPMODE: Parallel Slave Port Mode Select bit
1 = Parallel slave port mode
0 = General purpose I/O mode
bit 3:
bit 2:
Unimplemented: Read as '0'
PORTE Data Direction Bits
Bit2: Direction Control bit for pin RE2/CS/AN7
1 = Input
0 = Output
bit 1:
bit 0:
Bit1: Direction Control bit for pin RE1/WR/AN6
1 = Input
0 = Output
Bit0: Direction Control bit for pin RE0/RD/AN5
1 = Input
0 = Output
1997 Microchip Technology Inc.
DS30390E-page 51
PIC16C7X
TABLE 5-9:
PORTE FUNCTIONS
Name
Bit#
Buffer Type
Function
(1)
RE0/RD/AN5
bit0
ST/TTL
Input/output port pin or read control input in parallel slave port mode or
analog input:
RD
1 = Not a read operation
0 = Read operation. Reads PORTD register (if chip selected)
(1)
RE1/WR/AN6
RE2/CS/AN7
bit1
bit2
ST/TTL
Input/output port pin or write control input in parallel slave port mode or
analog input:
WR
1 = Not a write operation
0 = Write operation. Writes PORTD register (if chip selected)
(1)
ST/TTL
Input/output port pin or chip select control input in parallel slave port
mode or analog input:
CS
1 = Device is not selected
0 = Device is selected
Legend: ST = Schmitt Trigger input TTL = TTL input
Note 1: Input buffers are Schmitt Triggers when in I/O mode and TTL buffers when in Parallel Slave Port Mode.
TABLE 5-10: SUMMARY OF REGISTERS ASSOCIATED WITH PORTE
Value on:
POR,
BOR
Value on all
other resets
Address Name
Bit 7 Bit 6 Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
09h
89h
9Fh
PORTE
TRISE
—
—
—
—
—
—
—
RE2
RE1
RE0
---- -xxx ---- -uuu
0000 -111 0000 -111
---- -000 ---- -000
IBF OBF IBOV PSPMODE
PORTE Data Direction Bits
PCFG2 PCFG1 PCFG0
ADCON1
—
—
—
—
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by PORTE.
DS30390E-page 52
1997 Microchip Technology Inc.
PIC16C7X
5.6
I/O Programming Considerations
Applicable Devices
EXAMPLE 5-4: READ-MODIFY-WRITE
INSTRUCTIONS ON AN I/O
PORT
72 73 73A 74 74A 76 77
;Initial PORT settings: PORTB<7:4> Inputs
;
PORTB<3:0> Outputs
5.6.1
BI-DIRECTIONAL I/O PORTS
;PORTB<7:6> have external pull-ups and are
Any instruction which writes, operates internally as a
read followed by a write operation. The BCF and BSF
instructions, for example, read the register into the
CPU, execute the bit operation and write the result back
to the register. Caution must be used when these
instructions are applied to a port with both inputs and
outputs defined. For example, a BSFoperation on bit5
of PORTB will cause all eight bits of PORTB to be read
into the CPU. Then the BSF operation takes place on
bit5 and PORTB is written to the output latches. If
another bit of PORTB is used as a bi-directional I/O pin
(e.g., bit0) and it is defined as an input at this time, the
input signal present on the pin itself would be read into
the CPU and rewritten to the data latch of this particular
pin, overwriting the previous content. As long as the pin
stays in the input mode, no problem occurs. However, if
bit0 is switched to an output, the content of the data
latch may now be unknown.
;not connected to other circuitry
;
;
;
PORT latch PORT pins
---------- ---------
BCF PORTB, 7
BCF PORTB, 6
BSF STATUS, RP0
BCF TRISB, 7
BCF TRISB, 6
; 01pp pppp
; 10pp pppp
;
; 10pp pppp
; 10pp pppp
11pp pppp
11pp pppp
11pp pppp
10pp pppp
;
;Note that the user may have expected the
;pin values to be 00pp ppp. The 2nd BCF
;caused RB7 to be latched as the pin value
;(high).
A pin actively outputting a Low or High should not be
driven from external devices at the same time in order
to change the level on this pin (“wired-or”, “wired-and”).
The resulting high output currents may damage the
chip.
Reading the port register, reads the values of the port
pins. Writing to the port register writes the value to the
port latch. When using read-modify-write instructions
(ex. BCF, BSF, etc.) on a port, the value of the port pins
is read, the desired operation is done to this value, and
this value is then written to the port latch.
5.6.2
SUCCESSIVE OPERATIONS ON I/O PORTS
The actual write to an I/O port happens at the end of an
instruction cycle, whereas for reading, the data must be
valid at the beginning of the instruction cycle (Figure 5-
10). Therefore, care must be exercised if a write fol-
lowed by a read operation is carried out on the same I/
O port. The sequence of instructions should be such to
allow the pin voltage to stabilize (load dependent)
before the next instruction which causes that file to be
read into the CPU is executed. Otherwise, the previous
state of that pin may be read into the CPU rather than
the new state. When in doubt, it is better to separate
these instructions with a NOPor another instruction not
accessing this I/O port.
Example 5-4 shows the effect of two sequential read-
modify-write instructions on an I/O port.
FIGURE 5-10: SUCCESSIVE I/O OPERATION
Q4
Q4
Q4
Q1 Q2
Q4
Q3
Q3
Q3
Q3
Q1 Q2
PC
Q1 Q2
Q1 Q2
Note:
This example shows a write to PORTB
followed by a read from PORTB.
PC + 3
NOP
PC
Instruction
fetched
PC + 1
PC + 2
NOP
MOVWF PORTB MOVF PORTB,W
write to
PORTB
Note that:
data setup time = (0.25TCY - TPD)
RB7:RB0
where TCY = instruction cycle
TPD = propagation delay
Port pin
sampled here
TPD
Therefore, at higher clock frequencies,
a write followed by a read may be prob-
lematic.
Instruction
executed
NOP
MOVWF PORTB
write to
MOVF PORTB,W
PORTB
1997 Microchip Technology Inc.
DS30390E-page 53
PIC16C7X
5.7
Parallel Slave Port
Applicable Devices
72 73 73A 74 74A 76 77
FIGURE 5-11: PORTD AND PORTE BLOCK
DIAGRAM (PARALLEL
SLAVE PORT)
PORTD operates as an 8-bit wide Parallel Slave Port,
or microprocessor port when control bit PSPMODE
(TRISE<4>) is set. In slave mode it is asynchronously
readable and writable by the external world through RD
control input pin RE0/RD/AN5 and WR control input pin
RE1/WR/AN6.
Data bus
D
Q
WR
PORT
RDx
pin
CK
TTL
It can directly interface to an 8-bit microprocessor data
bus. The external microprocessor can read or write the
PORTD latch as an 8-bit latch. Setting bit PSPMODE
enables port pin RE0/RD/AN5 to be the RD input, RE1/
WR/AN6 to be the WR input and RE2/CS/AN7 to be the
CS (chip select) input. For this functionality, the corre-
sponding data direction bits of the TRISE register
(TRISE<2:0>) must be configured as inputs (set) and
the A/D port configuration bits PCFG2:PCFG0
(ADCON1<2:0>) must be set, which will configure pins
RE2:RE0 as digital I/O.
Q
D
RD
PORT
EN
One bit of PORTD
Set interrupt flag
PSPIF (PIR1<7>)
There are actually two 8-bit latches, one for data-out
(from the PIC16/17) and one for data input. The user
writes 8-bit data to PORTD data latch and reads data
from the port pin latch (note that they have the same
address). In this mode, the TRISD register is ignored,
since the microprocessor is controlling the direction of
data flow.
Read
RD
CS
WR
TTL
Chip Select
TTL
TTL
Write
Note: I/O pin has protection diodes to VDD and VSS.
A write to the PSP occurs when both the CS and WR
lines are first detected low. When either the CS or WR
lines become high (level triggered), then the Input
Buffer Full status flag bit IBF (TRISE<7>) is set on the
Q4 clock cycle, following the next Q2 cycle, to signal
the write is complete (Figure 5-12).The interrupt flag bit
PSPIF (PIR1<7>) is also set on the same Q4 clock
cycle. IBF can only be cleared by reading the PORTD
input latch. The input Buffer Overflow status flag bit
IBOV (TRISE<5>) is set if a second write to the Parallel
Slave Port is attempted when the previous byte has not
been read out of the buffer.
A read from the PSP occurs when both the CS and RD
lines are first detected low. The Output Buffer Full sta-
tus flag bit OBF (TRISE<6>) is cleared immediately
(Figure 5-13) indicating that the PORTD latch is waiting
to be read by the external bus. When either the CS or
RD pin becomes high (level triggered), the interrupt flag
bit PSPIF is set on the Q4 clock cycle, following the
next Q2 cycle, indicating that the read is complete.
OBF remains low until data is written to PORTD by the
user firmware.
When not in Parallel Slave Port mode, the IBF and OBF
bits are held clear. However, if flag bit IBOV was previ-
ously set, it must be cleared in firmware.
An interrupt is generated and latched into flag bit
PSPIF when a read or write operation is completed.
PSPIF must be cleared by the user in firmware and the
interrupt can be disabled by clearing the interrupt
enable bit PSPIE (PIE1<7>).
DS30390E-page 54
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 5-12: PARALLEL SLAVE PORT WRITE WAVEFORMS
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
CS
WR
RD
PORTD<7:0>
IBF
OBF
PSPIF
FIGURE 5-13: PARALLEL SLAVE PORT READ WAVEFORMS
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
CS
WR
RD
PORTD<7:0>
IBF
OBF
PSPIF
TABLE 5-11: REGISTERS ASSOCIATED WITH PARALLEL SLAVE PORT
Value on:
POR,
BOR
Value on all
other resets
Address Name
Bit 7 Bit 6 Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
08h
09h
89h
0Ch
8Ch
9Fh
PORTD
PORTE
TRISE
PIR1
Port data latch when written: Port pins when read
xxxx xxxx uuuu uuuu
---- -xxx ---- -uuu
0000 -111 0000 -111
—
—
—
—
—
RE2
RE1
RE0
IBF
OBF IBOV PSPMODE
—
PORTE Data Direction Bits
PSPIF ADIF RCIF
PSPIE ADIE RCIE
TXIF
TXIE
—
SSPIF CCP1IF TMR2IF
TMR1IF 0000 0000 0000 0000
PIE1
SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
PCFG2 PCFG1 PCFG0 ---- -000 ---- -000
ADCON1
—
—
—
—
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by the Parallel Slave Port.
1997 Microchip Technology Inc.
DS30390E-page 55
PIC16C7X
NOTES:
DS30390E-page 56
1997 Microchip Technology Inc.
PIC16C7X
CCP module, Timer1 is the time-base for 16-bit Cap-
ture or the 16-bit Compare and must be synchronized
to the device.
6.0
OVERVIEW OF TIMER
MODULES
Applicable Devices
6.3
Timer2 Overview
Applicable Devices
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
The PIC16C72, PIC16C73/73A, PIC16C74/74A,
PIC16C76/77 each have three timer modules.
Timer2 is an 8-bit timer with a programmable prescaler
and postscaler, as well as an 8-bit period register
(PR2). Timer2 can be used with the CCP1 module (in
PWM mode) as well as the Baud Rate Generator for
the Synchronous Serial Port (SSP). The prescaler
option allows Timer2 to increment at the following
rates: 1:1, 1:4, 1:16.
Each module can generate an interrupt to indicate that
an event has occurred (i.e. timer overflow). Each of
these modules is explained in full detail in the following
sections. The timer modules are:
• Timer0 Module (Section 7.0)
• Timer1 Module (Section 8.0)
• Timer2 Module (Section 9.0)
The postscaler allows the TMR2 register to match the
period register (PR2) a programmable number of times
before generating an interrupt. The postscaler can be
programmed from 1:1 to 1:16 (inclusive).
6.1
Timer0 Overview
Applicable Devices
72 73 73A 74 74A 76 77
6.4
CCP Overview
Applicable Devices
72 73 73A 74 74A 76 77
The Timer0 module is a simple 8-bit overflow counter.
The clock source can be either the internal system
clock (Fosc/4) or an external clock. When the clock
source is an external clock, the Timer0 module can be
selected to increment on either the rising or falling
edge.
The CCP module(s) can operate in one of these three
modes: 16-bit capture, 16-bit compare, or up to 10-bit
Pulse Width Modulation (PWM).
The Timer0 module also has a programmable pres-
caler option. This prescaler can be assigned to either
the Timer0 module or the Watchdog Timer. Bit PSA
(OPTION<3>) assigns the prescaler, and bits PS2:PS0
(OPTION<2:0>) determine the prescaler value. Timer0
can increment at the following rates: 1:1 (when pres-
caler assigned to Watchdog timer), 1:2, 1:4, 1:8, 1:16,
1:32, 1:64, 1:128, and 1:256 (Timer0 only).
Capture mode captures the 16-bit value of TMR1 into
the CCPRxH:CCPRxL register pair. The capture event
can be programmed for either the falling edge, rising
edge, fourth rising edge, or the sixteenth rising edge of
the CCPx pin.
Compare mode compares the TMR1H:TMR1L register
pair to the CCPRxH:CCPRxL register pair. When a
match occurs an interrupt can be generated, and the
output pin CCPx can be forced to given state (High or
Low), TMR1 can be reset (CCP1), or TMR1 reset and
start A/D conversion (CCP2).This depends on the con-
trol bits CCPxM3:CCPxM0.
Synchronization of the external clock occurs after the
prescaler. When the prescaler is used, the external
clock frequency may be higher then the device’s fre-
quency. The maximum frequency is 50 MHz, given the
high and low time requirements of the clock.
PWM mode compares the TMR2 register to a 10-bit
duty cycle register (CCPRxH:CCPRxL<5:4>) as well as
to an 8-bit period register (PR2). When the TMR2 reg-
ister = Duty Cycle register, the CCPx pin will be forced
low. When TMR2 = PR2, TMR2 is cleared to 00h, an
interrupt can be generated, and the CCPx pin (if an out-
put) will be forced high.
6.2
Timer1 Overview
Applicable Devices
72 73 73A 74 74A 76 77
Timer1 is a 16-bit timer/counter. The clock source can
be either the internal system clock (Fosc/4), an external
clock, or an external crystal. Timer1 can operate as
either a timer or a counter. When operating as a
counter (external clock source), the counter can either
operate synchronized to the device or asynchronously
to the device. Asynchronous operation allows Timer1 to
operate during sleep, which is useful for applications
that require a real-time clock as well as the power sav-
ings of SLEEP mode.
Timer1 also has a prescaler option which allows
Timer1 to increment at the following rates: 1:1, 1:2, 1:4,
and 1:8. Timer1 can be used in conjunction with the
Capture/Compare/PWM module. When used with a
1997 Microchip Technology Inc.
DS30390E-page 57
PIC16C7X
NOTES:
DS30390E-page 58
1997 Microchip Technology Inc.
PIC16C7X
Source Edge Select bit T0SE (OPTION<4>). Clearing
bit T0SE selects the rising edge. Restrictions on the
external clock input are discussed in detail in
Section 7.2.
7.0
TIMER0 MODULE
Applicable Devices
72 73 73A 74 74A 76 77
The Timer0 module timer/counter has the following fea-
tures:
The prescaler is mutually exclusively shared between
the Timer0 module and the Watchdog Timer. The pres-
caler assignment is controlled in software by control bit
PSA (OPTION<3>). Clearing bit PSA will assign the
prescaler to the Timer0 module. The prescaler is not
readable or writable. When the prescaler is assigned to
the Timer0 module, prescale values of 1:2, 1:4, ...,
1:256 are selectable. Section 7.3 details the operation
of the prescaler.
• 8-bit timer/counter
• Readable and writable
• 8-bit software programmable prescaler
• Internal or external clock select
• Interrupt on overflow from FFh to 00h
• Edge select for external clock
Figure 7-1 is a simplified block diagram of the Timer0
module.
7.1
Timer0 Interrupt
Applicable Devices
72 73 73A 74 74A 76 77
Timer mode is selected by clearing bit T0CS
(OPTION<5>). In timer mode, the Timer0 module will
increment every instruction cycle (without prescaler). If
the TMR0 register is written, the increment is inhibited
for the following two instruction cycles (Figure 7-2 and
Figure 7-3). The user can work around this by writing
an adjusted value to the TMR0 register.
The TMR0 interrupt is generated when the TMR0 reg-
ister overflows from FFh to 00h. This overflow sets bit
T0IF (INTCON<2>). The interrupt can be masked by
clearing bit T0IE (INTCON<5>). Bit T0IF must be
cleared in software by the Timer0 module interrupt ser-
vice routine before re-enabling this interrupt. The
TMR0 interrupt cannot awaken the processor from
SLEEP since the timer is shut off during SLEEP. See
Figure 7-4 for Timer0 interrupt timing.
Counter mode is selected by setting bit T0CS
(OPTION<5>). In counter mode, Timer0 will increment
either on every rising or falling edge of pin RA4/T0CKI.
The incrementing edge is determined by the Timer0
FIGURE 7-1: TIMER0 BLOCK DIAGRAM
Data bus
FOSC/4
0
1
PSout
8
1
0
Sync with
Internal
clocks
TMR0
Programmable
Prescaler
RA4/T0CKI
pin
PSout
(2 cycle delay)
T0SE
3
Set interrupt
flag bit T0IF
on overflow
PS2, PS1, PS0
PSA
T0CS
Note 1: T0CS, T0SE, PSA, PS2:PS0 (OPTION<5:0>).
2: The prescaler is shared with Watchdog Timer (refer to Figure 7-6 for detailed block diagram).
FIGURE 7-2: TIMER0 TIMING: INTERNAL CLOCK/NO PRESCALE
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC
(Program
Counter)
PC-1
PC
PC+1
PC+2
PC+3
PC+4
PC+5
PC+6
Instruction
Fetch
MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
MOVWF TMR0
T0
T0+1
T0+2
NT0
NT0
NT0
NT0+1
NT0+2
TMR0
Instruction
Executed
Read TMR0
reads NT0 + 1
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0 + 2
Write TMR0
executed
1997 Microchip Technology Inc.
DS30390E-page 59
PIC16C7X
FIGURE 7-3: TIMER0 TIMING: INTERNAL CLOCK/PRESCALE 1:2
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC
(Program
Counter)
PC-1
PC
PC+1
PC+2
PC+3
PC+4
PC+5
PC+6
MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
MOVWF TMR0
Instruction
Fetch
T0
T0+1
NT0+1
6
NT0
TMR0
Instruction
Execute
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0 + 1
Write TMR0
executed
FIGURE 7-4: TIMER0 INTERRUPT TIMING
Q1 Q2 Q3
Q4
Q1 Q2 Q3
Q4
Q1 Q2 Q3
Q4
Q1 Q2 Q3
Q4
Q1 Q2 Q3
Q4
OSC1
CLKOUT(3)
Timer0
FEh
FFh
00h
01h
02h
1
1
T0IF bit
(INTCON<2>)
GIE bit
(INTCON<7>)
INSTRUCTION
FLOW
PC
PC
PC +1
PC +1
0004h
0005h
Instruction
fetched
Inst (PC)
Inst (PC+1)
Inst (0004h)
Inst (0005h)
Instruction
executed
Inst (PC-1)
Dummy cycle
Dummy cycle
Inst (0004h)
Inst (PC)
Note 1: Interrupt flag bit T0IF is sampled here (every Q1).
2: Interrupt latency = 4Tcy where Tcy = instruction cycle time.
3: CLKOUT is available only in RC oscillator mode.
DS30390E-page 60
1997 Microchip Technology Inc.
PIC16C7X
When a prescaler is used, the external clock input is
divided by the asynchronous ripple-counter type pres-
caler so that the prescaler output is symmetrical. For
the external clock to meet the sampling requirement,
the ripple-counter must be taken into account. There-
fore, it is necessary for T0CKI to have a period of at
least 4Tosc (and a small RC delay of 40 ns) divided by
the prescaler value. The only requirement on T0CKI
high and low time is that they do not violate the mini-
mum pulse width requirement of 10 ns. Refer to param-
eters 40, 41 and 42 in the electrical specification of the
desired device.
7.2
Using Timer0 with an External Clock
Applicable Devices
72 73 73A 74 74A 76 77
When an external clock input is used for Timer0, it must
meet certain requirements. The requirements ensure
the external clock can be synchronized with the internal
phase clock (TOSC). Also, there is a delay in the actual
incrementing of Timer0 after synchronization.
7.2.1
EXTERNAL CLOCK SYNCHRONIZATION
When no prescaler is used, the external clock input is
the same as the prescaler output. The synchronization
of T0CKI with the internal phase clocks is accom-
plished by sampling the prescaler output on the Q2 and
Q4 cycles of the internal phase clocks (Figure 7-5).
Therefore, it is necessary for T0CKI to be high for at
least 2Tosc (and a small RC delay of 20 ns) and low for
at least 2Tosc (and a small RC delay of 20 ns). Refer to
the electrical specification of the desired device.
7.2.2
TMR0 INCREMENT DELAY
Since the prescaler output is synchronized with the
internal clocks, there is a small delay from the time the
external clock edge occurs to the time the Timer0 mod-
ule is actually incremented. Figure 7-5 shows the delay
from the external clock edge to the timer incrementing.
FIGURE 7-5: TIMER0 TIMING WITH EXTERNAL CLOCK
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Small pulse
misses sampling
External Clock Input or
(2)
Prescaler output
(1)
(3)
External Clock/Prescaler
Output after sampling
Increment Timer0 (Q4)
Timer0
T0
T0 + 1
T0 + 2
Note 1: Delay from clock input change to Timer0 increment is 3Tosc to 7Tosc. (Duration of Q = Tosc).
Therefore, the error in measuring the interval between two edges on Timer0 input = ±4Tosc max.
2: External clock if no prescaler selected, Prescaler output otherwise.
3: The arrows indicate the points in time where sampling occurs.
1997 Microchip Technology Inc.
DS30390E-page 61
PIC16C7X
The PSA and PS2:PS0 bits (OPTION<3:0>) determine
the prescaler assignment and prescale ratio.
7.3
Prescaler
Applicable Devices
72 73 73A 74 74A 76 77
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g.CLRF 1, MOVWF 1,
An 8-bit counter is available as a prescaler for the
Timer0 module, or as a postscaler for the Watchdog
Timer, respectively (Figure 7-6). For simplicity, this
counter is being referred to as “prescaler” throughout
this data sheet. Note that there is only one prescaler
available which is mutually exclusively shared between
the Timer0 module and the Watchdog Timer. Thus, a
prescaler assignment for the Timer0 module means
that there is no prescaler for the Watchdog Timer, and
vice-versa.
BSF
1,x....etc.) will clear the prescaler. When
assigned to WDT, a CLRWDT instruction will clear the
prescaler along with the Watchdog Timer. The pres-
caler is not readable or writable.
Note: Writing to TMR0 when the prescaler is
assigned to Timer0 will clear the prescaler
count, but will not change the prescaler
assignment.
FIGURE 7-6: BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER
Data Bus
8
CLKOUT (=Fosc/4)
M
U
X
1
0
0
1
M
U
X
RA4/T0CKI
pin
SYNC
2
Cycles
TMR0 reg
T0SE
T0CS
Set flag bit T0IF
on Overflow
PSA
0
1
8-bit Prescaler
M
U
X
Watchdog
Timer
8
8 - to - 1MUX
PS2:PS0
PSA
1
0
WDT Enable bit
M U X
PSA
WDT
Time-out
Note: T0CS, T0SE, PSA, PS2:PS0 are (OPTION<5:0>).
DS30390E-page 62
1997 Microchip Technology Inc.
PIC16C7X
7.3.1
SWITCHING PRESCALER ASSIGNMENT
The prescaler assignment is fully under software con-
trol, i.e., it can be changed “on the fly” during program
execution.
Note: To avoid an unintended device RESET, the
following instruction sequence (shown in
Example 7-1) must be executed when
changing the prescaler assignment from
Timer0 to the WDT. This sequence must
be followed even if the WDT is disabled.
EXAMPLE 7-1: CHANGING PRESCALER (TIMER0→WDT)
1) BSF
STATUS, RP0
;Bank 1
2) MOVLW b'xx0x0xxx'
3) MOVWF OPTION_REG
;Select clock source and prescale value of
Lines 2 and 3 do NOT have to
be included if the final desired
prescale value is other than 1:1.
If 1:1 is final desired value, then
a temporary prescale value is
set in lines 2 and 3 and the final
prescale value will be set in lines
10 and 11.
;other than 1:1
4) BCF
5) CLRF
6) BSF
STATUS, RP0
TMR0
;Bank 0
;Clear TMR0 and prescaler
STATUS, RP1
;Bank 1
7) MOVLW b'xxxx1xxx'
8) MOVWF OPTION_REG
9) CLRWDT
;Select WDT, do not change prescale value
;
;Clears WDT and prescaler
10) MOVLW b'xxxx1xxx'
11) MOVWF OPTION_REG
;Select new prescale value and WDT
;
12) BCF
STATUS, RP0
;Bank 0
To change prescaler from the WDT to the Timer0 mod-
ule use the sequence shown in Example 7-2.
EXAMPLE 7-2: CHANGING PRESCALER (WDT→TIMER0)
CLRWDT
BSF
;Clear WDT and prescaler
STATUS, RP0 ;Bank 1
MOVLW
MOVWF
BCF
b'xxxx0xxx' ;Select TMR0, new prescale value and
OPTION_REG ;clock source
STATUS, RP0 ;Bank 0
TABLE 7-1:
REGISTERS ASSOCIATED WITH TIMER0
Value on:
POR,
BOR
Value on all
other resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
01h,101h
TMR0
Timer0 module’s register
xxxx xxxx uuuu uuuu
RBIF 0000 000x 0000 000u
0Bh,8Bh,
10Bh,18Bh
INTCON
GIE
PEIE
T0IE
INTE
T0SE
RBIE
PSA
T0IF
PS2
INTF
PS1
81h,181h
85h
OPTION RBPU INTEDG
TRISA
T0CS
PS0
1111 1111 1111 1111
--11 1111 --11 1111
—
—
PORTA Data Direction Register
Legend: x= unknown, u= unchanged, -= unimplemented locations read as '0'. Shaded cells are not used by Timer0.
1997 Microchip Technology Inc.
DS30390E-page 63
PIC16C7X
NOTES:
DS30390E-page 64
1997 Microchip Technology Inc.
PIC16C7X
In timer mode, Timer1 increments every instruction
cycle. In counter mode, it increments on every rising
edge of the external clock input.
8.0
TIMER1 MODULE
Applicable Devices
72 73 73A 74 74A 76 77
Timer1 can be enabled/disabled by setting/clearing
control bit TMR1ON (T1CON<0>).
The Timer1 module is a 16-bit timer/counter consisting
of two 8-bit registers (TMR1H and TMR1L) which are
readable and writable. The TMR1 Register pair
(TMR1H:TMR1L) increments from 0000h to FFFFh
and rolls over to 0000h.The TMR1 Interrupt, if enabled,
is generated on overflow which is latched in interrupt
flag bit TMR1IF (PIR1<0>). This interrupt can be
enabled/disabled by setting/clearing TMR1 interrupt
enable bit TMR1IE (PIE1<0>).
Timer1 also has an internal “reset input”.This reset can
be generated by either of the two CCP modules
(Section 10.0). Figure 8-1 shows the Timer1 control
register.
For the PIC16C72/73A/74A/76/77, when the Timer1
oscillator is enabled (T1OSCEN is set), the RC1/
T1OSI/CCP2 and RC0/T1OSO/T1CKI pins become
inputs. That is, the TRISC<1:0> value is ignored.
Timer1 can operate in one of two modes:
For the PIC16C73/74, when the Timer1 oscillator is
enabled (T1OSCEN is set), RC1/T1OSI/CCP2 pin
becomes an input, however the RC0/T1OSO/T1CKI
pin will have to be configured as an input by setting the
TRISC<0> bit.
• As a timer
• As a counter
The operating mode is determined by the clock select
bit, TMR1CS (T1CON<1>).
FIGURE 8-1: T1CON:TIMER1 CONTROL REGISTER (ADDRESS 10h)
U-0
—
U-0
—
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R
= Readable bit
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
bit0
W = Writable bit
U
bit7
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-6: Unimplemented: Read as '0'
bit 5-4: T1CKPS1:T1CKPS0: Timer1 Input Clock Prescale Select bits
11= 1:8 Prescale value
10= 1:4 Prescale value
01= 1:2 Prescale value
00= 1:1 Prescale value
bit 3:
bit 2:
T1OSCEN: Timer1 Oscillator Enable Control bit
1 = Oscillator is enabled
0 = Oscillator is shut off
Note: The oscillator inverter and feedback resistor are turned off to eliminate power drain
T1SYNC: Timer1 External Clock Input Synchronization Control bit
TMR1CS = 1
1 = Do not synchronize external clock input
0 = Synchronize external clock input
TMR1CS = 0
This bit is ignored. Timer1 uses the internal clock when TMR1CS = 0.
bit 1:
bit 0:
TMR1CS: Timer1 Clock Source Select bit
1 = External clock from pin RC0/T1OSO/T1CKI (on the rising edge)
0 = Internal clock (FOSC/4)
TMR1ON: Timer1 On bit
1 = Enables Timer1
0 = Stops Timer1
1997 Microchip Technology Inc.
DS30390E-page 65
PIC16C7X
8.2.1
EXTERNAL CLOCK INPUT TIMING FOR
SYNCHRONIZED COUNTER MODE
8.1
Timer1 Operation in Timer Mode
Applicable Devices
72 73 73A 74 74A 76 77
When an external clock input is used for Timer1 in syn-
chronized counter mode, it must meet certain require-
ments. The external clock requirement is due to
internal phase clock (Tosc) synchronization. Also, there
is a delay in the actual incrementing of TMR1 after syn-
chronization.
Timer mode is selected by clearing the TMR1CS
(T1CON<1>) bit. In this mode, the input clock to the
timer is FOSC/4. The synchronize control bit T1SYNC
(T1CON<2>) has no effect since the internal clock is
always in sync.
When the prescaler is 1:1, the external clock input is
the same as the prescaler output. The synchronization
of T1CKI with the internal phase clocks is accom-
plished by sampling the prescaler output on the Q2 and
Q4 cycles of the internal phase clocks. Therefore, it is
necessary for T1CKI to be high for at least 2Tosc (and
a small RC delay of 20 ns) and low for at least 2Tosc
(and a small RC delay of 20 ns). Refer to the appropri-
ate electrical specifications, parameters 45, 46, and 47.
8.2
Timer1 Operation in Synchronized
Counter Mode
Applicable Devices
72 73 73A 74 74A 76 77
Counter mode is selected by setting bit TMR1CS. In
this mode the timer increments on every rising edge of
clock input on pin RC1/T1OSI/CCP2 when bit
T1OSCEN is set or pin RC0/T1OSO/T1CKI when bit
T1OSCEN is cleared.
When a prescaler other than 1:1 is used, the external
clock input is divided by the asynchronous ripple-
counter type prescaler so that the prescaler output is
symmetrical. In order for the external clock to meet the
sampling requirement, the ripple-counter must be
taken into account.Therefore, it is necessary for T1CKI
to have a period of at least 4Tosc (and a small RC delay
of 40 ns) divided by the prescaler value. The only
requirement on T1CKI high and low time is that they do
not violate the minimum pulse width requirements of
10 ns). Refer to the appropriate electrical specifica-
tions, parameters 40, 42, 45, 46, and 47.
If T1SYNC is cleared, then the external clock input is
synchronized with internal phase clocks. The synchro-
nization is done after the prescaler stage. The pres-
caler stage is an asynchronous ripple-counter.
In this configuration, during SLEEP mode, Timer1 will
not increment even if the external clock is present,
since the synchronization circuit is shut off. The pres-
caler however will continue to increment.
FIGURE 8-2: TIMER1 BLOCK DIAGRAM
Set flag bit
TMR1IF on
Overflow
Synchronized
0
TMR1
clock input
TMR1L
TMR1H
T1OSC
1
TMR1ON
on/off
T1SYNC
(3)
RC0/T1OSO/T1CKI
1
Synchronize
det
Prescaler
1, 2, 4, 8
T1OSCEN
Enable
Oscillator
FOSC/4
Internal
Clock
0
(1)
(2)
RC1/T1OSI/CCP2
2
SLEEP input
T1CKPS1:T1CKPS0
TMR1CS
Note 1: When the T1OSCEN bit is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
2: The CCP2 module is not implemented in the PIC16C72.
3: For the PIC16C73 and PIC16C74, the Schmitt Trigger is not implemented in external clock mode.
DS30390E-page 66
1997 Microchip Technology Inc.
PIC16C7X
8.3
Timer1 Operation in Asynchronous
Counter Mode
EXAMPLE 8-1: READING A 16-BIT FREE-
RUNNING TIMER
Applicable Devices
; All interrupts are disabled
72 73 73A 74 74A 76 77
MOVF
MOVWF TMPH
MOVF TMR1L, W ;Read low byte
MOVWF TMPL
MOVF TMR1H, W ;Read high byte
SUBWF TMPH,
TMR1H, W ;Read high byte
;
If control bit T1SYNC (T1CON<2>) is set, the external
clock input is not synchronized. The timer continues to
increment asynchronous to the internal phase clocks.
The timer will continue to run during SLEEP and can
generate an interrupt on overflow which will wake-up
the processor. However, special precautions in soft-
ware are needed to read/write the timer (Section 8.3.2).
;
W
;Sub 1st read
; with 2nd read
BTFSC STATUS,Z ;Is result = 0
GOTO CONTINUE ;Good 16-bit read
;
In asynchronous counter mode, Timer1 can not be
used as a time-base for capture or compare operations.
; TMR1L may have rolled over between the read
; of the high and low bytes. Reading the high
; and low bytes now will read a good value.
;
8.3.1
EXTERNAL CLOCK INPUT TIMING WITH
UNSYNCHRONIZED CLOCK
MOVF
MOVWF TMPH
MOVF TMR1L, W ;Read low byte
MOVWF TMPL
; Re-enable the Interrupt (if required)
CONTINUE ;Continue with your code
TMR1H, W ;Read high byte
;
If control bit T1SYNC is set, the timer will increment
completely asynchronously. The input clock must meet
certain minimum high time and low time requirements.
Refer to the appropriate Electrical Specifications Sec-
tion, timing parameters 45, 46, and 47.
;
8.4
Timer1 Oscillator
Applicable Devices
72 73 73A 74 74A 76 77
8.3.2
READING AND WRITING TIMER1 IN
ASYNCHRONOUS COUNTER MODE
Reading TMR1H or TMR1L while the timer is running,
from an external asynchronous clock, will guarantee a
valid read (taken care of in hardware). However, the
user should keep in mind that reading the 16-bit timer
in two 8-bit values itself poses certain problems since
the timer may overflow between the reads.
A crystal oscillator circuit is built in between pins T1OSI
(input) and T1OSO (amplifier output). It is enabled by
setting control bit T1OSCEN (T1CON<3>). The oscilla-
tor is a low power oscillator rated up to 200 kHz. It will
continue to run during SLEEP. It is primarily intended
for a 32 kHz crystal. Table 8-1 shows the capacitor
selection for the Timer1 oscillator.
For writes, it is recommended that the user simply stop
the timer and write the desired values. A write conten-
tion may occur by writing to the timer registers while the
register is incrementing. This may produce an unpre-
dictable value in the timer register.
The Timer1 oscillator is identical to the LP oscillator.
The user must provide a software time delay to ensure
proper oscillator start-up.
Reading the 16-bit value requires some care.
Example 8-1 is an example routine to read the 16-bit
timer value. This is useful if the timer cannot be
stopped.
TABLE 8-1:
CAPACITOR SELECTION
FOR THE TIMER1
OSCILLATOR
Osc Type
Freq
C1
C2
LP
32 kHz
100 kHz
200 kHz
33 pF
15 pF
15 pF
33 pF
15 pF
15 pF
These values are for design guidance only.
Crystals Tested:
32.768 kHz Epson C-001R32.768K-A ± 20 PPM
100 kHz
200 kHz
Epson C-2 100.00 KC-P
STD XTL 200.000 kHz
± 20 PPM
± 20 PPM
Note 1: Higher capacitance increases the stability
of oscillator but also increases the start-up
time.
2: Since each resonator/crystal has its own
characteristics, the user should consult the
resonator/crystal manufacturer for appropri-
ate values of external components.
1997 Microchip Technology Inc.
DS30390E-page 67
PIC16C7X
8.5
Resetting Timer1 using a CCP Trigger
Output
8.6
Resetting of Timer1 Register Pair
(TMR1H,TMR1L)
Applicable Devices
72 73 73A 74 74A 76 77
Applicable Devices
72 73 73A 74 74A 76 77
The CCP2 module is not implemented on the
PIC16C72 device.
TMR1H and TMR1L registers are not reset to 00h on a
POR or any other reset except by the CCP1 and CCP2
special event triggers.
If the CCP1 or CCP2 module is configured in compare
mode to generate
(CCP1M3:CCP1M0 = 1011), this signal will reset
Timer1.
a
“special event trigger"
T1CON register is reset to 00h on a Power-on Reset or
a Brown-out Reset, which shuts off the timer and
leaves a 1:1 prescale. In all other resets, the register is
unaffected.
Note: The special event triggers from the CCP1
and CCP2 modules will not set interrupt
flag bit TMR1IF (PIR1<0>).
8.7
Timer1 Prescaler
Applicable Devices
72 73 73A 74 74A 76 77
Timer1 must be configured for either timer or synchro-
nized counter mode to take advantage of this feature.
If Timer1 is running in asynchronous counter mode, this
reset operation may not work.
The prescaler counter is cleared on writes to the
TMR1H or TMR1L registers.
In the event that a write to Timer1 coincides with a spe-
cial event trigger from CCP1 or CCP2, the write will
take precedence.
In this mode of operation, the CCPRxH:CCPRxL regis-
ters pair effectively becomes the period register for
Timer1.
TABLE 8-2:
REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Value on:
POR,
BOR
Value on
all other
resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0000 000x 0000 000u
0Bh,8Bh,
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
10Bh,18Bh
(1,2)
(2)
(2)
(2)
0000 0000 0000 0000
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
--00 0000 --uu uuuu
0Ch
8Ch
0Eh
0Fh
10h
PIR1
PIE1
PSPIF
PSPIE
ADIF RCIF
ADIE RCIE
TXIF
TXIE
SSPIF
SSPIE
CCP1IF TMR2IF TMR1IF
CCP1IE TMR2IE TMR1IE
(1,2)
(2)
TMR1L Holding register for the Least Significant Byte of the 16-bit TMR1 register
TMR1H Holding register for the Most Significant Byte of the 16-bit TMR1 register
T1CON
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by the Timer1 module.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
2: The PIC16C72 does not have a Parallel Slave Port or a USART, these bits are unimplemented, read as '0'.
DS30390E-page 68
1997 Microchip Technology Inc.
PIC16C7X
9.1
Timer2 Prescaler and Postscaler
Applicable Devices
9.0
TIMER2 MODULE
Applicable Devices
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
The prescaler and postscaler counters are cleared
when any of the following occurs:
Timer2 is an 8-bit timer with a prescaler and a
postscaler. It can be used as the PWM time-base for
PWM mode of the CCP module(s). The TMR2 register
is readable and writable, and is cleared on any device
reset.
• a write to the TMR2 register
• a write to the T2CON register
• any device reset (Power-on Reset, MCLR reset,
Watchdog Timer reset, or Brown-out Reset)
The input clock (FOSC/4) has a prescale option of 1:1,
1:4
or
1:16,
selected
by
control
bits
TMR2 is not cleared when T2CON is written.
T2CKPS1:T2CKPS0 (T2CON<1:0>).
9.2
Output of TMR2
Applicable Devices
72 73 73A 74 74A 76 77
The Timer2 module has an 8-bit period register PR2.
Timer2 increments from 00h until it matches PR2 and
then resets to 00h on the next increment cycle. PR2 is
a readable and writable register.The PR2 register is ini-
tialized to FFh upon reset.
The output of TMR2 (before the postscaler) is fed to the
Synchronous Serial Port module which optionally uses
it to generate shift clock.
The match output of TMR2 goes through a 4-bit
postscaler (which gives a 1:1 to 1:16 scaling inclusive)
to generate a TMR2 interrupt (latched in flag bit
TMR2IF, (PIR1<1>)).
FIGURE 9-1: TIMER2 BLOCK DIAGRAM
Sets flag
TMR2
output (1)
bit TMR2IF
Timer2 can be shut off by clearing control bit TMR2ON
(T2CON<2>) to minimize power consumption.
Reset
Prescaler
1:1, 1:4, 1:16
Figure 9-2 shows the Timer2 control register.
TMR2 reg
FOSC/4
Postscaler
1:1 to 1:16
2
Comparator
EQ
4
PR2 reg
Note 1: TMR2 register output can be software selected
by the SSP Module as a baud clock.
1997 Microchip Technology Inc.
DS30390E-page 69
PIC16C7X
FIGURE 9-2: T2CON:TIMER2 CONTROL REGISTER (ADDRESS 12h)
U-0
—
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0
bit0
R
= Readable bit
W = Writable bit
U
bit7
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
Unimplemented: Read as '0'
bit 6-3: TOUTPS3:TOUTPS0: Timer2 Output Postscale Select bits
0000= 1:1 Postscale
0001= 1:2 Postscale
•
•
•
1111= 1:16 Postscale
bit 2:
TMR2ON: Timer2 On bit
1 = Timer2 is on
0 = Timer2 is off
bit 1-0: T2CKPS1:T2CKPS0: Timer2 Clock Prescale Select bits
00= Prescaler is 1
01= Prescaler is 4
1x= Prescaler is 16
TABLE 9-1:
REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER
Value on:
POR,
BOR
Value on
all other
resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0000 000x 0000 000u
0Bh,8Bh,
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
10Bh,18Bh
PSPIF(1,2)
PSPIE(1,2)
ADIF
ADIE
RCIF(2)
RCIE(2)
TXIF(2)
TXIE(2)
SSPIF
SSPIE
CCP1IF
CCP1IE
TMR2IF
TMR2IE
TMR1IF
TMR1IE
0000 0000 0000 0000
0000 0000 0000 0000
0000 0000 0000 0000
-000 0000 -000 0000
1111 1111 1111 1111
0Ch
PIR1
8Ch
PIE1
11h
TMR2
T2CON
PR2
Timer2 module’s register
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0
Timer2 Period Register
12h
—
92h
Legend:
x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by the Timer2 module.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
2: The PIC16C72 does not have a Parallel Slave Port or a USART, these bits are unimplemented, read as '0'.
DS30390E-page 70
1997 Microchip Technology Inc.
PIC16C7X
CCP1 module:
10.0 CAPTURE/COMPARE/PWM
MODULE(s)
Capture/Compare/PWM Register1 (CCPR1) is com-
prised of two 8-bit registers: CCPR1L (low byte) and
CCPR1H (high byte). The CCP1CON register controls
the operation of CCP1. All are readable and writable.
Applicable Devices
72 73 73A 74 74A 76 77 CCP1
72 73 73A 74 74A 76 77 CCP2
CCP2 module:
Each CCP (Capture/Compare/PWM) module contains
a 16-bit register which can operate as a 16-bit capture
register, as a 16-bit compare register or as a PWM
master/slave Duty Cycle register. Both the CCP1 and
CCP2 modules are identical in operation, with the
exception of the operation of the special event trigger.
Table 10-1 and Table 10-2 show the resources and
interactions of the CCP module(s). In the following sec-
tions, the operation of a CCP module is described with
respect to CCP1. CCP2 operates the same as CCP1,
except where noted.
Capture/Compare/PWM Register2 (CCPR2) is com-
prised of two 8-bit registers: CCPR2L (low byte) and
CCPR2H (high byte). The CCP2CON register controls
the operation of CCP2. All are readable and writable.
For use of the CCP modules, refer to the Embedded
Control Handbook, "Using the CCP Modules" (AN594).
TABLE 10-1: CCP MODE - TIMER
RESOURCE
CCP Mode
Timer Resource
Capture
Compare
PWM
Timer1
Timer1
Timer2
TABLE 10-2: INTERACTION OF TWO CCP MODULES
CCPx Mode CCPy Mode
Interaction
Capture
Capture
Compare
PWM
Capture
Compare
Compare
PWM
Same TMR1 time-base.
The compare should be configured for the special event trigger, which clears TMR1.
The compare(s) should be configured for the special event trigger, which clears TMR1.
The PWMs will have the same frequency, and update rate (TMR2 interrupt).
PWM
Capture
Compare
None
None
PWM
1997 Microchip Technology Inc.
DS30390E-page 71
PIC16C7X
FIGURE 10-1: CCP1CON REGISTER (ADDRESS 17h)/CCP2CON REGISTER (ADDRESS 1Dh)
U-0
—
U-0
—
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
CCPxX CCPxY CCPxM3 CCPxM2 CCPxM1 CCPxM0
bit0
R = Readable bit
W = Writable bit
bit7
U = Unimplemented bit,
read as ‘0’
- n =Value at POR reset
bit 7-6: Unimplemented: Read as '0'
bit 5-4: CCPxX:CCPxY: PWM Least Significant bits
Capture Mode: Unused
Compare Mode: Unused
PWM Mode: These bits are the two LSbs of the PWM duty cycle. The eight MSbs are found in CCPRxL.
bit 3-0: CCPxM3:CCPxM0: CCPx Mode Select bits
0000= Capture/Compare/PWM off (resets CCPx module)
0100= Capture mode, every falling edge
0101= Capture mode, every rising edge
0110= Capture mode, every 4th rising edge
0111= Capture mode, every 16th rising edge
1000= Compare mode, set output on match (CCPxIF bit is set)
1001= Compare mode, clear output on match (CCPxIF bit is set)
1010= Compare mode, generate software interrupt on match (CCPxIF bit is set, CCPx pin is unaffected)
1011= Compare mode, trigger special event (CCPxIF bit is set; CCP1 resets TMR1; CCP2 resets TMR1
and starts an A/D conversion (if A/D module is enabled))
11xx= PWM mode
10.1
Capture Mode
Applicable Devices
72 73 73A 74 74A 76 77
FIGURE 10-2: CAPTURE MODE
OPERATION BLOCK
DIAGRAM
In Capture mode, CCPR1H:CCPR1L captures the
16-bit value of the TMR1 register when an event occurs
on pin RC2/CCP1. An event is defined as:
Set flag bit CCP1IF
(PIR1<2>)
Prescaler
÷ 1, 4, 16
RC2/CCP1
Pin
CCPR1H
CCPR1L
TMR1L
• Every falling edge
• Every rising edge
Capture
Enable
and
edge detect
• Every 4th rising edge
• Every 16th rising edge
TMR1H
CCP1CON<3:0>
An event is selected by control bits CCP1M3:CCP1M0
(CCP1CON<3:0>). When a capture is made, the inter-
rupt request flag bit CCP1IF (PIR1<2>) is set. It must
be cleared in software. If another capture occurs before
the value in register CCPR1 is read, the old captured
value will be lost.
Q’s
10.1.2 TIMER1 MODE SELECTION
Timer1 must be running in timer mode or synchronized
counter mode for the CCP module to use the capture
feature. In asynchronous counter mode, the capture
operation may not work.
10.1.1 CCP PIN CONFIGURATION
In Capture mode, the RC2/CCP1 pin should be config-
ured as an input by setting the TRISC<2> bit.
10.1.3 SOFTWARE INTERRUPT
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep bit
CCP1IE (PIE1<2>) clear to avoid false interrupts and
should clear the flag bit CCP1IF following any such
change in operating mode.
Note: If the RC2/CCP1 is configured as an out-
put, a write to the port can cause a capture
condition.
DS30390E-page 72
1997 Microchip Technology Inc.
PIC16C7X
10.1.4 CCP PRESCALER
10.2.1 CCP PIN CONFIGURATION
There are four prescaler settings, specified by bits
CCP1M3:CCP1M0. Whenever the CCP module is
turned off, or the CCP module is not in capture mode,
the prescaler counter is cleared. This means that any
reset will clear the prescaler counter.
The user must configure the RC2/CCP1 pin as an out-
put by clearing the TRISC<2> bit.
Note: Clearing the CCP1CON register will force
the RC2/CCP1 compare output latch to the
default low level. This is not the data latch.
Switching from one capture prescaler to another may
generate an interrupt. Also, the prescaler counter will
not be cleared, therefore the first capture may be from
a non-zero prescaler. Example 10-1 shows the recom-
mended method for switching between capture pres-
calers. This example also clears the prescaler counter
and will not generate the “false” interrupt.
10.2.2 TIMER1 MODE SELECTION
Timer1 must be running in Timer mode or Synchro-
nized Counter mode if the CCP module is using the
compare feature. In Asynchronous Counter mode, the
compare operation may not work.
10.2.3 SOFTWARE INTERRUPT MODE
EXAMPLE 10-1: CHANGING BETWEEN
CAPTURE PRESCALERS
When generate software interrupt is chosen the CCP1
pin is not affected. Only a CCP interrupt is generated (if
enabled).
CLRF
CCP1CON
;Turn CCP module off
MOVLW NEW_CAPT_PS ;Load the W reg with
; the new prescaler
10.2.4 SPECIAL EVENT TRIGGER
; mode value and CCP ON
MOVWF CCP1CON
;Load CCP1CON with this
; value
In this mode, an internal hardware trigger is generated
which may be used to initiate an action.
The special event trigger output of CCP1 resets the
TMR1 register pair. This allows the CCPR1 register to
effectively be a 16-bit programmable period register for
Timer1.
10.2
Compare Mode
Applicable Devices
72 73 73A 74 74A 76 77
In Compare mode, the 16-bit CCPR1 register value is
constantly compared against the TMR1 register pair
value. When a match occurs, the RC2/CCP1 pin is:
The special trigger output of CCP2 resets the TMR1
register pair, and starts an A/D conversion (if the A/D
module is enabled).
• Driven High
For the PIC16C72 only, the special event trigger output
of CCP1 resets the TMR1 register pair, and starts an
A/D conversion (if the A/D module is enabled).
• Driven Low
• Remains Unchanged
The action on the pin is based on the value of control
bits CCP1M3:CCP1M0 (CCP1CON<3:0>). At the
same time, interrupt flag bit CCP1IF is set.
Note: The special event trigger from the
CCP1and CCP2 modules will not set inter-
rupt flag bit TMR1IF (PIR1<0>).
FIGURE 10-3: COMPARE MODE
OPERATION BLOCK
DIAGRAM
Special event trigger will:
reset Timer1, but not set interrupt flag bit TMR1IF (PIR1<0>),
and set bit GO/DONE (ADCON0<2>)
which starts an A/D conversion (CCP1 only for PIC16C72,
CCP2 only for PIC16C73/73A/74/74A/76/77).
Special Event Trigger
Set flag bit CCP1IF
(PIR1<2>)
CCPR1H CCPR1L
Q
S
R
Output
Logic
Comparator
match
RC2/CCP1
Pin
TRISC<2>
Output Enable
TMR1H TMR1L
CCP1CON<3:0>
Mode Select
1997 Microchip Technology Inc.
DS30390E-page 73
PIC16C7X
10.3.1 PWM PERIOD
10.3
PWM Mode
Applicable Devices
72 73 73A 74 74A 76 77
The PWM period is specified by writing to the PR2 reg-
ister. The PWM period can be calculated using the fol-
lowing formula:
In Pulse Width Modulation (PWM) mode, the CCPx pin
produces up to a 10-bit resolution PWM output. Since
the CCP1 pin is multiplexed with the PORTC data latch,
the TRISC<2> bit must be cleared to make the CCP1
pin an output.
PWM period = [(PR2) + 1] • 4 • TOSC •
(TMR2 prescale value)
PWM frequency is defined as 1 / [PWM period].
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
Note: Clearing the CCP1CON register will force
the CCP1 PWM output latch to the default
low level. This is not the PORTC I/O data
latch.
• TMR2 is cleared
• The CCP1 pin is set (exception: if PWM duty
cycle = 0%, the CCP1 pin will not be set)
Figure 10-4 shows a simplified block diagram of the
CCP module in PWM mode.
• The PWM duty cycle is latched from CCPR1L into
CCPR1H
For a step by step procedure on how to set up the CCP
module for PWM operation, see Section 10.3.3.
Note: The Timer2 postscaler (see Section 9.1) is
not used in the determination of the PWM
frequency.The postscaler could be used to
have a servo update rate at a different fre-
quency than the PWM output.
FIGURE 10-4: SIMPLIFIED PWM BLOCK
DIAGRAM
CCP1CON<5:4>
Duty cycle registers
CCPR1L
10.3.2 PWM DUTY CYCLE
The PWM duty cycle is specified by writing to the
CCPR1L register and to the CCP1CON<5:4> bits. Up
to 10-bit resolution is available: the CCPR1L contains
the eight MSbs and the CCP1CON<5:4> contains the
two LSbs. This 10-bit value is represented by
CCPR1L:CCP1CON<5:4>. The following equation is
used to calculate the PWM duty cycle in time:
CCPR1H (Slave)
Q
R
S
Comparator
TMR2
RC2/CCP1
(Note 1)
PWM duty cycle = (CCPR1L:CCP1CON<5:4>) •
Tosc • (TMR2 prescale value)
TRISC<2>
Comparator
CCPR1L and CCP1CON<5:4> can be written to at any
time, but the duty cycle value is not latched into
CCPR1H until after a match between PR2 and TMR2
occurs (i.e., the period is complete). In PWM mode,
CCPR1H is a read-only register.
Clear Timer,
CCP1 pin and
latch D.C.
PR2
Note 1: 8-bit timer is concatenated with 2-bit internal Q clock
or 2 bits of the prescaler to create 10-bit time-base.
The CCPR1H register and a 2-bit internal latch are
used to double buffer the PWM duty cycle. This double
buffering is essential for glitchless PWM operation.
A PWM output (Figure 10-5) has a time base (period)
and a time that the output stays high (duty cycle). The
frequency of the PWM is the inverse of the period
(1/period).
When the CCPR1H and 2-bit latch match TMR2 con-
catenated with an internal 2-bit Q clock or 2 bits of the
TMR2 prescaler, the CCP1 pin is cleared.
FIGURE 10-5: PWM OUTPUT
Maximum PWM resolution (bits) for a given PWM
frequency:
Period
FOSC
log(
)
FPWM
=
bits
log(2)
Duty Cycle
TMR2 = PR2
Note: If the PWM duty cycle value is longer than
the PWM period the CCP1 pin will not be
cleared.
TMR2 = Duty Cycle
TMR2 = PR2
DS30390E-page 74
1997 Microchip Technology Inc.
PIC16C7X
In order to achieve higher resolution, the PWM fre-
quency must be decreased. In order to achieve higher
PWM frequency, the resolution must be decreased.
EXAMPLE 10-2: PWM PERIOD AND DUTY
CYCLE CALCULATION
Desired PWM frequency is 78.125 kHz,
Fosc = 20 MHz
TMR2 prescale = 1
Table 10-3 lists example PWM frequencies and resolu-
tions for Fosc = 20 MHz. The TMR2 prescaler and PR2
values are also shown.
1/78.125 kHz= [(PR2) + 1] • 4 • 1/20 MHz • 1
10.3.3 SET-UP FOR PWM OPERATION
12.8 µs = [(PR2) + 1] • 4 • 50 ns • 1
PR2
= 63
The following steps should be taken when configuring
the CCP module for PWM operation:
Find the maximum resolution of the duty cycle that can
be used with a 78.125 kHz frequency and 20 MHz
oscillator:
1. Set the PWM period by writing to the PR2 regis-
ter.
1/78.125 kHz= 2PWM RESOLUTION • 1/20 MHz • 1
12.8 µs = 2PWM RESOLUTION • 50 ns • 1
2. Set the PWM duty cycle by writing to the
CCPR1L register and CCP1CON<5:4> bits.
3. Make the CCP1 pin an output by clearing the
TRISC<2> bit.
256
log(256) = (PWM Resolution) • log(2)
8.0 = PWM Resolution
= 2PWM RESOLUTION
4. Set the TMR2 prescale value and enable Timer2
by writing to T2CON.
5. Configure the CCP1 module for PWM operation.
At most, an 8-bit resolution duty cycle can be obtained
from a 78.125 kHz frequency and a 20 MHz oscillator,
i.e., 0 ≤ CCPR1L:CCP1CON<5:4> ≤ 255. Any value
greater than 255 will result in a 100% duty cycle.
TABLE 10-3: EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 20 MHz
PWM Frequency
Timer Prescaler (1, 4, 16)
1.22 kHz 4.88 kHz 19.53 kHz 78.12 kHz 156.3 kHz 208.3 kHz
16
0xFF
10
4
1
1
0x3F
8
1
0x1F
7
1
PR2 Value
0xFF
10
0xFF
10
0x17
5.5
Maximum Resolution (bits)
TABLE 10-4: REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, AND TIMER1
Value on:
POR,
BOR
Value on
all other
resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0Bh,8Bh, INTCON
10Bh,18Bh
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
0Ch
PIR1
PSPIF(1,2) ADIF RCIF(2)
TXIF(2)
—
SSPIF
—
CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
CCP2IF ---- ---0 ---- ---0
CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
0Dh(2)
PIR2
—
—
—
—
—
8Ch
PIE1
PSPIE(1,2) ADIE RCIE(2)
TXIE(2)
SSPIE
—
8Dh(2)
87h
PIE2
—
—
—
—
—
—
CCP2IE ---- ---0 ---- ---0
1111 1111 1111 1111
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
TRISC
TMR1L
TMR1H
T1CON
CCPR1L
PORTC Data Direction Register
0Eh
Holding register for the Least Significant Byte of the 16-bit TMR1 register
Holding register for the Most Significant Byte of the 16-bit TMR1register
0Fh
10h
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
15h
Capture/Compare/PWM register1 (LSB)
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
16h
CCPR1H Capture/Compare/PWM register1 (MSB)
17h
CCP1CON
CCPR2L
—
—
CCP1X
CCP1Y
CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
xxxx xxxx uuuu uuuu
1Bh(2)
1Ch(2)
1Dh(2)
Capture/Compare/PWM register2 (LSB)
CCPR2H Capture/Compare/PWM register2 (MSB)
CCP2CON CCP2X CCP2Y
xxxx xxxx uuuu uuuu
—
—
CCP2M3 CCP2M2 CCP2M1 CCP2M0 --00 0000 --00 0000
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by Capture and Timer1.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
2: The PIC16C72 does not have a Parallel Slave Port, USART or CCP2 module, these bits are unimplemented, read as '0'.
1997 Microchip Technology Inc.
DS30390E-page 75
PIC16C7X
TABLE 10-5: REGISTERS ASSOCIATED WITH PWM AND TIMER2
Value on:
POR,
BOR
Value on
all other
resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0Bh,8Bh, INTCON
10Bh,18Bh
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
0Ch
PIR1
PSPIF(1,2)
—
ADIF
—
RCIF(2)
—
TXIF(2)
—
SSPIF
—
CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
CCP2IF ---- ---0 ---- ---0
CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
0Dh(2)
PIR2
—
—
8Ch
PIE1
PSPIE(1,2)
ADIE
—
RCIE(2)
TXIE(2)
SSPIE
—
8Dh(2)
87h
PIE2
—
—
—
—
—
CCP2IE ---- ---0 ---- ---0
1111 1111 1111 1111
0000 0000 0000 0000
TRISC
TMR2
PORTC Data Direction Register
Timer2 module’s register
11h
92h
PR2
Timer2 module’s period register
1111 1111 1111 1111
12h
T2CON
CCPR1L
CCPR1H
CCP1CON
CCPR2L
CCPR2H
CCP2CON
—
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
15h
Capture/Compare/PWM register1 (LSB)
Capture/Compare/PWM register1 (MSB)
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
16h
17h
—
—
CCP1X
CCP1Y CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
1Bh(2)
1Ch(2)
1Dh(2)
Capture/Compare/PWM register2 (LSB)
Capture/Compare/PWM register2 (MSB)
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
—
—
CCP2X
CCP2Y CCP2M3 CCP2M2 CCP2M1 CCP2M0 --00 0000 --00 0000
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by PWM and Timer2.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
2: The PIC16C72 does not have a Parallel Slave Port, USART or CCP2 module, these bits are unimplemented, read as '0'.
DS30390E-page 76
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.0 SYNCHRONOUS SERIAL
PORT (SSP) MODULE
11.1
SSP Module Overview
The Synchronous Serial Port (SSP) module is a serial
interface useful for communicating with other periph-
eral or microcontroller devices. These peripheral
devices may be Serial EEPROMs, shift registers, dis-
play drivers, A/D converters, etc. The SSP module can
operate in one of two modes:
• Serial Peripheral Interface (SPI)
• Inter-Integrated Circuit (I2C)
2
The SSP module in I C mode works the same in all
PIC16C7X devices that have an SSP module. However
the SSP Module in SPI mode has differences between
the PIC16C76/77 and the other PIC16C7X devices.
The register definitions and operational description of
SPI mode has been split into two sections because of
the differences between the PIC16C76/77 and the
other PIC16C7X devices. The default reset values of
both the SPI modules is the same regardless of the
device:
11.2 SPI Mode for PIC16C72/73/73A/74/74A..........78
11.3 SPI Mode for PIC16C76/77..............................83
11.4 I2C™ Overview ................................................89
11.5 SSP I2C Operation...........................................93
Refer to Application Note AN578, “Use of the SSP
2
Module in the I C Multi-Master Environment.”
1997 Microchip Technology Inc.
DS30390E-page 77
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.2
SPI Mode for PIC16C72/73/73A/74/74A
This section contains register definitions and opera-
tional characteristics of the SPI module for the
PIC16C72, PIC16C73, PIC16C73A, PIC16C74,
PIC16C74A.
FIGURE 11-1: SSPSTAT: SYNC SERIAL PORT STATUS REGISTER (ADDRESS 94h)
U-0
—
U-0
—
R-0
D/A
R-0
P
R-0
S
R-0
R-0
UA
R-0
BF
R/W
R = Readable bit
W = Writable bit
bit7
bit0
U = Unimplemented bit,
read as ‘0’
- n =Value at POR reset
bit 7-6: Unimplemented: Read as '0'
2
bit 5:
bit 4:
bit 3:
bit 2:
D/A: Data/Address bit (I C mode only)
1 = Indicates that the last byte received or transmitted was data
0 = Indicates that the last byte received or transmitted was address
2
P: Stop bit (I C mode only. This bit is cleared when the SSP module is disabled, SSPEN is cleared)
1 = Indicates that a stop bit has been detected last (this bit is '0' on RESET)
0 = Stop bit was not detected last
2
S: Start bit (I C mode only. This bit is cleared when the SSP module is disabled, SSPEN is cleared)
1 = Indicates that a start bit has been detected last (this bit is '0' on RESET)
0 = Start bit was not detected last
2
R/W: Read/Write bit information (I C mode only)
This bit holds the R/W bit information following the last address match. This bit is valid from the address
match to the next start bit, stop bit, or ACK bit.
1 = Read
0 = Write
2
bit 1:
bit 0:
UA: Update Address (10-bit I C mode only)
1 = Indicates that the user needs to update the address in the SSPADD register
0 = Address does not need to be updated
BF: Buffer Full Status bit
2
Receive (SPI and I C modes)
1 = Receive complete, SSPBUF is full
0 = Receive not complete, SSPBUF is empty
2
Transmit (I C mode only)
1 = Transmit in progress, SSPBUF is full
0 = Transmit complete, SSPBUF is empty
DS30390E-page 78
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
FIGURE 11-2: SSPCON: SYNC SERIAL PORT CONTROL REGISTER (ADDRESS 14h)
R/W-0
R/W-0
R/W-0
R/W-0
CKP
R/W-0
R/W-0
R/W-0
R/W-0
WCOL SSPOV SSPEN
bit7
SSPM3 SSPM2 SSPM1 SSPM0
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as ‘0’
- n =Value at POR reset
bit 7:
WCOL: Write Collision Detect bit
1 = The SSPBUF register is written while it is still transmitting the previous word
(must be cleared in software)
0 = No collision
bit 6:
SSPOV: Receive Overflow Detect bit
In SPI mode
1 = A new byte is received while the SSPBUF register is still holding the previous data. In case of overflow,
the data in SSPSR register is lost. Overflow can only occur in slave mode. The user must read the SSP-
BUF, even if only transmitting data, to avoid setting overflow. In master mode the overflow bit is not set
since each new reception (and transmission) is initiated by writing to the SSPBUF register.
0 = No overflow
2
In I C mode
1 = A byte is received while the SSPBUF register is still holding the previous byte. SSPOV is a "don’t care"
in transmit mode. SSPOV must be cleared in software in either mode.
0 = No overflow
bit 5:
SSPEN: Synchronous Serial Port Enable bit
In SPI mode
1 = Enables serial port and configures SCK, SDO, and SDI as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
2
In I C mode
1 = Enables the serial port and configures the SDA and SCL pins as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
In both modes, when enabled, these pins must be properly configured as input or output.
bit 4:
CKP: Clock Polarity Select bit
In SPI mode
1 = Idle state for clock is a high level. Transmit happens on falling edge, receive on rising edge.
0 = Idle state for clock is a low level. Transmit happens on rising edge, receive on falling edge.
2
In I C mode
SCK release control
1 = Enable clock
0 = Holds clock low (clock stretch) (Used to ensure data setup time)
bit 3-0: SSPM3:SSPM0: Synchronous Serial Port Mode Select bits
0000= SPI master mode, clock = Fosc/4
0001= SPI master mode, clock = Fosc/16
0010= SPI master mode, clock = Fosc/64
0011= SPI master mode, clock = TMR2 output/2
0100= SPI slave mode, clock = SCK pin. SS pin control enabled.
0101= SPI slave mode, clock = SCK pin. SS pin control disabled. SS can be used as I/O pin.
2
0110= I C slave mode, 7-bit address
2
0111= I C slave mode, 10-bit address
2
1011= I C firmware controlled Master Mode (slave idle)
2
1110= I C slave mode, 7-bit address with start and stop bit interrupts enabled
2
1111= I C slave mode, 10-bit address with start and stop bit interrupts enabled
1997 Microchip Technology Inc.
DS30390E-page 79
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.2.1 OPERATION OF SSP MODULE IN SPI
MODE
EXAMPLE 11-1: LOADING THE SSPBUF
(SSPSR) REGISTER
Applicable Devices
BSF
STATUS, RP0
;Specify Bank 1
;Has data been
;received
;(transmit
;complete)?
LOOP BTFSS SSPSTAT, BF
72 73 73A 74 74A 76 77
The SPI mode allows 8-bits of data to be synchro-
nously transmitted and received simultaneously. To
accomplish communication, typically three pins are
used:
GOTO LOOP
BCF
MOVF SSPBUF, W
;No
STATUS, RP0
;Specify Bank 0
;W reg = contents
;of SSPBUF
;Save in user RAM
;W reg = contents
; of TXDATA
• Serial Data Out (SDO)
• Serial Data In (SDI)
• Serial Clock (SCK)
MOVWF RXDATA
MOVF TXDATA, W
Additionally a fourth pin may be used when in a slave
mode of operation:
MOVWF SSPBUF
;New data to xmit
• Slave Select (SS)
The block diagram of the SSP module, when in SPI
mode (Figure 11-3), shows that the SSPSR register is
not directly readable or writable, and can only be
accessed from addressing the SSPBUF register. Addi-
tionally, the SSP status register (SSPSTAT) indicates
the various status conditions.
When initializing the SPI, several options need to be
specified.This is done by programming the appropriate
control bits in the SSPCON register (SSPCON<5:0>).
These control bits allow the following to be specified:
• Master Mode (SCK is the clock output)
• Slave Mode (SCK is the clock input)
FIGURE 11-3: SSP BLOCK DIAGRAM
(SPI MODE)
• Clock Polarity (Output/Input data on the Rising/
Falling edge of SCK)
• Clock Rate (Master mode only)
• Slave Select Mode (Slave mode only)
Internal
data bus
The SSP consists of a transmit/receive Shift Register
(SSPSR) and a Buffer register (SSPBUF). The SSPSR
shifts the data in and out of the device, MSb first. The
SSPBUF holds the data that was written to the SSPSR,
until the received data is ready. Once the 8-bits of data
have been received, that byte is moved to the SSPBUF
register. Then the Buffer Full bit, BF (SSPSTAT<0>)
and flag bit SSPIF are set. This double buffering of the
received data (SSPBUF) allows the next byte to start
reception before reading the data that was just
received. Any write to the SSPBUF register during
transmission/reception of data will be ignored, and the
write collision detect bit, WCOL (SSPCON<7>) will be
set. User software must clear bit WCOL so that it can
be determined if the following write(s) to the SSPBUF
completed successfully. When the application software
is expecting to receive valid data, the SSPBUF register
should be read before the next byte of data to transfer
is written to the SSPBUF register.The Buffer Full bit BF
(SSPSTAT<0>) indicates when the SSPBUF register
has been loaded with the received data (transmission
is complete). When the SSPBUF is read, bit BF is
cleared. This data may be irrelevant if the SPI is only a
transmitter. Generally the SSP Interrupt is used to
determine when the transmission/reception has com-
pleted. The SSPBUF register must be read and/or writ-
ten. If the interrupt method is not going to be used, then
software polling can be done to ensure that a write col-
lision does not occur. Example 11-1 shows the loading
of the SSPBUF (SSPSR) register for data transmission.
The shaded instruction is only required if the received
data is meaningful.
Read
Write
SSPBUF reg
SSPSR reg
shift
clock
RC4/SDI/SDA
RC5/SDO
bit0
Control
Enable
SS
RA5/SS/AN4
Edge
Select
2
Clock Select
SSPM3:SSPM0
4
TMR2 output
2
Edge
Select
TCY
Prescaler
4, 16, 64
RC3/SCK/
SCL
TRISC<3>
DS30390E-page 80
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
To enable the serial port, SSP enable bit SSPEN
The master can initiate the data transfer at any time
because it controls the SCK. The master determines
when the slave (Processor 2) is to broadcast data by
the software protocol.
(SSPCON<5>) must be set.To reset or reconfigure SPI
mode, clear enable bit SSPEN, re-initialize SSPCON
register, and then set enable bit SSPEN. This config-
ures the SDI, SDO, SCK, and SS pins as serial port
pins. For the pins to behave as the serial port function,
they must have their data direction bits (in the TRIS reg-
ister) appropriately programmed. That is:
In master mode the data is transmitted/received as
soon as the SSPBUF register is written to. If the SPI is
only going to receive, the SCK output could be disabled
(programmed as an input). The SSPSR register will
continue to shift in the signal present on the SDI pin at
the programmed clock rate. As each byte is received, it
will be loaded into the SSPBUF register as if a normal
received byte (interrupts and status bits appropriately
set). This could be useful in receiver applications as a
“line activity monitor” mode.
• SDI must have TRISC<4> set
• SDO must have TRISC<5> cleared
• SCK (Master mode) must have TRISC<3>
cleared
• SCK (Slave mode) must have TRISC<3> set
• SS must have TRISA<5> set (if implemented)
In slave mode, the data is transmitted and received as
the external clock pulses appear on SCK. When the
last bit is latched interrupt flag bit SSPIF (PIR1<3>) is
set.
Any serial port function that is not desired may be over-
ridden by programming the corresponding data direc-
tion (TRIS) register to the opposite value. An example
would be in master mode where you are only sending
data (to a display driver), then both SDI and SS could
be used as general purpose outputs by clearing their
corresponding TRIS register bits.
The clock polarity is selected by appropriately program-
ming bit CKP (SSPCON<4>). This then would give
waveforms for SPI communication as shown in
Figure 11-5 and Figure 11-6 where the MSB is trans-
mitted first. In master mode, the SPI clock rate (bit rate)
is user programmable to be one of the following:
Figure 11-4 shows a typical connection between two
microcontrollers. The master controller (Processor 1)
initiates the data transfer by sending the SCK signal.
Data is shifted out of both shift registers on their pro-
grammed clock edge, and latched on the opposite edge
of the clock. Both processors should be programmed to
the same Clock Polarity (CKP), then both controllers
would send and receive data at the same time.
Whether the data is meaningful (or dummy data)
depends on the application software. This leads to
three scenarios for data transmission:
• Fosc/4 (or TCY)
• Fosc/16 (or 4 • TCY)
• Fosc/64 (or 16 • TCY)
• Timer2 output/2
This allows a maximum bit clock frequency (at 20 MHz)
of 5 MHz. When in slave mode the external clock must
meet the minimum high and low times.
In sleep mode, the slave can transmit and receive data
and wake the device from sleep.
• Master sends data — Slave sends dummy data
• Master sends data — Slave sends data
• Master sends dummy data — Slave sends data
FIGURE 11-4: SPI MASTER/SLAVE CONNECTION
SPI Master SSPM3:SSPM0 = 00xxb
SPI Slave SSPM3:SSPM0 = 010xb
SDO
SDI
Serial Input Buffer
(SSPBUF register)
Serial Input Buffer
(SSPBUF register)
SDI
SDO
Shift Register
Shift Register
(SSPSR)
(SSPSR)
LSb
MSb
MSb
LSb
Serial Clock
SCK
SCK
PROCESSOR 1
PROCESSOR 2
1997 Microchip Technology Inc.
DS30390E-page 81
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
The SS pin allows a synchronous slave mode. The
SPI must be in slave mode (SSPCON<3:0> = 04h)
and the TRISA<5> bit must be set the for synchro-
nous slave mode to be enabled. When the SS pin is
low, transmission and reception are enabled and
the SDO pin is driven. When the SS pin goes high,
the SDO pin is no longer driven, even if in the mid-
dle of a transmitted byte, and becomes a floating
output. If the SS pin is taken low without resetting
SPI mode, the transmission will continue from the
point at which it was taken high. External pull-up/
pull-down resistors may be desirable, depending on the
application.
To emulate two-wire communication, the SDO pin can
be connected to the SDI pin. When the SPI needs to
operate as a receiver the SDO pin can be configured as
an input. This disables transmissions from the SDO.
The SDI can always be left as an input (SDI function)
since it cannot create a bus conflict.
FIGURE 11-5: SPI MODE TIMING, MASTER MODE OR SLAVE MODE W/O SS CONTROL
SCK
(CKP = 0)
SCK
(CKP = 1)
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit0
SDO
SDI
bit7
SSPIF
FIGURE 11-6: SPI MODE TIMING, SLAVE MODE WITH SS CONTROL
SS
SCK
(CKP = 0)
SCK
(CKP = 1)
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit0
SDO
SDI
bit7
SSPIF
TABLE 11-1: REGISTERS ASSOCIATED WITH SPI OPERATION
Value on:
POR,
BOR
Value on
all other
resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0Bh,8Bh
0Ch
INTCON
PIR1
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
(1,2)
(2)
(2)
PSPIF
PSPIE
ADIF RCIF
ADIE RCIE
TXIF
TXIE
SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
(1,2)
(2)
(2)
8Ch
87h
PIE1
SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
13h
14h
85h
94h
SSPBUF Synchronous Serial Port Receive Buffer/Transmit Register
xxxx xxxx uuuu uuuu
SSPCON
TRISA
WCOL
—
SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000 0000 0000
—
—
PORTA Data Direction Register
D/A R/W
--11 1111 --11 1111
--00 0000 --00 0000
SSPSTAT
—
P
S
UA
BF
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by the SSP in SPI mode.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A, always maintain these bits clear.
2: The PIC16C72 does not have a Parallel Slave Port or USART, these bits are unimplemented, read as '0'.
DS30390E-page 82
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.3
SPI Mode for PIC16C76/77
This section contains register definitions and opera-
tional characteristics of the SPI module on the
PIC16C76 and PIC16C77 only.
FIGURE 11-7: SSPSTAT: SYNC SERIAL PORT STATUS REGISTER (ADDRESS 94h)(PIC16C76/77)
R/W-0 R/W-0
SMP CKE
bit7
R-0
D/A
R-0
P
R-0
S
R-0
R-0
UA
R-0
BF
R/W
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as ‘0’
bit0
- n =Value at POR reset
bit 7:
bit 6:
SMP: SPI data input sample phase
SPI Master Mode
1 = Input data sampled at end of data output time
0 = Input data sampled at middle of data output time
SPI Slave Mode
SMP must be cleared when SPI is used in slave mode
CKE: SPI Clock Edge Select (Figure 11-11, Figure 11-12, and Figure 11-13)
CKP = 0
1 = Data transmitted on rising edge of SCK
0 = Data transmitted on falling edge of SCK
CKP = 1
1 = Data transmitted on falling edge of SCK
0 = Data transmitted on rising edge of SCK
2
bit 5:
bit 4:
D/A: Data/Address bit (I C mode only)
1 = Indicates that the last byte received or transmitted was data
0 = Indicates that the last byte received or transmitted was address
2
P: Stop bit (I C mode only. This bit is cleared when the SSP module is disabled, or when the Start bit is
detected last, SSPEN is cleared)
1 = Indicates that a stop bit has been detected last (this bit is '0' on RESET)
0 = Stop bit was not detected last
2
bit 3:
bit 2:
S: Start bit (I C mode only. This bit is cleared when the SSP module is disabled, or when the Stop bit is
detected last, SSPEN is cleared)
1 = Indicates that a start bit has been detected last (this bit is '0' on RESET)
0 = Start bit was not detected last
2
R/W: Read/Write bit information (I C mode only)
This bit holds the R/W bit information following the last address match. This bit is only valid from the
address match to the next start bit, stop bit, or ACK bit.
1 = Read
0 = Write
2
bit 1:
bit 0:
UA: Update Address (10-bit I C mode only)
1 = Indicates that the user needs to update the address in the SSPADD register
0 = Address does not need to be updated
BF: Buffer Full Status bit
2
Receive (SPI and I C modes)
1 = Receive complete, SSPBUF is full
0 = Receive not complete, SSPBUF is empty
2
Transmit (I C mode only)
1 = Transmit in progress, SSPBUF is full
0 = Transmit complete, SSPBUF is empty
1997 Microchip Technology Inc.
DS30390E-page 83
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
FIGURE 11-8: SSPCON: SYNC SERIAL PORT CONTROL REGISTER (ADDRESS 14h)(PIC16C76/77)
R/W-0
R/W-0
R/W-0
R/W-0
CKP
R/W-0
R/W-0
R/W-0
R/W-0
WCOL SSPOV SSPEN
bit7
SSPM3 SSPM2 SSPM1 SSPM0
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as ‘0’
- n =Value at POR reset
bit 7:
WCOL: Write Collision Detect bit
1 = The SSPBUF register is written while it is still transmitting the previous word
(must be cleared in software)
0 = No collision
bit 6:
SSPOV: Receive Overflow Indicator bit
In SPI mode
1 = A new byte is received while the SSPBUF register is still holding the previous data. In case of overflow,
the data in SSPSR is lost. Overflow can only occur in slave mode.The user must read the SSPBUF, even
if only transmitting data, to avoid setting overflow. In master mode the overflow bit is not set since each
new reception (and transmission) is initiated by writing to the SSPBUF register.
0 = No overflow
2
In I C mode
1 = A byte is received while the SSPBUF register is still holding the previous byte. SSPOV is a "don’t care"
in transmit mode. SSPOV must be cleared in software in either mode.
0 = No overflow
bit 5:
SSPEN: Synchronous Serial Port Enable bit
In SPI mode
1 = Enables serial port and configures SCK, SDO, and SDI as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
2
In I C mode
1 = Enables the serial port and configures the SDA and SCL pins as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
In both modes, when enabled, these pins must be properly configured as input or output.
bit 4:
CKP: Clock Polarity Select bit
In SPI mode
1 = Idle state for clock is a high level
0 = Idle state for clock is a low level
2
In I C mode
SCK release control
1 = Enable clock
0 = Holds clock low (clock stretch) (Used to ensure data setup time)
bit 3-0: SSPM3:SSPM0: Synchronous Serial Port Mode Select bits
0000= SPI master mode, clock = FOSC/4
0001= SPI master mode, clock = FOSC/16
0010= SPI master mode, clock = FOSC/64
0011= SPI master mode, clock = TMR2 output/2
0100= SPI slave mode, clock = SCK pin. SS pin control enabled.
0101= SPI slave mode, clock = SCK pin. SS pin control disabled. SS can be used as I/O pin
2
0110= I C slave mode, 7-bit address
2
0111= I C slave mode, 10-bit address
2
1011= I C firmware controlled master mode (slave idle)
2
1110= I C slave mode, 7-bit address with start and stop bit interrupts enabled
2
1111= I C slave mode, 10-bit address with start and stop bit interrupts enabled
DS30390E-page 84
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.3.1 SPI MODE FOR PIC16C76/77
EXAMPLE 11-2: LOADING THE SSPBUF
(SSPSR) REGISTER
The SPI mode allows 8-bits of data to be synchro-
nously transmitted and received simultaneously. To
accomplish communication, typically three pins are
used:
(PIC16C76/77)
BCF
BSF
STATUS, RP1
STATUS, RP0
;Specify Bank 1
;
LOOP BTFSS SSPSTAT, BF
;Has data been
;received
;(transmit
;complete)?
;No
;Specify Bank 0
;W reg = contents
; of SSPBUF
;Save in user RAM
• Serial Data Out (SDO) RC5/SDO
• Serial Data In (SDI) RC4/SDI/SDA
• Serial Clock (SCK) RC3/SCK/SCL
GOTO LOOP
Additionally a fourth pin may be used when in a slave
mode of operation:
BCF
STATUS, RP0
MOVF SSPBUF, W
• Slave Select (SS) RA5/SS/AN4
MOVWF RXDATA
When initializing the SPI, several options need to be
specified.This is done by programming the appropriate
control bits in the SSPCON register (SSPCON<5:0>)
and SSPSTAT<7:6>. These control bits allow the fol-
lowing to be specified:
MOVF TXDATA, W
;W reg = contents
; of TXDATA
;New data to xmit
MOVWF SSPBUF
The block diagram of the SSP module, when in SPI
mode (Figure 11-9), shows that the SSPSR is not
directly readable or writable, and can only be accessed
from addressing the SSPBUF register. Additionally, the
SSP status register (SSPSTAT) indicates the various
status conditions.
• Master Mode (SCK is the clock output)
• Slave Mode (SCK is the clock input)
• Clock Polarity (Idle state of SCK)
• Clock edge (output data on rising/falling edge of
SCK)
• Clock Rate (Master mode only)
FIGURE 11-9: SSP BLOCK DIAGRAM
(SPI MODE)(PIC16C76/77)
• Slave Select Mode (Slave mode only)
The SSP consists of a transmit/receive Shift Register
(SSPSR) and a buffer register (SSPBUF). The SSPSR
shifts the data in and out of the device, MSb first. The
SSPBUF holds the data that was written to the SSPSR
until the received data is ready. Once the 8-bits of data
have been received, that byte is moved to the SSPBUF
register. Then the buffer full detect bit BF
(SSPSTAT<0>) and interrupt flag bit SSPIF (PIR1<3>)
are set. This double buffering of the received data
(SSPBUF) allows the next byte to start reception before
reading the data that was just received. Any write to the
SSPBUF register during transmission/reception of data
will be ignored, and the write collision detect bit WCOL
(SSPCON<7>) will be set. User software must clear the
WCOL bit so that it can be determined if the following
write(s) to the SSPBUF register completed success-
fully. When the application software is expecting to
receive valid data, the SSPBUF should be read before
the next byte of data to transfer is written to the
SSPBUF. Buffer full bit BF (SSPSTAT<0>) indicates
when SSPBUF has been loaded with the received data
(transmission is complete). When the SSPBUF is read,
bit BF is cleared. This data may be irrelevant if the SPI
is only a transmitter. Generally the SSP Interrupt is
used to determine when the transmission/reception
has completed.The SSPBUF must be read and/or writ-
ten. If the interrupt method is not going to be used, then
software polling can be done to ensure that a write col-
lision does not occur. Example 11-2 shows the loading
of the SSPBUF (SSPSR) for data transmission. The
shaded instruction is only required if the received data
is meaningful.
Internal
data bus
Read
Write
SSPBUF reg
SSPSR reg
shift
clock
RC4/SDI/SDA
RC5/SDO
bit0
Control
Enable
SS
RA5/SS/AN4
Edge
Select
2
Clock Select
SSPM3:SSPM0
4
TMR2 output
2
Edge
Select
TCY
Prescaler
4, 16, 64
RC3/SCK/
SCL
TRISC<3>
1997 Microchip Technology Inc.
DS30390E-page 85
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
To enable the serial port, SSP Enable bit, SSPEN
(SSPCON<5>) must be set.To reset or reconfigure SPI
mode, clear bit SSPEN, re-initialize the SSPCON reg-
ister, and then set bit SSPEN. This configures the SDI,
SDO, SCK, and SS pins as serial port pins. For the pins
to behave as the serial port function, they must have
their data direction bits (in the TRISC register) appro-
priately programmed. That is:
The master can initiate the data transfer at any time
because it controls the SCK. The master determines
when the slave (Processor 2) is to broadcast data by
the firmware protocol.
In master mode the data is transmitted/received as
soon as the SSPBUF register is written to. If the SPI is
only going to receive, the SCK output could be disabled
(programmed as an input). The SSPSR register will
continue to shift in the signal present on the SDI pin at
the programmed clock rate. As each byte is received, it
will be loaded into the SSPBUF register as if a normal
received byte (interrupts and status bits appropriately
set). This could be useful in receiver applications as a
“line activity monitor” mode.
• SDI must have TRISC<4> set
• SDO must have TRISC<5> cleared
• SCK (Master mode) must have TRISC<3>
cleared
• SCK (Slave mode) must have TRISC<3> set
• SS must have TRISA<5> set
In slave mode, the data is transmitted and received as
the external clock pulses appear on SCK. When the
last bit is latched the interrupt flag bit SSPIF (PIR1<3>)
is set.
Any serial port function that is not desired may be over-
ridden by programming the corresponding data direc-
tion (TRIS) register to the opposite value. An example
would be in master mode where you are only sending
data (to a display driver), then both SDI and SS could
be used as general purpose outputs by clearing their
corresponding TRIS register bits.
The clock polarity is selected by appropriately program-
ming bit CKP (SSPCON<4>). This then would give
waveforms for SPI communication as shown in
Figure 11-11, Figure 11-12, and Figure 11-13 where
the MSB is transmitted first. In master mode, the SPI
clock rate (bit rate) is user programmable to be one of
the following:
Figure 11-10 shows a typical connection between two
microcontrollers. The master controller (Processor 1)
initiates the data transfer by sending the SCK signal.
Data is shifted out of both shift registers on their pro-
grammed clock edge, and latched on the opposite edge
of the clock. Both processors should be programmed to
same Clock Polarity (CKP), then both controllers would
send and receive data at the same time. Whether the
data is meaningful (or dummy data) depends on the
application firmware. This leads to three scenarios for
data transmission:
• FOSC/4 (or TCY)
• FOSC/16 (or 4 • TCY)
• FOSC/64 (or 16 • TCY)
• Timer2 output/2
This allows a maximum bit clock frequency (at 20 MHz)
of 5 MHz. When in slave mode the external clock must
meet the minimum high and low times.
• Master sends data — Slave sends dummy data
• Master sends data — Slave sends data
In sleep mode, the slave can transmit and receive data
and wake the device from sleep.
• Master sends dummy data — Slave sends data
FIGURE 11-10: SPI MASTER/SLAVE CONNECTION (PIC16C76/77)
SPI Master SSPM3:SSPM0 = 00xxb
SPI Slave SSPM3:SSPM0 = 010xb
SDO
SDI
Serial Input Buffer
(SSPBUF)
Serial Input Buffer
(SSPBUF)
SDI
SDO
SCK
Shift Register
(SSPSR)
Shift Register
(SSPSR)
LSb
MSb
MSb
LSb
Serial Clock
SCK
PROCESSOR 1
PROCESSOR 2
DS30390E-page 86
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
The SS pin allows a synchronous slave mode. The
.
SPI must be in slave mode (SSPCON<3:0> = 04h)
and the TRISA<5> bit must be set for the synchro-
nous slave mode to be enabled. When the SS pin is
low, transmission and reception are enabled and
the SDO pin is driven. When the SS pin goes high,
the SDO pin is no longer driven, even if in the mid-
dle of a transmitted byte, and becomes a floating
output. If the SS pin is taken low without resetting
SPI mode, the transmission will continue from the
point at which it was taken high. External pull-up/
pull-down resistors may be desirable, depending on the
application.
Note: When the SPI is in Slave Mode with SS pin
control enabled, (SSPCON<3:0> = 0100)
the SPI module will reset if the SSpin is set
to VDD.
Note: If the SPI is used in Slave Mode with
CKE = '1', then the SS pin control must be
enabled.
To emulate two-wire communication, the SDO pin can
be connected to the SDI pin. When the SPI needs to
operate as a receiver the SDO pin can be configured as
an input. This disables transmissions from the SDO.
The SDI can always be left as an input (SDI function)
since it cannot create a bus conflict.
FIGURE 11-11: SPI MODE TIMING, MASTER MODE (PIC16C76/77)
SCK (CKP = 0,
CKE = 0)
SCK (CKP = 0,
CKE = 1)
SCK (CKP = 1,
CKE = 0)
SCK (CKP = 1,
CKE = 1)
bit2
bit7
bit6
bit5
bit3
bit1
bit0
bit4
SDO
SDI (SMP = 0)
bit7
bit0
SDI (SMP = 1)
SSPIF
bit7
bit0
FIGURE 11-12: SPI MODE TIMING (SLAVE MODE WITH CKE = 0) (PIC16C76/77)
SS (optional)
SCK (CKP = 0)
SCK (CKP = 1)
bit2
bit7
bit6
bit5
bit3
bit1
bit0
bit4
SDO
SDI (SMP = 0)
bit7
bit0
SSPIF
1997 Microchip Technology Inc.
DS30390E-page 87
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
FIGURE 11-13: SPI MODE TIMING (SLAVE MODE WITH CKE = 1) (PIC16C76/77)
SS
(not optional)
SCK (CKP = 0)
SCK (CKP = 1)
bit2
SDO
bit7
bit6
bit5
bit3
bit1
bit0
bit4
SDI (SMP = 0)
SSPIF
bit7
bit0
TABLE 11-2: REGISTERS ASSOCIATED WITH SPI OPERATION (PIC16C76/77)
Value on:
POR,
BOR
Value on
all other
resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0Bh,8Bh.
10Bh,18Bh
INTCON
PIR1
GIE
PEIE
T0IE
INTE RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
(1)
0Ch
PSPIF
PSPIE
ADIF
ADIE
RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
(1)
8Ch
87h
PIE1
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
xxxx xxxx uuuu uuuu
13h
14h
85h
94h
SSPBUF Synchronous Serial Port Receive Buffer/Transmit Register
SSPCON WCOL
SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000 0000 0000
TRISA
—
—
PORTA Data Direction Register
D/A R/W
--11 1111 --11 1111
0000 0000 0000 0000
SSPSTAT
SMP
CKE
P
S
UA
BF
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used by the SSP in SPI mode.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C76, always maintain these bits clear.
DS30390E-page 88
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
2
In both cases the master generates the clock signal.
11.4
I C™ Overview
The output stages of the clock (SCL) and data (SDA)
lines must have an open-drain or open-collector in
order to perform the wired-AND function of the bus.
External pull-up resistors are used to ensure a high
level when no device is pulling the line down. The num-
ber of devices that may be attached to the I C bus is
limited only by the maximum bus loading specification
of 400 pF.
This section provides an overview of the Inter-Inte-
2
grated Circuit (I C) bus, with Section 11.5 discussing
2
the operation of the SSP module in I C mode.
2
The I C bus is a two-wire serial interface developed by
2
the Philips Corporation. The original specification, or
standard mode, was for data transfers of up to 100
Kbps. The enhanced specification (fast mode) is also
supported. This device will communicate with both
standard and fast mode devices if attached to the same
bus. The clock will determine the data rate.
11.4.1 INITIATING AND TERMINATING DATA
TRANSFER
2
The I C interface employs a comprehensive protocol to
During times of no data transfer (idle time), both the
clock line (SCL) and the data line (SDA) are pulled high
through the external pull-up resistors. The START and
STOP conditions determine the start and stop of data
transmission.The START condition is defined as a high
to low transition of the SDA when the SCL is high. The
STOP condition is defined as a low to high transition of
the SDA when the SCL is high. Figure 11-14 shows the
START and STOP conditions. The master generates
these conditions for starting and terminating data trans-
fer. Due to the definition of the START and STOP con-
ditions, when data is being transmitted, the SDA line
can only change state when the SCL line is low.
ensure reliable transmission and reception of data.
When transmitting data, one device is the “master”
which initiates transfer on the bus and generates the
clock signals to permit that transfer, while the other
device(s) acts as the “slave.” All portions of the slave
protocol are implemented in the SSP module’s hard-
ware, except general call support, while portions of the
master protocol need to be addressed in the
PIC16CXX software. Table 11-3 defines some of the
I C bus terminology. For additional information on the
I C interface specification, refer to the Philips docu-
ment “The I C bus and how to use it.”#939839340011,
which can be obtained from the Philips Corporation.
2
2
2
2
In the I C interface protocol each device has an
FIGURE 11-14: START AND STOP
CONDITIONS
address. When a master wishes to initiate a data trans-
fer, it first transmits the address of the device that it
wishes to “talk” to. All devices “listen” to see if this is
their address. Within this address, a bit specifies if the
master wishes to read-from/write-to the slave device.
The master and slave are always in opposite modes
(transmitter/receiver) of operation during a data trans-
fer.That is they can be thought of as operating in either
of these two relations:
SDA
S
SCL
P
Change
of Data
Allowed
Change
of Data
Allowed
Start
Condition
Stop
Condition
• Master-transmitter and Slave-receiver
• Slave-transmitter and Master-receiver
2
TABLE 11-3: I C BUS TERMINOLOGY
Term
Description
Transmitter
Receiver
Master
The device that sends the data to the bus.
The device that receives the data from the bus.
The device which initiates the transfer, generates the clock and terminates the transfer.
The device addressed by a master.
Slave
Multi-master
More than one master device in a system. These masters can attempt to control the bus at the
same time without corrupting the message.
Arbitration
Procedure that ensures that only one of the master devices will control the bus. This ensure that
the transfer data does not get corrupted.
Synchronization
Procedure where the clock signals of two or more devices are synchronized.
1997 Microchip Technology Inc.
DS30390E-page 89
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
2
11.4.2 ADDRESSING I C DEVICES
FIGURE 11-17: SLAVE-RECEIVER
ACKNOWLEDGE
There are two address formats. The simplest is the
7-bit address format with a R/W bit (Figure 11-15). The
more complex is the 10-bit address with a R/W bit
(Figure 11-16). For 10-bit address format, two bytes
must be transmitted with the first five bits specifying this
to be a 10-bit address.
Data
Output by
Transmitter
Data
Output by
Receiver
not acknowledge
acknowledge
SCL from
Master
9
8
2
1
FIGURE 11-15: 7-BIT ADDRESS FORMAT
S
MSb
LSb
Clock Pulse for
Acknowledgment
Start
Condition
R/W ACK
S
slave address
Sent by
Slave
If the master is receiving the data (master-receiver), it
generates an acknowledge signal for each received
byte of data, except for the last byte. To signal the end
of data to the slave-transmitter, the master does not
generate an acknowledge (not acknowledge). The
slave then releases the SDA line so the master can
generate the STOP condition. The master can also
generate the STOP condition during the acknowledge
pulse for valid termination of data transfer.
S
R/W
ACK
Start Condition
Read/Write pulse
Acknowledge
2
FIGURE 11-16: I C 10-BIT ADDRESS FORMAT
S
1 1 1 1 0 A9 A8 R/W ACK A7 A6 A5 A4 A3 A2 A1 A0 ACK
sent by slave
If the slave needs to delay the transmission of the next
byte, holding the SCL line low will force the master into
a wait state. Data transfer continues when the slave
releases the SCL line.This allows the slave to move the
received data or fetch the data it needs to transfer
before allowing the clock to start. This wait state tech-
nique can also be implemented at the bit level,
Figure 11-18.The slave will inherently stretch the clock,
when it is a transmitter, but will not when it is a receiver.
The slave will have to clear the SSPCON<4> bit to
enable clock stretching when it is a receiver.
= 0 for write
S
- Start Condition
R/W - Read/Write Pulse
ACK - Acknowledge
11.4.3 TRANSFER ACKNOWLEDGE
All data must be transmitted per byte, with no limit to the
number of bytes transmitted per data transfer. After
each byte, the slave-receiver generates an acknowl-
edge bit (ACK) (Figure 11-17). When a slave-receiver
doesn’t acknowledge the slave address or received
data, the master must abort the transfer. The slave
must leave SDA high so that the master can generate
the STOP condition (Figure 11-14).
FIGURE 11-18: DATA TRANSFER WAIT STATE
SDA
MSB
acknowledgment
signal from receiver
acknowledgment
signal from receiver
byte complete
interrupt with receiver
clock line held low while
interrupts are serviced
SCL
S
1
2
7
8
9
1
2
3 • 8
9
P
Start
Condition
Stop
Condition
Address
R/W ACK Wait
State
Data
ACK
DS30390E-page 90
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
Figure 11-19 and Figure 11-20 show Master-transmit-
ter and Master-receiver data transfer sequences.
SCL is high), but occurs after a data transfer acknowl-
edge pulse (not the bus-free state). This allows a mas-
ter to send “commands” to the slave and then receive
the requested information or to address a different
slave device. This sequence is shown in Figure 11-21.
When a master does not wish to relinquish the bus (by
generating a STOP condition), a repeated START con-
dition (Sr) must be generated. This condition is identi-
cal to the start condition (SDA goes high-to-low while
FIGURE 11-19: MASTER-TRANSMITTER SEQUENCE
For 7-bit address:
For 10-bit address:
S Slave AddressR/W A1Slave Address A2
S Slave Address R/W A Data A Data A/A P
First 7 bits
Second byte
'0' (write)
data transferred
(n bytes - acknowledge)
(write)
A master transmitter addresses a slave receiver with a
7-bit address. The transfer direction is not changed.
Data A
Data A/A P
A = acknowledge (SDA low)
A = not acknowledge (SDA high)
From master to slave
S = Start Condition
A master transmitter addresses a slave receiver
with a 10-bit address.
From slave to master
P = Stop Condition
FIGURE 11-20: MASTER-RECEIVER SEQUENCE
For 10-bit address:
S Slave AddressR/W A1Slave Address A2
First 7 bits Second byte
(write)
For 7-bit address:
S Slave Address R/W A Data A Data A
P
'1' (read) data transferred
(n bytes - acknowledge)
A master reads a slave immediately after the first byte.
SrSlave AddressR/W A3 Data A Data A P
First 7 bits
A = acknowledge (SDA low)
A = not acknowledge (SDA high)
From master to slave
(read)
S = Start Condition
A master transmitter addresses a slave receiver
with a 10-bit address.
From slave to master
P = Stop Condition
FIGURE 11-21: COMBINED FORMAT
(read or write)
(n bytes + acknowledge)
S Slave Address R/W A Data A/A Sr Slave Address R/W A Data A/A P
(write)
Direction of transfer
may change at this point
(read)
Sr = repeated
Start Condition
Transfer direction of data and acknowledgment bits depends on R/Wbits.
Combined format:
SrSlave Address R/W A Slave Address A Data A
First 7 bits Second byte
Data A/A Sr Slave Address R/W A Data A
First 7 bits
Data A P
(read)
(write)
Combined format - A master addresses a slave with a 10-bit address, then transmits
data to this slave and reads data from this slave.
A = acknowledge (SDA low)
A = not acknowledge (SDA high)
From master to slave
S = Start Condition
From slave to master
P = Stop Condition
1997 Microchip Technology Inc.
DS30390E-page 91
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.4.4 MULTI-MASTER
11.2.4.2 Clock Synchronization
Clock synchronization occurs after the devices have
started arbitration. This is performed using
2
The I C protocol allows a system to have more than
a
one master. This is called multi-master. When two or
more masters try to transfer data at the same time, arbi-
tration and synchronization occur.
wired-AND connection to the SCL line. A high to low
transition on the SCL line causes the concerned
devices to start counting off their low period. Once a
device clock has gone low, it will hold the SCL line low
until its SCL high state is reached.The low to high tran-
sition of this clock may not change the state of the SCL
line, if another device clock is still within its low period.
The SCL line is held low by the device with the longest
low period. Devices with shorter low periods enter a
high wait-state, until the SCL line comes high. When
the SCL line comes high, all devices start counting off
their high periods. The first device to complete its high
period will pull the SCL line low.The SCL line high time
is determined by the device with the shortest high
period, Figure 11-23.
11.4.4.1 ARBITRATION
Arbitration takes place on the SDA line, while the SCL
line is high. The master which transmits a high when
the other master transmits a low loses arbitration
(Figure 11-22), and turns off its data output stage. A
master which lost arbitration can generate clock pulses
until the end of the data byte where it lost arbitration.
When the master devices are addressing the same
device, arbitration continues into the data.
FIGURE 11-22: MULTI-MASTER
ARBITRATION
(TWO MASTERS)
FIGURE 11-23: CLOCK SYNCHRONIZATION
transmitter 1 loses arbitration
DATA 1 SDA
start counting
HIGH period
wait
state
DATA 1
DATA 2
SDA
CLK
1
counter
reset
CLK
2
SCL
SCL
Masters that also incorporate the slave function, and
have lost arbitration must immediately switch over to
slave-receiver mode. This is because the winning mas-
ter-transmitter may be addressing it.
Arbitration is not allowed between:
• A repeated START condition
• A STOP condition and a data bit
• A repeated START condition and a STOP condi-
tion
Care needs to be taken to ensure that these conditions
do not occur.
DS30390E-page 92
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
2
2
The SSPCON register allows control of the I C opera-
tion. Four mode selection bits (SSPCON<3:0>) allow
11.5
SSP I C Operation
2
2
The SSP module in I C mode fully implements all slave
functions, except general call support, and provides
interrupts on start and stop bits in hardware to facilitate
firmware implementations of the master functions. The
SSP module implements the standard mode specifica-
tions as well as 7-bit and 10-bit addressing. Two pins
are used for data transfer. These are the
RC3/SCK/SCL pin, which is the clock (SCL), and the
RC4/SDI/SDA pin, which is the data (SDA). The user
must configure these pins as inputs or outputs through
the TRISC<4:3> bits. The SSP module functions are
enabled by setting SSP Enable bit SSPEN (SSP-
CON<5>).
one of the following I C modes to be selected:
2
• I C Slave mode (7-bit address)
2
• I C Slave mode (10-bit address)
2
• I C Slave mode (7-bit address), with start and
stop bit interrupts enabled
2
• I C Slave mode (10-bit address), with start and
stop bit interrupts enabled
2
• I C Firmware controlled Master Mode, slave is
idle
2
Selection of any I C mode, with the SSPEN bit set,
forces the SCL and SDA pins to be open drain, pro-
vided these pins are programmed to inputs by setting
the appropriate TRISC bits.
FIGURE 11-24: SSP BLOCK DIAGRAM
2
The SSPSTAT register gives the status of the data
transfer. This information includes detection of a
START or STOP bit, specifies if the received byte was
data or address if the next byte is the completion of
10-bit address, and if this will be a read or write data
transfer. The SSPSTAT register is read only.
(I C MODE)
Internal
data bus
Read
Write
The SSPBUF is the register to which transfer data is
written to or read from. The SSPSR register shifts the
data in or out of the device. In receive operations, the
SSPBUF and SSPSR create a doubled buffered
receiver. This allows reception of the next byte to begin
before reading the last byte of received data. When the
complete byte is received, it is transferred to the
SSPBUF register and flag bit SSPIF is set. If another
complete byte is received before the SSPBUF register
is read, a receiver overflow has occurred and bit
SSPOV (SSPCON<6>) is set and the byte in the
SSPSR is lost.
SSPBUF reg
SSPSR reg
RC3/SCK/SCL
shift
clock
RC4/
SDI/
SDA
MSb
LSb
Addr Match
Match detect
SSPADD reg
The SSPADD register holds the slave address. In 10-bit
mode, the user first needs to write the high byte of the
address (1111 0 A9 A8 0). Following the high byte
address match, the low byte of the address needs to be
loaded (A7:A0).
Set, Reset
S, P bits
Start and
Stop bit detect
(SSPSTAT reg)
2
The SSP module has five registers for I C operation.
These are the:
• SSP Control Register (SSPCON)
• SSP Status Register (SSPSTAT)
• Serial Receive/Transmit Buffer (SSPBUF)
• SSP Shift Register (SSPSR) - Not directly acces-
sible
• SSP Address Register (SSPADD)
1997 Microchip Technology Inc.
DS30390E-page 93
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.5.1 SLAVE MODE
address is compared on the falling edge of the eighth
clock (SCL) pulse. If the addresses match, and the BF
and SSPOV bits are clear, the following events occur:
In slave mode, the SCL and SDA pins must be config-
ured as inputs (TRISC<4:3> set). The SSP module will
override the input state with the output data when
required (slave-transmitter).
a) The SSPSR register value is loaded into the
SSPBUF register.
b) The buffer full bit, BF is set.
c) An ACK pulse is generated.
When an address is matched or the data transfer after
an address match is received, the hardware automati-
cally will generate the acknowledge (ACK) pulse, and
then load the SSPBUF register with the received value
currently in the SSPSR register.
d) SSP interrupt flag bit, SSPIF (PIR1<3>) is set
(interrupt is generated if enabled) - on the falling
edge of the ninth SCL pulse.
In 10-bit address mode, two address bytes need to be
received by the slave (Figure 11-16).The five Most Sig-
nificant bits (MSbs) of the first address byte specify if
this is a 10-bit address. Bit R/W (SSPSTAT<2>) must
specify a write so the slave device will receive the sec-
ond address byte. For a 10-bit address the first byte
would equal ‘1111 0 A9 A8 0’, where A9 and A8 are
the two MSbs of the address. The sequence of events
for 10-bit address is as follows, with steps 7- 9 for
slave-transmitter:
There are certain conditions that will cause the SSP
module not to give this ACK pulse. These are if either
(or both):
a) The buffer full bit BF (SSPSTAT<0>) was set
before the transfer was received.
b) The overflow bit SSPOV (SSPCON<6>) was set
before the transfer was received.
In this case, the SSPSR register value is not loaded
into the SSPBUF, but bit SSPIF (PIR1<3>) is set.
Table 11-4 shows what happens when a data transfer
byte is received, given the status of bits BF and SSPOV.
The shaded cells show the condition where user soft-
ware did not properly clear the overflow condition. Flag
bit BF is cleared by reading the SSPBUF register while
bit SSPOV is cleared through software.
1. Receive first (high) byte of Address (bits SSPIF,
BF, and bit UA (SSPSTAT<1>) are set).
2. Update the SSPADD register with second (low)
byte of Address (clears bit UA and releases the
SCL line).
3. Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
The SCL clock input must have a minimum high and
low for proper operation. The high and low times of the
4. Receive second (low) byte of Address (bits
SSPIF, BF, and UA are set).
2
I C specification as well as the requirement of the SSP
module is shown in timing parameter #100 and param-
eter #101.
5. Update the SSPADD register with the first (high)
byte of Address, if match releases SCL line, this
will clear bit UA.
11.5.1.1 ADDRESSING
6. Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
Once the SSP module has been enabled, it waits for a
START condition to occur. Following the START condi-
tion, the 8-bits are shifted into the SSPSR register. All
incoming bits are sampled with the rising edge of the
clock (SCL) line. The value of register SSPSR<7:1> is
compared to the value of the SSPADD register. The
7. Receive repeated START condition.
8. Receive first (high) byte of Address (bits SSPIF
and BF are set).
9. Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
TABLE 11-4: DATA TRANSFER RECEIVED BYTE ACTIONS
Status Bits as Data
Transfer is Received
Set bit SSPIF
(SSP Interrupt occurs
if enabled)
Generate ACK
Pulse
BF
SSPOV
SSPSR → SSPBUF
0
1
1
0
0
0
1
1
Yes
No
No
No
Yes
No
No
No
Yes
Yes
Yes
Yes
DS30390E-page 94
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.5.1.2 RECEPTION
An SSP interrupt is generated for each data transfer
byte. Flag bit SSPIF (PIR1<3>) must be cleared in soft-
ware. The SSPSTAT register is used to determine the
status of the byte.
When the R/W bit of the address byte is clear and an
address match occurs, the R/Wbit of the SSPSTAT reg-
ister is cleared.The received address is loaded into the
SSPBUF register.
When the address byte overflow condition exists, then
no acknowledge (ACK) pulse is given. An overflow con-
dition is defined as either bit BF (SSPSTAT<0>) is set
or bit SSPOV (SSPCON<6>) is set.
2
FIGURE 11-25: I C WAVEFORMS FOR RECEPTION (7-BIT ADDRESS)
Receiving Address
A7 A6 A5 A4
R/W=0
Receiving Data
Receiving Data
ACK
9
ACK
9
ACK
9
SDA
SCL
A3 A2 A1
D5
D2
D0
8
D5
D2
D0
8
D7 D6
D4 D3
D7 D6
D4 D3
D1
7
D1
7
3
7
1
2
4
5
4
3
6
5
6
1
2
3
6
1
2
4
8
5
P
S
SSPIF (PIR1<3>)
Cleared in software
Bus Master
terminates
transfer
BF (SSPSTAT<0>)
SSPBUF register is read
SSPOV (SSPCON<6>)
Bit SSPOV is set because the SSPBUF register is still full.
ACK is not sent.
1997 Microchip Technology Inc.
DS30390E-page 95
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.5.1.3 TRANSMISSION
An SSP interrupt is generated for each data transfer
byte. Flag bit SSPIF must be cleared in software, and
the SSPSTAT register is used to determine the status
of the byte. Flag bit SSPIF is set on the falling edge of
the ninth clock pulse.
When the R/W bit of the incoming address byte is set
and an address match occurs, the R/W bit of the
SSPSTAT register is set. The received address is
loaded into the SSPBUF register. The ACK pulse will
be sent on the ninth bit, and pin RC3/SCK/SCL is held
low. The transmit data must be loaded into the SSP-
BUF register, which also loads the SSPSR register.
Then pin RC3/SCK/SCL should be enabled by setting
bit CKP (SSPCON<4>). The master must monitor the
SCL pin prior to asserting another clock pulse. The
slave devices may be holding off the master by stretch-
ing the clock. The eight data bits are shifted out on the
falling edge of the SCL input.This ensures that the SDA
signal is valid during the SCL high time (Figure 11-26).
As a slave-transmitter, the ACK pulse from the mas-
ter-receiver is latched on the rising edge of the ninth
SCL input pulse. If the SDA line was high (not ACK),
then the data transfer is complete. When the ACK is
latched by the slave, the slave logic is reset (resets
SSPSTAT register) and the slave then monitors for
another occurrence of the START bit. If the SDA line
was low (ACK), the transmit data must be loaded into
the SSPBUF register, which also loads the SSPSR reg-
ister. Then pin RC3/SCK/SCL should be enabled by
setting bit CKP.
2
FIGURE 11-26: I C WAVEFORMS FOR TRANSMISSION (7-BIT ADDRESS)
Receiving Address
R/W = 1
ACK
Transmitting Data
ACK
9
SDA
SCL
A7 A6 A5 A4 A3 A2 A1
D7 D6 D5 D4 D3 D2 D1 D0
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
S
P
SCL held low
while CPU
responds to SSPIF
Data in
sampled
cleared in software
SSPIF (PIR1<3>)
BF (SSPSTAT<0>)
From SSP interrupt
service routine
SSPBUF is written in software
CKP (SSPCON<4>)
Set bit after writing to SSPBUF
(the SSPBUF must be written-to
before the CKP bit can be set)
DS30390E-page 96
1997 Microchip Technology Inc.
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
11.5.2 MASTER MODE
11.5.3 MULTI-MASTER MODE
Master mode of operation is supported in firmware
using interrupt generation on the detection of the
START and STOP conditions. The STOP (P) and
START (S) bits are cleared from a reset or when the
SSP module is disabled.The STOP (P) and START (S)
bits will toggle based on the START and STOP condi-
In multi-master mode, the interrupt generation on the
detection of the START and STOP conditions allows
the determination of when the bus is free. The STOP
(P) and START (S) bits are cleared from a reset or
when the SSP module is disabled. The STOP (P) and
START (S) bits will toggle based on the START and
2
2
tions. Control of the I C bus may be taken when the P
STOP conditions. Control of the I C bus may be taken
bit is set, or the bus is idle and both the S and P bits are
clear.
when bit P (SSPSTAT<4>) is set, or the bus is idle and
both the S and P bits clear. When the bus is busy,
enabling the SSP Interrupt will generate the interrupt
when the STOP condition occurs.
In master mode the SCL and SDA lines are manipu-
lated by clearing the corresponding TRISC<4:3> bit(s).
The output level is always low, irrespective of the
value(s) in PORTC<4:3>. So when transmitting data, a
'1' data bit must have the TRISC<4> bit set (input) and
a '0' data bit must have the TRISC<4> bit cleared (out-
put).The same scenario is true for the SCL line with the
TRISC<3> bit.
In multi-master operation, the SDA line must be moni-
tored to see if the signal level is the expected output
level. This check only needs to be done when a high
level is output. If a high level is expected and a low level
is present, the device needs to release the SDA and
SCL lines (set TRISC<4:3>). There are two stages
where this arbitration can be lost, these are:
The following events will cause SSP Interrupt Flag bit,
SSPIF, to be set (SSP Interrupt if enabled):
• Address Transfer
• Data Transfer
• START condition
• STOP condition
When the slave logic is enabled, the slave continues to
receive. If arbitration was lost during the address trans-
fer stage, communication to the device may be in
progress. If addressed an ACK pulse will be generated.
If arbitration was lost during the data transfer stage, the
device will need to re-transfer the data at a later time.
• Data transfer byte transmitted/received
Master mode of operation can be done with either the
slave mode idle (SSPM3:SSPM0 = 1011) or with the
slave active. When both master and slave modes are
enabled, the software needs to differentiate the
source(s) of the interrupt.
2
TABLE 11-5: REGISTERS ASSOCIATED WITH I C OPERATION
Value on
POR,
BOR
Value on all
other resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0000 000x
0000 000u
0Bh, 8Bh,
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
10Bh,18Bh
(1)
PIR1
PIE1
PSPIF
PSPIE
ADIF
ADIE
RCIF
RCIE
TXIF
TXIE
SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
0Ch
8Ch
13h
93h
14h
94h
87h
(1)
xxxx xxxx
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
0000 0000
SSPBUF Synchronous Serial Port Receive Buffer/Transmit Register
2
SSPADD Synchronous Serial Port (I C mode) Address Register
SSPCON
WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0
(2)
(2)
SSPSTAT SMP
CKE
D/A
P
S
R/W
UA
BF
PORTC Data Direction register
TRISC
1111 1111
1111 1111
Legend: x= unknown, u= unchanged, -= unimplemented locations read as '0'.
Shaded cells are not used by SSP module in SPI mode.
Note 1: PSPIF and PSPIE are reserved on the PIC16C73/73A/76, always maintain these bits clear.
2: The SMP and CKE bits are implemented on the PIC16C76/77 only. All other PIC16C7X devices have these two bits unim-
plemented, read as '0'.
1997 Microchip Technology Inc.
DS30390E-page 97
Applicable Devices
PIC16C7X
72 73 73A 74 74A 76 77
2
FIGURE 11-27: OPERATION OF THE I C MODULE IN IDLE_MODE, RCV_MODE OR XMIT_MODE
IDLE_MODE (7-bit):
if (Addr_match)
{
Set interrupt;
if (R/W = 1)
{
}
Send ACK = 0;
set XMIT_MODE;
else if (R/W = 0) set RCV_MODE;
}
RCV_MODE:
if ((SSPBUF=Full) OR (SSPOV = 1))
{
Set SSPOV;
Do not acknowledge;
}
{
else
transfer SSPSR → SSPBUF;
send ACK = 0;
}
Receive 8-bits in SSPSR;
Set interrupt;
XMIT_MODE:
While ((SSPBUF = Empty) AND (CKP=0)) Hold SCL Low;
Send byte;
Set interrupt;
if ( ACK Received = 1)
{
}
End of transmission;
Go back to IDLE_MODE;
else if ( ACK Received = 0) Go back to XMIT_MODE;
IDLE_MODE (10-Bit):
If (High_byte_addr_match AND (R/W = 0))
{
PRIOR_ADDR_MATCH = FALSE;
Set interrupt;
if ((SSPBUF = Full) OR ((SSPOV = 1))
{
Set SSPOV;
Do not acknowledge;
}
{
else
Set UA = 1;
Send ACK = 0;
While (SSPADD not updated) Hold SCL low;
Clear UA = 0;
Receive Low_addr_byte;
Set interrupt;
Set UA = 1;
If (Low_byte_addr_match)
{
PRIOR_ADDR_MATCH = TRUE;
Send ACK = 0;
while (SSPADD not updated) Hold SCL low;
Clear UA = 0;
Set RCV_MODE;
}
}
}
else if (High_byte_addr_match AND (R/W = 1)
if (PRIOR_ADDR_MATCH)
{
{
send ACK = 0;
set XMIT_MODE;
}
else PRIOR_ADDR_MATCH = FALSE;
}
DS30390E-page 98
1997 Microchip Technology Inc.
PIC16C7X
as a half duplex synchronous system that can commu-
nicate with peripheral devices such as A/D or D/A inte-
grated circuits, Serial EEPROMs etc.
12.0 UNIVERSAL SYNCHRONOUS
ASYNCHRONOUS RECEIVER
TRANSMITTER (USART)
Applicable Devices
The USART can be configured in the following modes:
• Asynchronous (full duplex)
72 73 73A 74 74A 76 77
• Synchronous - Master (half duplex)
• Synchronous - Slave (half duplex)
The Universal Synchronous Asynchronous Receiver
Transmitter (USART) module is one of the two serial
I/O modules. (USART is also known as a Serial Com-
munications Interface or SCI). The USART can be con-
figured as a full duplex asynchronous system that can
communicate with peripheral devices such as CRT ter-
minals and personal computers, or it can be configured
Bit SPEN (RCSTA<7>), and bits TRISC<7:6>, have to
be set in order to configure pins RC6/TX/CK and RC7/
RX/DT as the Universal Synchronous Asynchronous
Receiver Transmitter.
FIGURE 12-1: TXSTA:TRANSMIT STATUS AND CONTROL REGISTER (ADDRESS 98h)
R/W-0
CSRC
R/W-0
TX9
R/W-0
TXEN
R/W-0
SYNC
U-0
—
R/W-0
BRGH
R-1
R/W-0
TX9D
TRMT
R = Readable bit
W = Writable bit
bit7
bit0
U = Unimplemented bit,
read as ‘0’
- n =Value at POR reset
bit 7:
CSRC: Clock Source Select bit
Asynchronous mode
Don’t care
Synchronous mode
1 = Master mode (Clock generated internally from BRG)
0 = Slave mode (Clock from external source)
bit 6:
TX9: 9-bit Transmit Enable bit
1 = Selects 9-bit transmission
0 = Selects 8-bit transmission
bit 5:
TXEN: Transmit Enable bit
1 = Transmit enabled
0 = Transmit disabled
Note: SREN/CREN overrides TXEN in SYNC mode.
bit 4:
SYNC: USART Mode Select bit
1 = Synchronous mode
0 = Asynchronous mode
bit 3:
bit 2:
Unimplemented: Read as '0'
BRGH: High Baud Rate Select bit
Asynchronous mode
1 = High speed
Note: For the PIC16C73/73A/74/74A, the asynchronous high speed mode (BRGH = 1) may expe-
rience a high rate of receive errors. It is recommended that BRGH = 0. If you desire a higher
baud rate than BRGH = 0 can support, refer to the device errata for additional information,
or use the PIC16C76/77.
0 = Low speed
Synchronous mode
Unused in this mode
bit 1:
bit 0:
TRMT: Transmit Shift Register Status bit
1 = TSR empty
0 = TSR full
TX9D: 9th bit of transmit data. Can be parity bit.
1997 Microchip Technology Inc.
DS30390E-page 99
PIC16C7X
FIGURE 12-2: RCSTA: RECEIVE STATUS AND CONTROL REGISTER (ADDRESS 18h)
R/W-0
SPEN
R/W-0
RX9
R/W-0
SREN
R/W-0
CREN
U-0
—
R-0
R-0
R-x
FERR
OERR
RX9D
R = Readable bit
W = Writable bit
bit7
bit0
U = Unimplemented bit,
read as ‘0’
- n =Value at POR reset
bit 7:
bit 6:
bit 5:
SPEN: Serial Port Enable bit
1 = Serial port enabled (Configures RC7/RX/DT and RC6/TX/CK pins as serial port pins)
0 = Serial port disabled
RX9: 9-bit Receive Enable bit
1 = Selects 9-bit reception
0 = Selects 8-bit reception
SREN: Single Receive Enable bit
Asynchronous mode
Don’t care
Synchronous mode - master
1 = Enables single receive
0 = Disables single receive
This bit is cleared after reception is complete.
Synchronous mode - slave
Unused in this mode
bit 4:
CREN: Continuous Receive Enable bit
Asynchronous mode
1 = Enables continuous receive
0 = Disables continuous receive
Synchronous mode
1 = Enables continuous receive until enable bit CREN is cleared (CREN overrides SREN)
0 = Disables continuous receive
bit 3:
bit 2:
Unimplemented: Read as '0'
FERR: Framing Error bit
1 = Framing error (Can be updated by reading RCREG register and receive next valid byte)
0 = No framing error
bit 1:
bit 0:
OERR: Overrun Error bit
1 = Overrun error (Can be cleared by clearing bit CREN)
0 = No overrun error
RX9D: 9th bit of received data (Can be parity bit)
DS30390E-page 100
1997 Microchip Technology Inc.
PIC16C7X
12.1
USART Baud Rate Generator (BRG)
Applicable Devices
EXAMPLE 12-1: CALCULATING BAUD
RATE ERROR
72 73 73A 74 74A 76 77
Desired Baud rate = Fosc / (64 (X + 1))
9600
X
=
=
16000000 /(64 (X + 1))
25.042 = 25
The BRG supports both the Asynchronous and Syn-
chronous modes of the USART. It is a dedicated 8-bit
baud rate generator. The SPBRG register controls the
period of a free running 8-bit timer. In asynchronous
mode bit BRGH (TXSTA<2>) also controls the baud
rate. In synchronous mode bit BRGH is ignored.
Table 12-1 shows the formula for computation of the
baud rate for different USART modes which only apply
in master mode (internal clock).
Calculated Baud Rate=16000000 / (64 (25 + 1))
=
=
9615
Error
(Calculated Baud Rate - Desired Baud Rate)
Desired Baud Rate
=
=
(9615 - 9600) / 9600
0.16%
Given the desired baud rate and Fosc, the nearest inte-
ger value for the SPBRG register can be calculated
using the formula in Table 12-1. From this, the error in
baud rate can be determined.
It may be advantageous to use the high baud rate
(BRGH = 1) even for slower baud clocks. This is
because the FOSC/(16(X + 1)) equation can reduce the
baud rate error in some cases.
Example 12-1 shows the calculation of the baud rate
error for the following conditions:
Note: For the PIC16C73/73A/74/74A, the asyn-
chronous high speed mode (BRGH = 1)
may experience a high rate of receive
errors. It is recommended that BRGH = 0.
If you desire a higher baud rate than
BRGH = 0 can support, refer to the device
errata for additional information, or use the
PIC16C76/77.
FOSC = 16 MHz
Desired Baud Rate = 9600
BRGH = 0
SYNC = 0
Writing a new value to the SPBRG register, causes the
BRG timer to be reset (or cleared), this ensures the
BRG does not wait for a timer overflow before output-
ting the new baud rate.
TABLE 12-1: BAUD RATE FORMULA
SYNC
BRGH = 0 (Low Speed)
BRGH = 1 (High Speed)
0
1
(Asynchronous) Baud Rate = FOSC/(64(X+1))
(Synchronous) Baud Rate = FOSC/(4(X+1))
Baud Rate= FOSC/(16(X+1))
NA
X = value in SPBRG (0 to 255)
TABLE 12-2: REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Value on:
POR,
BOR
Value on all
other resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4 Bit 3 Bit 2
Bit 1
Bit 0
0000 -010 0000 -010
98h
TXSTA
CSRC TX9 TXEN SYNC
—
—
BRGH TRMT TX9D
FERR OERR RX9D
0000 -00x 0000 -00x
0000 0000 0000 0000
18h
99h
RCSTA SPEN RX9 SREN CREN
SPBRG Baud Rate Generator Register
Legend: x = unknown, -= unimplemented read as '0'. Shaded cells are not used by the BRG.
1997 Microchip Technology Inc.
DS30390E-page 101
PIC16C7X
TABLE 12-3: BAUD RATES FOR SYNCHRONOUS MODE
FOSC = 20 MHz
16 MHz
KBAUD
10 MHz
KBAUD
7.15909 MHz
KBAUD
BAUD
RATE
(K)
SPBRG
value
SPBRG
value
ERROR (decimal)
SPBRG
value
ERROR (decimal)
SPBRG
value
ERROR (decimal)
%
%
%
%
KBAUD
ERROR (decimal)
0.3
1.2
2.4
NA
NA
NA
-
-
-
-
-
-
NA
NA
NA
-
-
-
-
-
-
NA
NA
NA
-
-
-
-
-
-
NA
NA
NA
-
-
-
-
-
-
9.6
NA
-
+1.73
+0.16
+0.16
-1.96
0
-
NA
-
+0.16
+0.16
-0.79
+2.56
0
-
9.766
19.23
75.76
96.15
312.5
500
+1.73
+0.16
-1.36
+0.16
+4.17
0
255
129
32
25
7
4
0
255
9.622
19.24
77.82
94.20
298.3
NA
+0.23
+0.23
+1.32
-1.88
-0.57
-
185
92
22
18
5
-
0
255
19.2
76.8
96
300
500
HIGH
LOW
19.53
76.92
96.15
294.1
500
255
64
51
16
9
19.23
76.92
95.24
307.69
500
207
51
41
12
7
5000
19.53
-
-
0
255
4000
15.625
-
-
0
255
2500
9.766
-
-
1789.8
6.991
-
-
FOSC = 5.0688 MHz
SPBRG
4 MHz
3.579545 MHz
1 MHz
32.768 kHz
BAUD
SPBRG
value
ERROR (decimal)
SPBRG
value KBAUD
ERROR (decimal)
SPBRG
SPBRG
value
RATE KBAUD
(K)
%
value KBAUD
%
KBAUD
%
%
value KBAUD
%
ERROR (decimal)
ERROR (decimal)
ERROR (decimal)
0.3
1.2
2.4
NA
NA
NA
-
-
-
0
-
-
-
NA
NA
NA
-
-
-
-
-
-
NA
NA
NA
9.622
19.04
74.57
99.43
298.3
NA
-
-
-
-
-
-
92
46
11
8
2
-
0
255
NA
1.202
2.404
9.615
19.24
83.34
NA
NA
NA
250
0.9766
-
-
207
103
25
12
2
-
-
-
0
0.303
1.170
NA
NA
NA
NA
NA
NA
NA
+1.14
-2.48
26
6
-
-
-
-
-
-
-
+0.16
+0.16
+0.16
+0.16
-
-
-
-
-
-
-
-
-
9.6
9.6
131
65
15
12
3
-
0
255
9.615
19.231 +0.16
76.923 +0.16
1000
NA
NA
+0.16
103
51
12
9
-
-
+0.23
-0.83
-2.90
+3.57
-0.57
-
19.2
76.8
96
300
500
HIGH
LOW
19.2
79.2
97.48
316.8
NA
0
+3.13
+1.54
+5.60
-
-
-
+8.51
+4.17
-
-
-
-
-
-
-
-
-
1267
4.950
100
3.906
0
255
894.9
3.496
-
-
8.192
0.032
0
255
255
TABLE 12-4: BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 0)
FOSC = 20 MHz
%
16 MHz
10 MHz
7.15909 MHz
BAUD
RATE
(K)
SPBRG
value
SPBRG
value
SPBRG
value
SPBRG
value
%
%
%
KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal)
0.3
1.2
2.4
NA
-
-
255
129
32
15
3
2
0
-
0
NA
1.202
2.404
9.615
19.23
83.33
NA
NA
NA
250
0.977
-
-
207
103
25
12
2
-
-
-
0
NA
1.202
2.404
9.766
19.53
78.13
NA
NA
NA
156.3
0.6104
-
-
129
64
15
7
1
-
-
-
NA
1.203
2.380
9.322
18.64
NA
NA
NA
NA
111.9
0.437
-
-
92
46
11
5
-
-
-
-
1.221
2.404
9.469
19.53
78.13
104.2
312.5
NA
+1.73
+0.16
-1.36
+1.73
+1.73
+8.51
+4.17
-
+0.16
+0.16
+0.16
+0.16
+0.16
+0.16
+1.73
+1.73
+0.23
-0.83
-2.90
-2.90
-
-
-
-
-
-
9.6
19.2
76.8
96
300
500
HIGH
LOW
+8.51
+1.73
-
-
-
-
-
-
-
-
-
-
312.5
1.221
-
-
0
255
0
255
255
255
FOSC = 5.0688 MHz
4 MHz
3.579545 MHz
%
1 MHz
32.768 kHz
BAUD
RATE
(K)
SPBRG
value
SPBRG
value
SPBRG
value
SPBRG
value
SPBRG
value
%
%
%
%
KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal)
0.3
1.2
2.4
0.31
1.2
2.4
+3.13
0
0
+3.13
+3.13
+3.13
-
-
-
-
-
255
65
32
7
3
0
-
-
-
0
0.3005 -0.17
207
51
25
-
-
-
-
-
-
0.301
1.190
2.432
9.322
18.64
NA
NA
NA
NA
55.93
0.2185
+0.23
-0.83
+1.32
-2.90
185
46
22
5
2
-
-
-
-
0
0.300
1.202
2.232
NA
NA
NA
NA
NA
NA
15.63
0.0610
+0.16
+0.16
-6.99
51
12
6
-
-
-
-
-
-
0.256 -14.67
1
-
-
-
-
-
-
-
-
1.202
2.404
NA
+1.67
+1.67
NA
NA
-
-
-
-
-
-
-
-
-
-
9.6
9.9
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
NA
19.2
76.8
96
300
500
HIGH
LOW
19.8
79.2
NA
NA
NA
NA
NA
-2.90
NA
-
-
-
-
-
-
NA
NA
NA
NA
NA
NA
NA
79.2
0.3094
62.500
3.906
0
255
0
255
0.512
0.0020
0
255
255
255
DS30390E-page 102
1997 Microchip Technology Inc.
PIC16C7X
TABLE 12-5: BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 1)
FOSC = 20 MHz
%
16 MHz
10 MHz
7.16 MHz
BAUD
RATE
(K)
SPBRG
value
SPBRG
value
SPBRG
value
SPBRG
value
%
%
%
KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal)
9.6
9.615
19.230
37.878
56.818
+0.16
+0.16
-1.36
-1.36
-1.36
0
129
64
32
21
10
4
9.615
19.230
38.461
58.823
111.111
250
+0.16
+0.16
+0.16
+2.12
-3.55
0
103
51
25
16
8
9.615
18.939
39.062
56.818
125
+0.16
-1.36
+1.7
-1.36
+8.51
-
64
32
15
10
4
9.520
19.454
37.286
55.930
111.860
NA
-0.83
+1.32
-2.90
-2.90
-2.90
-
46
22
11
7
3
-
19.2
38.4
57.6
115.2 113.636
250
625
250
625
3
-
NA
625
-
0
0
1
NA
-
0
NA
-
-
1250
1250
0
0
NA
-
-
NA
-
-
NA
-
-
FOSC = 5.068 MHz
%
4 MHz
3.579 MHz
1 MHz
32.768 kHz
BAUD
RATE
(K)
SPBRG
value
SPBRG
value
SPBRG
value
SPBRG
value
SPBRG
value
%
%
%
%
KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal) KBAUD ERROR (decimal)
9.6
19.2
9.6
18.645
0
32
16
NA
1.202
-
-
9.727
18.643 -2.90
+1.32
22
11
8.928
20.833 +8.51
-6.99
6
2
NA
NA
-
-
-
-
-2.94
207
+0.17
+0.13
+0.16
38.4
57.6
115.2
250
625
1250
39.6
52.8
105.6
NA
NA
NA
+3.12
-8.33
-8.33
-
-
-
7
5
2
-
-
-
2.403
9.615
19.231 +0.16
NA
NA
NA
103
25
12
-
-
-
37.286 -2.90
55.930 -2.90
111.860 -2.90
223.721 -10.51
NA
NA
5
3
1
0
-
31.25 -18.61
1
0
-
-
-
NA
NA
NA
NA
NA
NA
-
-
-
-
-
-
-
-
-
-
-
-
62.5
NA
NA
NA
NA
+8.51
-
-
-
-
-
-
-
-
-
-
-
Note: For the PIC16C73/73A/74/74A, the asynchronous high speed mode (BRGH = 1) may experience a high
rate of receive errors. It is recommended that BRGH = 0. If you desire a higher baud rate than BRGH = 0
can support, refer to the device errata for additional information, or use the PIC16C76/77.
1997 Microchip Technology Inc.
DS30390E-page 103
PIC16C7X
12.1.1 SAMPLING
set (i.e., at the high baud rates), the sampling is done
on the 3 clock edges preceding the second rising edge
after the first falling edge of a x4 clock (Figure 12-4 and
Figure 12-5).
The data on the RC7/RX/DT pin is sampled three times
by a majority detect circuit to determine if a high or a
low level is present at the RX pin. If bit BRGH
(TXSTA<2>) is clear (i.e., at the low baud rates), the
sampling is done on the seventh, eighth and ninth fall-
ing edges of a x16 clock (Figure 12-3). If bit BRGH is
FIGURE 12-3: RX PIN SAMPLING SCHEME. BRGH = 0 (PIC16C73/73A/74/74A)
Start bit
Bit0
RX
(RC7/RX/DT pin)
Baud CLK for all but start bit
baud CLK
x16 CLK
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
1
2
3
Samples
FIGURE 12-4: RX PIN SAMPLING SCHEME, BRGH = 1 (PIC16C73/73A/74/74A)
RX pin
bit0
bit1
Start Bit
baud clk
First falling edge after RX pin goes low
Second rising edge
x4 clk
1
2
3
4
1
2
3
4
1
2
Q2, Q4 clk
Samples
Samples
Samples
FIGURE 12-5: RX PIN SAMPLING SCHEME, BRGH = 1 (PIC16C73/73A/74/74A)
RX pin
Start Bit
bit0
Baud clk for all but start bit
baud clk
First falling edge after RX pin goes low
Second rising edge
x4 clk
1
2
3
4
Q2, Q4 clk
Samples
DS30390E-page 104
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 12-6: RX PIN SAMPLING SCHEME, BRGH = 0 OR BRGH = 1 (PIC16C76/77)
Start bit
Bit0
RX
(RC7/RX/DT pin)
Baud CLK for all but start bit
baud CLK
x16 CLK
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
1
2
3
Samples
1997 Microchip Technology Inc.
DS30390E-page 105
PIC16C7X
flag bit TXIF (PIR1<4>) is set. This interrupt can be
enabled/disabled by setting/clearing enable bit TXIE
( PIE1<4>). Flag bit TXIF will be set regardless of the
state of enable bit TXIE and cannot be cleared in soft-
ware. It will reset only when new data is loaded into the
TXREG register. While flag bit TXIF indicated the sta-
tus of the TXREG register, another bit TRMT
(TXSTA<1>) shows the status of the TSR register. Sta-
tus bit TRMT is a read only bit which is set when the
TSR register is empty. No interrupt logic is tied to this
bit, so the user has to poll this bit in order to determine
if the TSR register is empty.
12.2
USART Asynchronous Mode
Applicable Devices
72 73 73A 74 74A 76 77
In this mode, the USART uses standard nonreturn-to-
zero (NRZ) format (one start bit, eight or nine data bits
and one stop bit). The most common data format is
8-bits. An on-chip dedicated 8-bit baud rate generator
can be used to derive standard baud rate frequencies
from the oscillator. The USART transmits and receives
the LSb first.The USART’s transmitter and receiver are
functionally independent but use the same data format
and baud rate. The baud rate generator produces a
clock either x16 or x64 of the bit shift rate, depending
on bit BRGH (TXSTA<2>). Parity is not supported by
the hardware, but can be implemented in software (and
stored as the ninth data bit). Asynchronous mode is
stopped during SLEEP.
Note 1: The TSR register is not mapped in data
memory so it is not available to the user.
Note 2: Flag bit TXIF is set when enable bit TXEN
is set.
Transmission is enabled by setting enable bit TXEN
(TXSTA<5>). The actual transmission will not occur
until the TXREG register has been loaded with data
and the baud rate generator (BRG) has produced a
shift clock (Figure 12-7). The transmission can also be
started by first loading the TXREG register and then
setting enable bit TXEN. Normally when transmission
is first started, the TSR register is empty, so a transfer
to the TXREG register will result in an immediate trans-
fer to TSR resulting in an empty TXREG. A back-to-
back transfer is thus possible (Figure 12-9). Clearing
enable bit TXEN during a transmission will cause the
transmission to be aborted and will reset the transmit-
ter. As a result the RC6/TX/CK pin will revert to hi-
impedance.
Asynchronous mode is selected by clearing bit SYNC
(TXSTA<4>).
The USART Asynchronous module consists of the fol-
lowing important elements:
• Baud Rate Generator
• Sampling Circuit
• Asynchronous Transmitter
• Asynchronous Receiver
12.2.1 USART ASYNCHRONOUS TRANSMITTER
The USART transmitter block diagram is shown in
Figure 12-7. The heart of the transmitter is the transmit
(serial) shift register (TSR).The shift register obtains its
data from the read/write transmit buffer, TXREG. The
TXREG register is loaded with data in software. The
TSR register is not loaded until the STOP bit has been
transmitted from the previous load. As soon as the
STOP bit is transmitted, the TSR is loaded with new
data from the TXREG register (if available). Once the
TXREG register transfers the data to the TSR register
(occurs in one TCY), the TXREG register is empty and
In order to select 9-bit transmission, transmit bit TX9
(TXSTA<6>) should be set and the ninth bit should be
written to TX9D (TXSTA<0>). The ninth bit must be
written before writing the 8-bit data to the TXREG reg-
ister. This is because a data write to the TXREG regis-
ter can result in an immediate transfer of the data to the
TSR register (if the TSR is empty). In such a case, an
incorrect ninth data bit maybe loaded in the TSR regis-
ter.
FIGURE 12-7: USART TRANSMIT BLOCK DIAGRAM
Data Bus
TXIF
TXREG register
TXIE
8
MSb
(8)
LSb
0
Pin Buffer
and Control
•
•
•
TSR register
RC6/TX/CK pin
Interrupt
TXEN
Baud Rate CLK
TRMT
SPEN
SPBRG
Baud Rate Generator
TX9
TX9D
DS30390E-page 106
1997 Microchip Technology Inc.
PIC16C7X
Steps to follow when setting up an Asynchronous
Transmission:
4. If 9-bit transmission is desired, then set transmit
bit TX9.
5. Enable the transmission by setting bit TXEN,
which will also set bit TXIF.
1. Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is desired,
set bit BRGH. (Section 12.1)
6. If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
2. Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
7. Load data to the TXREG register (starts trans-
mission).
3. If interrupts are desired, then set enable bit
TXIE.
FIGURE 12-8: ASYNCHRONOUS MASTER TRANSMISSION
Write to TXREG
Word 1
BRG output
(shift clock)
RC6/TX/CK (pin)
Start Bit
Bit 0
Bit 1
WORD 1
Bit 7/8
Stop Bit
TXIF bit
(Transmit buffer
reg. empty flag)
WORD 1
Transmit Shift Reg
TRMT bit
(Transmit shift
reg. empty flag)
FIGURE 12-9: ASYNCHRONOUS MASTER TRANSMISSION (BACK TO BACK)
Write to TXREG
Word 2
Word 1
BRG output
(shift clock)
RC6/TX/CK (pin)
Start Bit
Start Bit
WORD 2
Bit 0
Bit 1
Bit 7/8
Bit 0
Stop Bit
TXIF bit
(interrupt reg. flag)
WORD 1
TRMT bit
(Transmit shift
reg. empty flag)
WORD 1
Transmit Shift Reg.
WORD 2
Transmit Shift Reg.
Note: This timing diagram shows two consecutive transmissions.
TABLE 12-6: REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Value on:
POR,
BOR
Value on
all other
Resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(1)
0000 0000 0000 0000
0000 -00x 0000 -00x
0000 0000 0000 0000
0000 0000 0000 0000
0000 -010 0000 -010
0000 0000 0000 0000
0Ch
18h
19h
8Ch
PIR1
PSPIF
SPEN
ADIF
RX9
RCIF
TXIF SSPIF CCP1IF TMR2IF TMR1IF
FERR OERR RX9D
RCSTA
SREN CREN
—
TXREG USART Transmit Register
(1)
PIE1
PSPIE
CSRC
ADIE
TX9
RCIE
TXIE SSPIE CCP1IE TMR2IE TMR1IE
SYNC BRGH TRMT TX9D
98h
99h
TXSTA
TXEN
—
SPBRG Baud Rate Generator Register
Legend: x= unknown, -= unimplemented locations read as '0'. Shaded cells are not used for Asynchronous Transmission.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
1997 Microchip Technology Inc.
DS30390E-page 107
PIC16C7X
12.2.2 USART ASYNCHRONOUS RECEIVER
double buffered register, i.e. it is a two deep FIFO. It is
possible for two bytes of data to be received and trans-
ferred to the RCREG FIFO and a third byte begin shift-
ing to the RSR register. On the detection of the STOP
bit of the third byte, if the RCREG register is still full
then overrun error bit OERR (RCSTA<1>) will be set.
The word in the RSR will be lost. The RCREG register
can be read twice to retrieve the two bytes in the FIFO.
Overrun bit OERR has to be cleared in software. This
is done by resetting the receive logic (CREN is cleared
and then set). If bit OERR is set, transfers from the
RSR register to the RCREG register are inhibited, so it
is essential to clear error bit OERR if it is set. Framing
error bit FERR (RCSTA<2>) is set if a stop bit is
detected as clear. Bit FERR and the 9th receive bit are
buffered the same way as the receive data. Reading
the RCREG, will load bits RX9D and FERR with new
values, therefore it is essential for the user to read the
RCSTA register before reading RCREG register in
order not to lose the old FERR and RX9D information.
The receiver block diagram is shown in Figure 12-10.
The data is received on the RC7/RX/DT pin and drives
the data recovery block. The data recovery block is
actually a high speed shifter operating at x16 times the
baud rate, whereas the main receive serial shifter oper-
ates at the bit rate or at FOSC.
Once Asynchronous mode is selected, reception is
enabled by setting bit CREN (RCSTA<4>).
The heart of the receiver is the receive (serial) shift reg-
ister (RSR). After sampling the STOP bit, the received
data in the RSR is transferred to the RCREG register (if
it is empty). If the transfer is complete, flag bit RCIF
(PIR1<5>) is set. The actual interrupt can be enabled/
disabled by setting/clearing enable bit RCIE
(PIE1<5>). Flag bit RCIF is a read only bit which is
cleared by the hardware. It is cleared when the RCREG
register has been read and is empty. The RCREG is a
FIGURE 12-10: USART RECEIVE BLOCK DIAGRAM
x64 Baud Rate CLK
FERR
OERR
CREN
SPBRG
÷ 64
RSR register
LSb
MSb
or
÷ 16
0
Baud Rate Generator
1
7
Stop (8)
Start
• • •
RC7/RX/DT
Pin Buffer
and Control
Data
Recovery
RX9
RX9D
SPEN
RCREG register
FIFO
8
RCIF
RCIE
Interrupt
Data Bus
FIGURE 12-11: ASYNCHRONOUS RECEPTION
Start
bit
Start
bit
Start
bit
RX (pin)
bit0
bit1
Stop
bit
Stop
bit
bit7/8 Stop
bit
bit0
bit7/8
bit7/8
Rcv shift
reg
Rcv buffer reg
WORD 2
RCREG
WORD 1
RCREG
Read Rcv
buffer reg
RCREG
RCIF
(interrupt flag)
OERR bit
CREN
Note: This timing diagram shows three words appearing on the RX input. The RCREG (receive buffer) is read after the third word,
causing the OERR (overrun) bit to be set.
DS30390E-page 108
1997 Microchip Technology Inc.
PIC16C7X
Steps to follow when setting up an Asynchronous
Reception:
6. Flag bit RCIF will be set when reception is com-
plete and an interrupt will be generated if enable
bit RCIE was set.
1. Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is desired,
set bit BRGH. (Section 12.1).
7. Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
2. Enable the asynchronous serial port by clearing
bit SYNC, and setting bit SPEN.
8. Read the 8-bit received data by reading the
RCREG register.
3. If interrupts are desired, then set enable bit
RCIE.
9. If any error occurred, clear the error by clearing
enable bit CREN.
4. If 9-bit reception is desired, then set bit RX9.
5. Enable the reception by setting bit CREN.
TABLE 12-7: REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Value on:
POR,
BOR
Value on
all other
Resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(1)
0Ch
18h
1Ah
8Ch
98h
99h
PIR1
PSPIF
SPEN
ADIF
RX9
RCIF
TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
RCSTA
SREN CREN
—
FERR
OERR
RX9D
0000 -00x 0000 -00x
0000 0000 0000 0000
RCREG USART Receive Register
(1)
PIE1
PSPIE
CSRC
ADIE
TX9
RCIE
TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
TXSTA
TXEN SYNC
—
BRGH
TRMT
TX9D
0000 -010 0000 -010
0000 0000 0000 0000
SPBRG Baud Rate Generator Register
Legend: x= unknown, -= unimplemented locations read as '0'. Shaded cells are not used for Asynchronous Reception.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
1997 Microchip Technology Inc.
DS30390E-page 109
PIC16C7X
Clearing enable bit TXEN, during a transmission, will
cause the transmission to be aborted and will reset the
transmitter. The DT and CK pins will revert to hi-imped-
ance. If either bit CREN or bit SREN is set, during a
transmission, the transmission is aborted and the DT
pin reverts to a hi-impedance state (for a reception).
The CK pin will remain an output if bit CSRC is set
(internal clock). The transmitter logic however is not
reset although it is disconnected from the pins. In order
to reset the transmitter, the user has to clear bit TXEN.
If bit SREN is set (to interrupt an on-going transmission
and receive a single word), then after the single word is
received, bit SREN will be cleared and the serial port
will revert back to transmitting since bit TXEN is still set.
The DT line will immediately switch from hi-impedance
receive mode to transmit and start driving. To avoid
this, bit TXEN should be cleared.
12.3
USART Synchronous Master Mode
Applicable Devices
72 73 73A 74 74A 76 77
In Synchronous Master mode, the data is transmitted in
a half-duplex manner i.e. transmission and reception
do not occur at the same time. When transmitting data,
the reception is inhibited and vice versa. Synchronous
mode is entered by setting bit SYNC (TXSTA<4>). In
addition enable bit SPEN (RCSTA<7>) is set in order to
configure the RC6/TX/CK and RC7/RX/DT I/O pins to
CK (clock) and DT (data) lines respectively.The Master
mode indicates that the processor transmits the master
clock on the CK line. The Master mode is entered by
setting bit CSRC (TXSTA<7>).
12.3.1 USART SYNCHRONOUS MASTER
TRANSMISSION
In order to select 9-bit transmission, the TX9
(TXSTA<6>) bit should be set and the ninth bit should
be written to bit TX9D (TXSTA<0>). The ninth bit must
be written before writing the 8-bit data to the TXREG
register.This is because a data write to the TXREG can
result in an immediate transfer of the data to the TSR
register (if the TSR is empty). If the TSR was empty and
the TXREG was written before writing the “new” TX9D,
the “present” value of bit TX9D is loaded.
The USART transmitter block diagram is shown in
Figure 12-7. The heart of the transmitter is the transmit
(serial) shift register (TSR).The shift register obtains its
data from the read/write transmit buffer register
TXREG. The TXREG register is loaded with data in
software. The TSR register is not loaded until the last
bit has been transmitted from the previous load. As
soon as the last bit is transmitted, the TSR is loaded
with new data from the TXREG (if available). Once the
TXREG register transfers the data to the TSR register
(occurs in one Tcycle), the TXREG is empty and inter-
rupt bit, TXIF (PIR1<4>) is set. The interrupt can be
enabled/disabled by setting/clearing enable bit TXIE
(PIE1<4>). Flag bit TXIF will be set regardless of the
state of enable bit TXIE and cannot be cleared in soft-
ware. It will reset only when new data is loaded into the
TXREG register.While flag bit TXIF indicates the status
of the TXREG register, another bit TRMT (TXSTA<1>)
shows the status of the TSR register. TRMT is a read
only bit which is set when the TSR is empty. No inter-
rupt logic is tied to this bit, so the user has to poll this
bit in order to determine if the TSR register is empty.
The TSR is not mapped in data memory so it is not
available to the user.
Steps to follow when setting up a Synchronous Master
Transmission:
1. Initialize the SPBRG register for the appropriate
baud rate (Section 12.1).
2. Enable the synchronous master serial port by
setting bits SYNC, SPEN, and CSRC.
3. If interrupts are desired, then set enable bit
TXIE.
4. If 9-bit transmission is desired, then set bit TX9.
5. Enable the transmission by setting bit TXEN.
6. If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
7. Start transmission by loading data to the
TXREG register.
Transmission is enabled by setting enable bit TXEN
(TXSTA<5>). The actual transmission will not occur
until the TXREG register has been loaded with data.
The first data bit will be shifted out on the next available
rising edge of the clock on the CK line. Data out is sta-
ble around the falling edge of the synchronous clock
(Figure 12-12).The transmission can also be started by
first loading the TXREG register and then setting bit
TXEN (Figure 12-13). This is advantageous when slow
baud rates are selected, since the BRG is kept in reset
when bits TXEN, CREN, and SREN are clear. Setting
enable bit TXEN will start the BRG, creating a shift
clock immediately. Normally when transmission is first
started, the TSR register is empty, so a transfer to the
TXREG register will result in an immediate transfer to
TSR resulting in an empty TXREG. Back-to-back trans-
fers are possible.
DS30390E-page 110
1997 Microchip Technology Inc.
PIC16C7X
TABLE 12-8:
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTERTRANSMISSION
Value on:
POR,
BOR
Value on all
other Resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(1)
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0Ch
18h
19h
8Ch
98h
99h
PIR1
PSPIF
SPEN
ADIF
RX9
RCIF
TXIF SSPIF CCP1IF TMR2IF TMR1IF
FERR OERR RX9D
RCSTA
SREN CREN
—
TXREG USART Transmit Register
(1)
PIE1
PSPIE
CSRC
ADIE
TX9
RCIE
TXIE SSPIE CCP1IE TMR2IE TMR1IE
BRGH TRMT TX9D
TXSTA
TXEN SYNC
—
SPBRG Baud Rate Generator Register
Legend: x= unknown, -= unimplemented, read as '0'. Shaded cells are not used for Synchronous Master Transmission.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
FIGURE 12-12: SYNCHRONOUS TRANSMISSION
Q1Q2 Q3Q4 Q1 Q2Q3 Q4Q1 Q2Q3 Q4Q1 Q2Q3 Q4Q1 Q2 Q3Q4
Q3Q4 Q1Q2 Q3Q4 Q1Q2 Q3Q4 Q1Q2 Q3 Q4Q1 Q2Q3 Q4Q1 Q2Q3 Q4Q1 Q2Q3 Q4
RC7/RX/DT pin
RC6/TX/CK pin
Bit 0
Bit 1
Bit 2
Bit 7
Bit 0
Bit 1
WORD 2
Bit 7
WORD 1
Write to
TXREG reg
Write word1
Write word2
TXIF bit
(Interrupt flag)
TRMT bit
'1'
Note: Sync master mode; SPBRG = '0'. Continuous transmission of two 8-bit words
'1'
TXEN bit
FIGURE 12-13: SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
RC7/RX/DT pin
RC6/TX/CK pin
bit0
bit2
bit1
bit6
bit7
Write to
TXREG reg
TXIF bit
TRMT bit
TXEN bit
1997 Microchip Technology Inc.
DS30390E-page 111
PIC16C7X
12.3.2 USART SYNCHRONOUS MASTER
RECEPTION
Steps to follow when setting up a Synchronous Master
Reception:
1. Initialize the SPBRG register for the appropriate
baud rate. (Section 12.1)
Once Synchronous mode is selected, reception is
enabled by setting either enable bit SREN
(RCSTA<5>) or enable bit CREN (RCSTA<4>). Data is
sampled on the RC7/RX/DT pin on the falling edge of
the clock. If enable bit SREN is set, then only a single
word is received. If enable bit CREN is set, the recep-
tion is continuous until CREN is cleared. If both bits are
set then CREN takes precedence. After clocking the
last bit, the received data in the Receive Shift Register
(RSR) is transferred to the RCREG register (if it is
empty). When the transfer is complete, interrupt flag bit
RCIF (PIR1<5>) is set. The actual interrupt can be
enabled/disabled by setting/clearing enable bit RCIE
(PIE1<5>). Flag bit RCIF is a read only bit which is
reset by the hardware. In this case it is reset when the
RCREG register has been read and is empty. The
RCREG is a double buffered register, i.e. it is a two
deep FIFO. It is possible for two bytes of data to be
received and transferred to the RCREG FIFO and a
third byte to begin shifting into the RSR register. On the
clocking of the last bit of the third byte, if the RCREG
register is still full then overrun error bit OERR
(RCSTA<1>) is set. The word in the RSR will be lost.
The RCREG register can be read twice to retrieve the
two bytes in the FIFO. Bit OERR has to be cleared in
software (by clearing bit CREN). If bit OERR is set,
transfers from the RSR to the RCREG are inhibited, so
it is essential to clear bit OERR if it is set. The 9th
receive bit is buffered the same way as the receive
data. Reading the RCREG register, will load bit RX9D
with a new value, therefore it is essential for the user to
read the RCSTA register before reading RCREG in
order not to lose the old RX9D information.
2. Enable the synchronous master serial port by
setting bits SYNC, SPEN, and CSRC.
3. Ensure bits CREN and SREN are clear.
4. If interrupts are desired, then set enable bit
RCIE.
5. If 9-bit reception is desired, then set bit RX9.
6. If a single reception is required, set bit SREN.
For continuous reception set bit CREN.
7. Interrupt flag bit RCIF will be set when reception
is complete and an interrupt will be generated if
enable bit RCIE was set.
8. Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
9. Read the 8-bit received data by reading the
RCREG register.
10. If any error occurred, clear the error by clearing
bit CREN.
TABLE 12-9: REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
Value on:
POR,
BOR
Value on all
other Resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(1)
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0Ch
18h
1Ah
8Ch
98h
99h
PIR1
PSPIF
SPEN
ADIF
RCIF
TXIF SSPIF CCP1IF TMR2IF TMR1IF
FERR OERR RX9D
RCSTA
RX9 SREN CREN
—
RCREG USART Receive Register
(1)
PIE1
PSPIE
CSRC
ADIE RCIE
TXIE SSPIE CCP1IE TMR2IE TMR1IE
BRGH TRMT TX9D
TXSTA
TX9 TXEN SYNC
—
SPBRG Baud Rate Generator Register
Legend: x= unknown, -= unimplemented read as '0'. Shaded cells are not used for Synchronous Master Reception.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
DS30390E-page 112
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 12-14: SYNCHRONOUS RECEPTION (MASTER MODE, SREN)
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
RC7/RX/DT pin
RC6/TX/CK pin
bit0
bit1
bit2
bit3
bit4
bit5
bit6
bit7
Write to
bit SREN
SREN bit
CREN bit
'0'
'0'
RCIF bit
(interrupt)
Read
RXREG
Note: Timing diagram demonstrates SYNC master mode with bit SREN = '1' and bit BRG = '0'.
1997 Microchip Technology Inc.
DS30390E-page 113
PIC16C7X
12.4.2 USART SYNCHRONOUS SLAVE
RECEPTION
12.4
USART Synchronous Slave Mode
Applicable Devices
72 73 73A 74 74A 76 77
The operation of the synchronous master and slave
modes is identical except in the case of the SLEEP
mode. Also, bit SREN is a don't care in slave mode.
Synchronous slave mode differs from the Master mode
in the fact that the shift clock is supplied externally at
the RC6/TX/CK pin (instead of being supplied internally
in master mode). This allows the device to transfer or
receive data while in SLEEP mode. Slave mode is
entered by clearing bit CSRC (TXSTA<7>).
If receive is enabled, by setting bit CREN, prior to the
SLEEPinstruction, then a word may be received during
SLEEP. On completely receiving the word, the RSR
register will transfer the data to the RCREG register
and if enable bit RCIE bit is set, the interrupt generated
will wake the chip from SLEEP. If the global interrupt is
enabled, the program will branch to the interrupt vector
(0004h).
12.4.1 USART SYNCHRONOUS SLAVE
TRANSMIT
The operation of the synchronous master and slave
modes are identical except in the case of the SLEEP
mode.
Steps to follow when setting up a Synchronous Slave
Reception:
If two words are written to the TXREG and then the
SLEEPinstruction is executed, the following will occur:
1. Enable the synchronous master serial port by
setting bits SYNC and SPEN and clearing bit
CSRC.
a) The first word will immediately transfer to the
TSR register and transmit.
2. If interrupts are desired, then set enable bit
RCIE.
b) The second word will remain in TXREG register.
c) Flag bit TXIF will not be set.
3. If 9-bit reception is desired, then set bit RX9.
4. To enable reception, set enable bit CREN.
d) When the first word has been shifted out of TSR,
the TXREG register will transfer the second
word to the TSR and flag bit TXIF will now be
set.
5. Flag bit RCIF will be set when reception is com-
plete and an interrupt will be generated, if
enable bit RCIE was set.
e) If enable bit TXIE is set, the interrupt will wake
the chip from SLEEP and if the global interrupt
is enabled, the program will branch to the inter-
rupt vector (0004h).
6. Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
7. Read the 8-bit received data by reading the
RCREG register.
Steps to follow when setting up a Synchronous Slave
Transmission:
8. If any error occurred, clear the error by clearing
bit CREN.
1. Enable the synchronous slave serial port by set-
ting bits SYNC and SPEN and clearing bit
CSRC.
2. Clear bits CREN and SREN.
3. If interrupts are desired, then set enable bit
TXIE.
4. If 9-bit transmission is desired, then set bit TX9.
5. Enable the transmission by setting enable bit
TXEN.
6. If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
7. Start transmission by loading data to the
TXREG register.
DS30390E-page 114
1997 Microchip Technology Inc.
PIC16C7X
TABLE 12-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION
Value on:
POR,
BOR
Value on all
other Resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(1)
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0Ch
18h
19h
8Ch
98h
99h
PIR1
PSPIF
SPEN
ADIF
RX9
RCIF
TXIF SSPIF CCP1IF TMR2IF TMR1IF
FERR OERR RX9D
RCSTA
SREN CREN
—
TXREG USART Transmit Register
(1)
PIE1
PSPIE
CSRC
ADIE
TX9
RCIE
TXIE SSPIE CCP1IE TMR2IE TMR1IE
BRGH TRMT TX9D
TXSTA
TXEN SYNC
—
SPBRG Baud Rate Generator Register
Legend: x= unknown, -= unimplemented read as '0'. Shaded cells are not used for Synchronous Slave Transmission.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
TABLE 12-11: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION
Value on:
POR,
BOR
Value on all
other Resets
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(1)
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
0Ch
18h
1Ah
8Ch
98h
99h
PIR1
PSPIF
SPEN
ADIF
RCIF
TXIF SSPIF CCP1IF TMR2IF TMR1IF
FERR OERR RX9D
RCSTA
RX9 SREN CREN
—
RCREG USART Receive Register
(1)
PIE1
PSPIE
CSRC
ADIE RCIE
TXIE SSPIE CCP1IE TMR2IE TMR1IE
BRGH TRMT TX9D
TXSTA
TX9 TXEN SYNC
—
SPBRG Baud Rate Generator Register
Legend: x= unknown, -= unimplemented read as '0'. Shaded cells are not used for Synchronous Slave Reception.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
1997 Microchip Technology Inc.
DS30390E-page 115
PIC16C7X
NOTES:
DS30390E-page 116
1997 Microchip Technology Inc.
PIC16C7X
The A/D converter has a unique feature of being able to
operate while the device is in SLEEP mode. To operate
in sleep, the A/D conversion clock must be derived from
the A/D’s internal RC oscillator.
13.0 ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
Applicable Devices
72 73 73A 74 74A 76 77
The A/D module has three registers. These registers
are:
The analog-to-digital (A/D) converter module has five
inputs for the PIC16C72/73/73A/76, and eight for the
PIC16C74/74A/77.
• A/D Result Register (ADRES)
• A/D Control Register 0 (ADCON0)
• A/D Control Register 1 (ADCON1)
The A/D allows conversion of an analog input signal to
a corresponding 8-bit digital number (refer to Applica-
tion Note AN546 for use of A/D Converter). The output
of the sample and hold is the input into the converter,
which generates the result via successive approxima-
tion. The analog reference voltage is software select-
able to either the device’s positive supply voltage (VDD)
or the voltage level on the RA3/AN3/VREF pin.
The ADCON0 register, shown in Figure 13-1, controls
the operation of the A/D module. The ADCON1 regis-
ter, shown in Figure 13-2, configures the functions of
the port pins. The port pins can be configured as ana-
log inputs (RA3 can also be a voltage reference) or as
digital I/O.
FIGURE 13-1: ADCON0 REGISTER (ADDRESS 1Fh)
R/W-0 R/W-0
R/W-0
R/W-0
CHS1
R/W-0
CHS0
R/W-0
U-0
—
R/W-0
ADON
ADCS1 ADCS0 CHS2
bit7
GO/DONE
R =Readable bit
W = Writable bit
U =Unimplemented bit,
read as ‘0’
bit0
- n = Value at POR reset
bit 7-6: ADCS1:ADCS0: A/D Conversion Clock Select bits
00= FOSC/2
01= FOSC/8
10= FOSC/32
11= FRC (clock derived from an internal RC oscillator)
bit 5-3: CHS2:CHS0: Analog Channel Select bits
000= channel 0, (RA0/AN0)
001= channel 1, (RA1/AN1)
010= channel 2, (RA2/AN2)
011= channel 3, (RA3/AN3)
100= channel 4, (RA5/AN4)
(1)
101= channel 5, (RE0/AN5)
(1)
110= channel 6, (RE1/AN6)
(1)
111= channel 7, (RE2/AN7)
bit 2:
GO/DONE: A/D Conversion Status bit
If ADON = 1
1 = A/D conversion in progress (setting this bit starts the A/D conversion)
0 = A/D conversion not in progress (This bit is automatically cleared by hardware when the A/D conversion
is complete)
bit 1:
bit 0:
Unimplemented: Read as '0'
ADON: A/D On bit
1 = A/D converter module is operating
0 = A/D converter module is shutoff and consumes no operating current
Note 1: A/D channels 5, 6, and 7 are implemented on the PIC16C74/74A/77 only.
1997 Microchip Technology Inc.
DS30390E-page 117
PIC16C7X
FIGURE 13-2: ADCON1 REGISTER (ADDRESS 9Fh)
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
R/W-0
R/W-0
R/W-0
PCFG2
PCFG1
PCFG0
R =Readable bit
W = Writable bit
bit7
bit0
U =Unimplemented
bit, read as ‘0’
- n = Value at POR reset
bit 7-3: Unimplemented: Read as '0'
bit 2-0: PCFG2:PCFG0: A/D Port Configuration Control bits
(1)
(1)
(1)
PCFG2:PCFG0
RA0
RA1
RA2
RA5
RA3
VREF
VDD
RE0
RE1
RE2
000
001
010
011
100
101
11x
A
A
A
A
A
A
A
D
D
D
D
D
A
A
D
D
D
D
D
A
A
D
D
D
D
D
A
A
A
A
A
D
A
A
A
A
A
D
A
A
A
D
D
D
A
A
A
D
D
D
VREF
A
RA3
VDD
RA3
VDD
RA3
—
VREF
A
VREF
D
A = Analog input
D = Digital I/O
Note 1: RE0, RE1, and RE2 are implemented on the PIC16C74/74A/77 only.
DS30390E-page 118
1997 Microchip Technology Inc.
PIC16C7X
The ADRES register contains the result of the A/D con-
version. When the A/D conversion is complete, the
result is loaded into the ADRES register, the GO/DONE
bit (ADCON0<2>) is cleared, and A/D interrupt flag bit
ADIF is set. The block diagrams of the A/D module are
shown in Figure 13-3.
3. Wait the required acquisition time.
4. Start conversion:
• Set GO/DONE bit (ADCON0)
5. Wait for A/D conversion to complete, by either:
• Polling for the GO/DONE bit to be cleared
OR
After the A/D module has been configured as desired,
the selected channel must be acquired before the con-
version is started. The analog input channels must
have their corresponding TRIS bits selected as an
input. To determine acquisition time, see Section 13.1.
After this acquisition time has elapsed the A/D conver-
sion can be started. The following steps should be fol-
lowed for doing an A/D conversion:
• Waiting for the A/D interrupt
6. Read A/D Result register (ADRES), clear bit
ADIF if required.
7. For next conversion, go to step 1 or step 2 as
required. The A/D conversion time per bit is
defined as TAD. A minimum wait of 2TAD is
required before next acquisition starts.
1. Configure the A/D module:
• Configure analog pins / voltage reference /
and digital I/O (ADCON1)
• Select A/D input channel (ADCON0)
• Select A/D conversion clock (ADCON0)
• Turn on A/D module (ADCON0)
2. Configure A/D interrupt (if desired):
• Clear ADIF bit
• Set ADIE bit
• Set GIE bit
FIGURE 13-3: A/D BLOCK DIAGRAM
CHS2:CHS0
111
(1)
RE2/AN7
110
(1)
RE1/AN6
101
(1)
RE0/AN5
100
RA5/AN4
VIN
011
(Input voltage)
RA3/AN3/VREF
010
RA2/AN2
A/D
Converter
001
RA1/AN1
000
VDD
RA0/AN0
000or
010or
100
VREF
(Reference
voltage)
001or
011or
101
PCFG2:PCFG0
Note 1: Not available on PIC16C72/73/73A/76.
1997 Microchip Technology Inc.
DS30390E-page 119
PIC16C7X
VDD = 5V → Rss = 7 kΩ
13.1
A/D Acquisition Requirements
Applicable Devices
Temp (application system max.) = 50°C
VHOLD = 0 @ t = 0
72 73 73A 74 74A 76 77
For the A/D converter to meet its specified accuracy,
the charge holding capacitor (CHOLD) must be allowed
to fully charge to the input channel voltage level. The
analog input model is shown in Figure 13-4.The source
impedance (RS) and the internal sampling switch (RSS)
impedance directly affect the time required to charge
the capacitor CHOLD.The sampling switch (RSS) imped-
ance varies over the device voltage (VDD), Figure 13-4.
The source impedance affects the offset voltage at the
analog input (due to pin leakage current). The maxi-
mum recommended impedance for analog sources
is 10 kΩ. After the analog input channel is selected
(changed) this acquisition must be done before the con-
version can be started.
Note 1: The reference voltage (VREF) has no
effect on the equation, since it cancels
itself out.
Note 2: The charge holding capacitor (CHOLD) is
not discharged after each conversion.
Note 3: The maximum recommended impedance
for analog sources is 10 kΩ. This is
required to meet the pin leakage specifi-
cation.
Note 4: After a conversion has completed, a
2.0TAD delay must complete before acqui-
sition can begin again. During this time
the holding capacitor is not connected to
the selected A/D input channel.
To calculate the minimum acquisition time,
Equation 13-1 may be used. This equation calculates
the acquisition time to within 1/2 LSb error is used (512
steps for the A/D). The 1/2 LSb error is the maximum
error allowed for the A/D to meet its specified accuracy.
EXAMPLE 13-1: CALCULATING THE
MINIMUM REQUIRED
ACQUISITION TIME
EQUATION 13-1: A/D MINIMUM CHARGING
TACQ = Amplifier Settling Time +
Holding Capacitor Charging Time +
Temperature Coefficient
TIME
(-TCAP/CHOLD(RIC + RSS + RS))
VHOLD = (VREF - (VREF/512)) • (1 - e
)
Given: VHOLD = (VREF/512), for 1/2 LSb resolution
The above equation reduces to:
TACQ = 5 µs + TCAP + [(Temp - 25°C)(0.05 µs/°C)]
TCAP = -CHOLD (RIC + RSS + RS) ln(1/511)
-51.2 pF (1 kΩ + 7 kΩ + 10 kΩ) ln(0.0020)
-51.2 pF (18 kΩ) ln(0.0020)
TCAP = -(51.2 pF)(1 kΩ + RSS + RS) ln(1/511)
Example 13-1 shows the calculation of the minimum
required acquisition time TACQ. This calculation is
based on the following system assumptions.
-0.921 µs (-6.2364)
5.747 µs
CHOLD = 51.2 pF
Rs = 10 kΩ
TACQ = 5 µs + 5.747 µs + [(50°C - 25°C)(0.05 µs/°C)]
10.747 µs + 1.25 µs
1/2 LSb error
11.997 µs
FIGURE 13-4: ANALOG INPUT MODEL
VDD
Sampling
Switch
VT = 0.6V
ANx
SS
RIC ≤ 1k
RSS
Rs
CHOLD
= DAC capacitance
= 51.2 pF
CPIN
5 pF
VA
I leakage
± 500 nA
VT = 0.6V
VSS
Legend CPIN
VT
= input capacitance
= threshold voltage
6V
5V
I leakage = leakage current at the pin due to
various junctions
VDD 4V
3V
2V
RIC
SS
= interconnect resistance
= sampling switch
CHOLD
= sample/hold capacitance (from DAC)
5 6 7 8 9 10 11
Sampling Switch
( kΩ )
DS30390E-page 120
1997 Microchip Technology Inc.
PIC16C7X
13.2
Selecting the A/D Conversion Clock
Applicable Devices
13.3
Configuring Analog Port Pins
Applicable Devices
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
The A/D conversion time per bit is defined as TAD. The
A/D conversion requires 9.5TAD per 8-bit conversion.
The source of the A/D conversion clock is software
selectable. The four possible options for TAD are:
The ADCON1, TRISA, and TRISE registers control the
operation of the A/D port pins. The port pins that are
desired as analog inputs must have their correspond-
ing TRIS bits set (input). If the TRIS bit is cleared (out-
put), the digital output level (VOH or VOL) will be
converted.
• 2TOSC
• 8TOSC
The A/D operation is independent of the state of the
CHS2:CHS0 bits and the TRIS bits.
• 32TOSC
• Internal RC oscillator
Note 1: When reading the port register, all pins
configured as analog input channels will
read as cleared (a low level). Pins config-
ured as digital inputs, will convert an ana-
log input. Analog levels on a digitally
configured input will not affect the conver-
sion accuracy.
For correct A/D conversions, the A/D conversion clock
(TAD) must be selected to ensure a minimum TAD time
of 1.6 µs.
Table 13-1 shows the resultant TAD times derived from
the device operating frequencies and the A/D clock
source selected.
Note 2: Analog levels on any pin that is defined as
a digital input (including the AN7:AN0
pins), may cause the input buffer to con-
sume current that is out of the devices
specification.
TABLE 13-1: TAD vs. DEVICE OPERATING FREQUENCIES
Device Frequency
AD Clock Source (TAD)
Operation ADCS1:ADCS0
20 MHz
5 MHz
1.25 MHz
1.6 µs
333.33 kHz
(2)
(2)
2TOSC
8TOSC
32TOSC
00
01
10
11
6 µs
100 ns
400 ns
(2)
(3)
1.6 µs
6.4 µs
400 ns
24 µs
(3)
(3)
1.6 µs
6.4 µs
25.6 µs
96 µs
(5)
(1,4)
(1,4)
(1,4)
(1)
RC
2 - 6 µs
2 - 6 µs
2 - 6 µs
2 - 6 µs
Legend: Shaded cells are outside of recommended range.
Note 1: The RC source has a typical TAD time of 4 µs.
2: These values violate the minimum required TAD time.
3: For faster conversion times, the selection of another clock source is recommended.
4: When device frequency is greater than 1 MHz, the RC A/D conversion clock source is recommended for
sleep operation only.
5: For extended voltage devices (LC), please refer to Electrical Specifications section.
1997 Microchip Technology Inc.
DS30390E-page 121
PIC16C7X
13.4
A/D Conversions
Applicable Devices
72 73 73A 74 74A 76 77
Note: The GO/DONE bit should NOT be set in
the same instruction that turns on the A/D.
Example 13-2 shows how to perform an A/D conver-
sion. The RA pins are configured as analog inputs. The
analog reference (VREF) is the device VDD. The A/D
interrupt is enabled, and the A/D conversion clock is
FRC. The conversion is performed on the RA0 pin
(channel 0).
Clearing the GO/DONE bit during a conversion will
abort the current conversion. The ADRES register will
NOT be updated with the partially completed A/D con-
version sample. That is, the ADRES register will con-
tinue to contain the value of the last completed
conversion (or the last value written to the ADRES reg-
ister). After the A/D conversion is aborted, a 2TAD wait
is required before the next acquisition is started. After
this 2TAD wait, an acquisition is automatically started on
the selected channel.
EXAMPLE 13-2: A/D CONVERSION
BSF
BCF
CLRF
BSF
BCF
MOVLW
MOVWF
BCF
BSF
BSF
STATUS, RP0
STATUS, RP1
ADCON1
; Select Bank 1
; PIC16C76/77 only
; Configure A/D inputs
; Enable A/D interrupts
; Select Bank 0
; RC Clock, A/D is on, Channel 0 is selected
;
; Clear A/D interrupt flag bit
; Enable peripheral interrupts
; Enable all interrupts
PIE1,
ADIE
STATUS, RP0
0xC1
ADCON0
PIR1,
ADIF
INTCON, PEIE
INTCON, GIE
;
;
;
;
Ensure that the required sampling time for the selected input channel has elapsed.
Then the conversion may be started.
BSF
:
ADCON0, GO
; Start A/D Conversion
; The ADIF bit will be set and the GO/DONE bit
:
;
is cleared upon completion of the A/D Conversion.
DS30390E-page 122
1997 Microchip Technology Inc.
PIC16C7X
13.4.1 FASTER CONVERSION - LOWER
RESOLUTION TRADE-OFF
Since the TAD is based from the device oscillator, the
user must use some method (a timer, software loop,
etc.) to determine when the A/D oscillator may be
changed. Example 13-3 shows a comparison of time
required for a conversion with 4-bits of resolution, ver-
sus the 8-bit resolution conversion. The example is for
devices operating at 20 MHz and 16 MHz (The A/D
clock is programmed for 32TOSC), and assumes that
immediately after 6TAD, the A/D clock is programmed
for 2TOSC.
Not all applications require a result with 8-bits of reso-
lution, but may instead require a faster conversion time.
The A/D module allows users to make the trade-off of
conversion speed to resolution. Regardless of the res-
olution required, the acquisition time is the same. To
speed up the conversion, the clock source of the A/D
module may be switched so that the TAD time violates
the minimum specified time (see the applicable electri-
cal specification). Once the TAD time violates the mini-
mum specified time, all the following A/D result bits are
not valid (see A/D Conversion Timing in the Electrical
Specifications section.) The clock sources may only be
switched between the three oscillator versions (cannot
be switched from/to RC). The equation to determine
the time before the oscillator can be switched is as fol-
lows:
The 2TOSC violates the minimum TAD time since the last
4-bits will not be converted to correct values.
Conversion time = 2TAD + N • TAD + (8 - N)(2TOSC)
Where: N = number of bits of resolution required.
EXAMPLE 13-3: 4-BIT vs. 8-BIT CONVERSION TIMES
Resolution
(1)
Freq. (MHz)
4-bit
8-bit
TAD
20
16
20
16
20
16
1.6 µs
2.0 µs
50 ns
1.6 µs
2.0 µs
50 ns
TOSC
62.5 ns
10 µs
62.5 ns
16 µs
2TAD + N • TAD + (8 - N)(2TOSC)
12.5 µs
20 µs
Note 1: PIC16C7X devices have a minimum TAD time of 1.6 µs.
1997 Microchip Technology Inc.
DS30390E-page 123
PIC16C7X
Gain error measures the maximum deviation of the last
actual transition and the last ideal transition adjusted
for offset error.This error appears as a change in slope
of the transfer function. The difference in gain error to
full scale error is that full scale does not take offset error
into account. Gain error can be calibrated out in soft-
ware.
13.5
A/D Operation During Sleep
Applicable Devices
72 73 73A 74 74A 76 77
The A/D module can operate during SLEEP mode.This
requires that the A/D clock source be set to RC
(ADCS1:ADCS0 = 11). When the RC clock source is
selected, the A/D module waits one instruction cycle
before starting the conversion. This allows the SLEEP
instruction to be executed, which eliminates all digital
switching noise from the conversion. When the conver-
sion is completed the GO/DONEbit will be cleared, and
the result loaded into the ADRES register. If the A/D
interrupt is enabled, the device will wake-up from
SLEEP. If the A/D interrupt is not enabled, the A/D mod-
ule will then be turned off, although the ADON bit will
remain set.
Linearity error refers to the uniformity of the code
changes. Linearity errors cannot be calibrated out of
the system. Integral non-linearity error measures the
actual code transition versus the ideal code transition
adjusted by the gain error for each code.
Differential non-linearity measures the maximum actual
code width versus the ideal code width. This measure
is unadjusted.
The maximum pin leakage current is ± 1 µA.
When the A/D clock source is another clock option (not
RC), a SLEEPinstruction will cause the present conver-
sion to be aborted and the A/D module to be turned off,
though the ADON bit will remain set.
In systems where the device frequency is low, use of
the A/D RC clock is preferred. At moderate to high fre-
quencies, TAD should be derived from the device oscil-
lator. TAD must not violate the minimum and should be
≤ 8 µs for preferred operation. This is because TAD,
when derived from TOSC, is kept away from on-chip
phase clock transitions. This reduces, to a large extent,
the effects of digital switching noise. This is not possi-
ble with the RC derived clock.The loss of accuracy due
to digital switching noise can be significant if many I/O
pins are active.
Turning off the A/D places the A/D module in its lowest
current consumption state.
Note: For the A/D module to operate in SLEEP,
the A/D clock source must be set to RC
(ADCS1:ADCS0 = 11). To perform an A/D
conversion in SLEEP, ensure the SLEEP
instruction immediately follows the instruc-
tion that sets the GO/DONE bit.
In systems where the device will enter SLEEP mode
after the start of the A/D conversion, the RC clock
source selection is required. In this mode, the digital
noise from the modules in SLEEP are stopped. This
method gives high accuracy.
13.6
A/D Accuracy/Error
Applicable Devices
72 73 73A 74 74A 76 77
13.7
Effects of a RESET
Applicable Devices
72 73 73A 74 74A 76 77
The absolute accuracy specified for the A/D converter
includes the sum of all contributions for quantization
error, integral error, differential error, full scale error, off-
set error, and monotonicity. It is defined as the maxi-
mum deviation from an actual transition versus an ideal
transition for any code. The absolute error of the A/D
converter is specified at < ±1 LSb for VDD = VREF (over
the device’s specified operating range). However, the
accuracy of the A/D converter will degrade as VDD
diverges from VREF.
A device reset forces all registers to their reset state.
This forces the A/D module to be turned off, and any
conversion is aborted.
The value that is in the ADRES register is not modified
for a Power-on Reset. The ADRES register will contain
unknown data after a Power-on Reset.
For a given range of analog inputs, the output digital
code will be the same.This is due to the quantization of
the analog input to a digital code. Quantization error is
typically ± 1/2 LSb and is inherent in the analog to dig-
ital conversion process. The only way to reduce quan-
tization error is to increase the resolution of the A/D
converter.
Offset error measures the first actual transition of a
code versus the first ideal transition of a code. Offset
error shifts the entire transfer function. Offset error can
be calibrated out of a system or introduced into a sys-
tem through the interaction of the total leakage current
and source impedance at the analog input.
DS30390E-page 124
1997 Microchip Technology Inc.
PIC16C7X
13.8
Use of the CCP Trigger
Applicable Devices
FIGURE 13-5: A/D TRANSFER FUNCTION
72 73 73A 74 74A 76 77
FFh
FEh
Note: In the PIC16C72, the "special event trig-
ger" is implemented in the CCP1 module.
An A/D conversion can be started by the “special event
trigger” of the CCP2 module (CCP1 on the PIC16C72
only). This requires that the CCP2M3:CCP2M0 bits
(CCP2CON<3:0>) be programmed as 1011 and that
the A/D module is enabled (ADON bit is set). When the
trigger occurs, the GO/DONE bit will be set, starting the
A/D conversion, and the Timer1 counter will be reset to
zero. Timer1 is reset to automatically repeat the A/D
acquisition period with minimal software overhead
(moving the ADRES to the desired location). The
appropriate analog input channel must be selected and
the minimum acquisition done before the “special event
trigger” sets the GO/DONE bit (starts a conversion).
04h
03h
02h
01h
00h
Analog input voltage
If the A/D module is not enabled (ADON is cleared),
then the “special event trigger” will be ignored by the
A/D module, but will still reset the Timer1 counter.
13.11 References
13.9
Connection Considerations
Applicable Devices
A very good reference for understanding A/D convert-
ers is the "Analog-Digital Conversion Handbook" third
edition, published by Prentice Hall (ISBN
0-13-03-2848-0).
72 73 73A 74 74A 76 77
If the input voltage exceeds the rail values (VSS or VDD)
by greater than 0.2V, then the accuracy of the conver-
sion is out of specification.
An external RC filter is sometimes added for anti-alias-
ing of the input signal. The R component should be
selected to ensure that the total source impedance is
kept under the 10 kΩ recommended specification. Any
external components connected (via hi-impedance) to
an analog input pin (capacitor, zener diode, etc.) should
have very little leakage current at the pin.
13.10 Transfer Function
Applicable Devices
72 73 73A 74 74A 76 77
The ideal transfer function of the A/D converter is as
follows: the first transition occurs when the analog input
voltage (VAIN) is Analog VREF/256 (Figure 13-5).
1997 Microchip Technology Inc.
DS30390E-page 125
PIC16C7X
FIGURE 13-6: FLOWCHART OF A/D OPERATION
ADON = 0
Yes
ADON = 0?
No
Acquire
Selected Channel
Yes
GO = 0?
No
Yes
Yes
Start of A/D
Conversion Delayed
1 Instruction Cycle
Finish Conversion
SLEEP
Instruction?
A/D Clock
= RC?
GO = 0
ADIF = 1
No
No
Yes
Yes
Abort Conversion
GO = 0
Wake-up
From Sleep?
Finish Conversion
Device in
SLEEP?
Wait 2 TAD
GO = 0
ADIF = 1
ADIF = 0
No
No
SLEEP
Power-down A/D
Finish Conversion
Stay in Sleep
Power-down A/D
Wait 2 TAD
GO = 0
ADIF = 1
Wait 2 TAD
TABLE 13-2: REGISTERS/BITS ASSOCIATED WITH A/D, PIC16C72
Value on:
POR,
BOR
Value on all
other Resets
Address
Name
Bit 7
Bit 6
Bit 5 Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
INTCON
PIR1
GIE
—
PEIE
ADIF
ADIE
T0IE INTE RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
0Bh,8Bh
0Ch
8Ch
1Eh
—
—
—
—
SSPIF CCP1IF
TMR2IF TMR1IF -0-- 0000 -0-- 0000
PIE1
—
SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000
ADRES
A/D Result Register
xxxx xxxx uuuu uuuu
ADCON0 ADCS1 ADCS0 CHS2 CHS1 CHS0 GO/DONE
—
ADON 0000 00-0 0000 00-0
1Fh
ADCON1
—
—
—
—
—
PCFG2
RA2
PCFG1 PCFG0 ---- -000 ---- -000
9Fh
--0x 0000 --0u 0000
--11 1111 --11 1111
05h
PORTA
TRISA
—
—
—
—
RA5
RA4
RA3
RA1
RA0
85h
PORTA Data Direction Register
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used for A/D conversion.
DS30390E-page 126
1997 Microchip Technology Inc.
PIC16C7X
TABLE 13-3: SUMMARY OF A/D REGISTERS, PIC16C73/73A/74/74A/76/77
Value on:
POR,
BOR
Value on all
other Resets
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
T0IF
Bit 1
Bit 0
INTCON
GIE
PEIE
T0IE
INTE
RBIE
INTF
RBIF
0000 000x 0000 000u
0Bh,8Bh,
10Bh,18Bh
(1)
PIR1
PSPIF
PSPIE
—
ADIF
ADIE
—
RCIF
RCIE
—
TXIF
TXIE
—
SSPIF
SSPIE
—
CCP1IF
TMR2IF TMR1IF 0000 0000 0000 0000
0Ch
8Ch
0Dh
8Dh
1Eh
1Fh
9Fh
05h
85h
09h
89h
(1)
PIE1
CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
PIR2
—
—
—
—
CCP2IF ---- ---0 ---- ---0
CCP2IE ---- ---0 ---- ---0
xxxx xxxx uuuu uuuu
PIE2
—
—
—
—
—
ADRES
A/D Result Register
ADCON0 ADCS1 ADCS0 CHS2
CHS1
—
CHS0 GO/DONE
—
ADON 0000 00-0 0000 00-0
ADCON1
—
—
—
—
—
—
PCFG2
RA2
PCFG1 PCFG0 ---- -000 ---- -000
--0x 0000 --0u 0000
--11 1111 --11 1111
---- -xxx ---- -uuu
0000 -111 0000 -111
PORTA
TRISA
PORTE
TRISE
RA5
RA4
RA3
RA1
RA0
—
—
—
—
PORTA Data Direction Register
—
—
—
—
RE2
RE1
RE0
IBF
OBF
IBOV PSPMODE
PORTE Data Direction Bits
Legend: x= unknown, u= unchanged, -= unimplemented read as '0'. Shaded cells are not used for A/D conversion.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC6C73/73A/76, always maintain these bits clear.
1997 Microchip Technology Inc.
DS30390E-page 127
PIC16C7X
NOTES:
DS30390E-page 128
1997 Microchip Technology Inc.
PIC16C7X
the chip in reset until the crystal oscillator is stable.The
other is the Power-up Timer (PWRT), which provides a
fixed delay of 72 ms (nominal) on power-up only,
designed to keep the part in reset while the power sup-
ply stabilizes. With these two timers on-chip, most
applications need no external reset circuitry.
14.0 SPECIAL FEATURES OF THE
CPU
Applicable Devices
72 73 73A 74 74A 76 77
What sets a microcontroller apart from other proces-
sors are special circuits to deal with the needs of real-
time applications. The PIC16CXX family has a host of
such features intended to maximize system reliability,
minimize cost through elimination of external compo-
nents, provide power saving operating modes and offer
code protection. These are:
SLEEP mode is designed to offer a very low current
power-down mode.The user can wake-up from SLEEP
through external reset, Watchdog Timer Wake-up, or
through an interrupt. Several oscillator options are also
made available to allow the part to fit the application.
The RC oscillator option saves system cost while the
LP crystal option saves power. A set of configuration
bits are used to select various options.
• Oscillator selection
• Reset
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
14.1
Configuration Bits
Applicable Devices
72 73 73A 74 74A 76 77
The configuration bits can be programmed (read as '0')
or left unprogrammed (read as '1') to select various
device configurations. These bits are mapped in pro-
gram memory location 2007h.
• Watchdog Timer (WDT)
• SLEEP
• Code protection
The user will note that address 2007h is beyond the
user program memory space. In fact, it belongs to the
special test/configuration memory space (2000h -
3FFFh), which can be accessed only during program-
ming.
• ID locations
• In-circuit serial programming
The PIC16CXX has a Watchdog Timer which can be
shut off only through configuration bits. It runs off its
own RC oscillator for added reliability. There are two
timers that offer necessary delays on power-up. One is
the Oscillator Start-up Timer (OST), intended to keep
FIGURE 14-1: CONFIGURATION WORD FOR PIC16C73/74
—
—
—
—
—
—
—
—
CP1
CP0 PWRTE WDTE FOSC1 FOSC0
bit0
Register: CONFIG
Address 2007h
bit13
bit 13-5: Unimplemented: Read as '1'
bit 4:
CP1:CP0: Code protection bits
11= Code protection off
10= Upper half of program memory code protected
01= Upper 3/4th of program memory code protected
00= All memory is code protected
bit 3:
bit 2:
PWRTE: Power-up Timer Enable bit
1 = Power-up Timer enabled
0 = Power-up Timer disabled
WDTE: Watchdog Timer Enable bit
1 = WDT enabled
0 = WDT disabled
bit 1-0: FOSC1:FOSC0: Oscillator Selection bits
11= RC oscillator
10= HS oscillator
01= XT oscillator
00= LP oscillator
1997 Microchip Technology Inc.
DS30390E-page 129
PIC16C7X
FIGURE 14-2: CONFIGURATION WORD FOR PIC16C72/73A/74A/76/77
CP1
CP0
CP1
CP0
CP1
CP0
—
BODEN CP1
CP0 PWRTE WDTE FOSC1 FOSC0
bit0
Register: CONFIG
Address 2007h
bit13
(2)
bit 13-8 CP1:CP0: Code Protection bits
5-4: 11= Code protection off
10= Upper half of program memory code protected
01= Upper 3/4th of program memory code protected
00= All memory is code protected
bit 7:
bit 6:
Unimplemented: Read as '1'
(1)
BODEN: Brown-out Reset Enable bit
1 = BOR enabled
0 = BOR disabled
(1)
bit 3:
bit 2:
PWRTE: Power-up Timer Enable bit
1 = PWRT disabled
0 = PWRT enabled
WDTE: Watchdog Timer Enable bit
1 = WDT enabled
0 = WDT disabled
bit 1-0: FOSC1:FOSC0: Oscillator Selection bits
11= RC oscillator
10= HS oscillator
01= XT oscillator
00= LP oscillator
Note 1: Enabling Brown-out Reset automatically enables Power-up Timer (PWRT) regardless of the value of bit PWRTE.
Ensure the Power-up Timer is enabled anytime Brown-out Reset is enabled.
2: All of the CP1:CP0 pairs have to be given the same value to enable the code protection scheme listed.
DS30390E-page 130
1997 Microchip Technology Inc.
PIC16C7X
14.2
Oscillator Configurations
Applicable Devices
TABLE 14-1: CERAMIC RESONATORS
Ranges Tested:
72 73 73A 74 74A 76 77
Mode
XT
Freq
OSC1
OSC2
14.2.1
OSCILLATOR TYPES
455 kHz
2.0 MHz
4.0 MHz
68 - 100 pF
15 - 68 pF
15 - 68 pF
68 - 100 pF
15 - 68 pF
15 - 68 pF
The PIC16CXX can be operated in four different oscil-
lator modes. The user can program two configuration
bits (FOSC1 and FOSC0) to select one of these four
modes:
HS
8.0 MHz
16.0 MHz
10 - 68 pF
10 - 22 pF
10 - 68 pF
10 - 22 pF
These values are for design guidance only. See
notes at bottom of page.
• LP
• XT
• HS
• RC
Low Power Crystal
Crystal/Resonator
Resonators Used:
High Speed Crystal/Resonator
Resistor/Capacitor
455 kHz Panasonic EFO-A455K04B ± 0.3%
2.0 MHz Murata Erie CSA2.00MG
4.0 MHz Murata Erie CSA4.00MG
8.0 MHz Murata Erie CSA8.00MT
16.0 MHz Murata Erie CSA16.00MX
± 0.5%
± 0.5%
± 0.5%
± 0.5%
14.2.2 CRYSTAL OSCILLATOR/CERAMIC
RESONATORS
In XT, LP or HS modes a crystal or ceramic resonator
is connected to the OSC1/CLKIN and OSC2/CLKOUT
pins to establish oscillation (Figure 14-3). The
PIC16CXX Oscillator design requires the use of a par-
allel cut crystal. Use of a series cut crystal may give a
frequency out of the crystal manufacturers specifica-
tions. When in XT, LP or HS modes, the device can
have an external clock source to drive the OSC1/
CLKIN pin (Figure 14-4).
All resonators used did not have built-in capacitors.
TABLE 14-2: CAPACITOR SELECTION
FOR CRYSTAL OSCILLATOR
Crystal
Freq
Cap. Range
C1
Cap. Range
C2
Osc Type
LP
32 kHz
200 kHz
200 kHz
1 MHz
33 pF
15 pF
33 pF
15 pF
FIGURE 14-3: CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS, XT OR LP
XT
HS
47-68 pF
15 pF
47-68 pF
15 pF
OSC CONFIGURATION)
4 MHz
15 pF
15 pF
OSC1
4 MHz
15 pF
15 pF
To internal
logic
8 MHz
15-33 pF
15-33 pF
15-33 pF
15-33 pF
C1
20 MHz
XTAL
OSC2
SLEEP
PIC16CXX
RF
These values are for design guidance only. See
notes at bottom of page.
RS
Crystals Used
C2
Note1
32 kHz
200 kHz
1 MHz
Epson C-001R32.768K-A
STD XTL 200.000KHz
ECS ECS-10-13-1
± 20 PPM
± 20 PPM
± 50 PPM
± 50 PPM
± 30 PPM
± 30 PPM
See Table 14-1 and Table 14-2 for recommended values
of C1 and C2.
Note 1: A series resistor may be required for AT strip
cut crystals.
4 MHz
ECS ECS-40-20-1
8 MHz
EPSON CA-301 8.000M-C
EPSON CA-301 20.000M-C
20 MHz
FIGURE 14-4: EXTERNAL CLOCK INPUT
OPERATION (HS, XT OR LP
Note 1: Recommended values of C1 and C2 are
identical to the ranges tested (Table 14-1).
2: Higher capacitance increases the stability
of oscillator but also increases the start-up
time.
OSC CONFIGURATION)
OSC1
OSC2
Clock from
ext. system
PIC16CXX
3: Since each resonator/crystal has its own
characteristics, the user should consult the
resonator/crystal manufacturer for appropri-
ate values of external components.
Open
4: Rs may be required in HS mode as well as
XT mode to avoid overdriving crystals with
low drive level specification.
1997 Microchip Technology Inc.
DS30390E-page 131
PIC16C7X
14.2.3 EXTERNAL CRYSTAL OSCILLATOR
CIRCUIT
14.2.4 RC OSCILLATOR
For timing insensitive applications the “RC” device
option offers additional cost savings. The RC oscillator
frequency is a function of the supply voltage, the resis-
tor (Rext) and capacitor (Cext) values, and the operat-
ing temperature. In addition to this, the oscillator
frequency will vary from unit to unit due to normal pro-
cess parameter variation. Furthermore, the difference
in lead frame capacitance between package types will
also affect the oscillation frequency, especially for low
Cext values. The user also needs to take into account
variation due to tolerance of external R and C compo-
nents used. Figure 14-7 shows how the R/C combina-
tion is connected to the PIC16CXX. For Rext values
below 2.2 kΩ, the oscillator operation may become
unstable, or stop completely. For very high Rext values
(e.g. 1 MΩ), the oscillator becomes sensitive to noise,
humidity and leakage. Thus, we recommend to keep
Rext between 3 kΩ and 100 kΩ.
Either a prepackaged oscillator can be used or a simple
oscillator circuit with TTL gates can be built. Prepack-
aged oscillators provide a wide operating range and
better stability. A well-designed crystal oscillator will
provide good performance with TTL gates. Two types
of crystal oscillator circuits can be used; one with series
resonance, or one with parallel resonance.
Figure 14-5 shows implementation of a parallel reso-
nant oscillator circuit. The circuit is designed to use the
fundamental frequency of the crystal. The 74AS04
inverter performs the 180-degree phase shift that a par-
allel oscillator requires. The 4.7 kΩ resistor provides
the negative feedback for stability. The 10 kΩ potenti-
ometer biases the 74AS04 in the linear region. This
could be used for external oscillator designs.
FIGURE 14-5: EXTERNAL PARALLEL
RESONANT CRYSTAL
Although the oscillator will operate with no external
capacitor (Cext = 0 pF), we recommend using values
above 20 pF for noise and stability reasons. With no or
small external capacitance, the oscillation frequency
can vary dramatically due to changes in external
capacitances, such as PCB trace capacitance or pack-
age lead frame capacitance.
OSCILLATOR CIRCUIT
+5V
To Other
Devices
10k
74AS04
PIC16CXX
4.7k
CLKIN
74AS04
See characterization data for desired device for RC fre-
quency variation from part to part due to normal pro-
cess variation.The variation is larger for larger R (since
leakage current variation will affect RC frequency more
for large R) and for smaller C (since variation of input
capacitance will affect RC frequency more).
10k
XTAL
10k
See characterization data for desired device for varia-
tion of oscillator frequency due to VDD for given Rext/
Cext values as well as frequency variation due to oper-
ating temperature for given R, C, and VDD values.
20 pF
20 pF
Figure 14-6 shows a series resonant oscillator circuit.
This circuit is also designed to use the fundamental fre-
quency of the crystal. The inverter performs a 180-
degree phase shift in a series resonant oscillator cir-
cuit. The 330 kΩ resistors provide the negative feed-
back to bias the inverters in their linear region.
The oscillator frequency, divided by 4, is available on
the OSC2/CLKOUT pin, and can be used for test pur-
poses or to synchronize other logic (see Figure 3-4 for
waveform).
FIGURE 14-7: RC OSCILLATOR MODE
FIGURE 14-6: EXTERNAL SERIES
RESONANT CRYSTAL
VDD
OSCILLATOR CIRCUIT
Rext
Internal
OSC1
To Other
clock
Devices
330 kΩ
330 kΩ
Cext
74AS04
74AS04
74AS04
PIC16CXX
PIC16CXX
VSS
CLKIN
0.1 µF
OSC2/CLKOUT
Fosc/4
XTAL
DS30390E-page 132
1997 Microchip Technology Inc.
PIC16C7X
A simplified block diagram of the on-chip reset circuit is
shown in Figure 14-8.
14.3
Reset
Applicable Devices
72 73 73A 74 74A 76 77
The PIC16C72/73A/74A/76/77 have a MCLR noise fil-
ter in the MCLR reset path. The filter will detect and
ignore small pulses.
The PIC16CXX differentiates between various kinds of
reset:
It should be noted that a WDT Reset does not drive
MCLR pin low.
• Power-on Reset (POR)
• MCLR reset during normal operation
• MCLR reset during SLEEP
• WDT Reset (normal operation)
• Brown-out Reset (BOR) (PIC16C72/73A/74A/76/
77)
Some registers are not affected in any reset condition;
their status is unknown on POR and unchanged in any
other reset. Most other registers are reset to a “reset
state” on Power-on Reset (POR), on the MCLR and
WDT Reset, on MCLR reset during SLEEP, and Brown-
out Reset (BOR). They are not affected by a WDT
Wake-up, which is viewed as the resumption of normal
operation.The TO and PD bits are set or cleared differ-
ently in different reset situations as indicated in
Table 14-5 and Table 14-6. These bits are used in soft-
ware to determine the nature of the reset. See
Table 14-8 for a full description of reset states of all reg-
isters.
FIGURE 14-8: SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
External
Reset
MCLR
SLEEP
WDT
WDT
Module
Time-out
Reset
VDD rise
detect
Power-on Reset
VDD
(2)
Brown-out
Reset
S
R
BODEN
OST/PWRT
OST
10-bit Ripple counter
Chip_Reset
Q
OSC1
(1)
On-chip
RC OSC
PWRT
10-bit Ripple counter
Enable PWRT
(3)
Enable OST
Note 1: This is a separate oscillator from the RC oscillator of the CLKIN pin.
2: Brown-out Reset is implemented on the PIC16C72/73A/74A/76/77.
3: See Table 14-3 and Table 14-4 for time-out situations.
1997 Microchip Technology Inc.
DS30390E-page 133
PIC16C7X
The power-up time delay will vary from chip to chip due
to VDD, temperature, and process variation. See DC
parameters for details.
14.4
Power-on Reset (POR), Power-up
Timer (PWRT) and Oscillator Start-up
Timer (OST), and Brown-out Reset
(BOR)
14.4.3 OSCILLATOR START-UP TIMER (OST)
Applicable Devices
The Oscillator Start-up Timer (OST) provides 1024
oscillator cycle (from OSC1 input) delay after the
PWRT delay is over.This ensures that the crystal oscil-
lator or resonator has started and stabilized.
72 73 73A 74 74A 76 77
14.4.1 POWER-ON RESET (POR)
A Power-on Reset pulse is generated on-chip when
VDD rise is detected (in the range of 1.5V - 2.1V). To
take advantage of the POR, just tie the MCLR pin
directly (or through a resistor) to VDD. This will elimi-
nate external RC components usually needed to create
a Power-on Reset. A maximum rise time for VDD is
specified. See Electrical Specifications for details.
The OST time-out is invoked only for XT, LP and HS
modes and only on Power-on Reset or wake-up from
SLEEP.
14.4.4 BROWN-OUT RESET (BOR)
Applicable Devices
72 73 73A 74 74A 76 77
When the device starts normal operation (exits the
reset condition), device operating parameters (voltage,
frequency, temperature, ...) must be met to ensure
operation. If these conditions are not met, the device
must be held in reset until the operating conditions are
met. Brown-out Reset may be used to meet the startup
conditions.
A configuration bit, BODEN, can disable (if clear/pro-
grammed) or enable (if set) the Brown-out Reset cir-
cuitry. If VDD falls below 4.0V (3.8V - 4.2V range) for
greater than parameter #35, the brown-out situation will
reset the chip. A reset may not occur if VDD falls below
4.0V for less than parameter #35. The chip will remain
in Brown-out Reset until VDD rises above BVDD. The
Power-up Timer will now be invoked and will keep the
chip in RESET an additional 72 ms. If VDD drops below
BVDD while the Power-up Timer is running, the chip will
go back into a Brown-out Reset and the Power-up
Timer will be initialized. Once VDD rises above BVDD,
the Power-up Timer will execute a 72 ms time delay.
The Power-up Timer should always be enabled when
Brown-out Reset is enabled. Figure 14-9 shows typi-
cal brown-out situations.
For additional information, refer to Application Note
AN607, "Power-up Trouble Shooting."
14.4.2 POWER-UP TIMER (PWRT)
The Power-up Timer provides a fixed 72 ms nominal
time-out on power-up only, from the POR. The Power-
up Timer operates on an internal RC oscillator. The
chip is kept in reset as long as the PWRT is active. The
PWRT’s time delay allows VDD to rise to an acceptable
level. A configuration bit is provided to enable/disable
the PWRT.
FIGURE 14-9: BROWN-OUT SITUATIONS
VDD
BVDD Max.
BVDD Min.
Internal
Reset
72 ms
VDD
BVDD Max.
BVDD Min.
Internal
Reset
<72 ms
72 ms
VDD
BVDD Max.
BVDD Min.
Internal
Reset
72 ms
DS30390E-page 134
1997 Microchip Technology Inc.
PIC16C7X
14.4.5 TIME-OUT SEQUENCE
14.4.6 POWER CONTROL/STATUS REGISTER
(PCON)
On power-up the time-out sequence is as follows: First
PWRT time-out is invoked after the POR time delay has
expired. Then OST is activated. The total time-out will
vary based on oscillator configuration and the status of
the PWRT. For example, in RC mode with the PWRT
disabled, there will be no time-out at all. Figure 14-10,
Figure 14-11, and Figure 14-12 depict time-out
sequences on power-up.
Applicable Devices
72 73 73A 74 74A 76 77
The Power Control/Status Register, PCON has up to
two bits, depending upon the device. Bit0 is not imple-
mented on the PIC16C73 or PIC16C74.
Bit0 is Brown-out Reset Status bit, BOR. Bit BOR is
unknown on a Power-on Reset. It must then be set by
the user and checked on subsequent resets to see if bit
BOR cleared, indicating a BOR occurred. The BOR bit
is a "Don’t Care" bit and is not necessarily predictable
if the Brown-out Reset circuitry is disabled (by clearing
bit BODEN in the Configuration Word).
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the time-outs will expire. Then
bringing MCLR high will begin execution immediately
(Figure 14-11). This is useful for testing purposes or to
synchronize more than one PIC16CXX device operat-
ing in parallel.
Bit1 is POR (Power-on Reset Status bit). It is cleared
on a Power-on Reset and unaffected otherwise. The
user must set this bit following a Power-on Reset.
Table 14-7 shows the reset conditions for some special
function registers, while Table 14-8 shows the reset
conditions for all the registers.
TABLE 14-3: TIME-OUT IN VARIOUS SITUATIONS, PIC16C73/74
Oscillator Configuration
Power-up
Wake-up from SLEEP
PWRTE = 1
PWRTE = 0
1024TOSC
—
XT, HS, LP
RC
72 ms + 1024TOSC
72 ms
1024 TOSC
—
TABLE 14-4: TIME-OUT IN VARIOUS SITUATIONS, PIC16C72/73A/74A/76/77
Oscillator Configuration
Power-up
PWRTE = 0
Wake-up from SLEEP
Brown-out
PWRTE = 1
1024TOSC
—
XT, HS, LP
RC
72 ms + 1024TOSC
72 ms
72 ms + 1024TOSC
72 ms
1024TOSC
—
TABLE 14-5: STATUS BITS AND THEIR SIGNIFICANCE, PIC16C73/74
POR
TO
PD
0
0
0
1
1
1
1
1
0
x
0
0
u
1
1
x
0
1
0
u
0
Power-on Reset
Illegal, TO is set on POR
Illegal, PD is set on POR
WDT Reset
WDT Wake-up
MCLR Reset during normal operation
MCLR Reset during SLEEP or interrupt wake-up from SLEEP
Legend: u= unchanged, x= unknown
1997 Microchip Technology Inc.
DS30390E-page 135
PIC16C7X
TABLE 14-6: STATUS BITS AND THEIR SIGNIFICANCE, PIC16C72/73A/74A/76/77
POR
BOR
TO
PD
0
0
0
1
1
1
1
1
x
x
x
0
1
1
1
1
1
0
x
x
0
0
u
1
1
x
0
x
1
0
u
0
Power-on Reset
Illegal, TO is set on POR
Illegal, PD is set on POR
Brown-out Reset
WDT Reset
WDT Wake-up
MCLR Reset during normal operation
MCLR Reset during SLEEP or interrupt wake-up from SLEEP
TABLE 14-7: RESET CONDITION FOR SPECIAL REGISTERS
Program
Counter
STATUS
Register
PCON
Register
PCON
Register
Condition
PIC16C73/74
PIC16C72/73A/74A/76/77
Power-on Reset
000h
000h
000h
000h
PC + 1
000h
0001 1xxx
000u uuuu
0001 0uuu
0000 1uuu
uuu0 0uuu
0001 1uuu
uuu1 0uuu
---- --0-
---- --u-
---- --u-
---- --u-
---- --u-
N/A
---- --0x
---- --uu
---- --uu
---- --uu
---- --uu
---- --u0
---- --uu
MCLR Reset during normal operation
MCLR Reset during SLEEP
WDT Reset
WDT Wake-up
Brown-out Reset
(1)
Interrupt wake-up from SLEEP
PC + 1
---- --u-
Legend: u= unchanged, x= unknown, -= unimplemented bit read as '0'.
Note 1: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded
with the interrupt vector (0004h).
TABLE 14-8: INITIALIZATION CONDITIONS FOR ALL REGISTERS
Register
Applicable Devices
Power-on Reset,
Brown-out Reset
MCLR Resets
WDT Reset
Wake-up via WDT
or
Interrupt
W
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
xxxx xxxx
N/A
uuuu uuuu
N/A
uuuu uuuu
N/A
INDF
TMR0
PCL
xxxx xxxx
0000h
uuuu uuuu
0000h
uuuu uuuu
(2)
PC + 1
(3)
(3)
STATUS
72 73 73A 74 74A 76 77
0001 1xxx
000q quuu
uuuq quuu
FSR
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
xxxx xxxx
--0x 0000
xxxx xxxx
xxxx xxxx
xxxx xxxx
---- -xxx
---0 0000
uuuu uuuu
--0u 0000
uuuu uuuu
uuuu uuuu
uuuu uuuu
---- -uuu
---0 0000
uuuu uuuu
--uu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
---- -uuu
---u uuuu
PORTA
PORTB
PORTC
PORTD
PORTE
PCLATH
Legend: u = unchanged, x = unknown, -= unimplemented bit, read as '0', q= value depends on condition
Note 1: One or more bits in INTCON, PIR1 and/or PIR2 will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector
(0004h).
3: See Table 14-7 for reset value for specific condition.
DS30390E-page 136
1997 Microchip Technology Inc.
PIC16C7X
TABLE 14-8: INITIALIZATION CONDITIONS FOR ALL REGISTERS (Cont.’d)
Register
Applicable Devices
Power-on Reset,
Brown-out Reset
MCLR Resets
WDT Reset
Wake-up via WDT
or
Interrupt
(1)
INTCON
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
0000 000x
-0-- 0000
-000 0000
0000 0000
---- ---0
0000 000u
-0-- 0000
-000 0000
0000 0000
---- ---0
uuuu uuuu
(1)
-u-- uuuu
(1)
PIR1
PIR2
-uuu uuuu
(1)
uuuu uuuu
(1)
---- ---u
TMR1L
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
xxxx xxxx
xxxx xxxx
--00 0000
0000 0000
-000 0000
xxxx xxxx
0000 0000
xxxx xxxx
xxxx xxxx
--00 0000
0000 -00x
0000 0000
0000 0000
xxxx xxxx
xxxx xxxx
0000 0000
xxxx xxxx
0000 00-0
1111 1111
--11 1111
1111 1111
1111 1111
1111 1111
0000 -111
-0-- 0000
-000 0000
0000 0000
---- ---0
---- --0-
---- --0u
1111 1111
uuuu uuuu
uuuu uuuu
--uu uuuu
0000 0000
-000 0000
uuuu uuuu
0000 0000
uuuu uuuu
uuuu uuuu
--00 0000
0000 -00x
0000 0000
0000 0000
uuuu uuuu
uuuu uuuu
0000 0000
uuuu uuuu
0000 00-0
1111 1111
--11 1111
1111 1111
1111 1111
1111 1111
0000 -111
-0-- 0000
-000 0000
0000 0000
---- ---0
---- --u-
---- --uu
1111 1111
uuuu uuuu
uuuu uuuu
--uu uuuu
uuuu uuuu
-uuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
--uu uuuu
uuuu -uuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uu-u
uuuu uuuu
--uu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu -uuu
-u-- uuuu
-uuu uuuu
uuuu uuuu
---- ---u
---- --u-
---- --uu
1111 1111
TMR1H
T1CON
TMR2
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON 72 73 73A 74 74A 76 77
RCSTA
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
TXREG
RCREG
CCPR2L
CCPR2H
CCP2CON 72 73 73A 74 74A 76 77
ADRES
ADCON0
OPTION
TRISA
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
TRISB
TRISC
TRISD
TRISE
PIE1
PIE2
PCON
PR2
Legend: u = unchanged, x = unknown, -= unimplemented bit, read as '0', q= value depends on condition
Note 1: One or more bits in INTCON, PIR1 and/or PIR2 will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector
(0004h).
3: See Table 14-7 for reset value for specific condition.
1997 Microchip Technology Inc.
DS30390E-page 137
PIC16C7X
TABLE 14-8: INITIALIZATION CONDITIONS FOR ALL REGISTERS (Cont.’d)
Register
Applicable Devices
Power-on Reset,
Brown-out Reset
MCLR Resets
WDT Reset
Wake-up via WDT
or
Interrupt
SSPADD
SSPSTAT
TXSTA
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
72 73 73A 74 74A 76 77
0000 0000
--00 0000
0000 -010
0000 0000
---- -000
0000 0000
--00 0000
0000 -010
0000 0000
---- -000
uuuu uuuu
--uu uuuu
uuuu -uuu
uuuu uuuu
---- -uuu
SPBRG
ADCON1
Legend: u = unchanged, x = unknown, -= unimplemented bit, read as '0', q= value depends on condition
Note 1: One or more bits in INTCON, PIR1 and/or PIR2 will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector
(0004h).
3: See Table 14-7 for reset value for specific condition.
DS30390E-page 138
1997 Microchip Technology Inc.
PIC16C7X
FIGURE 14-10: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
OST TIME-OUT
TOST
INTERNAL RESET
FIGURE 14-11: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
FIGURE 14-12: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD)
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
1997 Microchip Technology Inc.
DS30390E-page 139
PIC16C7X
FIGURE 14-13: EXTERNAL POWER-ON
RESET CIRCUIT (FOR SLOW
VDD POWER-UP)
FIGURE 14-14: EXTERNAL BROWN-OUT
PROTECTION CIRCUIT 1
VDD
VDD
33k
VDD
10k
MCLR
D
R
R1
40k
PIC16CXX
MCLR
PIC16CXX
C
Note 1: This circuit will activate reset when VDD
goes below (Vz + 0.7V) where Vz = Zener
voltage.
Note 1: External Power-on Reset circuit is required
only if VDD power-up slope is too slow.The
diode D helps discharge the capacitor
quickly when VDD powers down.
2: Internal brown-out detection on the
PIC16C72/73A/74A/76/77 should be dis-
abled when using this circuit.
2: R < 40 kΩ is recommended to make sure
that voltage drop across R does not violate
the device’s electrical specification.
3: Resistors should be adjusted for the char-
acteristics of the transistor.
3: R1 = 100Ω to 1 kΩ will limit any current
flowing into MCLR from external capacitor
C in the event of MCLR/VPP pin break-
down due to Electrostatic Discharge
(ESD) or Electrical Overstress (EOS).
FIGURE 14-15: EXTERNAL BROWN-OUT
PROTECTION CIRCUIT 2
VDD
VDD
R1
R2
Q1
MCLR
40k
PIC16CXX
Note 1: This brown-out circuit is less expensive,
albeit less accurate. Transistor Q1 turns
off when VDD is below a certain level
such that:
R1
= 0.7V
VDD •
R1 + R2
2: Internal brown-out detection on the
PIC16C72/73A/74A/76/77 should be
disabled when using this circuit.
3: Resistors should be adjusted for the
characteristics of the transistor.
DS30390E-page 140
1997 Microchip Technology Inc.
PIC16C7X
instructions. Individual interrupt flag bits are set regard-
less of the status of their corresponding mask bit or the
GIE bit.
14.5
Interrupts
Applicable Devices
72 73 73A 74 74A 76 77
Note: For the PIC16C73/74, if an interrupt occurs
while the Global Interrupt Enable (GIE) bit
is being cleared, the GIE bit may uninten-
tionally be re-enabled by the user’s Inter-
rupt Service Routine (the RETFIE
instruction). The events that would cause
this to occur are:
The PIC16C7X family has up to 12 sources of interrupt.
The interrupt control register (INTCON) records individ-
ual interrupt requests in flag bits. It also has individual
and global interrupt enable bits.
Note: Individual interrupt flag bits are set regard-
less of the status of their corresponding
mask bit or the GIE bit.
1. An instruction clears the GIE bit while
an interrupt is acknowledged.
A global interrupt enable bit, GIE (INTCON<7>)
enables (if set) all un-masked interrupts or disables (if
cleared) all interrupts. When bit GIE is enabled, and an
interrupt’s flag bit and mask bit are set, the interrupt will
vector immediately. Individual interrupts can be dis-
abled through their corresponding enable bits in vari-
ous registers. Individual interrupt bits are set
regardless of the status of the GIE bit. The GIE bit is
cleared on reset.
2. The program branches to the Interrupt
vector and executes the Interrupt Ser-
vice Routine.
3. The Interrupt Service Routine com-
pletes with the execution of the RET-
FIE instruction. This causes the GIE
bit to be set (enables interrupts), and
the program returns to the instruction
after the one which was meant to dis-
able interrupts.
The “return from interrupt” instruction, RETFIE, exits
the interrupt routine as well as sets the GIE bit, which
re-enables interrupts.
Perform the following to ensure that inter-
rupts are globally disabled:
The RB0/INT pin interrupt, the RB port change interrupt
and the TMR0 overflow interrupt flags are contained in
the INTCON register.
LOOP BCF
INTCON, GIE ; Disable global
interrupt bit
BTFSC INTCON, GIE ; Global interrupt
disabled?
; NO, try again
;
The peripheral interrupt flags are contained in the spe-
cial function registers PIR1 and PIR2. The correspond-
ing interrupt enable bits are contained in special
function registers PIE1 and PIE2, and the peripheral
interrupt enable bit is contained in special function reg-
ister INTCON.
;
GOTO LOOP
:
;
;
;
Yes, continue
with program
flow
When an interrupt is responded to, the GIE bit is
cleared to disable any further interrupt, the return
address is pushed onto the stack and the PC is loaded
with 0004h. Once in the interrupt service routine the
source(s) of the interrupt can be determined by polling
the interrupt flag bits. The interrupt flag bit(s) must be
cleared in software before re-enabling interrupts to
avoid recursive interrupts.
For external interrupt events, such as the INT pin or
PORTB change interrupt, the interrupt latency will be
three or four instruction cycles. The exact latency
depends when the interrupt event occurs (Figure 14-
17). The latency is the same for one or two cycle
1997 Microchip Technology Inc.
DS30390E-page 141
PIC16C7X
FIGURE 14-16: INTERRUPT LOGIC
PSPIF
PSPIE
Wake-up (If in SLEEP mode)
Interrupt to CPU
ADIF
ADIE
T0IF
T0IE
RCIF
RCIE
INTF
INTE
TXIF
TXIE
RBIF
RBIE
SSPIF
SSPIE
PEIE
GIE
CCP1IF
CCP1IE
TMR2IF
TMR2IE
TMR1IF
TMR1IE
CCP2IF
CCP2IE
The following table shows which devices have which interrupts.
Device
T0IF INTF RBIF PSPIF ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF CCP2IF
PIC16C72
PIC16C73
PIC16C73A
PIC16C74
PIC16C74A
PIC16C76
PIC16C77
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
-
Yes
Yes
Yes
Yes
Yes
Yes
Yes
-
-
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
-
-
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
-
Yes
Yes
Yes
Yes
FIGURE 14-17: INT PIN INTERRUPT TIMING
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
CLKOUT
3
4
INT pin
1
1
Interrupt Latency
INTF flag
(INTCON<1>)
5
2
GIE bit
(INTCON<7>)
INSTRUCTION FLOW
PC
0004h
PC+1
PC+1
—
0005h
PC
Instruction
fetched
Inst (PC)
Inst (PC+1)
Inst (0004h)
Inst (0005h)
Inst (0004h)
Instruction
executed
Dummy Cycle
Dummy Cycle
Inst (PC)
Inst (PC-1)
Note
1: INTF flag is sampled here (every Q1).
2: Interrupt latency = 3-4 Tcy where Tcy = instruction cycle time.
Latency is the same whether Inst (PC) is a single cycle or a 2-cycle instruction.
3: CLKOUT is available only in RC oscillator mode.
4: For minimum width of INT pulse, refer to AC specs.
5: INTF is enabled to be set anytime during the Q4-Q1 cycles.
DS30390E-page 142
1997 Microchip Technology Inc.
PIC16C7X
14.5.1 INT INTERRUPT
14.6
Context Saving During Interrupts
Applicable Devices
External interrupt on RB0/INT pin is edge triggered:
either rising if bit INTEDG (OPTION<6>) is set, or fall-
ing, if the INTEDG bit is clear. When a valid edge
appears on the RB0/INT pin, flag bit INTF
(INTCON<1>) is set. This interrupt can be disabled by
clearing enable bit INTE (INTCON<4>). Flag bit INTF
must be cleared in software in the interrupt service rou-
tine before re-enabling this interrupt. The INT interrupt
can wake-up the processor from SLEEP, if bit INTE was
set prior to going into SLEEP.The status of global inter-
rupt enable bit GIE decides whether or not the proces-
sor branches to the interrupt vector following wake-up.
See Section 14.8 for details on SLEEP mode.
72 73 73A 74 74A 76 77
During an interrupt, only the return PC value is saved
on the stack. Typically, users may wish to save key reg-
isters during an interrupt i.e., W register and STATUS
register. This will have to be implemented in software.
Example 14-1 stores and restores the STATUS, W, and
PCLATH registers. The register, W_TEMP, must be
defined in each bank and must be defined at the same
offset from the bank base address (i.e., if W_TEMP is
defined at 0x20 in bank 0, it must also be defined at
0xA0 in bank 1).
The example:
14.5.2 TMR0 INTERRUPT
a) Stores the W register.
b) Stores the STATUS register in bank 0.
c) Stores the PCLATH register.
d) Executes the ISR code.
An overflow (FFh → 00h) in the TMR0 register will set
flag bit T0IF (INTCON<2>). The interrupt can be
enabled/disabled by setting/clearing enable bit T0IE
(INTCON<5>). (Section 7.0)
e) Restores the STATUS register (and bank select
bit).
14.5.3 PORTB INTCON CHANGE
f) Restores the W and PCLATH registers.
An input change on PORTB<7:4> sets flag bit RBIF
(INTCON<0>). The interrupt can be enabled/disabled
by setting/clearing enable bit RBIE (INTCON<4>).
(Section 5.2)
Note: For the PIC16C73/74, if a change on the
I/O pin should occur when the read opera-
tion is being executed (start of the Q2
cycle), then the RBIF interrupt flag may not
get set.
EXAMPLE 14-1: SAVING STATUS, W, AND PCLATH REGISTERS IN RAM
MOVWF
SWAPF
CLRF
MOVWF
MOVF
MOVWF
CLRF
BCF
W_TEMP
STATUS,W
STATUS
STATUS_TEMP
PCLATH, W
PCLATH_TEMP
PCLATH
STATUS, IRP
FSR, W
;Copy W to TEMP register, could be bank one or zero
;Swap status to be saved into W
;bank 0, regardless of current bank, Clears IRP,RP1,RP0
;Save status to bank zero STATUS_TEMP register
;Only required if using pages 1, 2 and/or 3
;Save PCLATH into W
;Page zero, regardless of current page
;Return to Bank 0
;Copy FSR to W
MOVF
MOVWF
:
FSR_TEMP
;Copy FSR from W to FSR_TEMP
:(ISR)
:
MOVF
MOVWF
SWAPF
PCLATH_TEMP, W
PCLATH
STATUS_TEMP,W
;Restore PCLATH
;Move W into PCLATH
;Swap STATUS_TEMP register into W
;(sets bank to original state)
;Move W into STATUS register
;Swap W_TEMP
MOVWF
SWAPF
SWAPF
STATUS
W_TEMP,F
W_TEMP,W
;Swap W_TEMP into W
1997 Microchip Technology Inc.
DS30390E-page 143
PIC16C7X
prescaler with a division ratio of up to 1:128 can be
assigned to the WDT under software control by writing
to the OPTION register. Thus, time-out periods up to
2.3 seconds can be realized.
14.7
Watchdog Timer (WDT)
Applicable Devices
72 73 73A 74 74A 76 77
The Watchdog Timer is as a free running on-chip RC
oscillator which does not require any external compo-
nents. This RC oscillator is separate from the RC oscil-
lator of the OSC1/CLKIN pin.That means that the WDT
will run, even if the clock on the OSC1/CLKIN and
OSC2/CLKOUT pins of the device has been stopped,
for example, by execution of a SLEEPinstruction. Dur-
ing normal operation, a WDT time-out generates a
device RESET (Watchdog Timer Reset). If the device is
in SLEEP mode, a WDT time-out causes the device to
wake-up and continue with normal operation (Watch-
dog Timer Wake-up). The WDT can be permanently
disabled by clearing configuration bit WDTE
(Section 14.1).
The CLRWDT and SLEEP instructions clear the WDT
and the postscaler, if assigned to the WDT, and prevent
it from timing out and generating a device RESET con-
dition.
The TO bit in the STATUS register will be cleared upon
a Watchdog Timer time-out.
14.7.2 WDT PROGRAMMING CONSIDERATIONS
It should also be taken into account that under worst
case conditions (VDD = Min., Temperature = Max., and
max. WDT prescaler) it may take several seconds
before a WDT time-out occurs.
Note: When a CLRWDT instruction is executed
and the prescaler is assigned to the WDT,
the prescaler count will be cleared, but the
prescaler assignment is not changed.
14.7.1 WDT PERIOD
The WDT has a nominal time-out period of 18 ms, (with
no prescaler). The time-out periods vary with tempera-
DD
ture, V and process variations from part to part (see
DC specs). If longer time-out periods are desired, a
FIGURE 14-18: WATCHDOG TIMER BLOCK DIAGRAM
From TMR0 Clock Source
(Figure 7-6)
0
Postscaler
8
M
1
U
WDT Timer
X
8 - to - 1 MUX
PS2:PS0
PSA
WDT
Enable Bit
To TMR0 (Figure 7-6)
0
1
MUX
PSA
WDT
Time-out
Note: PSA and PS2:PS0 are bits in the OPTION register.
FIGURE 14-19: SUMMARY OF WATCHDOG TIMER REGISTERS
Address
2007h
Name
Bit 7
(1)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
WDTE
PS2
Bit 1
FOSC1
PS1
Bit 0
FOSC0
PS0
(1)
(1)
Config. bits
OPTION
CP1
CP0
BODEN
PWRTE
PSA
81h,181h
RBPU
INTEDG
T0CS T0SE
Legend: Shaded cells are not used by the Watchdog Timer.
Note 1: See Figure 14-1, and Figure 14-2 for operation of these bits.
DS30390E-page 144
1997 Microchip Technology Inc.
PIC16C7X
Other peripherals cannot generate interrupts since dur-
ing SLEEP, no on-chip Q clocks are present.
14.8
Power-down Mode (SLEEP)
Applicable Devices
When the SLEEPinstruction is being executed, the next
instruction (PC + 1) is pre-fetched. For the device to
wake-up through an interrupt event, the corresponding
interrupt enable bit must be set (enabled). Wake-up is
regardless of the state of the GIE bit. If the GIE bit is
clear (disabled), the device continues execution at the
instruction after the SLEEPinstruction. If the GIE bit is
set (enabled), the device executes the instruction after
the SLEEP instruction and then branches to the inter-
rupt address (0004h). In cases where the execution of
the instruction following SLEEP is not desirable, the
user should have a NOPafter the SLEEPinstruction.
72 73 73A 74 74A 76 77
Power-down mode is entered by executing a SLEEP
instruction.
If enabled, the Watchdog Timer will be cleared but
keeps running, the PD bit (STATUS<3>) is cleared, the
TO (STATUS<4>) bit is set, and the oscillator driver is
turned off. The I/O ports maintain the status they had,
before the SLEEP instruction was executed (driving
high, low, or hi-impedance).
For lowest current consumption in this mode, place all
I/O pins at either VDD, or VSS, ensure no external cir-
cuitry is drawing current from the I/O pin, power-down
the A/D, disable external clocks. Pull all I/O pins, that
are hi-impedance inputs, high or low externally to avoid
switching currents caused by floating inputs. The
T0CKI input should also be at VDD or VSS for lowest
current consumption. The contribution from on-chip
pull-ups on PORTB should be considered.
14.8.2 WAKE-UP USING INTERRUPTS
When global interrupts are disabled (GIE cleared) and
any interrupt source has both its interrupt enable bit
and interrupt flag bit set, one of the following will occur:
• If the interrupt occurs before the execution of a
SLEEPinstruction, the SLEEPinstruction will com-
plete as a NOP. Therefore, the WDT and WDT
postscaler will not be cleared, the TO bit will not
be set and PD bits will not be cleared.
The MCLR pin must be at a logic high level (VIHMC).
14.8.1 WAKE-UP FROM SLEEP
The device can wake up from SLEEP through one of
the following events:
• If the interrupt occurs during or after the execu-
tion of a SLEEPinstruction, the device will imme-
diately wake up from sleep.The SLEEPinstruction
will be completely executed before the wake-up.
Therefore, the WDT and WDT postscaler will be
cleared, the TO bit will be set and the PD bit will
be cleared.
1. External reset input on MCLR pin.
2. Watchdog Timer Wake-up (if WDT was
enabled).
3. Interrupt from INT pin, RB port change, or some
Peripheral Interrupts.
Even if the flag bits were checked before executing a
SLEEP instruction, it may be possible for flag bits to
become set before the SLEEPinstruction completes.To
determine whether a SLEEPinstruction executed, test
the PD bit. If the PD bit is set, the SLEEP instruction
was executed as a NOP.
External MCLR Reset will cause a device reset. All
other events are considered a continuation of program
execution and cause a "wake-up". The TO and PD bits
in the STATUS register can be used to determine the
cause of device reset. The PD bit, which is set on
power-up, is cleared when SLEEP is invoked. The TO
bit is cleared if a WDT time-out occurred (and caused
wake-up).
To ensure that the WDT is cleared, a CLRWDTinstruc-
tion should be executed before a SLEEPinstruction.
The following peripheral interrupts can wake the device
from SLEEP:
1. TMR1 interrupt. Timer1 must be operating as
an asynchronous counter.
2. SSP (Start/Stop) bit detect interrupt.
2
3. SSP transmit or receive in slave mode (SPI/I C).
4. CCP capture mode interrupt.
5. Parallel Slave Port read or write.
6. A/D conversion (when A/D clock source is RC).
7. Special event trigger (Timer1 in asynchronous
mode using an external clock).
8. USART TX or RX (synchronous slave mode).
1997 Microchip Technology Inc.
DS30390E-page 145
PIC16C7X
FIGURE 14-20: WAKE-UP FROM SLEEP THROUGH INTERRUPT
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
CLKOUT(4)
INT pin
TOST(2)
INTF flag
(INTCON<1>)
Interrupt Latency
(Note 2)
GIE bit
(INTCON<7>)
Processor in
SLEEP
INSTRUCTION FLOW
PC
PC
PC+1
PC+2
PC+2
PC + 2
0004h
0005h
Instruction
Inst(0004h)
Inst(PC + 1)
Inst(PC + 2)
Inst(0005h)
Inst(PC) = SLEEP
Inst(PC - 1)
fetched
Instruction
executed
Dummy cycle
Dummy cycle
SLEEP
Inst(PC + 1)
Inst(0004h)
Note 1: XT, HS or LP oscillator mode assumed.
2: TOST = 1024TOSC (drawing not to scale) This delay will not be there for RC osc mode.
3: GIE = '1' assumed. In this case after wake- up, the processor jumps to the interrupt routine. If GIE = '0', execution will continue in-line.
4: CLKOUT is not available in these osc modes, but shown here for timing reference.
The device is placed into a program/verify mode by
holding the RB6 and RB7 pins low while raising the
MCLR (VPP) pin from VIL to VIHH (see programming
specification). RB6 becomes the programming clock
and RB7 becomes the programming data. Both RB6
and RB7 are Schmitt Trigger inputs in this mode.
14.9
Program Verification/Code Protection
Applicable Devices
72 73 73A 74 74A 76 77
If the code protection bit(s) have not been pro-
grammed, the on-chip program memory can be read
out for verification purposes.
After reset, to place the device into programming/verify
mode, the program counter (PC) is at location 00h. A 6-
bit command is then supplied to the device. Depending
on the command, 14-bits of program data are then sup-
plied to or from the device, depending if the command
was a load or a read. For complete details of serial pro-
gramming, please refer to the PIC16C6X/7X Program-
ming Specifications (Literature #DS30228).
Note: Microchip does not recommend code pro-
tecting windowed devices.
14.10 ID Locations
Applicable Devices
72 73 73A 74 74A 76 77
Four memory locations (2000h - 2003h) are designated
as ID locations where the user can store checksum or
other code-identification numbers. These locations are
not accessible during normal execution but are read-
able and writable during program/verify. It is recom-
mended that only the 4 least significant bits of the ID
location are used.
FIGURE 14-21: TYPICAL IN-CIRCUIT SERIAL
PROGRAMMING
CONNECTION
To Normal
Connections
External
Connector
Signals
PIC16CXX
14.11 In-Circuit Serial Programming
Applicable Devices
+5V
0V
VDD
72 73 73A 74 74A 76 77
VSS
PIC16CXX microcontrollers can be serially pro-
grammed while in the end application circuit. This is
simply done with two lines for clock and data, and three
other lines for power, ground, and the programming
voltage. This allows customers to manufacture boards
with unprogrammed devices, and then program the
microcontroller just before shipping the product. This
also allows the most recent firmware or a custom firm-
ware to be programmed.
VPP
MCLR/VPP
RB6
RB7
CLK
Data I/O
VDD
To Normal
Connections
DS30390E-page 146
1997 Microchip Technology Inc.
PIC16C7X
The instruction set is highly orthogonal and is grouped
into three basic categories:
15.0 INSTRUCTION SET SUMMARY
Each PIC16CXX instruction is a 14-bit word divided
into an OPCODE which specifies the instruction type
and one or more operands which further specify the
operation of the instruction. The PIC16CXX instruction
set summary in Table 15-2 lists byte-oriented, bit-ori-
ented, and literal and control operations. Table 15-1
shows the opcode field descriptions.
• Byte-oriented operations
• Bit-oriented operations
• Literal and control operations
All instructions are executed within one single instruc-
tion cycle, unless a conditional test is true or the pro-
gram counter is changed as a result of an instruction.
In this case, the execution takes two instruction cycles
with the second cycle executed as a NOP. One instruc-
tion cycle consists of four oscillator periods. Thus, for
an oscillator frequency of 4 MHz, the normal instruction
execution time is 1 µs. If a conditional test is true or the
program counter is changed as a result of an instruc-
tion, the instruction execution time is 2 µs.
For byte-oriented instructions, 'f' represents a file reg-
ister designator and 'd' represents a destination desig-
nator. The file register designator specifies which file
register is to be used by the instruction.
The destination designator specifies where the result of
the operation is to be placed. If 'd' is zero, the result is
placed in the W register. If 'd' is one, the result is placed
in the file register specified in the instruction.
Table 15-2 lists the instructions recognized by the
MPASM assembler.
For bit-oriented instructions, 'b' represents a bit field
designator which selects the number of the bit affected
by the operation, while 'f' represents the number of the
file in which the bit is located.
Figure 15-1 shows the general formats that the instruc-
tions can have.
Note: To maintain upward compatibility with
future PIC16CXX products, do not use the
OPTIONand TRISinstructions.
For literal and control operations, 'k' represents an
eight or eleven bit constant or literal value.
TABLE 15-1: OPCODE FIELD
DESCRIPTIONS
All examples use the following format to represent a
hexadecimal number:
0xhh
Field
Description
where h signifies a hexadecimal digit.
f
W
b
k
x
Register file address (0x00 to 0x7F)
Working register (accumulator)
FIGURE 15-1: GENERAL FORMAT FOR
INSTRUCTIONS
Bit address within an 8-bit file register
Literal field, constant data or label
Byte-oriented file register operations
13
8
7
6
0
0
Don't care location (= 0 or 1)
The assembler will generate code with x = 0. It is the
recommended form of use for compatibility with all
Microchip software tools.
OPCODE
d
f (FILE #)
d = 0 for destination W
d = 1 for destination f
f = 7-bit file register address
d
Destination select; d = 0: store result in W,
d = 1: store result in file register f.
Default is d = 1
Bit-oriented file register operations
13 10 9
b (BIT #)
label Label name
TOS Top of Stack
PC Program Counter
7
6
OPCODE
f (FILE #)
PCLATH
Program Counter High Latch
b = 3-bit bit address
f = 7-bit file register address
GIE Global Interrupt Enable bit
WDT Watchdog Timer/Counter
TO Time-out bit
Literal and control operations
PD Power-down bit
General
dest Destination either the W register or the specified
13
8
7
0
0
register file location
OPCODE
k (literal)
[ ] Options
Contents
( )
→
k = 8-bit immediate value
Assigned to
Register bit field
In the set of
< >
CALLand GOTOinstructions only
13 11 10
OPCODE
k = 11-bit immediate value
User defined term (font is courier)
italics
k (literal)
1997 Microchip Technology Inc.
DS30390E-page 147
PIC16C7X
TABLE 15-2: PIC16CXX INSTRUCTION SET
Mnemonic,
Operands
Description
Cycles
14-Bit Opcode
Status
Affected
Notes
MSb
LSb
BYTE-ORIENTED FILE REGISTER OPERATIONS
ADDWF
ANDWF
CLRF
CLRW
COMF
DECF
f, d
f, d
f
Add W and f
AND W with f
Clear f
Clear W
Complement f
Decrement f
Decrement f, Skip if 0
Increment f
Increment f, Skip if 0
Inclusive OR W with f
Move f
1
1
1
1
1
1
1(2)
1
1(2)
1
1
1
1
1
1
1
1
1
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
0111 dfff ffff C,DC,Z
1,2
1,2
2
0101 dfff ffff
0001 lfff ffff
0001 0xxx xxxx
1001 dfff ffff
0011 dfff ffff
1011 dfff ffff
1010 dfff ffff
1111 dfff ffff
0100 dfff ffff
1000 dfff ffff
0000 lfff ffff
0000 0xx0 0000
1101 dfff ffff
1100 dfff ffff
Z
Z
Z
Z
Z
-
f, d
f, d
f, d
f, d
f, d
f, d
f, d
f
1,2
1,2
1,2,3
1,2
1,2,3
1,2
DECFSZ
INCF
Z
INCFSZ
IORWF
MOVF
MOVWF
NOP
RLF
RRF
SUBWF
SWAPF
XORWF
Z
Z
1,2
Move W to f
No Operation
-
f, d
f, d
f, d
f, d
f, d
Rotate Left f through Carry
Rotate Right f through Carry
Subtract W from f
Swap nibbles in f
Exclusive OR W with f
C
C
1,2
1,2
1,2
1,2
1,2
0010 dfff ffff C,DC,Z
1110 dfff ffff
0110 dfff ffff Z
BIT-ORIENTED FILE REGISTER OPERATIONS
BCF
BSF
BTFSC
BTFSS
f, b
f, b
f, b
f, b
Bit Clear f
Bit Set f
Bit Test f, Skip if Clear
Bit Test f, Skip if Set
1
1
01
01
00bb bfff ffff
01bb bfff ffff
10bb bfff ffff
11bb bfff ffff
1,2
1,2
3
1 (2) 01
1 (2) 01
3
LITERAL AND CONTROL OPERATIONS
ADDLW
ANDLW
CALL
CLRWDT
GOTO
IORLW
MOVLW
RETFIE
RETLW
RETURN
SLEEP
SUBLW
XORLW
k
k
k
-
k
k
k
-
k
-
-
k
k
Add literal and W
AND literal with W
Call subroutine
Clear Watchdog Timer
Go to address
1
1
2
1
2
1
1
2
2
2
1
1
1
11
11
10
00
10
11
11
00
11
00
00
11
11
111x kkkk kkkk C,DC,Z
1001 kkkk kkkk
0kkk kkkk kkkk
Z
0000 0110 0100 TO,PD
1kkk kkkk kkkk
Inclusive OR literal with W
Move literal to W
1000 kkkk kkkk
00xx kkkk kkkk
0000 0000 1001
01xx kkkk kkkk
0000 0000 1000
Z
Return from interrupt
Return with literal in W
Return from Subroutine
Go into standby mode
Subtract W from literal
Exclusive OR literal with W
0000 0110 0011 TO,PD
110x kkkk kkkk C,DC,Z
1010 kkkk kkkk
Z
Note 1: When an I/O register is modified as a function of itself ( e.g., MOVF PORTB, 1), the value used will be that value present
on the pins themselves. For example, if the data latch is '1' for a pin configured as input and is driven low by an external
device, the data will be written back with a '0'.
2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned
to the Timer0 Module.
3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is
executed as a NOP.
DS30390E-page 148
1997 Microchip Technology Inc.
PIC16C7X
15.1
Instruction Descriptions
Add Literal and W
ANDLW
AND Literal with W
ADDLW
Syntax:
[label] ANDLW
k
Syntax:
[label] ADDLW
0 ≤ k ≤ 255
k
Operands:
Operation:
Status Affected:
Encoding:
Description:
0 ≤ k ≤ 255
Operands:
Operation:
Status Affected:
Encoding:
Description:
(W) .AND. (k) → (W)
(W) + k → (W)
C, DC, Z
Z
11
1001
kkkk
kkkk
11
111x
kkkk
kkkk
The contents of W register are
AND’ed with the eight bit literal 'k'.The
result is placed in the W register.
The contents of the W register are
added to the eight bit literal 'k' and the
result is placed in the W register.
Words:
1
1
Words:
1
1
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal "k"
Process
data
Write to
W
Decode
Read
literal 'k'
Process
data
Write to
W
ANDLW
0x5F
ADDLW
0x15
Example
Example:
Before Instruction
Before Instruction
W
=
0xA3
0x03
W
=
0x10
0x25
After Instruction
After Instruction
W
=
W
=
ADDWF
Syntax:
Add W and f
ANDWF
Syntax:
AND W with f
[label] ADDWF f,d
[label] ANDWF f,d
Operands:
0 ≤ f ≤ 127
Operands:
0 ≤ f ≤ 127
d
[0,1]
d
[0,1]
Operation:
(W) + (f) → (destination)
Operation:
(W) .AND. (f) → (destination)
Status Affected:
Encoding:
C, DC, Z
Status Affected:
Encoding:
Z
00
0111
dfff
ffff
00
0101
dfff
ffff
Add the contents of the W register with
register 'f'. If 'd' is 0 the result is stored
in the W register. If 'd' is 1 the result is
stored back in register 'f'.
AND the W register with register 'f'. If 'd'
is 0 the result is stored in the W regis-
ter. If 'd' is 1 the result is stored back in
register 'f'.
Description:
Description:
Words:
1
1
Words:
1
1
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write to
destination
Decode
Read
register
'f'
Process
data
Write to
destination
ADDWF
FSR,
0
ANDWF
FSR, 1
Example
Example
Before Instruction
Before Instruction
W
FSR =
=
0x17
0xC2
W
FSR =
=
0x17
0xC2
After Instruction
After Instruction
W
FSR =
=
0xD9
0xC2
W
FSR =
=
0x17
0x02
1997 Microchip Technology Inc.
DS30390E-page 149
PIC16C7X
BCF
Bit Clear f
BTFSC
Bit Test, Skip if Clear
Syntax:
Operands:
[label] BCF f,b
Syntax:
[label] BTFSC f,b
0 ≤ f ≤ 127
0 ≤ b ≤ 7
Operands:
0 ≤ f ≤ 127
0 ≤ b ≤ 7
Operation:
Status Affected:
Encoding:
0 → (f<b>)
Operation:
skip if (f<b>) = 0
None
None
Status Affected:
Encoding:
01
00bb
bfff
ffff
01
10bb
bfff
ffff
If bit 'b' in register 'f' is '1' then the next
instruction is executed.
If bit 'b', in register 'f', is '0' then the next
instruction is discarded, and a NOP is
executed instead, making this a 2TCY
instruction.
Description:
Words:
Bit 'b' in register 'f' is cleared.
Description:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write
register 'f'
Words:
1
Cycles:
1(2)
Q Cycle Activity:
Q1
Q2
Q3
Q4
BCF
FLAG_REG, 7
Example
Decode
Read
register 'f'
Process
data
No-
Operation
Before Instruction
FLAG_REG = 0xC7
If Skip:
(2nd Cycle)
After Instruction
FLAG_REG = 0x47
Q1
Q2
Q3
Q4
No-
No-
No-
No-
Operation Operation Operation Operation
HERE
FALSE
TRUE
BTFSC FLAG,1
Example
GOTO
PROCESS_CODE
•
•
•
Before Instruction
PC
=
address HERE
After Instruction
if FLAG<1> = 0,
BSF
Bit Set f
PC =
address TRUE
if FLAG<1>=1,
Syntax:
Operands:
[label] BSF f,b
PC =
address FALSE
0 ≤ f ≤ 127
0 ≤ b ≤ 7
Operation:
Status Affected:
Encoding:
1 → (f<b>)
None
01
01bb
bfff
ffff
Bit 'b' in register 'f' is set.
Description:
Words:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write
register 'f'
BSF
FLAG_REG,
7
Example
Before Instruction
FLAG_REG = 0x0A
After Instruction
FLAG_REG = 0x8A
DS30390E-page 150
1997 Microchip Technology Inc.
PIC16C7X
BTFSS
Bit Test f, Skip if Set
CALL
Call Subroutine
Syntax:
[label] BTFSS f,b
Syntax:
[ label ] CALL k
Operands:
0 ≤ f ≤ 127
0 ≤ b < 7
Operands:
Operation:
0 ≤ k ≤ 2047
(PC)+ 1→ TOS,
Operation:
skip if (f<b>) = 1
None
k → PC<10:0>,
(PCLATH<4:3>) → PC<12:11>
Status Affected:
Encoding:
Status Affected:
Encoding:
None
01
11bb
bfff
ffff
10
0kkk
kkkk
kkkk
If bit 'b' in register 'f' is '0' then the next
instruction is executed.
If bit 'b' is '1', then the next instruction is
discarded and a NOP is executed
instead, making this a 2TCY instruction.
Description:
Call Subroutine. First, return address
(PC+1) is pushed onto the stack. The
eleven bit immediate address is loaded
into PC bits <10:0>. The upper bits of
the PC are loaded from PCLATH. CALL
is a two cycle instruction.
Description:
Words:
1
Cycles:
1(2)
Words:
1
2
Q Cycle Activity:
Q1
Q2
Q3
Q4
Cycles:
Decode
Read
register 'f'
Process
data
No-
Operation
Q Cycle Activity:
1st Cycle
Q1
Q2
Q3
Q4
Decode
Read
Process
data
Write to
PC
If Skip:
(2nd Cycle)
literal 'k',
Push PC
to Stack
Q1
Q2
Q3
Q4
No-
No-
No-
No-
No-
No-
No-
No-
2nd Cycle
Example
Operation Operation Operation Operation
Operation Operation Operation Operation
HERE
FALSE
TRUE
BTFSC FLAG,1
GOTO
Example
HERE
CALL
THERE
PROCESS_CODE
Before Instruction
•
•
•
PC
=
Address HERE
After Instruction
PC
= Address THERE
Before Instruction
TOS = Address HERE+1
PC
=
address HERE
After Instruction
if FLAG<1> = 0,
PC =
address FALSE
if FLAG<1> = 1,
PC =
address TRUE
1997 Microchip Technology Inc.
DS30390E-page 151
PIC16C7X
CLRF
Clear f
CLRW
Clear W
Syntax:
[label] CLRF
0 ≤ f ≤ 127
f
Syntax:
[ label ] CLRW
None
Operands:
Operation:
Operands:
Operation:
00h → (f)
1 → Z
00h → (W)
1 → Z
Status Affected:
Encoding:
Z
Status Affected:
Encoding:
Z
00
0001
1fff
ffff
00
0001
0xxx
xxxx
The contents of register 'f' are cleared
and the Z bit is set.
Description:
W register is cleared. Zero bit (Z) is
set.
Description:
Words:
1
1
Words:
1
1
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write
register 'f'
Decode
No-
Operation
Process
data
Write to
W
CLRW
Example
CLRF
FLAG_REG
Example
Before Instruction
Before Instruction
FLAG_REG
After Instruction
W
=
0x5A
=
0x5A
After Instruction
W
=
0x00
1
FLAG_REG
Z
=
=
0x00
1
Z
=
CLRWDT
Syntax:
Clear Watchdog Timer
[ label ] CLRWDT
None
Operands:
Operation:
00h → WDT
0 → WDT prescaler,
1 → TO
1 → PD
Status Affected:
Encoding:
TO, PD
00
0000
0110
0100
CLRWDTinstruction resets the Watch-
dog Timer. It also resets the prescaler
of the WDT. Status bits TO and PD are
set.
Description:
Words:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No-
Operation
Process
data
Clear
WDT
Counter
CLRWDT
Example
Before Instruction
After Instruction
WDT counter
=
=
?
WDT counter
0x00
WDT prescaler=
0
1
1
TO
PD
=
=
DS30390E-page 152
1997 Microchip Technology Inc.
PIC16C7X
COMF
Complement f
[ label ] COMF f,d
0 ≤ f ≤ 127
DECFSZ
Syntax:
Decrement f, Skip if 0
Syntax:
Operands:
[ label ] DECFSZ f,d
Operands:
0 ≤ f ≤ 127
d
[0,1]
d
[0,1]
Operation:
(f) → (destination)
Operation:
(f) - 1 → (destination);
skip if result = 0
Status Affected:
Encoding:
Z
Status Affected:
Encoding:
None
00
1001
dfff
ffff
00
1011
dfff
ffff
The contents of register 'f' are comple-
mented. If 'd' is 0 the result is stored in
W. If 'd' is 1 the result is stored back in
register 'f'.
Description:
The contents of register 'f' are decre-
mented. If 'd' is 0 the result is placed in the
W register. If 'd' is 1 the result is placed
back in register 'f'.
If the result is 1, the next instruction, is
executed. If the result is 0, then a NOP is
executed instead making it a 2TCY instruc-
tion.
Description:
Words:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write to
destination
Words:
1
Cycles:
1(2)
Q Cycle Activity:
Q1
Q2
Q3
Q4
COMF
REG1,0
Example
Decode
Read
register 'f'
Process
data
Write to
destination
Before Instruction
REG1
After Instruction
REG1
=
0x13
If Skip:
(2nd Cycle)
Q1
Q2
Q3
Q4
=
=
0x13
0xEC
No-
No-
No-
No-
W
Operation Operation Operation Operation
DECF
Decrement f
[label] DECF f,d
0 ≤ f ≤ 127
HERE
DECFSZ
GOTO
CNT, 1
LOOP
Example
Syntax:
Operands:
CONTINUE •
•
•
d
[0,1]
Operation:
(f) - 1 → (destination)
Before Instruction
PC
=
address HERE
Status Affected:
Encoding:
Z
After Instruction
00
0011
dfff
ffff
CNT
if CNT =
PC
if CNT ≠
PC
=
CNT - 1
0,
address CONTINUE
0,
address HERE+1
Decrement register 'f'. If 'd' is 0 the
result is stored in the W register. If 'd' is
1 the result is stored back in register 'f'.
Description:
=
Words:
1
1
=
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write to
destination
DECF
CNT, 1
Example
Before Instruction
CNT
=
0x01
Z
=
0
After Instruction
CNT
Z
=
=
0x00
1
1997 Microchip Technology Inc.
DS30390E-page 153
PIC16C7X
GOTO
Unconditional Branch
INCF
Increment f
Syntax:
[ label ] GOTO k
Syntax:
Operands:
[ label ] INCF f,d
Operands:
Operation:
0 ≤ k ≤ 2047
0 ≤ f ≤ 127
d
[0,1]
k → PC<10:0>
PCLATH<4:3> → PC<12:11>
Operation:
(f) + 1 → (destination)
Status Affected:
Encoding:
None
Status Affected:
Encoding:
Z
10
1kkk
kkkk
kkkk
00
1010
dfff
ffff
GOTOis an unconditional branch. The
eleven bit immediate value is loaded
into PC bits <10:0>. The upper bits of
PC are loaded from PCLATH<4:3>.
GOTOis a two cycle instruction.
The contents of register 'f' are incre-
mented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
Description:
Description:
Words:
1
1
Words:
1
2
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
1st Cycle
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write to
destination
Decode
Read
literal 'k'
Process
data
Write to
PC
No-
No-
No-
No-
2nd Cycle
Operation Operation Operation Operation
INCF
CNT, 1
Example
GOTO THERE
Example
Before Instruction
CNT
Z
After Instruction
=
=
0xFF
0
After Instruction
PC
=
Address THERE
CNT
Z
=
=
0x00
1
DS30390E-page 154
1997 Microchip Technology Inc.
PIC16C7X
INCFSZ
Syntax:
Increment f, Skip if 0
[ label ] INCFSZ f,d
0 ≤ f ≤ 127
IORLW
Inclusive OR Literal with W
[ label ] IORLW k
0 ≤ k ≤ 255
Syntax:
Operands:
Operands:
Operation:
Status Affected:
Encoding:
Description:
d
[0,1]
(W) .OR. k → (W)
Z
Operation:
(f) + 1 → (destination),
skip if result = 0
11
1000
kkkk
kkkk
Status Affected:
Encoding:
None
The contents of the W register is
OR’ed with the eight bit literal 'k'. The
result is placed in the W register.
00
1111
dfff
ffff
The contents of register 'f' are incre-
mented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
If the result is 1, the next instruction is
executed. If the result is 0, a NOP is
executed instead making it a 2TCY
instruction.
Description:
Words:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal 'k'
Process
data
Write to
W
Words:
1
Cycles:
1(2)
IORLW
0x35
Example
Q Cycle Activity:
Q1
Q2
Q3
Q4
Before Instruction
Decode
Read
register 'f'
Process
data
Write to
destination
W
=
0x9A
After Instruction
W
Z
=
=
0xBF
1
If Skip:
(2nd Cycle)
Q1
Q2
Q3
Q4
No-
No-
No-
No-
Operation Operation Operation Operation
HERE
INCFSZ
GOTO
CNT, 1
LOOP
Example
CONTINUE •
•
•
Before Instruction
PC
=
address HERE
After Instruction
CNT
=
CNT + 1
if CNT=
0,
PC
if CNT≠
=
address CONTINUE
0,
PC
=
address HERE +1
1997 Microchip Technology Inc.
DS30390E-page 155
PIC16C7X
IORWF
Inclusive OR W with f
MOVLW
Move Literal to W
[ label ] MOVLW k
0 ≤ k ≤ 255
Syntax:
[ label ] IORWF f,d
Syntax:
Operands:
0 ≤ f ≤ 127
Operands:
Operation:
Status Affected:
Encoding:
Description:
d
[0,1]
k → (W)
Operation:
(W) .OR. (f) → (destination)
None
Status Affected:
Encoding:
Z
11
00xx
kkkk
kkkk
00
0100
dfff
ffff
The eight bit literal 'k' is loaded into W
register. The don’t cares will assemble
as 0’s.
Inclusive OR the W register with regis-
ter 'f'. If 'd' is 0 the result is placed in the
W register. If 'd' is 1 the result is placed
back in register 'f'.
Description:
Words:
1
1
Words:
1
1
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal 'k'
Process
data
Write to
W
Decode
Read
register
'f'
Process
data
Write to
destination
MOVLW
0x5A
Example
After Instruction
IORWF
RESULT, 0
Example
W
=
0x5A
Before Instruction
RESULT =
0x13
0x91
W
=
After Instruction
RESULT =
0x13
0x93
1
W
Z
=
=
MOVF
Move f
MOVWF
Move W to f
Syntax:
Operands:
[ label ] MOVF f,d
Syntax:
[ label ] MOVWF
0 ≤ f ≤ 127
(W) → (f)
f
0 ≤ f ≤ 127
Operands:
Operation:
Status Affected:
Encoding:
Description:
d
[0,1]
Operation:
(f) → (destination)
None
Status Affected:
Encoding:
Z
00
0000
1fff
ffff
00
1000
dfff
ffff
Move data from W register to register
'f'.
The contents of register f is moved to a
destination dependant upon the status
of d. If d = 0, destination is W register. If
d = 1, the destination is file register f
itself. d = 1 is useful to test a file regis-
ter since status flag Z is affected.
Description:
Words:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write
register 'f'
Words:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
MOVWF
OPTION_REG
Example
Decode
Read
register
'f'
Process
data
Write to
destination
Before Instruction
OPTION =
0xFF
0x4F
W
=
After Instruction
MOVF
FSR, 0
Example
OPTION =
0x4F
0x4F
After Instruction
W
=
W = value in FSR register
Z
= 1
DS30390E-page 156
1997 Microchip Technology Inc.
PIC16C7X
NOP
No Operation
[ label ] NOP
None
RETFIE
Return from Interrupt
Syntax:
Syntax:
[ label ] RETFIE
None
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Operands:
Operation:
No operation
None
TOS → PC,
1 → GIE
Status Affected:
Encoding:
None
00
0000
0xx0
0000
00
0000
0000
1001
No operation.
Return from Interrupt. Stack is POPed
and Top of Stack (TOS) is loaded in the
PC. Interrupts are enabled by setting
Global Interrupt Enable bit, GIE
(INTCON<7>). This is a two cycle
instruction.
Description:
1
1
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No-
No-
No-
Operation Operation Operation
Words:
1
2
Cycles:
NOP
Example
Q Cycle Activity:
1st Cycle
Q1
Q2
Q3
Q4
Decode
No-
Set the
Pop from
the Stack
Operation GIE bit
No-
No- No-
No-
2nd Cycle
Operation Operation Operation Operation
RETFIE
Example
After Interrupt
PC
GIE =
=
TOS
1
OPTION
Syntax:
Load Option Register
[ label ] OPTION
None
Operands:
Operation:
(W) → OPTION
Status Affected: None
00
0000
0110
0010
Encoding:
The contents of the W register are
loaded in the OPTION register. This
instruction is supported for code com-
patibility with PIC16C5X products.
Since OPTION is a readable/writable
register, the user can directly address
it.
Description:
Words:
Cycles:
Example
1
1
To maintain upward compatibility
with future PIC16CXX products, do
not use this instruction.
1997 Microchip Technology Inc.
DS30390E-page 157
PIC16C7X
RETLW
Return with Literal in W
RETURN
Return from Subroutine
[ label ] RETURN
None
Syntax:
[ label ] RETLW k
Syntax:
Operands:
Operation:
0 ≤ k ≤ 255
Operands:
Operation:
Status Affected:
Encoding:
Description:
k → (W);
TOS → PC
TOS → PC
None
Status Affected:
Encoding:
None
00
0000
0000
1000
11
01xx
kkkk
kkkk
Return from subroutine. The stack is
POPed and the top of the stack (TOS)
is loaded into the program counter.This
is a two cycle instruction.
The W register is loaded with the eight
bit literal 'k'. The program counter is
loaded from the top of the stack (the
return address). This is a two cycle
instruction.
Description:
Words:
1
2
Cycles:
Words:
1
2
Q Cycle Activity:
1st Cycle
Q1
Q2
Q3
Q4
Cycles:
Decode
No-
No-
Pop from
Q Cycle Activity:
1st Cycle
Q1
Q2
Q3
Q4
Operation Operation the Stack
Decode
Read
No-
WritetoW,
No-
No- No- No-
2nd Cycle
literal 'k' Operation Pop from
the Stack
Operation Operation Operation Operation
No-
No-
No-
No-
2nd Cycle
Example
RETURN
Example
Operation Operation Operation Operation
After Interrupt
PC
=
TOS
CALL TABLE ;W contains table
;offset value
•
;W now has table value
•
•
TABLE
ADDWF PC
RETLW k1
RETLW k2
•
;W = offset
;Begin table
;
•
•
RETLW kn
; End of table
Before Instruction
W
=
0x07
After Instruction
W
=
value of k8
DS30390E-page 158
1997 Microchip Technology Inc.
PIC16C7X
RLF
Rotate Left f through Carry
RRF
Rotate Right f through Carry
[ label ] RRF f,d
0 ≤ f ≤ 127
Syntax:
Operands:
[ label ]
RLF f,d
Syntax:
Operands:
0 ≤ f ≤ 127
d
[0,1]
d
[0,1]
Operation:
See description below
C
Operation:
See description below
C
Status Affected:
Encoding:
Status Affected:
Encoding:
00
1101
dfff
ffff
00
1100
dfff
ffff
The contents of register 'f' are rotated
one bit to the left through the Carry
Flag. If 'd' is 0 the result is placed in the
W register. If 'd' is 1 the result is stored
back in register 'f'.
The contents of register 'f' are rotated
one bit to the right through the Carry
Flag. If 'd' is 0 the result is placed in the
W register. If 'd' is 1 the result is placed
back in register 'f'.
Description:
Description:
C
Register f
C
Register f
Words:
1
1
Words:
1
1
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register
'f'
Process
data
Write to
destination
Decode
Read
register
'f'
Process
data
Write to
destination
RLF
REG1,0
Example
RRF
REG1,0
Example
Before Instruction
Before Instruction
REG1
C
=
=
1110 0110
0
REG1
C
=
=
1110 0110
0
After Instruction
After Instruction
REG1
W
C
=
=
=
1110 0110
1100 1100
1
REG1
W
C
=
=
=
1110 0110
0111 0011
0
1997 Microchip Technology Inc.
DS30390E-page 159
PIC16C7X
SLEEP
SUBLW
Subtract W from Literal
Syntax:
[ label ]
SUBLW k
Syntax:
[ label ] SLEEP
Operands:
Operation:
0 ≤ k ≤ 255
Operands:
Operation:
None
k - (W) → (W)
00h → WDT,
0 → WDT prescaler,
1 → TO,
Status Affected: C, DC, Z
Encoding:
11
110x
kkkk
kkkk
0 → PD
The W register is subtracted (2’s comple-
ment method) from the eight bit literal 'k'.
The result is placed in the W register.
Description:
Status Affected:
Encoding:
TO, PD
00
0000
0110
0011
Words:
1
1
The power-down status bit, PD is
cleared. Time-out status bit, TO is
set. Watchdog Timer and its pres-
caler are cleared.
Description:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
The processor is put into SLEEP
mode with the oscillator stopped. See
Section 14.8 for more details.
Decode
Read
literal 'k'
Process Write to W
data
Words:
1
1
Example 1:
SUBLW
0x02
Cycles:
Before Instruction
Q Cycle Activity:
Q1
Q2
Q3
Q4
W
C
Z
=
=
=
1
?
?
Decode
No-
No-
Go to
Operation Operation Sleep
After Instruction
Example:
SLEEP
W
C
Z
=
=
=
1
1; result is positive
0
Example 2:
Before Instruction
W
C
Z
=
=
=
2
?
?
After Instruction
W
C
Z
=
=
=
0
1; result is zero
1
Example 3:
Before Instruction
W
C
Z
=
=
=
3
?
?
After Instruction
W
C
Z
=
=
=
0xFF
0; result is negative
0
DS30390E-page 160
1997 Microchip Technology Inc.
PIC16C7X
SUBWF
Syntax:
Subtract W from f
SWAPF
Syntax:
Swap Nibbles in f
[ label ] SWAPF f,d
[ label ]
SUBWF f,d
Operands:
0 ≤ f ≤ 127
Operands:
0 ≤ f ≤ 127
d
[0,1]
d
[0,1]
Operation:
(f<3:0>) → (destination<7:4>),
(f<7:4>) → (destination<3:0>)
Operation:
(f) - (W) → (destination)
Status Affected: C, DC, Z
Status Affected:
Encoding:
None
Encoding:
00
0010
dfff
ffff
00
1110
dfff
ffff
Subtract (2’s complement method) W reg-
ister from register 'f'. If 'd' is 0 the result is
stored in the W register. If 'd' is 1 the
result is stored back in register 'f'.
Description:
The upper and lower nibbles of register
'f' are exchanged. If 'd' is 0 the result is
placed in W register. If 'd' is 1 the result
is placed in register 'f'.
Description:
Words:
1
1
Words:
1
1
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register 'f'
Process
data
Write to
destination
Decode
Read
register 'f'
Process
data
Write to
destination
Example 1:
SUBWF
REG1,1
SWAPF REG,
0
Example
Before Instruction
Before Instruction
REG1
REG1
=
=
=
=
3
2
?
?
W
C
Z
=
0xA5
After Instruction
REG1
W
=
=
0xA5
0x5A
After Instruction
REG1
=
1
2
W
C
Z
=
=
=
1; result is positive
0
Example 2:
Before Instruction
TRIS
Load TRIS Register
REG1
=
=
=
=
2
2
?
?
Syntax:
[label] TRIS
f
W
C
Z
Operands:
Operation:
5 ≤ f ≤ 7
(W) → TRIS register f;
Status Affected: None
After Instruction
00
Encoding:
0000 0110
0fff
REG1
=
0
W
C
Z
=
=
=
2
The instruction is supported for code
compatibility with the PIC16C5X prod-
ucts. Since TRIS registers are read-
able and writable, the user can directly
address them.
Description:
1; result is zero
1
Example 3:
Before Instruction
REG1
=
=
=
=
1
2
?
?
Words:
Cycles:
Example
1
1
W
C
Z
After Instruction
To maintain upward compatibility
with future PIC16CXX products, do
not use this instruction.
REG1
=
0xFF
2
0; result is negative
0
W
C
Z
=
=
=
1997 Microchip Technology Inc.
DS30390E-page 161
PIC16C7X
XORLW
Exclusive OR Literal with W
[label] XORLW k
XORWF
Syntax:
Exclusive OR W with f
[label] XORWF f,d
0 ≤ f ≤ 127
Syntax:
Operands:
Operands:
Operation:
Status Affected:
Encoding:
0 ≤ k ≤ 255
d
[0,1]
(W) .XOR. k → (W)
Operation:
(W) .XOR. (f) → (destination)
Z
Status Affected:
Encoding:
Z
11
1010 kkkk kkkk
00
0110
dfff
ffff
The contents of the W register are
XOR’ed with the eight bit literal 'k'.
The result is placed in the W regis-
ter.
Description:
Exclusive OR the contents of the W
register with register 'f'. If 'd' is 0 the
result is stored in the W register. If 'd' is
1 the result is stored back in register 'f'.
Description:
Words:
1
1
Words:
1
1
Cycles:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
Process Write to
literal 'k'
data
W
Decode
Read
register
'f'
Process
data
Write to
destination
Example:
XORLW 0xAF
Before Instruction
REG
1
Example
XORWF
W
=
0xB5
0x1A
Before Instruction
After Instruction
REG
W
=
=
0xAF
0xB5
W
=
After Instruction
REG
W
=
=
0x1A
0xB5
DS30390E-page 162
1997 Microchip Technology Inc.
PIC16C7X
16.3
ICEPIC: Low-cost PIC16CXXX
In-Circuit Emulator
16.0 DEVELOPMENT SUPPORT
16.1
Development Tools
ICEPIC is a low-cost in-circuit emulator solution for the
Microchip PIC16C5X and PIC16CXXX families of 8-bit
OTP microcontrollers.
The PIC16/17 microcontrollers are supported with a full
range of hardware and software development tools:
• PICMASTER/PICMASTER CE Real-Time
In-Circuit Emulator
ICEPIC is designed to operate on PC-compatible
machines ranging from 286-AT through Pentium
based machines under Windows 3.x environment.
ICEPIC features real time, non-intrusive emulation.
• ICEPIC Low-Cost PIC16C5X and PIC16CXXX
In-Circuit Emulator
• PRO MATE II Universal Programmer
16.4
PRO MATE II: Universal Programmer
• PICSTART Plus Entry-Level Prototype
Programmer
The PRO MATE II Universal Programmer is a full-fea-
tured programmer capable of operating in stand-alone
mode as well as PC-hosted mode.
• PICDEM-1 Low-Cost Demonstration Board
• PICDEM-2 Low-Cost Demonstration Board
• PICDEM-3 Low-Cost Demonstration Board
• MPASM Assembler
The PRO MATE II has programmable VDD and VPP
supplies which allows it to verify programmed memory
at VDD min and VDD max for maximum reliability. It has
an LCD display for displaying error messages, keys to
enter commands and a modular detachable socket
assembly to support various package types. In stand-
alone mode the PRO MATE II can read, verify or pro-
gram PIC16C5X, PIC16CXXX, PIC17CXX and
PIC14000 devices. It can also set configuration and
code-protect bits in this mode.
• MPLAB-SIM Software Simulator
• MPLAB-C (C Compiler)
• Fuzzy logic development system (fuzzyTECH −MP)
16.2
PICMASTER: High Performance
Universal In-Circuit Emulator with
MPLAB IDE
The PICMASTER Universal In-Circuit Emulator is
intended to provide the product development engineer
with a complete microcontroller design tool set for all
microcontrollers in the PIC12C5XX, PIC14C000,
PIC16C5X, PIC16CXXX and PIC17CXX families.
PICMASTER is supplied with the MPLAB Integrated
Development Environment (IDE), which allows editing,
“make” and download, and source debugging from a
single environment.
16.5
PICSTART Plus Entry Level
Development System
The PICSTART programmer is an easy-to-use, low-
cost prototype programmer. It connects to the PC via
one of the COM (RS-232) ports. MPLAB Integrated
Development Environment software makes using the
programmer simple and efficient. PICSTART Plus is
not recommended for production programming.
Interchangeable target probes allow the system to be
easily reconfigured for emulation of different proces-
sors. The universal architecture of the PICMASTER
allows expansion to support all new Microchip micro-
controllers.
PICSTART Plus supports all PIC12C5XX, PIC14000,
PIC16C5X, PIC16CXXX and PIC17CXX devices with
up to 40 pins. Larger pin count devices such as the
PIC16C923 and PIC16C924 may be supported with an
adapter socket.
The PICMASTER Emulator System has been
designed as
a real-time emulation system with
advanced features that are generally found on more
expensive development tools. The PC compatible 386
(and higher) machine platform and Microsoft Windows
3.x environment were chosen to best make these fea-
tures available to you, the end user.
A CE compliant version of PICMASTER is available for
European Union (EU) countries.
1997 Microchip Technology Inc.
DS30390E-page 163
PIC16C7X
an RS-232 interface, push-button switches, a potenti-
ometer for simulated analog input, a thermistor and
separate headers for connection to an external LCD
module and a keypad. Also provided on the PICDEM-3
board is an LCD panel, with 4 commons and 12 seg-
ments, that is capable of displaying time, temperature
and day of the week. The PICDEM-3 provides an addi-
tional RS-232 interface and Windows 3.1 software for
showing the demultiplexed LCD signals on a PC. A sim-
ple serial interface allows the user to construct a hard-
ware demultiplexer for the LCD signals.
16.6
PICDEM-1 Low-Cost PIC16/17
Demonstration Board
The PICDEM-1 is a simple board which demonstrates
the capabilities of several of Microchip’s microcontrol-
lers. The microcontrollers supported are: PIC16C5X
(PIC16C54 to PIC16C58A), PIC16C61, PIC16C62X,
PIC16C71, PIC16C8X, PIC17C42, PIC17C43 and
PIC17C44. All necessary hardware and software is
included to run basic demo programs. The users can
program the sample microcontrollers provided with
the PICDEM-1 board, on
a PRO MATE II or
16.9
MPLAB Integrated Development
Environment Software
PICSTART-16B programmer, and easily test firm-
ware. The user can also connect the PICDEM-1
board to the PICMASTER emulator and download
the firmware to the emulator for testing. Additional pro-
totype area is available for the user to build some addi-
tional hardware and connect it to the microcontroller
socket(s). Some of the features include an RS-232
interface, a potentiometer for simulated analog input,
push-button switches and eight LEDs connected to
PORTB.
The MPLAB IDE Software brings an ease of software
development previously unseen in the 8-bit microcon-
troller market. MPLAB is a windows based application
which contains:
• A full featured editor
• Three operating modes
- editor
- emulator
- simulator
• A project manager
• Customizable tool bar and key mapping
• A status bar with project information
• Extensive on-line help
16.7
PICDEM-2 Low-Cost PIC16CXX
Demonstration Board
The PICDEM-2 is a simple demonstration board that
supports the PIC16C62, PIC16C64, PIC16C65,
PIC16C73 and PIC16C74 microcontrollers. All the
necessary hardware and software is included to
run the basic demonstration programs. The user
can program the sample microcontrollers provided
with the PICDEM-2 board, on a PRO MATE II pro-
grammer or PICSTART-16C, and easily test firmware.
The PICMASTER emulator may also be used with the
PICDEM-2 board to test firmware. Additional prototype
area has been provided to the user for adding addi-
tional hardware and connecting it to the microcontroller
socket(s). Some of the features include a RS-232 inter-
face, push-button switches, a potentiometer for simu-
lated analog input, a Serial EEPROM to demonstrate
MPLAB allows you to:
• Edit your source files (either assembly or ‘C’)
• One touch assemble (or compile) and download
to PIC16/17 tools (automatically updates all
project information)
• Debug using:
- source files
- absolute listing file
• Transfer data dynamically via DDE (soon to be
replaced by OLE)
• Run up to four emulators on the same PC
The ability to use MPLAB with Microchip’s simulator
allows a consistent platform and the ability to easily
switch from the low cost simulator to the full featured
emulator with minimal retraining due to development
tools.
2
usage of the I C bus and separate headers for connec-
tion to an LCD module and a keypad.
16.8
PICDEM-3 Low-Cost PIC16CXXX
Demonstration Board
16.10 Assembler (MPASM)
The PICDEM-3 is a simple demonstration board that
supports the PIC16C923 and PIC16C924 in the PLCC
package. It will also support future 44-pin PLCC
microcontrollers with a LCD Module. All the neces-
sary hardware and software is included to run the
basic demonstration programs. The user can pro-
gram the sample microcontrollers provided with
the PICDEM-3 board, on a PRO MATE II program-
mer or PICSTART Plus with an adapter socket, and
easily test firmware. The PICMASTER emulator may
also be used with the PICDEM-3 board to test firm-
ware. Additional prototype area has been provided to
the user for adding hardware and connecting it to the
microcontroller socket(s). Some of the features include
The MPASM Universal Macro Assembler is a PC-
hosted symbolic assembler. It supports all microcon-
troller series including the PIC12C5XX, PIC14000,
PIC16C5X, PIC16CXXX, and PIC17CXX families.
MPASM offers full featured Macro capabilities, condi-
tional assembly, and several source and listing formats.
It generates various object code formats to support
Microchip's development tools as well as third party
programmers.
MPASM allows full symbolic debugging from
PICMASTER, Microchip’s Universal Emulator
System.
DS30390E-page 164
1997 Microchip Technology Inc.
PIC16C7X
MPASM has the following features to assist in develop-
ing software for specific use applications.
16.14 MP-DriveWay – Application Code
Generator
• Provides translation of Assembler source code to
object code for all Microchip microcontrollers.
MP-DriveWay is an easy-to-use Windows-based Appli-
cation Code Generator. With MP-DriveWay you can
visually configure all the peripherals in a PIC16/17
device and, with a click of the mouse, generate all the
initialization and many functional code modules in C
language. The output is fully compatible with Micro-
chip’s MPLAB-C C compiler. The code produced is
highly modular and allows easy integration of your own
code. MP-DriveWay is intelligent enough to maintain
your code through subsequent code generation.
• Macro assembly capability.
• Produces all the files (Object, Listing, Symbol,
and special) required for symbolic debug with
Microchip’s emulator systems.
• Supports Hex (default), Decimal and Octal source
and listing formats.
MPASM provides a rich directive language to support
programming of the PIC16/17. Directives are helpful in
making the development of your assemble source code
shorter and more maintainable.
16.15 SEEVAL Evaluation and
Programming System
16.11 Software Simulator (MPLAB-SIM)
The SEEVAL SEEPROM Designer’s Kit supports all
Microchip 2-wire and 3-wire Serial EEPROMs. The kit
includes everything necessary to read, write, erase or
program special features of any Microchip SEEPROM
product including Smart Serials and secure serials.
The Total Endurance Disk is included to aid in trade-
off analysis and reliability calculations. The total kit can
significantly reduce time-to-market and result in an
optimized system.
The MPLAB-SIM Software Simulator allows code
development in a PC host environment. It allows the
user to simulate the PIC16/17 series microcontrollers
on an instruction level. On any given instruction, the
user may examine or modify any of the data areas or
provide external stimulus to any of the pins. The input/
output radix can be set by the user and the execution
can be performed in; single step, execute until break, or
in a trace mode.
16.16 TrueGauge Intelligent Battery
Management
MPLAB-SIM fully supports symbolic debugging using
MPLAB-C and MPASM. The Software Simulator offers
the low cost flexibility to develop and debug code out-
side of the laboratory environment making it an excel-
lent multi-project software development tool.
The TrueGauge development tool supports system
development with the MTA11200B TrueGauge Intelli-
gent Battery Management IC. System design verifica-
tion can be accomplished before hardware prototypes
are built. User interface is graphically-oriented and
measured data can be saved in a file for exporting to
Microsoft Excel.
16.12 C Compiler (MPLAB-C)
The MPLAB-C Code Development System is a
complete ‘C’ compiler and integrated development
environment for Microchip’s PIC16/17 family of micro-
controllers. The compiler provides powerful integration
capabilities and ease of use not found with other
compilers.
16.17 KEELOQ Evaluation and
Programming Tools
KEELOQ evaluation and programming tools support
Microchips HCS Secure Data Products. The HCS eval-
uation kit includes an LCD display to show changing
codes, a decoder to decode transmissions, and a pro-
gramming interface to program test transmitters.
For easier source level debugging, the compiler pro-
vides symbol information that is compatible with the
MPLAB IDE memory display (PICMASTER emulator
software versions 1.13 and later).
16.13 Fuzzy Logic Development System
(fuzzyTECH-MP)
fuzzyTECH-MP fuzzy logic development tool is avail-
able in two versions - a low cost introductory version,
MP Explorer, for designers to gain a comprehensive
working knowledge of fuzzy logic system design; and a
full-featured version, fuzzyTECH-MP, edition for imple-
menting more complex systems.
Both versions include Microchip’s fuzzyLAB demon-
stration board for hands-on experience with fuzzy logic
systems implementation.
1997 Microchip Technology Inc.
DS30390E-page 165
PIC16C7X
TABLE 16-1: DEVELOPMENT TOOLS FROM MICROCHIP
ufzy
D e m o B o a r d s
E m u l a t o r P r o d u c t s
S o f t w a r e T o o l s
P r o g r a m m e r s
DS30390E-page 166
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
17.0 ELECTRICAL CHARACTERISTICS FOR PIC16C72
Absolute Maximum Ratings †
Ambient temperature under bias..................................................................................................................-55 to +125˚C
Storage temperature............................................................................................................................... -65˚C to +150˚C
Voltage on any pin with respect to VSS (except VDD, MCLR, and RA4) ..........................................-0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ............................................................................................................ -0.3 to +7.5V
Voltage on MCLR with respect to VSS (Note 2) ................................................................................................. 0 to +14V
Voltage on RA4 with respect to Vss................................................................................................................... 0 to +14V
Total power dissipation (Note 1).................................................................................................................................1.0W
Maximum current out of VSS pin ............................................................................................................................300 mA
Maximum current into VDD pin...............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD) .....................................................................................................................±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD)..............................................................................................................±20 mA
Maximum output current sunk by any I/O pin...........................................................................................................25 mA
Maximum output current sourced by any I/O pin .....................................................................................................25 mA
Maximum current sunk by PORTA and PORTB (combined)..................................................................................200 mA
Maximum current sourced by PORTA and PORTB (combined).............................................................................200 mA
Maximum current sunk by PORTC ........................................................................................................................200 mA
Maximum current sourced by PORTC ...................................................................................................................200 mA
Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - ∑ IOH} + ∑ {(VDD - VOH) x IOH} + ∑(VOl x IOL)
Note 2: Voltage spikes below VSS at the MCLR pin, inducing currents greater than 80 mA, may cause latch-up.Thus,
a series resistor of 50-100Ω should be used when applying a “low” level to the MCLRpin rather than pulling
this pin directly to VSS.
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
TABLE 17-1: CROSS REFERENCE OF DEVICE SPECS FOR OSCILLATOR CONFIGURATIONS
AND FREQUENCIES OF OPERATION (COMMERCIAL DEVICES)
OSC
PIC16C72-04
PIC16C72-10
PIC16C72-20
PIC16LC72-04
JW Devices
VDD: 4.0V to 6.0V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 2.5V to 6.0V
VDD: 4.0V to 6.0V
IDD: 5 mA max. at 5.5V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 3.8 mA max. at 3.0V IDD: 5 mA max. at 5.5V
RC
IPD: 5.0 µA max. at 3V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.0V to 6.0V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 2.5V to 6.0V
VDD: 4.0V to 6.0V
IDD: 5 mA max. at 5.5V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 3.8 mA max. at 3.0V IDD: 5 mA max. at 5.5V
XT
HS
IPD: 5.0 µA max. at 3V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
IDD: 13.5 mA typ. at 5.5V IDD: 10 mA max. at 5.5V IDD: 20 mA max. at 5.5V
IDD: 20 mA max. at 5.5V
IPD: 1.5 µA typ. at 4.5V
Freq: 20 MHz max.
Not recommended for use
in HS mode
IPD: 1.5 µA typ. at 4.5V
IPD: 1.5 µA typ. at 4.5V
IPD: 1.5 µA typ. at 4.5V
Freq: 4 MHz max.
Freq: 10 MHz max.
Freq: 20 MHz max.
VDD: 4.0V to 6.0V
IDD: 52.5 µA typ. at
32 kHz, 4.0V
IPD: 0.9 µA typ. at 4.0V
Freq: 200 kHz max.
VDD: 2.5V to 6.0V
IDD: 48 µA max. at
32 kHz, 3.0V
IPD: 5.0 µA max. at 3.0V IPD: 5.0 µA max. at 3.0V
Freq: 200 kHz max.
VDD: 2.5V to 6.0V
IDD: 48 µA max. at
32 kHz, 3.0V
Not recommended for use Not recommended for use
in LP mode in LP mode
LP
Freq: 200 kHz max.
The shaded sections indicate oscillator selections which are tested for functionality, but not for MIN/MAX specifications.
It is recommended that the user select the device type that ensures the specifications required.
1997 Microchip Technology Inc.
DS30390E-page 167
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
17.1
DC Characteristics:
PIC16C72-04 (Commercial, Industrial, Extended)
PIC16C72-10 (Commercial, Industrial, Extended)
PIC16C72-20 (Commercial, Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40˚C ≤ TA ≤ +125˚C for extended,
DC CHARACTERISTICS
-40˚C
0˚C
≤ TA ≤ +85˚C for industrial and
≤ TA ≤ +70˚C for commercial
Param
No.
Characteristic
Sym
VDD
Min Typ† Max Units
Conditions
D001
D001A
Supply Voltage
4.0
4.5
-
-
6.0
5.5
V
V
XT, RC and LP osc configuration
HS osc configuration
D002*
D003
RAM Data Retention
Voltage (Note 1)
VDR
-
1.5
-
V
VDD start voltage to
ensure internal Power-
on Reset Signal
VPOR
-
VSS
-
V
See section on Power-on Reset for details
D004*
VDD rise rate to ensure
internal Power-on Reset
Signal
SVDD
0.05
-
-
V/ms See section on Power-on Reset for details
D005
D010
Brown-out Reset Voltage BVDD
3.7
3.7
-
4.0 4.3
4.0 4.4
V
V
BODEN bit in configuration word enabled
Extended Only
Supply Current
(Note 2,5)
IDD
2.7 5.0 mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 5.5V (Note 4)
D013
D015
-
-
10
20
mA HS osc configuration
FOSC = 20 MHz, VDD = 5.5V
Brown-out Reset Current ∆IBOR
350 425 µA BOR enabled VDD = 5.0V
(Note 6)
D020
D021
D021A
D021B
Power-down Current
(Note 3,5)
IPD
-
-
-
-
10.5 42 µA VDD = 4.0V, WDT enabled, -40°C to +85°C
1.5
1.5
2.5
16
19
19
µA VDD = 4.0V, WDT disabled, -0°C to +70°C
µA VDD = 4.0V, WDT disabled, -40°C to +85°C
µA VDD = 4.0V, WDT disabled, -40°C to +125°C
D023
Brown-out Reset Current ∆IBOR
-
350 425 µA BOR enabled VDD = 5.0V
(Note 6)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
6: The ∆ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
DS30390E-page 168
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
17.2
DC Characteristics: PIC16LC72-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40˚C
0˚C
≤ TA ≤ +85˚C for industrial and
≤ TA ≤ +70˚C for commercial
DC CHARACTERISTICS
Param
No.
Characteristic
Sym Min Typ† Max Units
Conditions
D001
Supply Voltage
VDD
2.5
-
-
6.0
-
V
V
LP, XT, RC osc configuration (DC - 4 MHz)
See section on Power-on Reset for details
D002* RAM Data Retention Volt- VDR
age (Note 1)
1.5
D003
VDD start voltage to
ensure internal Power-on
Reset signal
VPOR
-
VSS
-
-
-
V
D004* VDD rise rate to ensure
internal Power-on Reset
signal
SVDD
0.05
V/ms See section on Power-on Reset for details
D005
D010
Brown-out Reset Voltage BVDD
3.7
-
4.0
2.0
4.3
3.8
V
BODEN bit in configuration word enabled
Supply Current
(Note 2,5)
IDD
mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 3.0V (Note 4)
D010A
-
-
22.5 48
350 425
µA LP osc configuration
FOSC = 32 kHz, VDD = 3.0V, WDT disabled
D015* Brown-out Reset Current ∆IBOR
µA BOR enabled VDD = 5.0V
(Note 6)
D020
D021
D021A
Power-down Current
(Note 3,5)
IPD
-
-
-
7.5
0.9
0.9
30
5
5
µA VDD = 3.0V, WDT enabled, -40°C to +85°C
µA VDD = 3.0V, WDT disabled, 0°C to +70°C
µA VDD = 3.0V, WDT disabled, -40°C to +85°C
D023* Brown-out Reset Current ∆IBOR
-
350 425
µA BOR enabled VDD = 5.0V
(Note 6)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
6: The ∆ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
1997 Microchip Technology Inc.
DS30390E-page 169
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
17.3
DC Characteristics:
PIC16C72-04 (Commercial, Industrial, Extended)
PIC16C72-10 (Commercial, Industrial, Extended)
PIC16C72-20 (Commercial, Industrial, Extended)
PIC16LC72-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +125˚C for extended,
-40˚C ≤ TA ≤ +85˚C for industrial and
DC CHARACTERISTICS
0˚C
≤ TA ≤ +70˚C for commercial
Operating voltage VDD range as described in DC spec Section 17.1
and Section 17.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Input Low Voltage
I/O ports
VIL
D030
with TTL buffer
VSS
VSS
VSS
VSS
VSS
-
-
-
-
-
0.15VDD
0.8V
0.2VDD
0.2VDD
0.3VDD
V
V
V
V
V
For entire VDD range
4.5 ≤ VDD ≤ 5.5V
D030A
D031
D032
D033
with Schmitt Trigger buffer
MCLR, OSC1 (in RC mode)
OSC1 (in XT, HS and LP)
Input High Voltage
I/O ports
Note1
VIH
-
-
-
D040
D040A
with TTL buffer
2.0
0.25VDD
+ 0.8V
VDD
VDD
V
V
4.5 ≤ VDD ≤ 5.5V
For entire VDD range
D041
D042
D042A
D043
D070
with Schmitt Trigger buffer
MCLR
0.8VDD
0.8VDD
0.7VDD
0.9VDD
50
-
-
-
-
VDD
VDD
VDD
VDD
V
V
V
V
For entire VDD range
Note1
OSC1 (XT, HS and LP)
OSC1 (in RC mode)
PORTB weak pull-up current
Input Leakage Current (Notes 2, 3)
I/O ports
IPURB
IIL
250 †400
µA VDD = 5V, VPIN = VSS
D060
-
-
±1
µA Vss ≤ VPIN ≤ VDD, Pin at hi-
impedance
D061
D063
MCLR, RA4/T0CKI
OSC1
-
-
-
-
±5
±5
µA Vss ≤ VPIN ≤ VDD
µA Vss ≤ VPIN ≤ VDD, XT, HS and
LP osc configuration
Output Low Voltage
D080
I/O ports
VOL
-
-
-
-
-
-
-
-
0.6
0.6
0.6
0.6
V
V
V
V
IOL = 8.5 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 7.0 mA, VDD = 4.5V,
-40°C to +125°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.2 mA, VDD = 4.5V,
-40°C to +125°C
D080A
D083
OSC2/CLKOUT (RC osc config)
D083A
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR/VPP pin is strongly dependent on the applied voltage level. The specified
levels represent normal operating conditions. Higher leakage current may be measured at different input volt-
ages.
3: Negative current is defined as current sourced by the pin.
DS30390E-page 170
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +125˚C for extended,
-40˚C ≤ TA ≤ +85˚C for industrial and
DC CHARACTERISTICS
0˚C
≤ TA ≤ +70˚C for commercial
Operating voltage VDD range as described in DC spec Section 17.1
and Section 17.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Output High Voltage
D090
I/O ports (Note 3)
VOH VDD - 0.7 -
VDD - 0.7 -
-
-
V
V
V
V
V
IOH = -3.0 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -2.5 mA, VDD = 4.5V,
-40°C to +125°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.0 mA, VDD = 4.5V,
-40°C to +125°C
D090A
D092
OSC2/CLKOUT (RC osc config)
VDD - 0.7 -
-
D092A
D150*
VDD - 0.7 -
-
Open-Drain High Voltage
Capacitive Loading Specs on Out-
put Pins
VOD
-
-
-
-
14
RA4 pin
D100
OSC2 pin
COSC2
15
pF In XT, HS and LP modes
when external clock is used to
drive OSC1.
D101
D102
All I/O pins and OSC2 (in RC mode) CIO
-
-
-
-
50
400
pF
pF
2
CB
SCL, SDA in I C mode
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR/VPP pin is strongly dependent on the applied voltage level. The specified
levels represent normal operating conditions. Higher leakage current may be measured at different input volt-
ages.
3: Negative current is defined as current sourced by the pin.
1997 Microchip Technology Inc.
DS30390E-page 171
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
17.4
Timing Parameter Symbology
The timing parameter symbols have been created following one of the following formats:
2
1. TppS2ppS
2. TppS
3. TCC:ST
4. Ts
(I C specifications only)
2
(I C specifications only)
T
F
Frequency
T
Time
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
CLKOUT
CS
osc
rd
OSC1
RD
ck
cs
di
rw
sc
ss
t0
RD or WR
SCK
SDI
do
dt
SDO
SS
Data in
I/O port
MCLR
T0CKI
T1CKI
WR
io
t1
mc
wr
Uppercase letters and their meanings:
S
F
H
I
Fall
P
R
V
Z
Period
High
Rise
Invalid (Hi-impedance)
Low
Valid
L
Hi-impedance
2
I C only
AA
output access
Bus free
High
Low
High
Low
BUF
2
TCC:ST (I C specifications only)
CC
HD
ST
DAT
STA
Hold
SU
Setup
DATA input hold
START condition
STO
STOP condition
FIGURE 17-1: LOAD CONDITIONS
Load condition 1
Load condition 2
VDD/2
RL
CL
CL
Pin
Pin
VSS
VSS
RL = 464Ω
CL = 50 pF for all pins except OSC2
15 pF for OSC2 output
DS30390E-page 172
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
17.5
Timing Diagrams and Specifications
FIGURE 17-2: EXTERNAL CLOCK TIMING
Q4
Q1
1
Q2
Q3
Q4
4
Q1
OSC1
3
3
4
2
CLKOUT
TABLE 17-2: EXTERNAL CLOCK TIMING REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units Conditions
Fosc External CLKIN Frequency
DC
DC
DC
DC
DC
DC
0.1
—
—
—
—
—
—
—
4
4
MHz XT and RC osc mode
MHz HS osc mode (-04)
MHz HS osc mode (-10)
MHz HS osc mode (-20)
kHz LP osc mode
(Note 1)
10
20
200
4
Oscillator Frequency
(Note 1)
MHz RC osc mode
4
MHz XT osc mode
4
5
—
—
20
200
MHz HS osc mode
kHz LP osc mode
1
Tosc External CLKIN Period
250
250
100
50
—
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
µs
ns
ns
ns
XT and RC osc mode
HS osc mode (-04)
HS osc mode (-10)
HS osc mode (-20)
LP osc mode
(Note 1)
—
—
5
—
Oscillator Period
(Note 1)
250
250
250
—
RC osc mode
10,000
250
XT osc mode
HS osc mode (-04)
100
50
—
—
250
250
ns
ns
HS osc mode (-10)
HS osc mode (-20)
5
—
—
—
—
—
—
—
—
—
DC
—
µs
ns
ns
µs
ns
ns
ns
ns
LP osc mode
TCY = 4/FOSC
XT oscillator
LP oscillator
HS oscillator
XT oscillator
LP oscillator
HS oscillator
2
3
TCY
Instruction Cycle Time (Note 1)
200
100
2.5
15
TosL, External Clock in (OSC1) High or
TosH Low Time
—
—
4
TosR, External Clock in (OSC1) Rise or
TosF Fall Time
—
25
50
15
—
—
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are based on
characterization data for that particular oscillator type under standard operating conditions with the device executing code.
Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current con-
sumption. All devices are tested to operate at "min." values with an external clock applied to the OSC1/CLKIN pin.
When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices.
1997 Microchip Technology Inc.
DS30390E-page 173
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 17-3: CLKOUT AND I/O TIMING
Q1
Q2
Q3
Q4
OSC1
11
10
CLKOUT
13
14
12
18
19
16
I/O Pin
(input)
15
17
I/O Pin
new value
old value
(output)
20, 21
Note: Refer to Figure 17-1 for load conditions.
TABLE 17-3: CLKOUT AND I/O TIMING REQUIREMENTS
Parameter Sym
No.
Characteristic
Min
Typ†
Max
Units Conditions
10*
11*
12*
13*
14*
15*
16*
17*
TosH2ckL OSC1↑ to CLKOUT↓
TosH2ckH OSC1↑ to CLKOUT↑
—
—
—
—
—
75
75
35
35
—
—
—
50
200
200
ns
ns
ns
ns
ns
ns
ns
ns
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
TckR
TckF
CLKOUT rise time
CLKOUT fall time
100
100
TckL2ioV CLKOUT ↓ to Port out valid
TioV2ckH Port in valid before CLKOUT ↑
0.5TCY + 20
—
TOSC + 200
TckH2ioI
Port in hold after CLKOUT ↑
0
—
TosH2ioV OSC1↑ (Q1 cycle) to
—
150
Port out valid
18*
TosH2ioI
OSC1↑ (Q2 cycle) to
Port input invalid (I/O in
hold time)
PIC16C72
100
200
—
—
—
—
ns
ns
PIC16LC72
19*
20*
TioV2osH Port input valid to OSC1↑ (I/O in setup time)
0
—
—
10
—
10
—
—
—
—
40
80
40
80
—
—
ns
ns
ns
ns
ns
ns
ns
TioR
Port output rise time
Port output fall time
INT pin high or low time
PIC16C72
PIC16LC72
PIC16C72
PIC16LC72
—
21*
TioF
—
—
22††*
23††*
Tinp
Trbp
TCY
TCY
RB7:RB4 change INT high or low time
* These parameters are characterized but not tested.
†Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance
only and are not tested.
†† These parameters are asynchronous events not related to any internal clock edges.
Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC.
DS30390E-page 174
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 17-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Time-out
Internal
RESET
Watchdog
Timer
RESET
31
34
34
I/O Pins
Note: Refer to Figure 17-1 for load conditions.
FIGURE 17-5: BROWN-OUT RESET TIMING
BVDD
VDD
35
TABLE 17-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER,
AND BROWN-OUT RESET REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max Units
Conditions
30
TmcL MCLR Pulse Width (low)
2
7
—
—
µs VDD = 5V, -40˚C to +125˚C
31*
Twdt
Watchdog Timer Time-out Period
18
33
ms VDD = 5V, -40˚C to +125˚C
(No Prescaler)
32
33*
34
Tost
Oscillation Start-up Timer Period
—
28
—
1024TOSC
—
—
TOSC = OSC1 period
Tpwrt Power-up Timer Period
72
—
132
2.1
ms VDD = 5V, -40˚C to +125˚C
TIOZ
I/O Hi-impedance from MCLR Low
µs
or Watchdog Timer Reset
35
TBOR
Brown-out Reset pulse width
100
—
—
µs
VDD ≤ BVDD (D005)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 175
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 17-6: TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
RA4/T0CKI
41
40
42
RC0/T1OSO/T1CKI
46
45
47
48
TMR0 or
TMR1
Note: Refer to Figure 17-1 for load conditions.
TABLE 17-5: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Sym
Characteristic
Min
Typ† Max Units Conditions
40*
Tt0H
T0CKI High Pulse Width
No Prescaler
0.5TCY + 20
—
—
ns Must also meet
parameter 42
With Prescaler
No Prescaler
10
0.5TCY + 20
10
—
—
—
—
—
—
—
—
—
—
ns
41*
42*
Tt0L
Tt0P
T0CKI Low Pulse Width
T0CKI Period
ns Must also meet
parameter 42
With Prescaler
No Prescaler
With Prescaler
ns
ns
TCY + 40
Greater of:
20 or TCY + 40
ns N = prescale value
(2, 4, ..., 256)
N
0.5TCY + 20
15
45*
46*
47*
Tt1H
Tt1L
Tt1P
T1CKI High Time Synchronous, Prescaler = 1
—
—
—
—
—
—
ns Must also meet
parameter 47
Synchronous, PIC16C7X
ns
ns
Prescaler =
2,4,8
PIC16LC7X
25
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
—
—
—
—
ns
ns
50
T1CKI Low Time
Synchronous, Prescaler = 1
Synchronous, PIC16C7X
0.5TCY + 20
ns Must also meet
parameter 47
15
25
ns
ns
Prescaler =
2,4,8
PIC16LC7X
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
ns
ns
50
T1CKI input period Synchronous PIC16C7X
Greater of:
30 OR TCY + 40
ns N = prescale value
(1, 2, 4, 8)
N
Greater of:
50 OR TCY + 40
N = prescale value
(1, 2, 4, 8)
PIC16LC7X
N
60
Asynchronous PIC16C7X
PIC16LC7X
—
—
—
—
—
ns
ns
100
DC
Ft1
Timer1 oscillator input frequency range
(oscillator enabled by setting bit T1OSCEN)
200
kHz
48
*
TCKEZtmr1 Delay from external clock edge to timer increment
2Tosc
—
7Tosc
—
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 176
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 17-7: CAPTURE/COMPARE/PWM TIMINGS (CCP1)
RC2/CCP1
(Capture Mode)
50
51
52
RC2/CCP1
(Compare or PWM Mode)
53
54
Note: Refer to Figure 17-1 for load conditions.
TABLE 17-6: CAPTURE/COMPARE/PWM REQUIREMENTS (CCP1)
Param Sym Characteristic
No.
Min
Typ† Max Units Conditions
50*
TccL CCP1 input low time
No Prescaler
0.5TCY + 20
—
—
—
—
—
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
ns
ns
With Prescaler PIC16C72
PIC16LC72
10
20
51*
TccH
TccP
No Prescaler
0.5TCY + 20
CCP1 input high time
CCP1 input period
With Prescaler PIC16C72
PIC16LC72
10
20
52*
53*
3TCY + 40
N
ns N = prescale
value (1,4 or 16)
TccR CCP1 output rise time
TccF CCP1 output fall time
PIC16C72
PIC16LC72
PIC16C72
PIC16LC72
—
—
—
—
10
25
10
25
25
45
25
45
ns
ns
ns
ns
54*
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 177
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 17-8: SPI MODE TIMING
SS
70
SCK
(CKP = 0)
71
72
78
79
79
78
SCK
(CKP = 1)
80
SDO
SDI
77
75, 76
74
73
Note: Refer to Figure 17-1 for load conditions
TABLE 17-7: SPI MODE REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max
Units
Conditions
70
TssL2scH,
TssL2scL
SS↓ to SCK↓ or SCK↑ input
TCY
—
—
ns
71
72
73
TscH
TscL
SCK input high time (slave mode)
SCK input low time (slave mode)
TCY + 20
TCY + 20
50
—
—
—
—
—
—
ns
ns
ns
TdiV2scH,
TdiV2scL
Setup time of SDI data input to SCK
edge
74
TscH2diL,
TscL2diL
Hold time of SDI data input to SCK
edge
50
—
—
ns
75
76
77
78
79
80
TdoR
SDO data output rise time
—
—
10
—
—
—
10
10
—
10
10
—
25
25
50
25
25
50
ns
ns
ns
ns
ns
ns
TdoF
SDO data output fall time
TssH2doZ
TscR
SS↑ to SDO output hi-impedance
SCK output rise time (master mode)
SCK output fall time (master mode)
TscF
TscH2doV,
TscL2doV
SDO data output valid after SCK
edge
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 178
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 17-9: I C BUS START/STOP BITS TIMING
SCL
93
91
90
92
SDA
STOP
Condition
START
Condition
Note: Refer to Figure 17-1 for load conditions
2
TABLE 17-8: I C BUS START/STOP BITS REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min Typ Max Units
Conditions
90
91
92
93
TSU:STA START condition
Setup time
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
4700
600
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Only relevant for repeated START
condition
ns
ns
ns
ns
THD:STA START condition
Hold time
4000
600
After this period the first clock
pulse is generated
TSU:STO STOP condition
Setup time
4700
600
THD:STO STOP condition
Hold time
4000
600
1997 Microchip Technology Inc.
DS30390E-page 179
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 17-10: I C BUS DATA TIMING
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
Note: Refer to Figure 17-1 for load conditions
2
TABLE 17-9: I C BUS DATA REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Max
Units
Conditions
100
THIGH
Clock high time
100 kHz mode
400 kHz mode
4.0
0.6
—
—
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
4.7
—
—
101
TLOW
Clock low time
100 kHz mode
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
400 kHz mode
1.3
—
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
—
—
102
103
TR
TF
SDA and SCL rise
time
100 kHz mode
400 kHz mode
1000
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
SDA and SCL fall time 100 kHz mode
400 kHz mode
—
300
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
90
91
TSU:STA START condition
setup time
100 kHz mode
400 kHz mode
4.7
0.6
4.0
0.6
0
—
—
µs
µs
µs
µs
ns
µs
ns
ns
µs
µs
ns
ns
µs
µs
Only relevant for repeated
START condition
THD:STA START condition hold 100 kHz mode
—
After this period the first clock
pulse is generated
time
400 kHz mode
100 kHz mode
400 kHz mode
—
106
107
92
THD:DAT Data input hold time
—
0
0.9
—
TSU:DAT Data input setup time 100 kHz mode
400 kHz mode
250
100
4.7
0.6
—
Note 2
—
TSU:STO STOP condition setup 100 kHz mode
—
time
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
—
109
110
TAA
Output valid from
clock
3500
—
Note 1
—
TBUF
Bus free time
4.7
1.3
—
Time the bus must be free
before a new transmission can
start
—
Cb
Bus capacitive loading
—
400
pF
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of
the falling edge of SCL to avoid unintended generation of START or STOP conditions.
2
2
2: A fast-mode (400 kHz) I C-bus device can be used in a standard-mode (100 kHz)S I C-bus system, but the requirement
tsu;DAT ≥ 250 ns must then be met.This will automatically be the case if the device does not stretch the LOW period of the
SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line
2
TR max.+tsu;DAT = 1000 + 250 = 1250 ns (according to the standard-mode I C bus specification) before the SCL line is
released.
DS30390E-page 180
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
TABLE 17-10: A/D CONVERTER CHARACTERISTICS:
PIC16C72-04 (Commercial, Industrial, Extended)
PIC16C72-10 (Commercial, Industrial, Extended)
PIC16C72-20 (Commercial, Industrial, Extended)
PIC16LC72-04 (Commercial, Industrial)
Param Sym Characteristic
No.
Min
Typ†
Max
Units
Conditions
A01
NR Resolution
—
—
—
—
—
—
—
—
—
—
—
—
8-bits
bit VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A02 EABS Total Absolute error
< ± 1
< ± 1
< ± 1
< ± 1
< ± 1
LSb
LSb
LSb
LSb
LSb
A03
A04
A05
EIL Integral linearity error
EDL Differential linearity error
EFS Full scale error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A06 EOFF Offset error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A10
—
Monotonicity
—
3.0V
guaranteed
—
—
V
VSS ≤ VAIN ≤ VREF
A20 VREF Reference voltage
—
—
—
VDD + 0.3
VREF + 0.3
10.0
A25
A30
VAIN Analog input voltage
VSS - 0.3
—
V
ZAIN Recommended impedance of
analog voltage source
kΩ
A40
A50
IAD A/D conversion current (VDD) PIC16C72
PIC16LC72
—
—
180
90
—
—
µA Average current consump-
tion when A/D is on.
(Note 1)
µA
IREF VREF input current (Note 2)
10
—
1000
µA During VAIN acquisition.
Based on differential of
VHOLD to VAIN to charge
CHOLD, see Section 13.1.
—
—
10
µA During A/D Conversion
cycle
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: When A/D is off, it will not consume any current other than minor leakage current.
The power-down current spec includes any such leakage from the A/D module.
2: VREF current is from RA3 pin or VDD pin, whichever is selected as reference input.
1997 Microchip Technology Inc.
DS30390E-page 181
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 17-11: A/D CONVERSION TIMING
BSF ADCON0, GO
1 TCY
(TOSC/2) (1)
134
131
130
Q4
132
A/D CLK
7
6
5
4
3
2
1
0
A/D DATA
NEW_DATA
DONE
OLD_DATA
ADRES
ADIF
GO
SAMPLING STOPPED
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the
SLEEPinstruction to be executed.
TABLE 17-11: A/D CONVERSION REQUIREMENTS
Param Sym Characteristic
No.
Min
Typ†
Max
Units
Conditions
130
TAD A/D clock period
PIC16C72
PIC16LC72
PIC16C72
PIC16LC72
1.6
2.0
2.0
3.0
—
—
—
—
—
µs
TOSC based, VREF ≥ 3.0V
µs TOSC based, VREF full range
µs A/D RC Mode
µs A/D RC Mode
TAD
4.0
6.0
9.5
6.0
9.0
—
131
132
TCNV Conversion time (not including S/H
time) (Note 1)
TACQ Acquisition time
Note 2
5*
20
—
—
—
µs
µs The minimum time is the amplifier
settling time. This may be used if
the "new" input voltage has not
changed by more than 1 LSb (i.e.,
20.0 mV @ 5.12V) from the last
sampled voltage (as stated on
CHOLD).
134
135
TGO Q4 to A/D clock start
—
TOSC/2 §
—
—
—
If the A/D clock source is selected
as RC, a time of TCY is added
before the A/D clock starts. This
allows the SLEEPinstruction to be
executed.
TSWC Switching from convert → sample time
1.5 §
—
TAD
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
§
This specification ensured by design.
Note 1: ADRES register may be read on the following TCY cycle.
2: See Section 13.1 for min conditions.
DS30390E-page 182
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
18.0 ELECTRICAL CHARACTERISTICS FOR PIC16C73/74
Absolute Maximum Ratings †
Ambient temperature under bias..................................................................................................................-55 to +125˚C
Storage temperature............................................................................................................................... -65˚C to +150˚C
Voltage on any pin with respect to VSS (except VDD, MCLR. and RA4)...........................................-0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ............................................................................................................ -0.3 to +7.5V
Voltage on MCLR with respect to VSS (Note 2) ................................................................................................. 0 to +14V
Voltage on RA4 with respect to Vss................................................................................................................... 0 to +14V
Total power dissipation (Note 1).................................................................................................................................1.0W
Maximum current out of VSS pin ............................................................................................................................300 mA
Maximum current into VDD pin...............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD) .....................................................................................................................±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD)..............................................................................................................±20 mA
Maximum output current sunk by any I/O pin...........................................................................................................25 mA
Maximum output current sourced by any I/O pin .....................................................................................................25 mA
Maximum current sunk by PORTA, PORTB, and PORTE (combined) (Note 3).....................................................200 mA
Maximum current sourced by PORTA, PORTB, and PORTE (combined) (Note 3) ...............................................200 mA
Maximum current sunk by PORTC and PORTD (combined) (Note 3)...................................................................200 mA
Maximum current sourced by PORTC and PORTD (combined) (Note 3)..............................................................200 mA
Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - ∑ IOH} + ∑ {(VDD - VOH) x IOH} + ∑(VOl x IOL)
Note 2: Voltage spikes below VSS at the MCLR pin, inducing currents greater than 80 mA, may cause latch-up.Thus,
a series resistor of 50-100Ω should be used when applying a “low” level to the MCLRpin rather than pulling
this pin directly to VSS.
Note 3: PORTD and PORTE are not implemented on the PIC16C73.
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
TABLE 18-1: CROSS REFERENCE OF DEVICE SPECS FOR OSCILLATOR CONFIGURATIONS
AND FREQUENCIES OF OPERATION (COMMERCIAL DEVICES)
PIC16C73-04
PIC16C74-04
PIC16C73-10
PIC16C74-10
PIC16C73-20
PIC16C74-20
PIC16LC73-04
PIC16LC74-04
OSC
JW Devices
VDD: 4.0V to 6.0V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 3.0V to 6.0V
VDD: 4.0V to 6.0V
IDD: 5 mA max. at 5.5V
IPD: 21 µA max. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V IDD: 2.7 mA typ. at 5.5V IDD: 3.8 mA max. at 3.0V IDD: 5 mA max. at 5.5V
RC
IPD: 1.5 µA typ. at 4V
IPD: 1.5 µA typ. at 4V
IPD: 13.5 µA max. at 3V
IPD: 21 µA max. at 4V
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.0V to 6.0V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 3.0V to 6.0V
VDD: 4.0V to 6.0V
IDD: 5 mA max. at 5.5V
IPD: 21 µA max. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V IDD: 2.7 mA typ. at 5.5V IDD: 3.8 mA max. at 3.0V IDD: 5 mA max. at 5.5V
XT
HS
IPD: 1.5 µA typ. at 4V
IPD: 1.5 µA typ. at 4V
IPD: 13.5 µA max. at 3V
IPD: 21 µA max. at 4V
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
IDD: 13.5 mA typ. at 5.5V IDD: 15 mA max. at 5.5V IDD: 30 mA max. at 5.5V
IDD: 30 mA max. at 5.5V
IPD: 1.5 µA typ. at 4.5V
Freq: 20 MHz max.
Not recommended for
use in HS mode
IPD: 1.5 µA typ. at 4.5V
IPD: 1.5 µA typ. at 4.5V
IPD: 1.5 µA typ. at 4.5V
Freq: 4 MHz max.
Freq: 10 MHz max.
Freq: 20 MHz max.
VDD: 4.0V to 6.0V
IDD: 52.5 µA typ. at
32 kHz, 4.0V
IPD: 0.9 µA typ. at 4.0V
Freq: 200 kHz max.
VDD: 3.0V to 6.0V
IDD: 48 µA max. at
32 kHz, 3.0V
IPD: 13.5 µA max. at 3.0V IPD: 13.5 µA max. at 3.0V
Freq: 200 kHz max.
VDD: 3.0V to 6.0V
IDD: 48 µA max. at
32 kHz, 3.0V
Not recommended for
use in LP mode
Not recommended for
use in LP mode
LP
Freq: 200 kHz max.
The shaded sections indicate oscillator selections which are tested for functionality, but not for MIN/MAX specifications.
It is recommended that the user select the device type that ensures the specifications required.
1997 Microchip Technology Inc.
DS30390E-page 183
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
18.1
DC Characteristics:
PIC16C73/74-04 (Commercial, Industrial)
PIC16C73/74-10 (Commercial, Industrial)
PIC16C73/74-20 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
DC CHARACTERISTICS
Operating temperature -40˚C ≤ TA ≤ +85˚C for industrial and
0˚C
≤ TA ≤ +70˚C for commercial
Param
No.
Characteristic
Sym
VDD
Min Typ† Max Units
Conditions
D001 Supply Voltage
D001A
4.0
4.5
-
-
6.0
5.5
V
V
XT, RC and LP osc configuration
HS osc configuration
D002* RAM Data Retention
Voltage (Note 1)
VDR
-
1.5
-
V
D003
VDD start voltage to
ensure internal Power-on
Reset signal
VPOR
-
VSS
-
V
See section on Power-on Reset for details
D004* VDD rise rate to ensure
internal Power-on Reset
signal
SVDD
0.05
-
-
V/ms See section on Power-on Reset for details
D010 Supply Current (Note 2,5) IDD
-
-
2.7
5
mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 5.5V (Note 4)
D013
13.5 30
10.5 42
1.5
1.5
mA HS osc configuration
FOSC = 20 MHz, VDD = 5.5V
D020 Power-down Current
D021 (Note 3,5)
D021A
IPD
-
-
-
µA VDD = 4.0V, WDT enabled, -40°C to +85°C
µA VDD = 4.0V, WDT disabled, -0°C to +70°C
µA VDD = 4.0V, WDT disabled, -40°C to +85°C
21
24
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
DS30390E-page 184
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
18.2
DC Characteristics: PIC16LC73/74-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
DC CHARACTERISTICS
Operating temperature -40˚C
0˚C
≤ TA ≤ +85˚C for industrial and
≤ TA ≤ +70˚C for commercial
Param
No.
Characteristic
Sym Min Typ† Max Units
Conditions
D001
Supply Voltage
VDD
VDR
3.0
-
-
6.0
-
V
V
LP, XT, RC osc configuration (DC - 4 MHz)
See section on Power-on Reset for details
D002* RAM Data Retention
Voltage (Note 1)
1.5
D003
VDD start voltage to
ensure internal Power-on
Reset signal
VPOR
SVDD
-
VSS
-
-
-
V
D004* VDD rise rate to ensure
internal Power-on Reset
signal
0.05
V/ms See section on Power-on Reset for details
D010
Supply Current (Note 2,5) IDD
-
-
2.0
3.8
mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 3.0V (Note 4)
D010A
22.5 48
7.5 30
µA LP osc configuration
FOSC = 32 kHz, VDD = 3.0V, WDT disabled
D020
D021
D021A
Power-down Current
(Note 3,5)
IPD
-
-
-
µA VDD = 3.0V, WDT enabled, -40°C to +85°C
0.9 13.5 µA VDD = 3.0V, WDT disabled, 0°C to +70°C
0.9 18 µA VDD = 3.0V, WDT disabled, -40°C to +85°C
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated.These parameters are for design guidance only
and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
1997 Microchip Technology Inc.
DS30390E-page 185
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
18.3
DC Characteristics:
PIC16C73/74-04 (Commercial, Industrial)
PIC16C73/74-10 (Commercial, Industrial)
PIC16C73/74-20 (Commercial, Industrial)
PIC16LC73/74-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +85˚C for industrial and
0˚C ≤ TA ≤ +70˚C for commercial
DC CHARACTERISTICS
Operating voltage VDD range as described in DC spec Section 18.1 and
Section 18.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Input Low Voltage
I/O ports
VIL
D030
D030A
D031
D032
D033
with TTL buffer
VSS
VSS
VSS
VSS
VSS
-
-
-
-
-
0.15VDD
0.8V
0.2VDD
0.2VDD
0.3VDD
V
V
V
V
V
For entire VDD range
4.5V ≤ VDD ≤ 5.5V
with Schmitt Trigger buffer
MCLR, OSC1 (in RC mode)
OSC1 (in XT, HS and LP)
Input High Voltage
I/O ports
Note1
VIH
-
-
-
D040
D040A
with TTL buffer
2.0
0.25VDD
+ 0.8V
VDD
VDD
V
V
4.5V ≤ VDD ≤ 5.5V
For entire VDD range
D041
D042
with Schmitt Trigger buffer
MCLR
0.8VDD
0.8VDD
0.7VDD
0.9VDD
50
-
-
-
-
VDD
VDD
VDD
VDD
V
V
V
V
For entire VDD range
Note1
D042A OSC1 (XT, HS and LP)
D043
D070
OSC1 (in RC mode)
PORTB weak pull-up current
Input Leakage Current
(Notes 2, 3)
IPURB
IIL
250 400
µA VDD = 5V, VPIN = VSS
D060
I/O ports
-
-
±1
µA Vss ≤ VPIN ≤ VDD, Pin at hi-imped-
ance
D061
D063
MCLR, RA4/T0CKI
OSC1
-
-
-
-
±5
±5
µA Vss ≤ VPIN ≤ VDD
µA Vss ≤ VPIN ≤ VDD, XT, HS and LP osc
configuration
Output Low Voltage
D080
D083
I/O ports
VOL
-
-
-
-
0.6
0.6
V
V
IOL = 8.5 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
OSC2/CLKOUT (RC osc config)
Output High Voltage
D090
D092
I/O ports (Note 3)
VOH VDD - 0.7 -
VDD - 0.7 -
-
-
V
V
V
IOH = -3.0 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
OSC2/CLKOUT (RC osc config)
D150* Open-Drain High Voltage
VOD
-
-
14
RA4 pin
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
DS30390E-page 186
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +85˚C for industrial and
0˚C ≤ TA ≤ +70˚C for commercial
DC CHARACTERISTICS
Operating voltage VDD range as described in DC spec Section 18.1 and
Section 18.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Capacitive Loading Specs on
Output Pins
D100
OSC2 pin
COSC2
-
-
15
pF In XT, HS and LP modes when exter-
nal clock is used to drive OSC1.
D101
D102
All I/O pins and OSC2 (in RC
CIO
CB
-
-
-
-
50
400
pF
pF
2
mode) SCL, SDA in I C mode
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
1997 Microchip Technology Inc.
DS30390E-page 187
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
18.4
Timing Parameter Symbology
The timing parameter symbols have been created following one of the following formats:
2
1. TppS2ppS
2. TppS
3. TCC:ST
4. Ts
(I C specifications only)
2
(I C specifications only)
T
F
Frequency
T
Time
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
CLKOUT
CS
osc
rd
OSC1
RD
ck
cs
di
rw
sc
ss
t0
RD or WR
SCK
SDI
do
dt
SDO
SS
Data in
I/O port
MCLR
T0CKI
T1CKI
WR
io
t1
mc
wr
Uppercase letters and their meanings:
S
F
H
I
Fall
P
R
V
Z
Period
High
Rise
Invalid (Hi-impedance)
Low
Valid
L
Hi-impedance
2
I C only
AA
output access
Bus free
High
Low
High
Low
BUF
2
TCC:ST (I C specifications only)
CC
HD
ST
DAT
STA
Hold
SU
Setup
DATA input hold
START condition
STO
STOP condition
FIGURE 18-1: LOAD CONDITIONS
Load condition 1
Load condition 2
VDD/2
RL
CL
CL
Pin
Pin
VSS
VSS
RL = 464Ω
CL = 50 pF for all pins except OSC2, but including PORTD and PORTE outputs as
ports
15 pF for OSC2 output
Note: PORTD and PORTE are not implemented on the PIC16C73.
DS30390E-page 188
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
18.5
Timing Diagrams and Specifications
FIGURE 18-2: EXTERNAL CLOCK TIMING
Q4
Q1
1
Q2
Q3
Q4
4
Q1
OSC1
3
3
4
2
CLKOUT
TABLE 18-2: EXTERNAL CLOCK TIMING REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units Conditions
Fosc External CLKIN Frequency
DC
DC
DC
DC
DC
DC
0.1
—
—
—
—
—
—
—
4
4
MHz XT and RC osc mode
MHz HS osc mode (-04)
MHz HS osc mode (-10)
MHz HS osc mode (-20)
kHz LP osc mode
(Note 1)
10
20
200
4
Oscillator Frequency
(Note 1)
MHz RC osc mode
4
MHz XT osc mode
4
5
—
—
20
200
MHz HS osc mode
kHz LP osc mode
1
Tosc External CLKIN Period
250
250
100
50
—
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
µs
ns
ns
ns
XT and RC osc mode
HS osc mode (-04)
HS osc mode (-10)
HS osc mode (-20)
LP osc mode
(Note 1)
—
—
5
—
Oscillator Period
(Note 1)
250
250
250
—
RC osc mode
10,000
250
XT osc mode
HS osc mode (-04)
100
50
—
—
250
250
ns
ns
HS osc mode (-10)
HS osc mode (-20)
5
200
50
2.5
15
—
—
—
—
—
—
—
—
—
—
DC
—
µs
ns
ns
µs
ns
ns
ns
ns
LP osc mode
TCY = 4/FOSC
XT oscillator
LP oscillator
HS oscillator
XT oscillator
LP oscillator
HS oscillator
2
3
TCY
Instruction Cycle Time (Note 1)
TosL, External Clock in (OSC1) High or
TosH Low Time
—
—
4
TosR, External Clock in (OSC1) Rise or
TosF Fall Time
25
50
15
—
—
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are based on
characterization data for that particular oscillator type under standard operating conditions with the device executing code.
Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current con-
sumption. All devices are tested to operate at "min." values with an external clock applied to the OSC1/CLKIN pin.
When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices.
1997 Microchip Technology Inc.
DS30390E-page 189
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-3: CLKOUT AND I/O TIMING
Q1
Q2
Q3
Q4
OSC1
11
10
CLKOUT
13
14
12
18
19
16
I/O Pin
(input)
15
17
I/O Pin
new value
old value
(output)
20, 21
Note: Refer to Figure 18-1 for load conditions.
TABLE 18-3: CLKOUT AND I/O TIMING REQUIREMENTS
Parameter Sym
No.
Characteristic
Min
Typ†
Max
Units Conditions
10*
11*
12*
13*
14*
15*
16*
17*
TosH2ckL OSC1↑ to CLKOUT↓
TosH2ckH OSC1↑ to CLKOUT↑
—
—
—
—
—
75
75
35
35
—
—
—
50
200
200
ns
ns
ns
ns
ns
ns
ns
ns
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
TckR
TckF
CLKOUT rise time
CLKOUT fall time
100
100
TckL2ioV CLKOUT ↓ to Port out valid
TioV2ckH Port in valid before CLKOUT ↑
0.5TCY + 20
—
0.25TCY + 25
TckH2ioI
Port in hold after CLKOUT ↑
0
—
TosH2ioV OSC1↑ (Q1 cycle) to
—
150
Port out valid
18*
TosH2ioI
OSC1↑ (Q2 cycle) to
Port input invalid (I/O in
hold time)
PIC16C73/74
100
200
—
—
—
—
ns
ns
PIC16LC73/74
19*
20*
TioV2osH Port input valid to OSC1↑ (I/O in setup time)
0
—
—
10
—
10
—
—
—
—
25
60
25
60
—
—
ns
ns
ns
ns
ns
ns
ns
TioR
Port output rise time
Port output fall time
INT pin high or low time
PIC16C73/74
PIC16LC73/74
PIC16C73/74
PIC16LC73/74
—
21*
TioF
—
—
22††*
23††*
Tinp
Trbp
TCY
TCY
RB7:RB4 change INT high or low time
* These parameters are characterized but not tested.
†Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance
only and are not tested.
†† These parameters are asynchronous events not related to any internal clock edges.
Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC.
DS30390E-page 190
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Time-out
Internal
RESET
Watchdog
Timer
RESET
31
34
34
I/O Pins
Note: Refer to Figure 18-1 for load conditions.
TABLE 18-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max Units
Conditions
30
TmcL MCLR Pulse Width (low)
100
7
—
—
ns VDD = 5V, -40˚C to +85˚C
ms VDD = 5V, -40˚C to +85˚C
31*
Twdt
Watchdog Timer Time-out Period
18
33
(No Prescaler)
32
33*
34
Tost
Oscillation Start-up Timer Period
—
28
—
1024TOSC
—
—
TOSC = OSC1 period
Tpwrt Power up Timer Period
I/O Hi-impedance from MCLR Low
or Watchdog Timer Reset
These parameters are characterized but not tested.
72
—
132
100
ms VDD = 5V, -40˚C to +85˚C
ns
TIOZ
*
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 191
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-5: TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
RA4/T0CKI
41
40
42
RC0/T1OSO/T1CKI
46
45
47
48
TMR0 or
TMR1
Note: Refer to Figure 18-1 for load conditions.
TABLE 18-5: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Sym
Characteristic
Min
Typ† Max Units Conditions
40*
Tt0H
T0CKI High Pulse Width
No Prescaler
0.5TCY + 20
—
—
ns Must also meet
parameter 42
With Prescaler
No Prescaler
10
0.5TCY + 20
10
—
—
—
—
—
—
—
—
—
—
ns
41*
42*
Tt0L
Tt0P
T0CKI Low Pulse Width
T0CKI Period
ns Must also meet
parameter 42
With Prescaler
No Prescaler
With Prescaler
ns
ns
TCY + 40
Greater of:
20 or TCY + 40
ns N = prescale value
(2, 4, ..., 256)
N
0.5TCY + 20
15
45*
46*
47*
Tt1H
Tt1L
Tt1P
T1CKI High Time Synchronous, Prescaler = 1
—
—
—
—
—
—
ns Must also meet
parameter 47
Synchronous, PIC16C7X
ns
ns
Prescaler =
2,4,8
PIC16LC7X
25
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
—
—
—
—
ns
ns
50
T1CKI Low Time
Synchronous, Prescaler = 1
Synchronous, PIC16C7X
0.5TCY + 20
ns Must also meet
parameter 47
15
25
ns
ns
Prescaler =
2,4,8
PIC16LC7X
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
ns
ns
50
T1CKI input period Synchronous PIC16C7X
Greater of:
30 OR TCY + 40
ns N = prescale value
(1, 2, 4, 8)
N
Greater of:
50 OR TCY + 40
N = prescale value
(1, 2, 4, 8)
PIC16LC7X
N
60
Asynchronous PIC16C7X
PIC16LC7X
—
—
—
—
—
ns
ns
100
DC
Ft1
Timer1 oscillator input frequency range
(oscillator enabled by setting bit T1OSCEN)
200
kHz
48
*
TCKEZtmr1 Delay from external clock edge to timer increment
2Tosc
—
7Tosc
—
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 192
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-6: CAPTURE/COMPARE/PWM TIMINGS (CCP1 AND CCP2)
RC1/T1OSI/CCP2
and RC2/CCP1
(Capture Mode)
50
51
52
RC1/T1OSI/CCP2
and RC2/CCP1
(Compare or PWM Mode)
53
Note: Refer to Figure 18-1 for load conditions.
54
TABLE 18-6: CAPTURE/COMPARE/PWM REQUIREMENTS (CCP1 AND CCP2)
Parameter Sym Characteristic
No.
Min
Typ† Max Units Conditions
50*
TccL CCP1 and CCP2 No Prescaler
input low time
0.5TCY + 20
—
—
ns
PIC16C73/74
10
—
—
—
—
—
—
—
—
ns
ns
ns
ns
With Prescaler
PIC16LC73/74
20
0.5TCY + 20
10
51*
TccH
No Prescaler
CCP1 and CCP2
input high time
PIC16C73/74
With Prescaler
PIC16LC73/74
20
—
—
—
—
ns
52*
53*
TccP
3TCY + 40
N
ns N = prescale value
(1,4 or 16)
CCP1 and CCP2 input period
TccR CCP1 and CCP2 output fall time
TccF CCP1 and CCP2 output fall time
PIC16C73/74
PIC16LC73/74
PIC16C73/74
PIC16LC73/74
—
—
—
—
10
25
10
25
25
45
25
45
ns
ns
ns
ns
54*
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 193
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-7: PARALLEL SLAVE PORT TIMING (PIC16C74)
RE2/CS
RE0/RD
RE1/WR
65
RD7:RD0
62
64
63
Note: Refer to Figure 18-1 for load conditions
TABLE 18-7: PARALLEL SLAVE PORT REQUIREMENTS (PIC16C74)
Parameter
No.
Sym
Characteristic
Min Typ† Max Units Conditions
62
TdtV2wrH Data in valid before WR↑ or CS↑ (setup time)
TwrH2dtI WR↑ or CS↑ to data–in invalid (hold time)
20
20
35
—
10
—
—
—
—
—
—
—
—
80
30
ns
ns
ns
ns
ns
63*
PIC16C74
PIC16LC74
64
65
TrdL2dtV RD↓ and CS↓ to data–out valid
TrdH2dtI RD↑ or CS↓ to data–out invalid
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 194
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-8: SPI MODE TIMING
SS
70
SCK
(CKP = 0)
71
72
78
79
79
78
SCK
(CKP = 1)
80
SDO
77
75, 76
SDI
74
73
Note: Refer to Figure 18-1 for load conditions
TABLE 18-8: SPI MODE REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max
Units
Conditions
70
TssL2scH,
TssL2scL
SS↓ to SCK↓ or SCK↑ input
TCY
—
—
ns
71
72
73
TscH
TscL
SCK input high time (slave mode)
SCK input low time (slave mode)
TCY + 20
TCY + 20
50
—
—
—
—
—
—
ns
ns
ns
TdiV2scH,
TdiV2scL
Setup time of SDI data input to SCK
edge
74
TscH2diL,
TscL2diL
Hold time of SDI data input to SCK
edge
50
—
—
ns
75
76
77
78
79
80
TdoR
SDO data output rise time
—
—
10
—
—
—
10
10
—
10
10
—
25
25
50
25
25
50
ns
ns
ns
ns
ns
ns
TdoF
SDO data output fall time
TssH2doZ
TscR
SS↑ to SDO output hi-impedance
SCK output rise time (master mode)
SCK output fall time (master mode)
TscF
TscH2doV,
TscL2doV
SDO data output valid after SCK
edge
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 195
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 18-9: I C BUS START/STOP BITS TIMING
SCL
93
91
90
92
SDA
STOP
Condition
START
Condition
Note: Refer to Figure 18-1 for load conditions
2
TABLE 18-9: I C BUS START/STOP BITS REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min Typ Max Units
Conditions
90
91
92
93
TSU:STA START condition
Setup time
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
4700
600
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Only relevant for repeated START
condition
ns
ns
ns
ns
THD:STA START condition
Hold time
4000
600
After this period the first clock
pulse is generated
TSU:STO STOP condition
Setup time
4700
600
THD:STO STOP condition
Hold time
4000
600
DS30390E-page 196
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 18-10: I C BUS DATA TIMING
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
Note: Refer to Figure 18-1 for load conditions
2
TABLE 18-10: I C BUS DATA REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Max
Units
Conditions
100
THIGH
Clock high time
100 kHz mode
400 kHz mode
4.0
0.6
—
—
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
4.7
—
—
101
TLOW
Clock low time
100 kHz mode
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
400 kHz mode
1.3
—
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
—
—
102
103
TR
TF
SDA and SCL rise
time
100 kHz mode
400 kHz mode
1000
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
SDA and SCL fall time 100 kHz mode
400 kHz mode
—
300
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
90
91
TSU:STA START condition
setup time
100 kHz mode
400 kHz mode
4.7
0.6
4.0
0.6
0
—
—
µs
µs
µs
µs
ns
µs
ns
ns
µs
µs
ns
ns
µs
µs
Only relevant for repeated
START condition
THD:STA START condition hold 100 kHz mode
—
After this period the first clock
pulse is generated
time
400 kHz mode
100 kHz mode
400 kHz mode
—
106
107
92
THD:DAT Data input hold time
—
0
0.9
—
TSU:DAT Data input setup time 100 kHz mode
400 kHz mode
250
100
4.7
0.6
—
Note 2
—
TSU:STO STOP condition setup 100 kHz mode
—
time
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
—
109
110
TAA
Output valid from
clock
3500
—
Note 1
—
TBUF
Bus free time
4.7
1.3
—
Time the bus must be free
before a new transmission can
start
—
Cb
Bus capacitive loading
—
400
pF
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of
the falling edge of SCL to avoid unintended generation of START or STOP conditions.
2
2
2: A fast-mode (400 kHz) I C-bus device can be used in a standard-mode (100 kHz) I C-bus system, but the requirement
tsu;DAT ≥ 250 ns must then be met.This will automatically be the case if the device does not stretch the LOW period of the
SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line
2
TR max.+tsu;DAT = 1000 + 250 = 1250 ns (according to the standard-mode I C bus specification) before the SCL line is
released.
1997 Microchip Technology Inc.
DS30390E-page 197
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-11: USART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
RC6/TX/CK
121
pin
121
RC7/RX/DT
pin
120
122
Note: Refer to Figure 18-1 for load conditions
TABLE 18-11: USART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ† Max Units Conditions
120
TckH2dtV
SYNC XMIT (MASTER &
SLAVE)
Clock high to data out valid
PIC16C73/74
—
—
—
—
—
—
—
—
—
—
—
—
80
100
45
ns
ns
ns
ns
ns
ns
PIC16LC73/74
121
122
Tckrf
Tdtrf
Clock out rise time and fall time PIC16C73/74
(Master Mode)
PIC16LC73/74
50
Data out rise time and fall time
PIC16C73/74
45
PIC16LC73/74
50
†:
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
FIGURE 18-12: USART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
RC6/TX/CK
125
pin
RC7/RX/DT
pin
126
Note: Refer to Figure 18-1 for load conditions
TABLE 18-12: USART SYNCHRONOUS RECEIVE REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max
Units Conditions
125
TdtV2ckL
SYNC RCV (MASTER & SLAVE)
Data setup before CK ↓ (DT setup time)
15
15
—
—
—
—
ns
ns
126
TckL2dtl
Data hold after CK ↓ (DT hold time)
†:
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 198
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
TABLE 18-13: A/D CONVERTER CHARACTERISTICS:
PIC16C73/74-04 (Commercial, Industrial)
PIC16C73/74-10 (Commercial, Industrial)
PIC16C73/74-20 (Commercial, Industrial)
PIC16LC73/74-04 (Commercial, Industrial)
Param Sym Characteristic
Min
Typ†
Max
Units
Conditions
No.
A01
NR Resolution
—
—
—
—
—
—
—
—
—
—
—
—
8-bits
bit VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A02 EABS Total Absolute error
< ± 1
< ± 1
< ± 1
< ± 1
< ± 1
LSb
LSb
LSb
LSb
LSb
A03
A04
A05
EIL Integral linearity error
EDL Differential linearity error
EFS Full scale error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A06 EOFF Offset error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A10
—
Monotonicity
—
3.0V
guaranteed
—
—
V
VSS ≤ VAIN ≤ VREF
A20 VREF Reference voltage
—
—
—
VDD + 0.3
VREF + 0.3
10.0
A25
A30
VAIN Analog input voltage
VSS - 0.3
—
V
ZAIN Recommended impedance of
analog voltage source
kΩ
A40
A50
IAD A/D conversion current PIC16C73/74
—
—
180
90
—
—
µA Average current consump-
(VDD)
tion when A/D is on.
(Note 1)
PIC16LC73/74
µA
IREF VREF input current (Note 2)
10
—
1000
µA During VAIN acquisition.
Based on differential of
VHOLD to VAIN to charge
CHOLD, see Section 13.1.
—
—
10
µA During A/D Conversion
cycle
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: When A/D is off, it will not consume any current other than minor leakage current.
The power-down current spec includes any such leakage from the A/D module.
2: VREF current is from RA3 pin or VDD pin, whichever is selected as reference input.
1997 Microchip Technology Inc.
DS30390E-page 199
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 18-13: A/D CONVERSION TIMING
BSF ADCON0, GO
1 TCY
134
(TOSC/2) (1)
131
130
Q4
132
A/D CLK
7
6
5
4
3
2
1
0
A/D DATA
NEW_DATA
DONE
OLD_DATA
ADRES
ADIF
GO
SAMPLING STOPPED
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the
SLEEPinstruction to be executed.
TABLE 18-14: A/D CONVERSION REQUIREMENTS
Param Sym Characteristic
No.
Min
Typ†
Max
Units
Conditions
130
TAD A/D clock period
PIC16C73/74
PIC16LC73/74
PIC16C73/74
PIC16LC73/74
1.6
2.0
2.0
3.0
—
—
—
—
—
µs
TOSC based, VREF ≥ 3.0V
µs TOSC based, VREF full range
µs A/D RC Mode
µs A/D RC Mode
TAD
4.0
6.0
9.5
6.0
9.0
—
131
132
TCNV Conversion time (not including S/H time)
(Note 1)
TACQ Acquisition time
Note 2
5*
20
—
—
—
µs
µs The minimum time is the amplifier
settling time. This may be used if
the "new" input voltage has not
changed by more than 1 LSb (i.e.,
20 mV @ 5.12V) from the last
sampled voltage (as stated on
CHOLD).
134
135
TGO Q4 to A/D clock start
—
TOSC/2 §
—
—
—
If the A/D clock source is selected
as RC, a time of TCY is added
before the A/D clock starts. This
allows the SLEEPinstruction to be
executed.
TSWC Switching from convert → sample time
1.5 §
—
TAD
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
§
This specification ensured by design.
Note 1: ADRES register may be read on the following TCY cycle.
2: See Section 13.1 for min conditions.
DS30390E-page 200
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
19.0 ELECTRICAL CHARACTERISTICS FOR PIC16C73A/74A
Absolute Maximum Ratings †
Ambient temperature under bias..................................................................................................................-55 to +125˚C
Storage temperature............................................................................................................................... -65˚C to +150˚C
Voltage on any pin with respect to VSS (except VDD, MCLR. and RA4)...........................................-0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ............................................................................................................ -0.3 to +7.5V
Voltage on MCLR with respect to VSS (Note 2) ................................................................................................. 0 to +14V
Voltage on RA4 with respect to Vss................................................................................................................... 0 to +14V
Total power dissipation (Note 1).................................................................................................................................1.0W
Maximum current out of VSS pin ............................................................................................................................300 mA
Maximum current into VDD pin...............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD) .....................................................................................................................±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD)..............................................................................................................±20 mA
Maximum output current sunk by any I/O pin...........................................................................................................25 mA
Maximum output current sourced by any I/O pin .....................................................................................................25 mA
Maximum current sunk by PORTA, PORTB, and PORTE (combined) (Note 3).....................................................200 mA
Maximum current sourced by PORTA, PORTB, and PORTE (combined) (Note 3) ...............................................200 mA
Maximum current sunk by PORTC and PORTD (combined) (Note 3)...................................................................200 mA
Maximum current sourced by PORTC and PORTD (combined) (Note 3)..............................................................200 mA
Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - ∑ IOH} + ∑ {(VDD - VOH) x IOH} + ∑(VOl x IOL)
Note 2: Voltage spikes below VSS at the MCLR pin, inducing currents greater than 80 mA, may cause latch-up.Thus,
a series resistor of 50-100Ω should be used when applying a “low” level to the MCLRpin rather than pulling
this pin directly to VSS.
Note 3: PORTD and PORTE are not implemented on the PIC16C73A.
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
TABLE 19-1: CROSS REFERENCE OF DEVICE SPECS FOR OSCILLATOR CONFIGURATIONS
AND FREQUENCIES OF OPERATION (COMMERCIAL DEVICES)
PIC16C73A-04
PIC16C74A-04
PIC16C73A-10
PIC16C74A-10
PIC16C73A-20
PIC16C74A-20
PIC16LC73A-04
PIC16LC74A-04
OSC
JW Devices
VDD: 4.0V to 6.0V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 2.5V to 6.0V
VDD: 4.0V to 6.0V
IDD: 5 mA max. at 5.5V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 3.8 mA max. at 3.0V IDD: 5 mA max. at 5.5V
RC
IPD: 5 µA max. at 3V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.0V to 6.0V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 2.5V to 6.0V
VDD: 4.0V to 6.0V
IDD: 5 mA max. at 5.5V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 2.7 mA typ. at 5.5V
IPD: 1.5 µA typ. at 4V
Freq: 4 MHz max.
IDD: 3.8 mA max. at 3.0V IDD: 5 mA max. at 5.5V
XT
HS
IPD: 5 µA max. at 3V
IPD: 16 µA max. at 4V
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
IDD: 13.5 mA typ. at 5.5V IDD: 10 mA max. at 5.5V IDD: 20 mA max. at 5.5V
IDD: 20 mA max. at 5.5V
IPD: 1.5 µA typ. at 4.5V
Freq: 20 MHz max.
Not recommended for
use in HS mode
IPD: 1.5 µA typ. at 4.5V
IPD: 1.5 µA typ. at 4.5V
IPD: 1.5 µA typ. at 4.5V
Freq: 4 MHz max.
Freq: 10 MHz max.
Freq: 20 MHz max.
VDD: 4.0V to 6.0V
IDD: 52.5 µA typ. at
32 kHz, 4.0V
IPD: 0.9 µA typ. at 4.0V
Freq: 200 kHz max.
VDD: 2.5V to 6.0V
IDD: 48 µA max. at
32 kHz, 3.0V
IPD: 5.0 µA max. at 3.0V
Freq: 200 kHz max.
VDD: 2.5V to 6.0V
IDD: 48 µA max. at
32 kHz, 3.0V
IPD: 5.0 µA max. at 3.0V
Freq: 200 kHz max.
Not recommended for
use in LP mode
Not recommended for
use in LP mode
LP
The shaded sections indicate oscillator selections which are tested for functionality, but not for MIN/MAX specifications.
It is recommended that the user select the device type that ensures the specifications required.
1997 Microchip Technology Inc.
DS30390E-page 201
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
19.1
DC Characteristics:
PIC16C73A/74A-04 (Commercial, Industrial, Extended)
PIC16C73A/74A-10 (Commercial, Industrial, Extended)
PIC16C73A/74A-20 (Commercial, Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40˚C ≤ TA ≤ +125˚C for extended,
DC CHARACTERISTICS
-40˚C
0˚C
≤ TA ≤ +85˚C for industrial and
≤ TA ≤ +70˚C for commercial
Param
No.
Characteristic
Sym
VDD
Min Typ† Max Units
Conditions
D001 Supply Voltage
D001A
4.0
4.5
-
-
6.0
5.5
V
V
XT, RC and LP osc configuration
HS osc configuration
D002* RAM Data Retention
Voltage (Note 1)
VDR
-
1.5
-
V
D003
VDD start voltage to
ensure internal Power-on
Reset signal
VPOR
-
VSS
-
V
See section on Power-on Reset for details
D004* VDD rise rate to ensure
internal Power-on Reset
signal
SVDD
0.05
-
-
V/ms See section on Power-on Reset for details
D005 Brown-out Reset Voltage BVDD
3.7
3.7
-
4.0 4.3
4.0 4.4
V
V
BODEN bit in configuration word enabled
Extended Range Only
D010 Supply Current (Note 2,5) IDD
2.7
5
mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 5.5V (Note 4)
D013
-
-
10
20
mA HS osc configuration
FOSC = 20 MHz, VDD = 5.5V
D015* Brown-out Reset Current ∆IBOR
350 425 µA BOR enabled VDD = 5.0V
(Note 6)
D020 Power-down Current
D021 (Note 3,5)
D021A
IPD
-
-
-
-
10.5 42 µA VDD = 4.0V, WDT enabled, -40°C to +85°C
1.5
1.5
2.5
16
19
19
µA VDD = 4.0V, WDT disabled, -0°C to +70°C
µA VDD = 4.0V, WDT disabled, -40°C to +85°C
µA VDD = 4.0V, WDT disabled, -40°C to +125°C
D021B
D023* Brown-out Reset Current ∆IBOR
-
350 425 µA BOR enabled VDD = 5.0V
(Note 6)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
6: The ∆ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
DS30390E-page 202
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
19.2
DC Characteristics: PIC16LC73A/74A-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
DC CHARACTERISTICS
Operating temperature -40˚C
0˚C
≤ TA ≤ +85˚C for industrial and
≤ TA ≤ +70˚C for commercial
Param
No.
Characteristic
Sym Min Typ† Max Units
Conditions
D001
Supply Voltage
VDD
VDR
2.5
-
-
6.0
-
V
V
LP, XT, RC osc configuration (DC - 4 MHz)
See section on Power-on Reset for details
D002* RAM Data Retention
Voltage (Note 1)
1.5
D003
VDD start voltage to
ensure internal Power-on
Reset signal
VPOR
SVDD
-
VSS
-
-
-
V
D004* VDD rise rate to ensure
internal Power-on Reset
signal
0.05
V/ms See section on Power-on Reset for details
D005
D010
Brown-out Reset Voltage BVDD
Supply Current (Note 2,5) IDD
3.7
-
4.0
2.0
4.3
3.8
V
BODEN bit in configuration word enabled
mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 3.0V (Note 4)
D010A
-
-
22.5 48
350 425
µA LP osc configuration
FOSC = 32 kHz, VDD = 3.0V, WDT disabled
D015* Brown-out Reset Current ∆IBOR
µA BOR enabled VDD = 5.0V
(Note 6)
D020
D021
D021A
Power-down Current
(Note 3,5)
IPD
-
-
-
7.5
0.9
0.9
30
5
5
µA VDD = 3.0V, WDT enabled, -40°C to +85°C
µA VDD = 3.0V, WDT disabled, 0°C to +70°C
µA VDD = 3.0V, WDT disabled, -40°C to +85°C
D023* Brown-out Reset Current ∆IBOR
-
350 425
µA BOR enabled VDD = 5.0V
(Note 6)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated.These parameters are for design guidance only
and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
6: The ∆ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
1997 Microchip Technology Inc.
DS30390E-page 203
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
19.3
DC Characteristics:
PIC16C73A/74A-04 (Commercial, Industrial, Extended)
PIC16C73A/74A-10 (Commercial, Industrial, Extended)
PIC16C73A/74A-20 (Commercial, Industrial, Extended)
PIC16LC73A/74A-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +125˚C for extended,
-40˚C ≤ TA ≤ +85˚C for industrial and
DC CHARACTERISTICS
0˚C
≤ TA ≤ +70˚C for commercial
Operating voltage VDD range as described in DC spec Section 19.1 and
Section 19.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Input Low Voltage
I/O ports
VIL
D030
D030A
D031
D032
D033
with TTL buffer
VSS
VSS
VSS
VSS
VSS
-
-
-
-
-
0.15VDD
0.8V
0.2VDD
0.2VDD
0.3VDD
V
For entire VDD range
4.5V ≤ VDD ≤ 5.5V
with Schmitt Trigger buffer
MCLR, OSC1 (in RC mode)
OSC1 (in XT, HS and LP)
Input High Voltage
I/O ports
V
V
V
Note1
VIH
-
-
-
D040
D040A
with TTL buffer
2.0
0.25VDD
+ 0.8V
VDD
VDD
V
V
4.5V ≤ VDD ≤ 5.5V
For entire VDD range
D041
D042
with Schmitt Trigger buffer
MCLR
0.8VDD
0.8VDD
0.7VDD
0.9VDD
50
-
-
-
-
VDD
VDD
VDD
VDD
V
V
V
V
For entire VDD range
Note1
D042A OSC1 (XT, HS and LP)
D043
D070
OSC1 (in RC mode)
PORTB weak pull-up current
Input Leakage Current
(Notes 2, 3)
IPURB
IIL
250 400
µA VDD = 5V, VPIN = VSS
D060
I/O ports
-
-
±1
µA Vss ≤ VPIN ≤ VDD, Pin at hi-imped-
ance
D061
D063
MCLR, RA4/T0CKI
OSC1
-
-
-
-
±5
±5
µA Vss ≤ VPIN ≤ VDD
µA Vss ≤ VPIN ≤ VDD, XT, HS and LP osc
configuration
Output Low Voltage
D080
I/O ports
VOL
-
-
-
-
-
-
-
-
0.6
0.6
0.6
0.6
V
V
V
V
IOL = 8.5 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 7.0 mA, VDD = 4.5V,
-40°C to +125°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.2 mA, VDD = 4.5V,
-40°C to +125°C
D080A
D083
OSC2/CLKOUT (RC osc config)
D083A
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
DS30390E-page 204
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +125˚C for extended,
-40˚C ≤ TA ≤ +85˚C for industrial and
DC CHARACTERISTICS
0˚C
≤ TA ≤ +70˚C for commercial
Operating voltage VDD range as described in DC spec Section 19.1 and
Section 19.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Output High Voltage
D090
I/O ports (Note 3)
VOH VDD - 0.7 -
VDD - 0.7 -
-
-
V
V
V
V
V
IOH = -3.0 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -2.5 mA, VDD = 4.5V,
-40°C to +125°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.0 mA, VDD = 4.5V,
-40°C to +125°C
D090A
D092
OSC2/CLKOUT (RC osc config)
VDD - 0.7 -
-
D092A
VDD - 0.7 -
-
D150* Open-Drain High Voltage
Capacitive Loading Specs on
Output Pins
VOD
-
-
-
-
14
RA4 pin
D100
OSC2 pin
COSC2
15
pF In XT, HS and LP modes when exter-
nal clock is used to drive OSC1.
D101
D102
All I/O pins and OSC2 (in RC
CIO
CB
-
-
-
-
50
400
pF
pF
2
mode) SCL, SDA in I C mode
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
1997 Microchip Technology Inc.
DS30390E-page 205
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
19.4
Timing Parameter Symbology
The timing parameter symbols have been created following one of the following formats:
2
1. TppS2ppS
2. TppS
3. TCC:ST
4. Ts
(I C specifications only)
2
(I C specifications only)
T
F
Frequency
T
Time
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
CLKOUT
CS
osc
rd
OSC1
RD
ck
cs
di
rw
sc
ss
t0
RD or WR
SCK
SDI
do
dt
SDO
SS
Data in
I/O port
MCLR
T0CKI
T1CKI
WR
io
t1
mc
wr
Uppercase letters and their meanings:
S
F
H
I
Fall
P
R
V
Z
Period
High
Rise
Invalid (Hi-impedance)
Low
Valid
L
Hi-impedance
2
I C only
AA
output access
Bus free
High
Low
High
Low
BUF
2
TCC:ST (I C specifications only)
CC
HD
ST
DAT
STA
Hold
SU
Setup
DATA input hold
START condition
STO
STOP condition
FIGURE 19-1: LOAD CONDITIONS
Load condition 1
Load condition 2
VDD/2
RL
CL
CL
Pin
Pin
VSS
VSS
RL = 464Ω
CL = 50 pF for all pins except OSC2, but including PORTD and PORTE outputs as
ports
15 pF for OSC2 output
Note: PORTD and PORTE are not implemented on the PIC16C73A.
DS30390E-page 206
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
19.5
Timing Diagrams and Specifications
FIGURE 19-2: EXTERNAL CLOCK TIMING
Q4
Q1
1
Q2
Q3
Q4
4
Q1
OSC1
3
3
4
2
CLKOUT
TABLE 19-2: EXTERNAL CLOCK TIMING REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units Conditions
Fosc External CLKIN Frequency
DC
DC
DC
DC
DC
DC
0.1
—
—
—
—
—
—
—
4
4
MHz XT and RC osc mode
MHz HS osc mode (-04)
MHz HS osc mode (-10)
MHz HS osc mode (-20)
kHz LP osc mode
(Note 1)
10
20
200
4
Oscillator Frequency
(Note 1)
MHz RC osc mode
4
MHz XT osc mode
4
5
—
—
20
200
MHz HS osc mode
kHz LP osc mode
1
Tosc External CLKIN Period
250
250
100
50
—
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
µs
ns
ns
ns
XT and RC osc mode
HS osc mode (-04)
HS osc mode (-10)
HS osc mode (-20)
LP osc mode
(Note 1)
—
—
5
—
Oscillator Period
(Note 1)
250
250
250
—
RC osc mode
10,000
250
XT osc mode
HS osc mode (-04)
100
50
—
—
250
250
ns
ns
HS osc mode (-10)
HS osc mode (-20)
5
—
TCY
—
—
DC
—
µs
ns
ns
µs
ns
ns
ns
ns
LP osc mode
TCY = 4/FOSC
XT oscillator
LP oscillator
HS oscillator
XT oscillator
LP oscillator
HS oscillator
2
3
TCY
Instruction Cycle Time (Note 1)
200
100
2.5
15
TosL, External Clock in (OSC1) High or
TosH Low Time
—
—
—
—
4
TosR, External Clock in (OSC1) Rise or
TosF Fall Time
—
—
25
50
15
—
—
—
—
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are based on
characterization data for that particular oscillator type under standard operating conditions with the device executing code.
Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current con-
sumption. All devices are tested to operate at "min." values with an external clock applied to the OSC1/CLKIN pin.
When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices.
1997 Microchip Technology Inc.
DS30390E-page 207
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-3: CLKOUT AND I/O TIMING
Q1
Q2
Q3
Q4
OSC1
11
10
CLKOUT
13
14
12
18
19
16
I/O Pin
(input)
15
17
I/O Pin
new value
old value
(output)
20, 21
Note: Refer to Figure 19-1 for load conditions.
TABLE 19-3: CLKOUT AND I/O TIMING REQUIREMENTS
Param Sym
No.
Characteristic
Min
Typ†
Max
Units Conditions
10*
11*
12*
13*
14*
15*
16*
17*
TosH2ckL OSC1↑ to CLKOUT↓
TosH2ckH OSC1↑ to CLKOUT↑
—
75
75
35
35
—
—
—
50
200
200
ns
ns
ns
ns
ns
ns
ns
ns
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
—
TckR
TckF
CLKOUT rise time
CLKOUT fall time
—
100
—
100
TckL2ioV CLKOUT ↓ to Port out valid
TioV2ckH Port in valid before CLKOUT ↑
TckH2ioI Port in hold after CLKOUT ↑
—
0.5TCY + 20
—
TOSC + 200
0
—
TosH2ioV OSC1↑ (Q1 cycle) to
—
150
Port out valid
18*
TosH2ioI OSC1↑ (Q2 cycle) to
Port input invalid (I/O in
hold time)
PIC16C73A/74A
PIC16LC73A/74A
100
200
—
—
—
—
ns
ns
19*
20*
TioV2osH Port input valid to OSC1↑ (I/O in setup time)
0
—
—
10
—
10
—
—
—
—
40
80
40
80
—
—
ns
ns
ns
ns
ns
ns
ns
TioR
Port output rise time
Port output fall time
INT pin high or low time
PIC16C73A/74A
PIC16LC73A/74A
PIC16C73A/74A
PIC16LC73A/74A
—
21*
TioF
—
—
22††* Tinp
23††* Trbp
TCY
TCY
RB7:RB4 change INT high or low time
* These parameters are characterized but not tested.
†Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance
only and are not tested.
†† These parameters are asynchronous events not related to any internal clock edges.
Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC.
DS30390E-page 208
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Time-out
Internal
RESET
Watchdog
Timer
RESET
31
34
34
I/O Pins
Note: Refer to Figure 19-1 for load conditions.
FIGURE 19-5: BROWN-OUT RESET TIMING
BVDD
VDD
35
TABLE 19-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER,
AND BROWN-OUT RESET REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max Units
Conditions
30
TmcL MCLR Pulse Width (low)
2
7
—
—
µs VDD = 5V, -40˚C to +125˚C
31*
Twdt
Watchdog Timer Time-out Period
18
33
ms VDD = 5V, -40˚C to +125˚C
(No Prescaler)
32
33*
34
Tost
Oscillation Start-up Timer Period
—
28
—
1024TOSC
—
—
TOSC = OSC1 period
Tpwrt Power up Timer Period
72
—
132
2.1
ms VDD = 5V, -40˚C to +125˚C
TIOZ
I/O Hi-impedance from MCLR Low
µs
or Watchdog Timer Reset
35
TBOR
Brown-out Reset pulse width
100
—
—
µs
VDD ≤ BVDD (D005)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 209
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-6: TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
RA4/T0CKI
41
40
42
RC0/T1OSO/T1CKI
46
45
47
48
TMR0 or
TMR1
Note: Refer to Figure 19-1 for load conditions.
TABLE 19-5: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Sym
Characteristic
Min
Typ† Max Units Conditions
40*
Tt0H
T0CKI High Pulse Width
No Prescaler
0.5TCY + 20
—
—
ns Must also meet
parameter 42
With Prescaler
No Prescaler
10
0.5TCY + 20
10
—
—
—
—
—
—
—
—
—
—
ns
41*
42*
Tt0L
Tt0P
T0CKI Low Pulse Width
T0CKI Period
ns Must also meet
parameter 42
With Prescaler
No Prescaler
With Prescaler
ns
ns
TCY + 40
Greater of:
20 or TCY + 40
ns N = prescale value
(2, 4, ..., 256)
N
0.5TCY + 20
15
45*
46*
47*
Tt1H
Tt1L
Tt1P
T1CKI High Time Synchronous, Prescaler = 1
—
—
—
—
—
—
ns Must also meet
parameter 47
Synchronous, PIC16C7X
ns
ns
Prescaler =
2,4,8
PIC16LC7X
25
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
—
—
—
—
ns
ns
50
T1CKI Low Time
Synchronous, Prescaler = 1
Synchronous, PIC16C7X
0.5TCY + 20
ns Must also meet
parameter 47
15
25
ns
ns
Prescaler =
2,4,8
PIC16LC7X
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
ns
ns
50
T1CKI input period Synchronous PIC16C7X
Greater of:
30 OR TCY + 40
ns N = prescale value
(1, 2, 4, 8)
N
Greater of:
50 OR TCY + 40
N = prescale value
(1, 2, 4, 8)
PIC16LC7X
N
60
Asynchronous PIC16C7X
PIC16LC7X
—
—
—
—
—
ns
ns
100
DC
Ft1
Timer1 oscillator input frequency range
(oscillator enabled by setting bit T1OSCEN)
200
kHz
48
*
TCKEZtmr1 Delay from external clock edge to timer increment
2Tosc
—
7Tosc
—
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 210
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-7: CAPTURE/COMPARE/PWM TIMINGS (CCP1 AND CCP2)
RC1/T1OSI/CCP2
and RC2/CCP1
(Capture Mode)
50
51
52
RC1/T1OSI/CCP2
and RC2/CCP1
(Compare or PWM Mode)
53
Note: Refer to Figure 19-1 for load conditions.
54
TABLE 19-6: CAPTURE/COMPARE/PWM REQUIREMENTS (CCP1 AND CCP2)
Param Sym Characteristic
No.
Min
Typ† Max Units Conditions
50*
TccL CCP1 and CCP2 No Prescaler
input low time
0.5TCY + 20
—
—
ns
PIC16C73A/74A
PIC16LC73A/74A
10
—
—
—
—
—
—
—
—
ns
ns
ns
ns
With Prescaler
20
0.5TCY + 20
10
51*
TccH
No Prescaler
CCP1 and CCP2
input high time
PIC16C73A/74A
PIC16LC73A/74A
With Prescaler
20
—
—
—
—
ns
52*
53*
TccP
3TCY + 40
N
ns N = prescale
value (1,4 or 16)
CCP1 and CCP2 input period
TccR CCP1 and CCP2 output rise time
TccF CCP1 and CCP2 output fall time
—
10
25
ns
PIC16C73A/74A
PIC16LC73A/74A
—
—
25
10
45
25
ns
ns
54*
PIC16C73A/74A
PIC16LC73A/74A
—
25
45
ns
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated.
These parameters are for design guidance only and are not tested.
1997 Microchip Technology Inc.
DS30390E-page 211
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-8: PARALLEL SLAVE PORT TIMING (PIC16C74A)
RE2/CS
RE0/RD
RE1/WR
65
RD7:RD0
62
64
63
Note: Refer to Figure 19-1 for load conditions
TABLE 19-7: PARALLEL SLAVE PORT REQUIREMENTS (PIC16C74A)
Parameter
No.
Sym
Characteristic
Min Typ† Max Units Conditions
62
TdtV2wrH Data in valid before WR↑ or CS↑ (setup time)
20
25
—
—
—
—
ns
ns Extended
Range Only
63*
64
TwrH2dtI WR↑ or CS↑ to data–in invalid (hold time) PIC16C74A
PIC16LC74A
20
35
—
—
—
—
ns
ns
TrdL2dtV RD↓ and CS↓ to data–out valid
—
—
—
—
80
90
ns
ns Extended
Range Only
65
TrdH2dtI RD↑ or CS↓ to data–out invalid
10
—
30
ns
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 212
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-9: SPI MODE TIMING
SS
70
SCK
(CKP = 0)
71
72
78
79
79
78
SCK
(CKP = 1)
80
SDO
77
75, 76
SDI
74
73
Note: Refer to Figure 19-1 for load conditions
TABLE 19-8: SPI MODE REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max
Units
Conditions
70
TssL2scH,
TssL2scL
SS↓ to SCK↓ or SCK↑ input
TCY
—
—
ns
71
72
73
TscH
TscL
SCK input high time (slave mode)
SCK input low time (slave mode)
TCY + 20
TCY + 20
100
—
—
—
—
—
—
ns
ns
ns
TdiV2scH,
TdiV2scL
Setup time of SDI data input to SCK
edge
74
TscH2diL,
TscL2diL
Hold time of SDI data input to SCK
edge
100
—
—
ns
75
76
77
78
79
80
TdoR
SDO data output rise time
—
—
10
—
—
—
10
10
—
10
10
—
25
25
50
25
25
50
ns
ns
ns
ns
ns
ns
TdoF
SDO data output fall time
TssH2doZ
TscR
SS↑ to SDO output hi-impedance
SCK output rise time (master mode)
SCK output fall time (master mode)
TscF
TscH2doV,
TscL2doV
SDO data output valid after SCK
edge
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 213
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 19-10: I C BUS START/STOP BITS TIMING
SCL
93
91
90
92
SDA
STOP
Condition
START
Condition
Note: Refer to Figure 19-1 for load conditions
2
TABLE 19-9: I C BUS START/STOP BITS REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min Typ Max Units
Conditions
90
91
92
93
TSU:STA START condition
Setup time
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
4700
600
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Only relevant for repeated START
condition
ns
ns
ns
ns
THD:STA START condition
Hold time
4000
600
After this period the first clock
pulse is generated
TSU:STO STOP condition
Setup time
4700
600
THD:STO STOP condition
Hold time
4000
600
DS30390E-page 214
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 19-11: I C BUS DATA TIMING
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
Note: Refer to Figure 19-1 for load conditions
2
TABLE 19-10: I C BUS DATA REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Max
Units
Conditions
100
THIGH
Clock high time
100 kHz mode
400 kHz mode
4.0
0.6
—
—
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
4.7
—
—
101
TLOW
Clock low time
100 kHz mode
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
400 kHz mode
1.3
—
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
—
—
102
103
TR
TF
SDA and SCL rise
time
100 kHz mode
400 kHz mode
1000
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
SDA and SCL fall time 100 kHz mode
400 kHz mode
—
300
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
90
91
TSU:STA START condition
setup time
100 kHz mode
400 kHz mode
4.7
0.6
4.0
0.6
0
—
—
µs
µs
µs
µs
ns
µs
ns
ns
µs
µs
ns
ns
µs
µs
Only relevant for repeated
START condition
THD:STA START condition hold 100 kHz mode
—
After this period the first clock
pulse is generated
time
400 kHz mode
100 kHz mode
400 kHz mode
—
106
107
92
THD:DAT Data input hold time
—
0
0.9
—
TSU:DAT Data input setup time 100 kHz mode
400 kHz mode
250
100
4.7
0.6
—
Note 2
—
TSU:STO STOP condition setup 100 kHz mode
—
time
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
—
109
110
TAA
Output valid from
clock
3500
—
Note 1
—
TBUF
Bus free time
4.7
1.3
—
Time the bus must be free
before a new transmission can
start
—
Cb
Bus capacitive loading
—
400
pF
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of
the falling edge of SCL to avoid unintended generation of START or STOP conditions.
2
2
2: A fast-mode (400 kHz) I C-bus device can be used in a standard-mode (100 kHz) I C-bus system, but the requirement
tsu;DAT ≥ 250 ns must then be met.This will automatically be the case if the device does not stretch the LOW period of the
SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line
2
TR max.+tsu;DAT = 1000 + 250 = 1250 ns (according to the standard-mode I C bus specification) before the SCL line is
released.
1997 Microchip Technology Inc.
DS30390E-page 215
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-12: USART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
RC6/TX/CK
121
pin
121
RC7/RX/DT
pin
120
122
Note: Refer to Figure 19-1 for load conditions
TABLE 19-11: USART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Param Sym
No.
Characteristic
Min
Typ† Max Units Conditions
120
TckH2dtV
SYNC XMIT (MASTER &
SLAVE)
Clock high to data out valid
PIC16C73A/74A
PIC16LC73A/74A
—
—
—
—
—
—
—
—
—
—
—
—
80
100
45
ns
ns
ns
ns
ns
ns
121
122
Tckrf
Tdtrf
Clock out rise time and fall time PIC16C73A/74A
(Master Mode)
PIC16LC73A/74A
50
Data out rise time and fall time PIC16C73A/74A
PIC16LC73A/74A
45
50
†:
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
FIGURE 19-13: USART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
RC6/TX/CK
125
pin
RC7/RX/DT
pin
126
Note: Refer to Figure 19-1 for load conditions
TABLE 19-12: USART SYNCHRONOUS RECEIVE REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max
Units Conditions
125
TdtV2ckL
SYNC RCV (MASTER & SLAVE)
Data setup before CK ↓ (DT setup time)
15
15
—
—
—
—
ns
ns
126
TckL2dtl
Data hold after CK ↓ (DT hold time)
†:
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 216
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
TABLE 19-13: A/D CONVERTER CHARACTERISTICS:
PIC16C73A/74A-04 (Commercial, Industrial, Extended)
PIC16C73A/74A-10 (Commercial, Industrial, Extended)
PIC16C73A/74A-20 (Commercial, Industrial, Extended)
PIC16LC73A/74A-04 (Commercial, Industrial)
Param Sym Characteristic
No.
Min
Typ†
Max
Units
Conditions
A01
NR Resolution
—
—
—
—
—
—
—
—
—
—
—
—
8-bits
bit VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A02 EABS Total Absolute error
< ± 1
< ± 1
< ± 1
< ± 1
< ± 1
LSb
LSb
LSb
LSb
LSb
A03
A04
A05
EIL Integral linearity error
EDL Differential linearity error
EFS Full scale error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A06 EOFF Offset error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A10
—
Monotonicity
—
3.0V
guaranteed
—
—
V
VSS ≤ VAIN ≤ VREF
A20 VREF Reference voltage
—
—
—
VDD + 0.3
VREF + 0.3
10.0
A25
A30
VAIN Analog input voltage
VSS - 0.3
—
V
ZAIN Recommended impedance of
analog voltage source
kΩ
A40
A50
IAD A/D conversion current PIC16C73A/74A
—
—
180
90
—
—
µA Average current consump-
(VDD)
tion when A/D is on.
(Note 1)
PIC16LC73A/74A
µA
IREF VREF input current (Note 2)
10
—
1000
µA During VAIN acquisition.
Based on differential of
VHOLD to VAIN to charge
CHOLD, see Section 13.1.
—
—
10
µA During A/D Conversion
cycle
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: When A/D is off, it will not consume any current other than minor leakage current.
The power-down current spec includes any such leakage from the A/D module.
2: VREF current is from RA3 pin or VDD pin, whichever is selected as reference input.
1997 Microchip Technology Inc.
DS30390E-page 217
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 19-14: A/D CONVERSION TIMING
BSF ADCON0, GO
1 TCY
134
(TOSC/2) (1)
131
130
Q4
132
A/D CLK
7
6
5
4
3
2
1
0
A/D DATA
NEW_DATA
DONE
OLD_DATA
ADRES
ADIF
GO
SAMPLING STOPPED
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the
SLEEPinstruction to be executed.
TABLE 19-14: A/D CONVERSION REQUIREMENTS
Param Sym Characteristic
No.
Min
Typ†
Max
Units
Conditions
130
TAD A/D clock period
PIC16C73A/74A
PIC16LC73A/74A
PIC16C73A/74A
PIC16LC73A/74A
1.6
2.0
2.0
3.0
—
—
—
—
—
µs
TOSC based, VREF ≥ 3.0V
µs TOSC based, VREF full range
µs A/D RC Mode
µs A/D RC Mode
TAD
4.0
6.0
9.5
6.0
9.0
—
131
132
TCNV Conversion time (not including S/H time)
(Note 1)
TACQ Acquisition time
Note 2
5*
20
—
—
—
µs
µs The minimum time is the amplifier
settling time. This may be used if
the "new" input voltage has not
changed by more than 1 LSb (i.e.,
20.0 mV @ 5.12V) from the last
sampled voltage (as stated on
CHOLD).
134
135
TGO Q4 to A/D clock start
—
TOSC/2 §
—
—
—
If the A/D clock source is selected
as RC, a time of TCY is added
before the A/D clock starts. This
allows the SLEEPinstruction to be
executed.
TSWC Switching from convert → sample time
1.5 §
—
TAD
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
§
This specification ensured by design.
Note 1: ADRES register may be read on the following TCY cycle.
2: See Section 13.1 for min conditions.
DS30390E-page 218
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
20.0 ELECTRICAL CHARACTERISTICS FOR PIC16C76/77
Absolute Maximum Ratings †
Ambient temperature under bias..................................................................................................................-55 to +125˚C
Storage temperature............................................................................................................................... -65˚C to +150˚C
Voltage on any pin with respect to VSS (except VDD, MCLR. and RA4)...........................................-0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ............................................................................................................ -0.3 to +7.5V
Voltage on MCLR with respect to VSS (Note 2) ................................................................................................. 0 to +14V
Voltage on RA4 with respect to Vss................................................................................................................... 0 to +14V
Total power dissipation (Note 1).................................................................................................................................1.0W
Maximum current out of VSS pin ............................................................................................................................300 mA
Maximum current into VDD pin...............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD) .....................................................................................................................±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD)..............................................................................................................±20 mA
Maximum output current sunk by any I/O pin...........................................................................................................25 mA
Maximum output current sourced by any I/O pin .....................................................................................................25 mA
Maximum current sunk by PORTA, PORTB, and PORTE (combined) (Note 3).....................................................200 mA
Maximum current sourced by PORTA, PORTB, and PORTE (combined) (Note 3) ...............................................200 mA
Maximum current sunk by PORTC and PORTD (combined) (Note 3)...................................................................200 mA
Maximum current sourced by PORTC and PORTD (combined) (Note 3)..............................................................200 mA
Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - ∑ IOH} + ∑ {(VDD - VOH) x IOH} + ∑(VOl x IOL)
Note 2: Voltage spikes below VSS at the MCLR pin, inducing currents greater than 80 mA, may cause latch-up.Thus,
a series resistor of 50-100Ω should be used when applying a “low” level to the MCLRpin rather than pulling
this pin directly to VSS.
Note 3: PORTD and PORTE are not implemented on the PIC16C76.
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
1997 Microchip Technology Inc.
DS30390E-page 219
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
TABLE 20-1: CROSS REFERENCE OF DEVICE SPECS FOR OSCILLATOR CONFIGURATIONS
AND FREQUENCIES OF OPERATION (COMMERCIAL DEVICES)
PIC16C76-04
PIC16C77-04
PIC16C76-10
PIC16C77-10
PIC16C76-20
PIC16C77-20
PIC16LC76-04
PIC16LC77-04
OSC
JW Devices
VDD: 4.0V to 6.0V
IDD: 5 mA max.
at 5.5V
IPD: 16 µA max.
at 4V
VDD: 4.5V to 5.5V
IDD: 2.7 mA typ.
at 5.5V
IPD: 1.5 µA typ.
at 4V
VDD: 4.5V to 5.5V
IDD: 2.7 mA typ.
at 5.5V
IPD: 1.5 µA typ.
at 4V
VDD: 4.0V to 6.0V
IDD: 5 mA max.
at 5.5V
IPD: 16 µA max.
at 4V
VDD: 2.5V to 6.0V
IDD: 3.8 mA max.
at 3.0V
IPD: 5 µA max. at 3V
Freq: 4 MHz max.
RC
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.0V to 6.0V
IDD: 5 mA max.
at 5.5V
IPD: 16 µA max.
at 4V
VDD: 4.5V to 5.5V
IDD: 2.7 mA typ.
at 5.5V
IPD: 1.5 µA typ.
at 4V
VDD: 4.5V to 5.5V
IDD: 2.7 mA typ.
at 5.5V
IPD: 1.5 µA typ.
at 4V
VDD: 4.0V to 6.0V
IDD: 5 mA max.
at 5.5V
IPD: 16 µA max.
at 4V
VDD: 2.5V to 6.0V
IDD: 3.8 mA max.
at 3.0V
IPD: 5 µA max. at 3V
Freq: 4 MHz max.
XT
HS
LP
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
Freq: 4 MHz max.
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
VDD: 4.5V to 5.5V
IDD: 13.5 mA typ.
at 5.5V
IDD: 10 mA max.
at 5.5V
IDD: 20 mA max.
at 5.5V
IDD: 20 mA max.
at 5.5V
Not recommended for
use in HS mode
IPD: 1.5 µA typ.
IPD: 1.5 µA typ.
IPD: 1.5 µA typ.
IPD: 1.5 µA typ.
at 4.5V
at 4.5V
at 4.5V
at 4.5V
Freq: 4 MHz max.
Freq: 10 MHz max.
Freq: 20 MHz max.
Freq: 20 MHz max.
VDD: 4.0V to 6.0V
IDD: 52.5 µA typ.
at 32 kHz, 4.0V Not recommended for Not recommended for
IPD: 0.9 µA typ.
at 4.0V
VDD: 2.5V to 6.0V
IDD: 48 µA max.
at 32 kHz, 3.0V
IPD: 5.0 µA max.
at 3.0V
VDD: 2.5V to 6.0V
IDD: 48 µA max.
at 32 kHz, 3.0V
IPD: 5.0 µA max.
at 3.0V
use in LP mode
use in LP mode
Freq: 200 kHz max.
Freq: 200 kHz max.
Freq: 200 kHz max.
The shaded sections indicate oscillator selections which are tested for functionality, but not for MIN/MAX specifications.
It is recommended that the user select the device type that ensures the specifications required.
DS30390E-page 220
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
20.1
DC Characteristics:
PIC16C76/77-04 (Commercial, Industrial, Extended)
PIC16C76/77-10 (Commercial, Industrial, Extended)
PIC16C76/77-20 (Commercial, Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40˚C ≤ TA ≤ +125˚C for extended,
DC CHARACTERISTICS
-40˚C
0˚C
≤ TA ≤ +85˚C for industrial and
≤ TA ≤ +70˚C for commercial
Param
No.
Characteristic
Sym
VDD
Min Typ† Max Units
Conditions
D001 Supply Voltage
D001A
4.0
4.5
-
-
6.0
5.5
V
V
XT, RC and LP osc configuration
HS osc configuration
D002* RAM Data Retention
Voltage (Note 1)
VDR
-
1.5
-
V
D003
VDD start voltage to
ensure internal Power-on
Reset signal
VPOR
-
VSS
-
V
See section on Power-on Reset for details
D004* VDD rise rate to ensure
internal Power-on Reset
signal
SVDD
0.05
-
-
V/ms See section on Power-on Reset for details
D005 Brown-out Reset Voltage BVDD
3.7
3.7
-
4.0 4.3
4.0 4.4
V
V
BODEN bit in configuration word enabled
Extended Range Only
D010 Supply Current (Note 2,5) IDD
2.7
5
mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 5.5V (Note 4)
D013
-
-
10
20
mA HS osc configuration
FOSC = 20 MHz, VDD = 5.5V
D015* Brown-out Reset Current ∆IBOR
350 425 µA BOR enabled VDD = 5.0V
(Note 6)
D020 Power-down Current
D021 (Note 3,5)
D021A
IPD
-
-
-
-
10.5 42 µA VDD = 4.0V, WDT enabled, -40°C to +85°C
1.5
1.5
2.5
16
19
19
µA VDD = 4.0V, WDT disabled, -0°C to +70°C
µA VDD = 4.0V, WDT disabled, -40°C to +85°C
µA VDD = 4.0V, WDT disabled, -40°C to +125°C
D021B
D023* Brown-out Reset Current ∆IBOR
-
350 425 µA BOR enabled VDD = 5.0V
(Note 6)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
6: The ∆ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
1997 Microchip Technology Inc.
DS30390E-page 221
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
20.2
DC Characteristics: PIC16LC76/77-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
DC CHARACTERISTICS
Operating temperature -40˚C
0˚C
Sym Min Typ† Max Units
≤ TA ≤ +85˚C for industrial and
≤ TA ≤ +70˚C for commercial
Param
No.
Characteristic
Conditions
D001
Supply Voltage
VDD
VDR
2.5
-
-
6.0
-
V
V
LP, XT, RC osc configuration (DC - 4 MHz)
D002* RAM Data Retention
Voltage (Note 1)
1.5
D003
VDD start voltage to
ensure internal Power-on
Reset signal
VPOR
SVDD
-
VSS
-
-
-
V
See section on Power-on Reset for details
D004* VDD rise rate to ensure
internal Power-on Reset
signal
0.05
V/ms See section on Power-on Reset for details
D005
D010
Brown-out Reset Voltage BVDD
Supply Current (Note 2,5) IDD
3.7
-
4.0
2.0
4.3
3.8
V
BODEN bit in configuration word enabled
mA XT, RC osc configuration
FOSC = 4 MHz, VDD = 3.0V (Note 4)
D010A
-
-
22.5 48
350 425
µA LP osc configuration
FOSC = 32 kHz, VDD = 3.0V, WDT disabled
D015* Brown-out Reset Current ∆IBOR
µA BOR enabled VDD = 5.0V
(Note 6)
D020
D021
D021A
Power-down Current
(Note 3,5)
IPD
-
-
-
7.5
0.9
0.9
30
5
5
µA VDD = 3.0V, WDT enabled, -40°C to +85°C
µA VDD = 3.0V, WDT disabled, 0°C to +70°C
µA VDD = 3.0V, WDT disabled, -40°C to +85°C
D023* Brown-out Reset Current ∆IBOR
-
350 425
µA BOR enabled VDD = 5.0V
(Note 6)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated.These parameters are for design guidance only
and are not tested.
Note 1: This is the limit to which VDD can be lowered without losing RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tristated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
4: For RC osc configuration, current through Rext is not included. The current through the resistor can be esti-
mated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: Timer1 oscillator (when enabled) adds approximately 20 µA to the specification. This value is from charac-
terization and is for design guidance only. This is not tested.
6: The ∆ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
DS30390E-page 222
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
20.3
DC Characteristics:
PIC16C76/77-04 (Commercial, Industrial, Extended)
PIC16C76/77-10 (Commercial, Industrial, Extended)
PIC16C76/77-20 (Commercial, Industrial, Extended)
PIC16LC76/77-04 (Commercial, Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +125˚C for extended,
-40˚C ≤ TA ≤ +85˚C for industrial and
DC CHARACTERISTICS
0˚C
≤ TA ≤ +70˚C for commercial
Operating voltage VDD range as described in DC spec Section 20.1 and
Section 20.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Input Low Voltage
I/O ports
VIL
D030
D030A
D031
D032
D033
with TTL buffer
VSS
VSS
VSS
VSS
VSS
-
-
-
-
-
0.15VDD
0.8V
0.2VDD
0.2VDD
0.3VDD
V
V
V
V
V
For entire VDD range
4.5V ≤ VDD ≤ 5.5V
with Schmitt Trigger buffer
MCLR, OSC1 (in RC mode)
OSC1 (in XT, HS and LP)
Input High Voltage
I/O ports
Note1
VIH
-
-
-
D040
D040A
with TTL buffer
2.0
0.25VDD
+ 0.8V
VDD
VDD
V
V
4.5V ≤ VDD ≤ 5.5V
For entire VDD range
D041
D042
with Schmitt Trigger buffer
MCLR
0.8VDD
0.8VDD
0.7VDD
0.9VDD
50
-
-
-
-
VDD
VDD
VDD
VDD
V
V
V
V
For entire VDD range
Note1
D042A OSC1 (XT, HS and LP)
D043
D070
OSC1 (in RC mode)
PORTB weak pull-up current
Input Leakage Current
(Notes 2, 3)
IPURB
IIL
250 400
µA VDD = 5V, VPIN = VSS
D060
I/O ports
-
-
±1
µA Vss ≤ VPIN ≤ VDD, Pin at hi-imped-
ance
D061
D063
MCLR, RA4/T0CKI
OSC1
-
-
-
-
±5
±5
µA Vss ≤ VPIN ≤ VDD
µA Vss ≤ VPIN ≤ VDD, XT, HS and LP osc
configuration
Output Low Voltage
D080
I/O ports
VOL
-
-
-
-
-
-
-
-
0.6
0.6
0.6
0.6
V
V
V
V
IOL = 8.5 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 7.0 mA, VDD = 4.5V,
-40°C to +125°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.2 mA, VDD = 4.5V,
-40°C to +125°C
D080A
D083
OSC2/CLKOUT (RC osc config)
D083A
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
1997 Microchip Technology Inc.
DS30390E-page 223
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40˚C ≤ TA ≤ +125˚C for extended,
-40˚C ≤ TA ≤ +85˚C for industrial and
DC CHARACTERISTICS
0˚C
≤ TA ≤ +70˚C for commercial
Operating voltage VDD range as described in DC spec Section 20.1 and
Section 20.2.
Param
No.
Characteristic
Sym
Min Typ Max Units
†
Conditions
Output High Voltage
D090
I/O ports (Note 3)
VOH VDD - 0.7 -
VDD - 0.7 -
-
-
V
V
V
V
V
IOH = -3.0 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -2.5 mA, VDD = 4.5V,
-40°C to +125°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.0 mA, VDD = 4.5V,
-40°C to +125°C
D090A
D092
OSC2/CLKOUT (RC osc config)
VDD - 0.7 -
-
D092A
VDD - 0.7 -
-
D150* Open-Drain High Voltage
Capacitive Loading Specs on
Output Pins
VOD
-
-
-
-
14
RA4 pin
D100
OSC2 pin
COSC2
15
pF In XT, HS and LP modes when exter-
nal clock is used to drive OSC1.
D101
D102
All I/O pins and OSC2 (in RC
CIO
CB
-
-
-
-
50
400
pF
pF
2
mode) SCL, SDA in I C mode
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the
PIC16C7X be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
DS30390E-page 224
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
20.4
Timing Parameter Symbology
The timing parameter symbols have been created following one of the following formats:
2
1. TppS2ppS
2. TppS
3. TCC:ST
4. Ts
(I C specifications only)
2
(I C specifications only)
T
F
Frequency
T
Time
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
CLKOUT
CS
osc
rd
OSC1
RD
ck
cs
di
rw
sc
ss
t0
RD or WR
SCK
SDI
do
dt
SDO
SS
Data in
I/O port
MCLR
T0CKI
T1CKI
WR
io
t1
mc
wr
Uppercase letters and their meanings:
S
F
H
I
Fall
P
R
V
Z
Period
High
Rise
Invalid (Hi-impedance)
Low
Valid
L
Hi-impedance
2
I C only
AA
output access
Bus free
High
Low
High
Low
BUF
2
TCC:ST (I C specifications only)
CC
HD
ST
DAT
STA
Hold
SU
Setup
DATA input hold
START condition
STO
STOP condition
FIGURE 20-1: LOAD CONDITIONS
Load condition 1
Load condition 2
VDD/2
RL
CL
CL
Pin
Pin
VSS
VSS
RL = 464Ω
CL = 50 pF for all pins except OSC2, but including PORTD and PORTE outputs as
ports
15 pF for OSC2 output
Note: PORTD and PORTE are not implemented on the PIC16C76.
1997 Microchip Technology Inc.
DS30390E-page 225
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
20.5
Timing Diagrams and Specifications
FIGURE 20-2: EXTERNAL CLOCK TIMING
Q4
Q1
1
Q2
Q3
Q4
4
Q1
OSC1
3
3
4
2
CLKOUT
TABLE 20-2: EXTERNAL CLOCK TIMING REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units Conditions
Fosc External CLKIN Frequency
DC
DC
DC
DC
DC
DC
0.1
—
—
—
—
—
—
—
4
4
MHz XT and RC osc mode
MHz HS osc mode (-04)
MHz HS osc mode (-10)
MHz HS osc mode (-20)
kHz LP osc mode
(Note 1)
10
20
200
4
Oscillator Frequency
(Note 1)
MHz RC osc mode
4
MHz XT osc mode
4
5
—
—
20
200
MHz HS osc mode
kHz LP osc mode
1
Tosc External CLKIN Period
250
250
100
50
—
—
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
µs
ns
ns
ns
ns
XT and RC osc mode
HS osc mode (-04)
HS osc mode (-10)
HS osc mode (-20)
LP osc mode
(Note 1)
—
—
5
—
Oscillator Period
(Note 1)
250
250
250
100
—
RC osc mode
10,000
250
250
XT osc mode
HS osc mode (-04)
HS osc mode (-10)
HS osc mode (-20)
50
5
—
—
250
—
ns
µs
ns
ns
µs
ns
ns
ns
ns
LP osc mode
TCY = 4/FOSC
XT oscillator
LP oscillator
HS oscillator
XT oscillator
LP oscillator
HS oscillator
2
3
TCY
Instruction Cycle Time (Note 1)
200
100
2.5
15
—
TCY
—
DC
—
TosL, External Clock in (OSC1) High or
TosH Low Time
—
—
—
—
4
TosR, External Clock in (OSC1) Rise or
TosF Fall Time
—
25
50
15
—
—
—
—
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are based on
characterization data for that particular oscillator type under standard operating conditions with the device executing code.
Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current con-
sumption. All devices are tested to operate at "min." values with an external clock applied to the OSC1/CLKIN pin.
When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices.
DS30390E-page 226
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-3: CLKOUT AND I/O TIMING
Q1
Q2
Q3
Q4
OSC1
11
10
CLKOUT
13
14
12
18
19
16
I/O Pin
(input)
15
17
I/O Pin
new value
old value
(output)
20, 21
Note: Refer to Figure 20-1 for load conditions.
TABLE 20-3: CLKOUT AND I/O TIMING REQUIREMENTS
Param Sym
No.
Characteristic
Min
Typ†
Max
Units Conditions
10*
11*
12*
13*
14*
15*
16*
17*
TosH2ckL OSC1↑ to CLKOUT↓
TosH2ckH OSC1↑ to CLKOUT↑
—
75
75
35
35
—
—
—
50
200
200
ns
ns
ns
ns
ns
ns
ns
ns
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
Note 1
—
TckR
TckF
CLKOUT rise time
CLKOUT fall time
—
100
—
100
TckL2ioV CLKOUT ↓ to Port out valid
TioV2ckH Port in valid before CLKOUT ↑
TckH2ioI Port in hold after CLKOUT ↑
—
0.5TCY + 20
—
TOSC + 200
0
—
TosH2ioV OSC1↑ (Q1 cycle) to
—
150
Port out valid
18*
TosH2ioI OSC1↑ (Q2 cycle) to
Port input invalid (I/O in
hold time)
PIC16C76/77
PIC16LC76/77
100
200
—
—
—
—
ns
ns
19*
20*
TioV2osH Port input valid to OSC1↑ (I/O in setup time)
0
—
—
10
—
10
—
—
—
—
40
80
40
80
—
—
ns
ns
ns
ns
ns
ns
ns
TioR
Port output rise time
Port output fall time
INT pin high or low time
PIC16C76/77
PIC16LC76/77
PIC16C76/77
PIC16LC76/77
—
21*
TioF
—
—
22††* Tinp
23††* Trbp
TCY
TCY
RB7:RB4 change INT high or low time
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance
only and are not tested.
†† These parameters are asynchronous events not related to any internal clock edges.
Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC.
1997 Microchip Technology Inc.
DS30390E-page 227
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Time-out
Internal
RESET
Watchdog
Timer
RESET
31
34
34
I/O Pins
Note: Refer to Figure 20-1 for load conditions.
FIGURE 20-5: BROWN-OUT RESET TIMING
BVDD
VDD
35
TABLE 20-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER,
AND BROWN-OUT RESET REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max Units
Conditions
30
TmcL MCLR Pulse Width (low)
2
7
—
—
µs VDD = 5V, -40˚C to +125˚C
31*
Twdt
Watchdog Timer Time-out Period
18
33
ms VDD = 5V, -40˚C to +125˚C
(No Prescaler)
32
33*
34
Tost
Oscillation Start-up Timer Period
—
28
—
1024TOSC
—
—
TOSC = OSC1 period
Tpwrt Power up Timer Period
72
—
132
2.1
ms VDD = 5V, -40˚C to +125˚C
TIOZ
I/O Hi-impedance from MCLR Low
µs
or Watchdog Timer Reset
35
TBOR
Brown-out Reset pulse width
100
—
—
µs
VDD ≤ BVDD (D005)
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 228
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-6: TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
RA4/T0CKI
41
40
42
RC0/T1OSO/T1CKI
46
45
47
48
TMR0 or
TMR1
Note: Refer to Figure 20-1 for load conditions.
TABLE 20-5: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Sym
Characteristic
Min
Typ† Max Units Conditions
40*
Tt0H
T0CKI High Pulse Width
No Prescaler
0.5TCY + 20
—
—
ns Must also meet
parameter 42
With Prescaler
No Prescaler
10
0.5TCY + 20
10
—
—
—
—
—
—
—
—
—
—
ns
41*
42*
Tt0L
Tt0P
T0CKI Low Pulse Width
T0CKI Period
ns Must also meet
parameter 42
With Prescaler
No Prescaler
With Prescaler
ns
ns
TCY + 40
Greater of:
20 or TCY + 40
ns N = prescale value
(2, 4, ..., 256)
N
0.5TCY + 20
15
45*
46*
47*
Tt1H
Tt1L
Tt1P
T1CKI High Time Synchronous, Prescaler = 1
—
—
—
—
—
—
ns Must also meet
parameter 47
Synchronous, PIC16C7X
ns
ns
Prescaler =
2,4,8
PIC16LC7X
25
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
—
—
—
—
ns
ns
50
T1CKI Low Time
Synchronous, Prescaler = 1
Synchronous, PIC16C7X
0.5TCY + 20
ns Must also meet
parameter 47
15
25
ns
ns
Prescaler =
2,4,8
PIC16LC7X
Asynchronous PIC16C7X
PIC16LC7X
30
—
—
—
—
—
—
ns
ns
50
T1CKI input period Synchronous PIC16C7X
Greater of:
30 OR TCY + 40
ns N = prescale value
(1, 2, 4, 8)
N
Greater of:
50 OR TCY + 40
N = prescale value
(1, 2, 4, 8)
PIC16LC7X
N
60
Asynchronous PIC16C7X
PIC16LC7X
—
—
—
—
—
ns
ns
100
DC
Ft1
Timer1 oscillator input frequency range
(oscillator enabled by setting bit T1OSCEN)
200
kHz
48
*
TCKEZtmr1 Delay from external clock edge to timer increment
2Tosc
—
7Tosc
—
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 229
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-7: CAPTURE/COMPARE/PWM TIMINGS (CCP1 AND CCP2)
RC1/T1OSI/CCP2
and RC2/CCP1
(Capture Mode)
50
51
52
RC1/T1OSI/CCP2
and RC2/CCP1
(Compare or PWM Mode)
53
Note: Refer to Figure 20-1 for load conditions.
54
TABLE 20-6: CAPTURE/COMPARE/PWM REQUIREMENTS (CCP1 AND CCP2)
Param Sym Characteristic
No.
Min
Typ† Max Units Conditions
50*
TccL CCP1 and CCP2 No Prescaler
input low time
0.5TCY + 20
—
—
ns
PIC16C76/77
10
—
—
—
—
—
—
—
—
ns
ns
ns
ns
With Prescaler
PIC16LC76/77
20
0.5TCY + 20
10
51*
TccH
No Prescaler
CCP1 and CCP2
input high time
PIC16C76/77
With Prescaler
PIC16LC76/77
20
—
—
—
—
ns
52*
53*
TccP
3TCY + 40
N
ns N = prescale
value (1,4 or 16)
CCP1 and CCP2 input period
TccR CCP1 and CCP2 output rise time
TccF CCP1 and CCP2 output fall time
—
10
25
ns
PIC16C76/77
PIC16LC76/77
—
—
25
10
45
25
ns
ns
54*
PIC16C76/77
PIC16LC76/77
—
25
45
ns
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated.
These parameters are for design guidance only and are not tested.
DS30390E-page 230
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-8: PARALLEL SLAVE PORT TIMING (PIC16C77)
RE2/CS
RE0/RD
RE1/WR
65
RD7:RD0
62
64
63
Note: Refer to Figure 20-1 for load conditions
TABLE 20-7: PARALLEL SLAVE PORT REQUIREMENTS (PIC16C77)
Parameter
No.
Sym
Characteristic
Min Typ† Max Units Conditions
62
TdtV2wrH Data in valid before WR↑ or CS↑ (setup time)
20
25
—
—
—
—
ns
ns
Extended
Range Only
63*
64
TwrH2dtI WR↑ or CS↑ to data–in invalid (hold time) PIC16C77
PIC16LC77
20
35
—
—
—
—
ns
ns
TrdL2dtV RD↓ and CS↓ to data–out valid
—
—
—
—
80
90
ns
ns
Extended
Range Only
65
TrdH2dtI RD↑ or CS↓ to data–out invalid
10
—
30
ns
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 231
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-9: SPI MASTER MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
71
72
78
79
79
SCK
(CKP = 1)
78
80
BIT6 - - - - - -1
MSB
LSB
SDO
SDI
75, 76
MSB IN
74
BIT6 - - - -1
LSB IN
73
Refer to Figure 20-1 for load conditions.
FIGURE 20-10: SPI MASTER MODE TIMING (CKE = 1)
SS
81
SCK
(CKP = 0)
71
72
79
78
73
SCK
(CKP = 1)
80
LSB
MSB
BIT6 - - - - - -1
BIT6 - - - -1
SDO
SDI
75, 76
MSB IN
74
LSB IN
Refer to Figure 20-1 for load conditions.
DS30390E-page 232
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-11: SPI SLAVE MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
83
71
72
78
79
79
SCK
(CKP = 1)
78
80
MSB
LSB
SDO
SDI
BIT6 - - - - - -1
77
75, 76
MSB IN
74
BIT6 - - - -1
LSB IN
73
Refer to Figure 20-1 for load conditions.
FIGURE 20-12: SPI SLAVE MODE TIMING (CKE = 1)
82
SS
70
SCK
83
(CKP = 0)
71
72
SCK
(CKP = 1)
80
MSB
BIT6 - - - - - -1
BIT6 - - - -1
LSB
SDO
SDI
75, 76
77
MSB IN
74
LSB IN
Refer to Figure 20-1 for load conditions.
1997 Microchip Technology Inc.
DS30390E-page 233
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
TABLE 20-8: SPI MODE REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max
Units
Conditions
70*
TssL2scH,
TssL2scL
SS↓ to SCK↓ or SCK↑ input
TCY
—
—
ns
71*
72*
73*
TscH
TscL
SCK input high time (slave mode)
SCK input low time (slave mode)
TCY + 20
TCY + 20
100
—
—
—
—
—
—
ns
ns
ns
TdiV2scH,
TdiV2scL
Setup time of SDI data input to SCK
edge
74*
TscH2diL,
TscL2diL
Hold time of SDI data input to SCK
edge
100
—
—
ns
75*
76*
77*
78*
79*
80*
TdoR
SDO data output rise time
—
—
10
—
—
—
10
10
—
10
10
—
25
25
50
25
25
50
ns
ns
ns
ns
ns
ns
TdoF
SDO data output fall time
TssH2doZ
TscR
SS↑ to SDO output hi-impedance
SCK output rise time (master mode)
SCK output fall time (master mode)
TscF
TscH2doV,
TscL2doV
SDO data output valid after SCK
edge
81*
82*
83*
TdoV2scH,
TdoV2scL
SDO data output setup to SCK
edge
TCY
—
—
—
—
—
50
—
ns
ns
ns
TssL2doV
SDO data output valid after SS↓
edge
TscH2ssH,
TscL2ssH
SS ↑ after SCK edge
1.5TCY + 40
*
These parameters are characterized but not tested.
†
Data in "Typ" column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS30390E-page 234
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 20-13: I C BUS START/STOP BITS TIMING
SCL
93
91
90
92
SDA
STOP
Condition
START
Condition
Note: Refer to Figure 20-1 for load conditions
2
TABLE 20-9: I C BUS START/STOP BITS REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min Typ Max Units
Conditions
90
91
92
93
TSU:STA START condition
Setup time
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
4700
600
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Only relevant for repeated START
condition
ns
ns
ns
ns
THD:STA START condition
Hold time
4000
600
After this period the first clock
pulse is generated
TSU:STO STOP condition
Setup time
4700
600
THD:STO STOP condition
Hold time
4000
600
1997 Microchip Technology Inc.
DS30390E-page 235
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
2
FIGURE 20-14: I C BUS DATA TIMING
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
Note: Refer to Figure 20-1 for load conditions
2
TABLE 20-10: I C BUS DATA REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Max
Units
Conditions
100
THIGH
Clock high time
100 kHz mode
400 kHz mode
4.0
0.6
—
—
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
4.7
—
—
101
TLOW
Clock low time
100 kHz mode
µs
µs
Device must operate at a mini-
mum of 1.5 MHz
400 kHz mode
1.3
—
Device must operate at a mini-
mum of 10 MHz
SSP Module
1.5TCY
—
—
102
103
TR
TF
SDA and SCL rise
time
100 kHz mode
400 kHz mode
1000
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
SDA and SCL fall time 100 kHz mode
400 kHz mode
—
300
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
90
91
TSU:STA START condition
setup time
100 kHz mode
400 kHz mode
4.7
0.6
4.0
0.6
0
—
—
µs
µs
µs
µs
ns
µs
ns
ns
µs
µs
ns
ns
µs
µs
Only relevant for repeated
START condition
THD:STA START condition hold 100 kHz mode
—
After this period the first clock
pulse is generated
time
400 kHz mode
100 kHz mode
400 kHz mode
—
106
107
92
THD:DAT Data input hold time
—
0
0.9
—
TSU:DAT Data input setup time 100 kHz mode
400 kHz mode
250
100
4.7
0.6
—
Note 2
—
TSU:STO STOP condition setup 100 kHz mode
—
time
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
—
109
110
TAA
Output valid from
clock
3500
—
Note 1
—
TBUF
Bus free time
4.7
1.3
—
Time the bus must be free
before a new transmission can
start
—
Cb
Bus capacitive loading
—
400
pF
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of
the falling edge of SCL to avoid unintended generation of START or STOP conditions.
2
2
2: A fast-mode (400 kHz) I C-bus device can be used in a standard-mode (100 kHz) I C-bus system, but the requirement
tsu;DAT ≥ 250 ns must then be met.This will automatically be the case if the device does not stretch the LOW period of the
SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line
2
TR max.+tsu;DAT = 1000 + 250 = 1250 ns (according to the standard-mode I C bus specification) before the SCL line is
released.
DS30390E-page 236
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-15: USART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
RC6/TX/CK
pin
121
121
RC7/RX/DT
pin
120
122
Note: Refer to Figure 20-1 for load conditions
TABLE 20-11: USART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Param Sym
No.
Characteristic
Min
Typ† Max Units Conditions
120
TckH2dtV
SYNC XMIT (MASTER &
SLAVE)
Clock high to data out valid
PIC16C76/77
—
—
—
—
—
—
—
—
—
—
—
—
80
100
45
ns
ns
ns
ns
ns
ns
PIC16LC76/77
121
122
Tckrf
Tdtrf
Clock out rise time and fall time PIC16C76/77
(Master Mode)
PIC16LC76/77
50
Data out rise time and fall time PIC16C76/77
PIC16LC76/77
45
50
†:
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
FIGURE 20-16: USART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
RC6/TX/CK
125
pin
RC7/RX/DT
pin
126
Note: Refer to Figure 20-1 for load conditions
TABLE 20-12: USART SYNCHRONOUS RECEIVE REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min
Typ†
Max
Units Conditions
125
TdtV2ckL
TckL2dtl
SYNC RCV (MASTER & SLAVE)
Data setup before CK ↓ (DT setup time)
15
15
—
—
—
—
ns
ns
126
Data hold after CK ↓ (DT hold time)
†:
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
1997 Microchip Technology Inc.
DS30390E-page 237
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
TABLE 20-13: A/D CONVERTER CHARACTERISTICS:
PIC16C76/77-04 (Commercial, Industrial, Extended)
PIC16C76/77-10 (Commercial, Industrial, Extended)
PIC16C76/77-20 (Commercial, Industrial, Extended)
PIC16LC76/77-04 (Commercial, Industrial)
Param Sym Characteristic
No.
Min
Typ†
Max
Units
Conditions
A01
NR Resolution
—
—
—
—
—
—
—
—
—
—
—
—
8-bits
bit VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A02 EABS Total Absolute error
< ± 1
< ± 1
< ± 1
< ± 1
< ± 1
LSb
LSb
LSb
LSb
LSb
A03
A04
A05
EIL Integral linearity error
EDL Differential linearity error
EFS Full scale error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A06 EOFF Offset error
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A10
—
Monotonicity
—
3.0V
guaranteed
—
—
V
VSS ≤ VAIN ≤ VREF
A20 VREF Reference voltage
—
—
—
VDD + 0.3
VREF + 0.3
10.0
A25
A30
VAIN Analog input voltage
VSS - 0.3
—
V
ZAIN Recommended impedance of
analog voltage source
kΩ
A40
A50
IAD A/D conversion current PIC16C76/77
—
—
180
90
—
—
µA Average current consump-
(VDD)
tion when A/D is on.
(Note 1)
PIC16LC76/77
µA
IREF VREF input current (Note 2)
10
—
1000
µA During VAIN acquisition.
Based on differential of
VHOLD to VAIN to charge
CHOLD, see Section 13.1.
—
—
10
µA During A/D Conversion
cycle
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
Note 1: When A/D is off, it will not consume any current other than minor leakage current.
The power-down current spec includes any such leakage from the A/D module.
2: VREF current is from RA3 pin or VDD pin, whichever is selected as reference input.
DS30390E-page 238
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 20-17: A/D CONVERSION TIMING
BSF ADCON0, GO
1 Tcy
(TOSC/2) (1)
134
131
Q4
130
132
A/D CLK
7
6
5
4
3
2
1
0
A/D DATA
NEW_DATA
DONE
OLD_DATA
ADRES
ADIF
GO
SAMPLING STOPPED
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the
SLEEPinstruction to be executed.
TABLE 20-14: A/D CONVERSION REQUIREMENTS
Param Sym Characteristic
No.
Min
Typ†
Max
Units
Conditions
130
TAD A/D clock period
PIC16C76/77
PIC16LC76/77
PIC16C76/77
PIC16LC76/77
1.6
2.0
2.0
3.0
—
—
—
—
—
µs
TOSC based, VREF ≥ 3.0V
µs TOSC based, VREF full range
µs A/D RC Mode
µs A/D RC Mode
TAD
4.0
6.0
9.5
6.0
9.0
—
131
132
TCNV Conversion time (not including S/H time)
(Note 1)
TACQ Acquisition time
Note 2
5*
20
—
—
—
µs
µs The minimum time is the amplifier
settling time. This may be used if
the "new" input voltage has not
changed by more than 1 LSb (i.e.,
20.0 mV @ 5.12V) from the last
sampled voltage (as stated on
CHOLD).
134
135
TGO Q4 to A/D clock start
—
TOSC/2 §
—
—
—
If the A/D clock source is selected
as RC, a time of TCY is added
before the A/D clock starts. This
allows the SLEEPinstruction to be
executed.
TSWC Switching from convert → sample time
1.5 §
—
TAD
*
These parameters are characterized but not tested.
†
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
§
This specification ensured by design.
Note 1: ADRES register may be read on the following TCY cycle.
2: See Section 13.1 for min conditions.
1997 Microchip Technology Inc.
DS30390E-page 239
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
NOTES:
DS30390E-page 240
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
21.0 DC AND AC CHARACTERISTICS GRAPHS AND TABLES
The graphs and tables provided in this section are for design guidance and are not tested or guaranteed.
In some graphs or tables the data presented are outside specified operating range (i.e., outside specified VDD
range). This is for information only and devices are guaranteed to operate properly only within the specified
range.
Note: The data presented in this section is a statistical summary of data collected on units from different lots over
a period of time and matrix samples. 'Typical' represents the mean of the distribution at, 25°C, while 'max'
or 'min' represents (mean +3σ) and (mean -3σ) respectively where σ is standard deviation.
FIGURE 21-1: TYPICAL IPD vs. VDD (WDT DISABLED, RC MODE)
35
30
25
20
15
10
5
0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
FIGURE 21-2: MAXIMUM IPD vs. VDD (WDT DISABLED, RC MODE)
10.000
85°C
70°C
1.000
0.100
25°C
0°C
-40°C
0.010
0.001
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
1997 Microchip Technology Inc.
DS30390E-page 241
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-3: TYPICAL IPD vs. VDD @ 25°C
FIGURE 21-5: TYPICAL RC OSCILLATOR
FREQUENCY vs. VDD
(WDT ENABLED, RC MODE)
Cext = 22 pF,T = 25°C
6.0
25
20
15
10
5
5.5
5.0
4.5
R = 5k
4.0
3.5
3.0
R = 10k
2.5
2.0
1.5
1.0
R = 100k
0
2.5
0.5
0.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
Shaded area is beyond recommended range.
FIGURE 21-4: MAXIMUM IPD vs. VDD (WDT
ENABLED, RC MODE)
FIGURE 21-6: TYPICAL RC OSCILLATOR
FREQUENCY vs. VDD
35
-40°C
Cext = 100 pF,T = 25°C
30
0°C
2.4
2.2
25
20
R = 3.3k
2.0
1.8
1.6
70°C
15
R = 5k
1.4
85°C
1.2
10
1.0
R = 10k
5
0
0.8
0.6
0.4
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
R = 100k
0.2
VDD(Volts)
0.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
FIGURE 21-7: TYPICAL RC OSCILLATOR
FREQUENCY vs. VDD
Cext = 300 pF,T = 25°C
1000
900
800
R = 3.3k
700
600
R = 5k
500
400
R = 10k
300
200
R = 100k
5.5 6.0
100
0
2.5
3.0
3.5
4.0
4.5
5.0
VDD(Volts)
DS30390E-page 242
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-8: TYPICAL IPD vs. VDD BROWN-
OUT DETECT ENABLED (RC
MODE)
FIGURE 21-10: TYPICAL IPD vs.TIMER1
ENABLED (32 kHz, RC0/RC1 =
33 pF/33 pF, RC MODE)
1400
1200
1000
30
25
20
15
10
5
Device NOT in
Brown-out Reset
800
600
400
200
0
Device in
Brown-out
Reset
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
The shaded region represents the built-in hysteresis of the
brown-out reset circuitry.
VDD(Volts)
FIGURE 21-9: MAXIMUM IPD vs. VDD
BROWN-OUT DETECT
ENABLED
FIGURE 21-11: MAXIMUM IPD vs.TIMER1
ENABLED
(32 kHz, RC0/RC1 = 33 pF/33
(85°C TO -40°C, RC MODE)
pF, 85°C TO -40°C, RC MODE)
1600
1400
1200
45
40
35
30
1000
Device NOT in
Brown-out Reset
800
600
400
200
0
Device in
Brown-out
Reset
25
20
15
10
5
4.3
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
0
The shaded region represents the built-in hysteresis of the
brown-out reset circuitry.
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
1997 Microchip Technology Inc.
DS30390E-page 243
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-12: TYPICAL IDD vs. FREQUENCY (RC MODE @ 22 pF, 25°C)
2000
1800
1600
1400
1200
1000
800
6.0V
5.5V
5.0V
4.5V
4.0V
3.5V
3.0V
2.5V
600
400
200
0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Frequency(MHz)
Shaded area is
beyond recommended range
FIGURE 21-13: MAXIMUM IDD vs. FREQUENCY (RC MODE @ 22 pF, -40°C TO 85°C)
2000
6.0V
1800
1600
1400
1200
1000
800
600
400
200
0
5.5V
5.0V
4.5V
4.0V
3.5V
3.0V
2.5V
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Frequency(MHz)
Shaded area is
beyond recommended range
DS30390E-page 244
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-14: TYPICAL IDD vs. FREQUENCY (RC MODE @ 100 pF, 25°C)
1600
1400
1200
1000
800
6.0V
5.5V
5.0V
4.5V
4.0V
3.5V
3.0V
2.5V
600
400
200
0
0
200
Shaded area is
beyond recommended range
400
600
800
1000
1200
1400
1600
1800
Frequency(kHz)
FIGURE 21-15: MAXIMUM IDD vs. FREQUENCY (RC MODE @ 100 pF, -40°C TO 85°C)
1600
6.0V
5.5V
1400
1200
1000
800
5.0V
4.5V
4.0V
3.5V
3.0V
2.5V
600
400
200
0
0
200
Shaded area is
beyond recommended range
400
600
800
1000
1200
1400
1600
1800
Frequency(kHz)
1997 Microchip Technology Inc.
DS30390E-page 245
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-16: TYPICAL IDD vs. FREQUENCY (RC MODE @ 300 pF, 25°C)
1200
1000
800
600
400
200
0
6.0V
5.5V
5.0V
4.5V
4.0V
3.5V
3.0V
2.5V
0
100
200
300
400
500
600
700
Frequency(kHz)
FIGURE 21-17: MAXIMUM IDD vs. FREQUENCY (RC MODE @ 300 pF, -40°C TO 85°C)
1200
6.0V
5.5V
1000
800
600
400
200
0
5.0V
4.5V
4.0V
3.5V
3.0V
2.5V
0
100
200
300
400
500
600
700
Frequency(kHz)
DS30390E-page 246
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-18: TYPICAL IDD vs.
CAPACITANCE @ 500 kHz
FIGURE 21-19: TRANSCONDUCTANCE(gm)
OF HS OSCILLATOR vs. VDD
(RC MODE)
600
500
400
300
200
100
4.0
Max -40°C
5.0V
3.5
3.0
4.0V
3.0V
2.5
Typ 25°C
2.0
Min 85°C
1.5
1.0
0.5
0.0
0
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
20 pF
100 pF
300 pF
VDD(Volts)
Capacitance(pF)
Shaded area is
beyond recommended range
TABLE 21-1: RC OSCILLATOR
FREQUENCIES
FIGURE 21-20: TRANSCONDUCTANCE(gm)
OF LP OSCILLATOR vs. VDD
Average
110
Cext
Rext
100
Max -40°C
Fosc @ 5V, 25°C
90
80
70
22 pF
5k
10k
100k
3.3k
5k
4.12 MHz
2.35 MHz
268 kHz
1.80 MHz
1.27 MHz
688 kHz
77.2 kHz
707 kHz
501 kHz
269 kHz
28.3 kHz
± 1.4%
± 1.4%
60
50
40
30
20
10
0
Typ 25°C
± 1.1%
± 1.0%
± 1.0%
± 1.2%
± 1.0%
± 1.4%
± 1.2%
± 1.6%
± 1.1%
100 pF
300 pF
10k
100k
3.3k
5k
Min 85°C
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0
VDD(Volts)
Shaded areas are
beyond recommended range
10k
100k
FIGURE 21-21: TRANSCONDUCTANCE(gm)
OF XT OSCILLATOR vs. VDD
The percentage variation indicated here is part to
part variation due to normal process distribution.The
variation indicated is ±3 standard deviation from
average value for VDD = 5V.
1000
900
Max -40°C
800
700
600
500
400
300
200
100
0
Typ 25°C
Min 85°C
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0
VDD(Volts)
Shaded areas are
beyond recommended range
1997 Microchip Technology Inc.
DS30390E-page 247
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-22: TYPICAL XTAL STARTUP
FIGURE 21-24: TYPICAL XTAL STARTUP
TIME vs. VDD (LP MODE, 25°C)
TIME vs. VDD (XT MODE, 25°C)
3.5
3.0
2.5
70
60
50
2.0
40
200 kHz, 68 pF/68 pF
32 kHz, 33 pF/33 pF
1.5
30
200 kHz, 47 pF/47 pF
20
1.0
1 MHz, 15 pF/15 pF
10
4 MHz, 15 pF/15 pF
0.5
0.0
200 kHz, 15 pF/15 pF
0
2.5
3.0
3.5
4.0
VDD(Volts)
4.5
5.0
5.5
6.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
FIGURE 21-23: TYPICAL XTAL STARTUP
TABLE 21-2: CAPACITOR SELECTION
FOR CRYSTAL
TIMEvs.VDD (HSMODE,25°C)
OSCILLATORS
Crystal
Freq
Cap. Range
C1
Cap. Range
C2
7
6
5
4
3
2
1
Osc Type
LP
32 kHz
200 kHz
200 kHz
1 MHz
33 pF
15 pF
33 pF
15 pF
20 MHz, 33 pF/33 pF
XT
HS
47-68 pF
15 pF
47-68 pF
15 pF
8 MHz, 33 pF/33 pF
4 MHz
15 pF
15 pF
20 MHz, 15 pF/15 pF
8 MHz, 15 pF/15 pF
4 MHz
15 pF
15 pF
8 MHz
15-33 pF
15-33 pF
15-33 pF
15-33 pF
20 MHz
4.0
4.5
5.0
5.5
6.0
VDD(Volts)
Crystals
Used
32 kHz
200 kHz
1 MHz
Epson C-001R32.768K-A
STD XTL 200.000KHz
ECS ECS-10-13-1
± 20 PPM
± 20 PPM
± 50 PPM
± 50 PPM
± 30 PPM
± 30 PPM
4 MHz
ECS ECS-40-20-1
8 MHz
EPSON CA-301 8.000M-C
EPSON CA-301 20.000M-C
20 MHz
DS30390E-page 248
1997 Microchip Technology Inc.
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-25: TYPICAL IDD vs. FREQUENCY
FIGURE 21-27: TYPICAL IDD vs. FREQUENCY
(LP MODE, 25°C)
(XT MODE, 25°C)
1800
1600
6.0V
120
100
80
5.5V
1400
5.0V
1200
4.5V
1000
800
600
4.0V
3.5V
60
6.0V
5.5V
5.0V
4.5V
4.0V
3.5V
40
20
0
3.0V
2.5V
3.0V
2.5V
400
200
0
50
100
150
200
Frequency(kHz)
0
0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 3.6 4.0
Frequency(MHz)
FIGURE 21-26: MAXIMUM IDD vs.
FREQUENCY
FIGURE 21-28: MAXIMUM IDD vs.
FREQUENCY
(LP MODE, 85°C TO -40°C)
(XT MODE, -40°C TO 85°C)
1800
1600
1400
1200
6.0V
5.5V
5.0V
4.5V
140
120
100
80
4.0V
1000
3.5V
6.0V
5.5V
5.0V
4.5V
4.0V
3.5V
60
800
600
3.0V
40
2.5V
20
400
200
3.0V
2.5V
0
0
50
100
150
200
0
Frequency(kHz)
0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 3.6 4.0
Frequency(MHz)
1997 Microchip Technology Inc.
DS30390E-page 249
PIC16C7X
Applicable Devices 72 73 73A 74 74A 76 77
FIGURE 21-29: TYPICAL IDD vs. FREQUENCY
FIGURE 21-30: MAXIMUM IDD vs.
FREQUENCY
(HS MODE, 25°C)
(HS MODE, -40°C TO 85°C)
7.0
6.0
5.0
4.0
3.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0.0
6.0V
2.0
5.5V
5.0V
4.5V
4.0V
6.0V
5.5V
5.0V
4.5V
4.0V
1.0
0.0
1
2
4
6
8
10
12
14
16
18
20
1
2
4
6
8
10
12
14
16
18
20
Frequency(MHz)
Frequency(MHz)
DS30390E-page 250
1997 Microchip Technology Inc.
PIC16C7X
22.0 PACKAGING INFORMATION
22.1
28-Lead Ceramic Side Brazed Dual In-Line with Window (300 mil)(JW)
N
C
E1 E
eA
eB
α
Pin #1
Indicator Area
D
S1
S
Base
Plane
Seating
Plane
A3
A2
A
L
A1
B1
e1
B
D1
Package Group: Ceramic Side Brazed Dual In-Line (CER)
Millimeters
Max
Inches
Max
Symbol
Min
Notes
Min
Notes
α
0°
10°
5.030
1.524
3.506
2.388
0.508
1.321
0.305
35.916
33.147
8.128
7.620
2.667
7.874
8.179
4.064
28
0°
10°
A
3.937
1.016
2.921
1.930
0.406
1.219
0.228
35.204
32.893
7.620
7.366
2.413
7.366
7.594
3.302
28
0.155
0.040
0.115
0.076
0.016
0.048
0.009
1.386
1.295
0.300
0.290
0.095
0.290
0.299
0.130
28
0.198
0.060
0.138
0.094
0.020
0.052
0.012
1.414
1.305
0.320
0.300
0.105
0.310
0.322
0.160
28
A1
A2
A3
B
B1
C
Typical
Typical
D
D1
E
Reference
E1
e1
eA
eB
L
Typical
Reference
N
S
1.143
0.533
1.397
0.737
0.045
0.021
0.055
0.029
S1
1997 Microchip Technology Inc.
DS30390E-page 251
PIC16C7X
22.2
40-Lead Ceramic CERDIP Dual In-line with Window (600 mil) (JW)
N
E1
E
α
C
Pin No. 1
Indicator
Area
eA
eB
D
S
S1
e1
Base
Plane
Seating
Plane
L
B1
B
A
A3
A2
A1
D1
Package Group: Ceramic CERDIP Dual In-Line (CDP)
Millimeters
Inches
Max
Symbol
Min
Max
Notes
Min
Notes
α
0°
10°
0°
10°
A
4.318
0.381
3.810
3.810
0.355
1.270
0.203
5.715
1.778
4.699
4.445
0.585
1.651
0.381
52.705
48.260
15.875
15.240
2.540
16.002
18.034
3.810
40
0.170
0.015
0.150
0.150
0.014
0.050
0.008
2.025
1.900
0.600
0.510
0.100
0.590
0.600
0.125
40
0.225
0.070
0.185
0.175
0.023
0.065
0.015
2.075
1.900
0.625
0.600
0.100
0.630
0.710
0.150
40
A1
A2
A3
B
B1
C
Typical
Typical
Typical
Typical
D
51.435
48.260
15.240
12.954
2.540
14.986
15.240
3.175
40
D1
E
Reference
Reference
E1
e1
eA
eB
L
Reference
Typical
Reference
Typical
N
S
1.016
0.381
2.286
1.778
0.040
0.015
0.090
0.070
S1
DS30390E-page 252
1997 Microchip Technology Inc.
PIC16C7X
22.3
28-Lead Plastic Dual In-line (300 mil) (SP)
N
α
E1
E
C
eA
eB
Pin No. 1
Indicator
Area
B2
B1
D
S
Base
Plane
Seating
Plane
L
Detail A
B
Detail A
B3
A
A2
A1
e1
D1
Package Group: Plastic Dual In-Line (PLA)
Millimeters
Inches
Max
Symbol
Min
Max
Notes
Min
Notes
α
0°
10°
4.572
–
0°
10°
A
3.632
0.381
3.175
0.406
1.016
0.762
0.203
0.203
0.143
0.015
0.125
0.016
0.040
0.030
0.008
0.008
1.385
1.300
0.310
0.280
0.100
0.310
0.320
0.125
28
0.180
–
A1
A2
B
3.556
0.559
1.651
1.016
0.508
0.331
35.179
33.020
8.382
7.493
2.540
7.874
9.652
3.683
-
0.140
0.022
0.065
0.040
0.020
0.013
1.395
1.300
0.330
0.295
0.100
0.310
0.380
0.145
-
B1
B2
B3
C
Typical
4 places
4 places
Typical
Typical
4 places
4 places
Typical
D
34.163
33.020
7.874
7.112
2.540
7.874
8.128
3.175
28
D1
E
Reference
Reference
E1
e1
eA
eB
L
Typical
Typical
Reference
Reference
N
S
0.584
1.220
0.023
0.048
1997 Microchip Technology Inc.
DS30390E-page 253
PIC16C7X
22.4
40-Lead Plastic Dual In-line (600 mil) (P)
N
α
E1
E
C
eA
eB
Pin No. 1
Indicator
Area
D
S
S1
e1
Base
Plane
Seating
Plane
L
B1
B
A
A2
A1
D1
Package Group: Plastic Dual In-Line (PLA)
Millimeters
Inches
Symbol
Min
Max
Notes
Min
Max
Notes
α
0°
10°
5.080
–
0°
10°
0.200
–
A
–
–
A1
A2
B
0.381
3.175
0.355
1.270
0.203
0.015
0.125
0.014
0.050
0.008
2.015
1.900
0.600
0.530
0.098
0.600
0.600
0.115
40
4.064
0.559
1.778
0.381
52.197
48.260
15.875
13.970
2.591
15.240
17.272
3.683
40
0.160
0.022
0.070
0.015
2.055
1.900
0.625
0.550
0.102
0.600
0.680
0.145
40
B1
C
Typical
Typical
Typical
Typical
D
51.181
48.260
15.240
13.462
2.489
15.240
15.240
2.921
40
D1
E
Reference
Reference
E1
e1
eA
eB
L
Typical
Typical
Reference
Reference
N
S
1.270
0.508
–
0.050
0.020
–
S1
–
–
DS30390E-page 254
1997 Microchip Technology Inc.
PIC16C7X
22.5
28-Lead Plastic Surface Mount (SOIC - Wide, 300 mil Body) (SO)
e
B
h x 45°
N
Index
Area
E
H
α
C
Chamfer
h x 45°
L
1
2
3
D
Base
Plane
CP
Seating
Plane
A1
A
Package Group: Plastic SOIC (SO)
Millimeters
Max
Inches
Symbol
Min
0°
Notes
Min
Max
Notes
α
A
8°
0°
8°
2.362
0.101
0.355
0.241
17.703
7.416
1.270
10.007
0.381
0.406
28
2.642
0.300
0.483
0.318
18.085
7.595
1.270
10.643
0.762
1.143
28
0.093
0.004
0.014
0.009
0.697
0.292
0.050
0.394
0.015
0.016
28
0.104
0.012
0.019
0.013
0.712
0.299
0.050
0.419
0.030
0.045
28
A1
B
C
D
E
e
Typical
Typical
H
h
L
N
CP
–
0.102
–
0.004
1997 Microchip Technology Inc.
DS30390E-page 255
PIC16C7X
22.6
28-Lead Plastic Surface Mount (SSOP - 209 mil Body 5.30 mm) (SS)
N
Index
area
E
H
α
C
L
1 2 3
e
B
A
Base plane
CP
Seating plane
D
A1
Package Group: Plastic SSOP
Millimeters
Max
Inches
Max
Symbol
Min
Notes
Min
Notes
α
A
0°
8°
0°
8°
1.730
0.050
0.250
0.130
10.070
5.200
0.650
7.650
0.550
28
1.990
0.210
0.380
0.220
10.330
5.380
0.650
7.900
0.950
28
0.068
0.002
0.010
0.005
0.396
0.205
0.026
0.301
0.022
28
0.078
0.008
0.015
0.009
0.407
0.212
0.026
0.311
0.037
28
A1
B
C
D
E
e
Reference
Reference
H
L
N
CP
-
0.102
-
0.004
DS30390E-page 256
1997 Microchip Technology Inc.
PIC16C7X
22.7
44-Lead Plastic Leaded Chip Carrier (Square)(PLCC)
D
0.812/0.661
N Pics
.032/.026
1.27
.050
2 Sides
0.177
.007
S
B D-E S
-A-
0.177
.007
2 Sides
-H-
B A S
9
S
A
D1
A1
-D-
3
D3/E3
D2
0.101
.004
Seating
Plane
D
0.38
.015
-C-
F-G
E2
S
S
3
-G-
4
4
3
-F-
8
E1
E
0.38
.015
F-G
-B-
-E-
3
0.177
.007
A F-G S
S
10
0.812/0.661
.032/.026
3
0.254
.010
0.254
.010
11
Max
Max
11
1.524
.060
0.508
.020
0.508
.020
Min
-H-
2
-H-
2
6
6
-C-
5
1.651
.065
1.651
.065
0.64
.025
0.533/0.331
.021/.013
Min
R
R
1.14/0.64
.045/.025
1.14/0.64
.045/.025
0.177
.007
D-E S
F-G S ,
A
M
Package Group: Plastic Leaded Chip Carrier (PLCC)
Millimeters
Inches
Max
Symbol
Min
Max
Notes
Min
Notes
A
A1
D
4.191
2.413
17.399
16.510
15.494
12.700
17.399
16.510
15.494
12.700
44
4.572
2.921
0.165
0.095
0.685
0.650
0.610
0.500
0.685
0.650
0.610
0.500
44
0.180
0.115
0.695
0.656
0.630
0.500
0.695
0.656
0.630
0.500
44
17.653
16.663
16.002
12.700
17.653
16.663
16.002
12.700
44
D1
D2
D3
E
Reference
Reference
Reference
Reference
E1
E2
E3
N
CP
LT
–
0.102
–
0.004
0.015
0.203
0.381
0.008
1997 Microchip Technology Inc.
DS30390E-page 257
PIC16C7X
22.8
44-Lead Plastic Surface Mount (MQFP 10x10 mm Body 1.6/0.15 mm Lead Form) (PQ)
0.20 M C A-B S D S
D
4
5
0.20 M H A-B S D S
0.05 mm/mm A-B
D1
7
0.20 min.
D3
0.13 R min.
Index
area
6
PARTING
LINE
0.13/0.30 R
b
α
9
L
C
E3
E1
E
1.60 Ref.
0.20 M C A-B S D S
4
TYP 4x
10
0.20 M H A-B S D S
5
7
e
B
0.05 mm/mm D
A2
A
Base
Plane
Seating
Plane
A1
Package Group: Plastic MQFP
Millimeters
Max
Inches
Max
Symbol
Min
Notes
Min
Notes
α
A
0°
7°
0°
7°
2.000
0.050
1.950
0.300
0.150
12.950
9.900
8.000
12.950
9.900
8.000
0.800
0.730
44
2.350
0.250
2.100
0.450
0.180
13.450
10.100
8.000
13.450
10.100
8.000
0.800
1.030
44
0.078
0.002
0.768
0.011
0.006
0.510
0.390
0.315
0.510
0.390
0.315
0.031
0.028
44
0.093
0.010
0.083
0.018
0.007
0.530
0.398
0.315
0.530
0.398
0.315
0.032
0.041
44
A1
A2
b
Typical
Typical
C
D
D1
D3
E
Reference
Reference
Reference
Reference
E1
E3
e
L
N
CP
0.102
–
0.004
–
DS30390E-page 258
1997 Microchip Technology Inc.
PIC16C7X
22.9
44-Lead Plastic Surface Mount (TQFP 10x10 mm Body 1.0/0.10 mm Lead Form) (TQ)
D
D1
1.0ø (0.039ø) Ref.
11°/13°(4x)
0° Min
Pin#1
2
Pin#1
2
E
E1
Θ
11°/13°(4x)
Detail B
e
3.0ø (0.118ø) Ref.
R1 0.08 Min
R 0.08/0.20
Option 1 (TOP side)
Option 2 (TOP side)
Gage Plane
0.250
A1
Base Metal
Lead Finish
b
A2
A
S
0.20
Min
L
L
c
c1
L1
Detail A
Detail B
1.00 Ref
1.00 Ref.
b1
Detail A
Detail B
Package Group: Plastic TQFP
Millimeters
Max
Inches
Max
Symbol
Min
Notes
Min
Notes
A
A1
A2
D
1.00
0.05
0.95
11.75
9.90
11.75
9.90
0.45
1.20
0.15
0.039
0.002
0.037
0.463
0.390
0.463
0.390
0.018
0.047
0.006
0.041
0.482
0.398
0.482
0.398
0.030
1.05
12.25
10.10
12.25
10.10
0.75
D1
E
E1
L
e
0.80 BSC
0.031 BSC
b
0.30
0.30
0.09
0.09
44
0.45
0.40
0.20
0.16
44
0.012
0.012
0.004
0.004
44
0.018
0.016
0.008
0.006
44
b1
c
c1
N
Θ
0°
7°
0°
7°
Note 1: Dimensions D1 and E1 do not include mold protrusion. Allowable mold protrusion is 0.25m/m (0.010”) per
side. D1 and E1 dimensions including mold mismatch.
2: Dimension “b” does not include Dambar protrusion, allowable Dambar protrusion shall be 0.08m/m
(0.003”)max.
3: This outline conforms to JEDEC MS-026.
1997 Microchip Technology Inc.
DS30390E-page 259
PIC16C7X
22.10 Package Marking Information
28-Lead SSOP
Example
XXXXXXXXXXXX
XXXXXXXXXXXX
PIC16C72
20I/SS025
AABBCAE
9517SBP
28-Lead PDIP (Skinny DIP)
Example
PIC16C73-10/SP
MMMMMMMMMMMM
XXXXXXXXXXXXXXX
AABBCDE
AABBCDE
28-Lead Side Brazed Skinny Windowed
Example
XXXXXXXXXXX
XXXXXXXXXXX
AABBCDE
PIC16C73/JW
9517CAT
28-Lead SOIC
Example
MMMMMMMMMMMMMMMM
XXXXXXXXXXXXXXXXXXXX
PIC16C73-10/SO
AABBCDE
945/CAA
Legend:
MM...M
XX...X
AA
Microchip part number information
Customer specific information*
Year code (last 2 digits of calender year)
BB
Week code (week of January 1 is week '01’)
C
Facility code of the plant at which wafer is manufactured.
C = Chandler, Arizona, U.S.A.
S = Tempe, Arizona, U.S.A.
D
1
E
Mask revision number for microcontroller
Assembly code of the plant or country of origin in which
part was assembled.
In the event the full Microchip part number cannot be marked on one
line, it will be carried over to the next line thus limiting the number of
available characters for customer specific information.
Note:
*
Standard OTP marking consists of Microchip part number, year code, week code,
facility code, mask revision number, and assembly code. For OTP marking beyond
this, certain price adders apply. Please check with your Microchip Sales Office.
For QTP devices, any special marking adders are included in QTP price.
DS30390E-page 260
1997 Microchip Technology Inc.
PIC16C7X
Package Marking Information (Cont’d)
40-Lead PDIP
Example
PIC16C74-04/P
MMMMMMMMMMMMMM
XXXXXXXXXXXXXXXXXX
AABBCDE
9512CAA
40-Lead CERDIP Windowed
Example
MMMMMMMMM
XXXXXXXXXXX
XXXXXXXXXXX
PIC16C74/JW
AABBCDE
AABBCDE
44-Lead PLCC
Example
MMMMMMMM
XXXXXXXXXX
XXXXXXXXXX
AABBCDE
PIC16C74
-10/L
AABBCDE
44-Lead MQFP
Example
MMMMMMMM
XXXXXXXXXX
XXXXXXXXXX
PIC16C74
-10/PQ
AABBCDE
AABBCDE
Legend:
MM...M
XX...X
AA
Microchip part number information
Customer specific information*
Year code (last 2 digits of calender year)
Week code (week of January 1 is week '01’)
BB
C
Facility code of the plant at which wafer is manufactured.
C = Chandler, Arizona, U.S.A.
S = Tempe, Arizona, U.S.A.
D
1
E
Mask revision number for microcontroller
Assembly code of the plant or country of origin in which
part was assembled.
In the event the full Microchip part number cannot be marked on one
line, it will be carried over to the next line thus limiting the number of
available characters for customer specific information.
Note:
*
Standard OTP marking consists of Microchip part number, year code, week code,
facility code, mask revision number, and assembly code. For OTP marking beyond
this, certain price adders apply. Please check with your Microchip Sales Office.
For QTP devices, any special marking adders are included in QTP price.
1997 Microchip Technology Inc.
DS30390E-page 261
PIC16C7X
Package Marking Information (Cont’d)
44-Lead TQFP
Example
MMMMMMMM
XXXXXXXXXX
XXXXXXXXXX
PIC16C74A
-10/TQ
AABBCDE
AABBCDE
Legend:
MM...M
XX...X
AA
Microchip part number information
Customer specific information*
Year code (last 2 digits of calender year)
Week code (week of January 1 is week '01’)
BB
C
Facility code of the plant at which wafer is manufactured.
C = Chandler, Arizona, U.S.A.
S = Tempe, Arizona, U.S.A.
D
1
E
Mask revision number for microcontroller
Assembly code of the plant or country of origin in which
part was assembled.
In the event the full Microchip part number cannot be marked on one
line, it will be carried over to the next line thus limiting the number of
available characters for customer specific information.
Note:
*
Standard OTP marking consists of Microchip part number, year code, week code,
facility code, mask revision number, and assembly code. For OTP marking beyond
this, certain price adders apply. Please check with your Microchip Sales Office.
For QTP devices, any special marking adders are included in QTP price.
DS30390E-page 262
1997 Microchip Technology Inc.
PIC16C7X
APPENDIX A:
APPENDIX B: COMPATIBILITY
The following are the list of modifications over the
PIC16C5X microcontroller family:
To convert code written for PIC16C5X to PIC16CXX,
the user should take the following steps:
1. Instruction word length is increased to 14-bits.
This allows larger page sizes both in program
memory (2K now as opposed to 512 before) and
register file (128 bytes now versus 32 bytes
before).
1. Remove any program memory page select
operations (PA2, PA1, PA0 bits) for CALL, GOTO.
2. Revisit any computed jump operations (write to
PC or add to PC, etc.) to make sure page bits
are set properly under the new scheme.
2. A PC high latch register (PCLATH) is added to
handle program memory paging. Bits PA2, PA1,
PA0 are removed from STATUS register.
3. Eliminate any data memory page switching.
Redefine data variables to reallocate them.
4. Verify all writes to STATUS, OPTION, and FSR
registers since these have changed.
3. Data memory paging is redefined slightly.
STATUS register is modified.
5. Change reset vector to 0000h.
4. Four new instructions have been added:
RETURN, RETFIE, ADDLW, and SUBLW.
Two instructions TRIS and OPTION are being
phased out although they are kept for compati-
bility with PIC16C5X.
5. OPTION and TRIS registers are made address-
able.
6. Interrupt capability is added. Interrupt vector is
at 0004h.
7. Stack size is increased to 8 deep.
8. Reset vector is changed to 0000h.
9. Reset of all registers is revisited. Five different
reset (and wake-up) types are recognized. Reg-
isters are reset differently.
10. Wake up from SLEEP through interrupt is
added.
11. Two separate timers, Oscillator Start-up Timer
(OST) and Power-up Timer (PWRT) are
included for more reliable power-up. These tim-
ers are invoked selectively to avoid unnecessary
delays on power-up and wake-up.
12. PORTB has weak pull-ups and interrupt on
change feature.
13. T0CKI pin is also a port pin (RA4) now.
14. FSR is made a full eight bit register.
15. “In-circuit serial programming” is made possible.
The user can program PIC16CXX devices using
only five pins: VDD, VSS, MCLR/VPP, RB6 (clock)
and RB7 (data in/out).
16. PCON status register is added with a Power-on
Reset status bit (POR).
17. Code protection scheme is enhanced such that
portions of the program memory can be pro-
tected, while the remainder is unprotected.
18. Brown-out protection circuitry has been added.
Controlled by configuration word bit BODEN.
Brown-out reset ensures the device is placed in
a reset condition if VDD dips below a fixed set-
point.
1997 Microchip Technology Inc.
DS30390E-page 263
PIC16C7X
APPENDIX C: WHAT’S NEW
APPENDIX D: WHAT’S CHANGED
Added the following devices:
Minor changes, spelling and grammatical changes.
• PIC16C76
• PIC16C77
Added the following note to the USART section. This
note applies to all devices except the PIC16C76 and
PIC16C77.
Removed the PIC16C710, PIC16C71, PIC16C711
from this datasheet.
For the PIC16C73/73A/74/74A the asynchronous high
speed mode (BRGH = 1) may experience a high rate of
receive errors. It is recommended that BRGH = 0. If you
desire a higher baud rate than BRGH = 0 can support,
refer to the device errata for additional information or
use the PIC16C76/77.
Added PIC16C76 and PIC16C77 devices. The
PIC16C76/77 devices have 368 bytes of data memory
distributed in 4 banks and 8K of program memory in 4
pages. These two devices have an enhanced SPI that
supports both clock phase and polarity. The USART
has been enhanced.
When upgrading to the PIC16C76/77 please note that
the upper 16 bytes of data memory in banks 1,2, and 3
are mapped into bank 0. This may require relocation of
data memory usage in the user application code.
Divided SPI section into SPI for the PIC16C76/77 and
SPI for all other devices.
Added Q-cycle definitions to the Instruction Set Sum-
mary section.
DS30390E-page 264
1997 Microchip Technology Inc.
PIC16C7X
APPENDIX E: PIC16/17 MICROCONTROLLERS
E.1
PIC12CXXX Family of Devices
PIC12C508
PIC12C509
PIC12C671
PIC12C672
Maximum Frequency
of Operation (MHz)
4
4
4
4
Clock
EPROM Program Memory
Data Memory (bytes)
Timer Module(s)
512 x 12
25
1024 x 12
41
1024 x 14
128
2048 x 14
128
Memory
TMR0
—
TMR0
—
TMR0
4
TMR0
4
Peripherals
A/D Converter (8-bit) Channels
Wake-up from SLEEP on
pin change
Yes
Yes
Yes
Yes
I/O Pins
5
5
5
5
Input Pins
1
1
1
1
Internal Pull-ups
Voltage Range (Volts)
In-Circuit Serial Programming
Number of Instructions
Packages
Yes
Yes
Yes
Yes
Features
2.5-5.5
2.5-5.5
2.5-5.5
2.5-5.5
Yes
Yes
Yes
Yes
33
33
35
35
8-pin DIP, SOIC
8-pin DIP, SOIC
8-pin DIP, SOIC
8-pin DIP, SOIC
All PIC12C5XX devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capability.
All PIC12C5XX devices use serial programming with data pin GP1 and clock pin GP0.
E.2
PIC14C000 Family of Devices
PIC14C000
Clock
Maximum Frequency of Operation (MHz) 20
EPROM Program Memory (x14 words)
Data Memory (bytes)
4K
192
Memory
Timer Module(s)
TMR0
ADTMR
2
Serial Port(s)
(SPI/I C, USART)
I C with SMBus
Peripherals
2
Support
Slope A/D Converter Channels
Interrupt Sources
8 External; 6 Internal
11
I/O Pins
22
Voltage Range (Volts)
In-Circuit Serial Programming
Additional On-chip Features
2.7-6.0
Yes
Features
Internal 4MHz Oscillator, Bandgap Reference,Temperature Sensor,
Calibration Factors, Low Voltage Detector, SLEEP, HIBERNATE,
Comparators with Programmable References (2)
Packages
28-pin DIP (.300 mil), SOIC, SSOP
1997 Microchip Technology Inc.
DS30390E-page 265
PIC16C7X
E.3
PIC16C15X Family of Devices
PIC16C154 PIC16CR154 PIC16C156 PIC16CR156 PIC16C158 PIC16CR158
Maximum Frequency
of Operation (MHz)
20
20
20
1K
—
20
20
2K
—
20
Clock
EPROM Program Memory 512
(x12 words)
—
—
—
Memory
ROM Program Memory
(x12 words)
—
512
1K
2K
RAM Data Memory (bytes) 25
25
25
25
73
73
Peripherals Timer Module(s)
TMR0
12
TMR0
12
TMR0
12
TMR0
12
TMR0
12
TMR0
12
I/O Pins
Voltage Range (Volts)
3.0-5.5
33
2.5-5.5
33
3.0-5.5
33
2.5-5.5
33
3.0-5.5
33
2.5-5.5
33
Number of Instructions
Packages
Features
18-pin DIP, 18-pin DIP,
SOIC; SOIC;
18-pin DIP, 18-pin DIP,
SOIC; SOIC;
18-pin DIP,
SOIC;
18-pin DIP,
SOIC;
20-pin SSOP 20-pin SSOP 20-pin SSOP 20-pin SSOP 20-pin SSOP 20-pin SSOP
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high
I/O current capability.
E.4
PIC16C5X Family of Devices
PIC16C52
PIC16C54
20
PIC16C54A PIC16CR54A PIC16C55
PIC16C56
20
Maximum Frequency
of Operation (MHz)
4
20
20
20
Clock
EPROM Program Memory
(x12 words)
384
—
512
—
512
—
—
512
—
1K
—
Memory
ROM Program Memory
(x12 words)
512
RAM Data Memory (bytes) 25
25
25
25
24
25
Peripherals Timer Module(s)
TMR0
12
TMR0
12
TMR0
12
TMR0
12
TMR0
20
TMR0
12
I/O Pins
Voltage Range (Volts)
2.5-6.25
33
2.5-6.25
33
2.0-6.25
33
2.0-6.25
33
2.5-6.25
33
2.5-6.25
33
Number of Instructions
Packages
Features
18-pin DIP, 18-pin DIP,
SOIC SOIC;
18-pin DIP,
SOIC;
18-pin DIP,
SOIC;
28-pin DIP, 18-pin DIP,
SOIC,
SOIC;
20-pin SSOP 20-pin SSOP 20-pin SSOP SSOP
20-pin SSOP
PIC16C57
PIC16CR57B
PIC16C58A
PIC16CR58A
Maximum Frequency
of Operation (MHz)
20
2K
—
20
—
20
2K
—
20
—
Clock
EPROM Program Memory
(x12 words)
Memory
ROM Program Memory
(x12 words)
2K
72
2K
73
RAM Data Memory (bytes)
72
73
Peripherals Timer Module(s)
TMR0
20
TMR0
20
TMR0
12
TMR0
12
I/O Pins
Voltage Range (Volts)
2.5-6.25
33
2.5-6.25
33
2.0-6.25
33
2.5-6.25
33
Number of Instructions
Packages
Features
28-pin DIP,
SOIC,
28-pin DIP, SOIC, 18-pin DIP, SOIC; 18-pin DIP, SOIC;
SSOP 20-pin SSOP 20-pin SSOP
SSOP
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer (except PIC16C52), selectable code protect and
high I/O current capability.
DS30390E-page 266
1997 Microchip Technology Inc.
PIC16C7X
E.5
PIC16C55X Family of Devices
(1)
PIC16C554
PIC16C556
PIC16C558
Clock
Maximum Frequency of Operation (MHz)
EPROM Program Memory (x14 words)
Data Memory (bytes)
20
20
1K
80
20
512
80
2K
128
Memory
Timer Module(s)
TMR0
—
TMR0
—
TMR0
—
Peripherals Comparators(s)
Internal Reference Voltage
—
—
—
Interrupt Sources
I/O Pins
3
3
3
13
13
13
Voltage Range (Volts)
Brown-out Reset
Packages
2.5-6.0
—
2.5-6.0
—
2.5-6.0
—
Features
18-pin DIP,
SOIC;
18-pin DIP,
SOIC;
18-pin DIP,
SOIC;
20-pin SSOP
20-pin SSOP
20-pin SSOP
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high
I/O current capability. All PIC16C5XX Family devices use serial programming with clock pin RB6 and data pin RB7.
Note 1: Please contact your local Microchip sales office for availability of these devices.
E.6
PIC16C62X and PIC16C64X Family of Devices
PIC16C620
PIC16C621
20
PIC16C622
20
PIC16C642
20
PIC16C662
20
Maximum Frequency
of Operation (MHz)
20
Clock
EPROM Program Memory
(x14 words)
512
1K
2K
4K
4K
Memory
Data Memory (bytes)
Timer Module(s)
80
80
128
TMR0
2
176
TMR0
2
176
TMR0
2
TMR0
2
TMR0
2
Peripherals Comparators(s)
Internal Reference Voltage
Yes
4
Yes
4
Yes
4
Yes
4
Yes
5
Interrupt Sources
I/O Pins
13
13
13
22
33
Voltage Range (Volts)
Brown-out Reset
Packages
2.5-6.0
Yes
2.5-6.0
Yes
2.5-6.0
Yes
3.0-6.0
Yes
3.0-6.0
Yes
Features
18-pin DIP,
SOIC;
18-pin DIP,
SOIC;
18-pin DIP,
SOIC;
28-pin PDIP, 40-pin PDIP,
SOIC,
Windowed
CDIP;
44-pin PLCC,
MQFP
20-pin SSOP 20-pin SSOP 20-pin SSOP Windowed
CDIP
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high
I/O current capability. All PIC16C62X and PIC16C64X Family devices use serial programming with clock pin RB6 and data pin RB7.
1997 Microchip Technology Inc.
DS30390E-page 267
PIC16C7X
E.7
PIC16C6X Family of Devices
PIC16C61
20
PIC16C62A
20
PIC16CR62
20
PIC16C63
20
PIC16CR63
20
Maximum Frequency
of Operation (MHz)
Clock
EPROM Program Memory
(x14 words)
1K
—
2K
—
—
4K
—
—
Memory
ROM Program Memory
(x14 words)
2K
128
4K
192
Data Memory (bytes)
Timer Module(s)
36
128
192
TMR0
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
Capture/Compare/
PWM Module(s)
—
—
1
1
2
2
Peripherals
2
2
2
2
Serial Port(s)
SPI/I C
SPI/I C
SPI/I C,
USART
SPI/I C
USART
2
(SPI/I C, USART)
Parallel Slave Port
Interrupt Sources
I/O Pins
—
—
—
—
—
3
7
7
10
10
13
22
22
22
22
Voltage Range (Volts)
In-Circuit Serial Programming
Brown-out Reset
Packages
3.0-6.0
Yes
—
2.5-6.0
Yes
Yes
2.5-6.0
Yes
Yes
2.5-6.0
Yes
Yes
2.5-6.0
Yes
Yes
Features
18-pin DIP, SO 28-pin SDIP,
SOIC, SSOP
28-pin SDIP,
SOIC, SSOP
28-pin SDIP, 28-pin SDIP,
SOIC SOIC
PIC16C64A PIC16CR64 PIC16C65A PIC16CR65 PIC16C66 PIC16C67
Maximum Frequency
of Operation (MHz)
20
20
20
20
20
20
Clock
EPROM Program Memory
(x14 words)
2K
—
—
4K
—
—
8K
—
8K
—
Memory
ROM Program Memory (x14
words)
2K
128
4K
192
Data Memory (bytes)
Timer Module(s)
128
192
368
368
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
Capture/Compare/PWM Mod-
ule(s)
1
1
2
2
2
2
Peripherals
2
2
2
2
2
2
2
Serial Port(s) (SPI/I C, USART) SPI/I C
SPI/I C
SPI/I C,
SPI/I C,
SPI/I C,
SPI/I C,
USART
USART
USART
USART
Parallel Slave Port
Interrupt Sources
I/O Pins
Yes
8
Yes
8
Yes
Yes
—
Yes
11
11
10
11
33
33
33
33
22
33
Voltage Range (Volts)
In-Circuit Serial Programming
Brown-out Reset
Packages
2.5-6.0
Yes
Yes
2.5-6.0
Yes
Yes
2.5-6.0
Yes
2.5-6.0
Yes
2.5-6.0
Yes
Yes
2.5-6.0
Yes
Yes
Yes
Yes
Features
40-pin DIP; 40-pin DIP;
40-pin DIP;
40-pin DIP; 28-pin SDIP, 40-pin DIP;
44-pin PLCC, 44-pin PLCC, 44-pin PLCC, 44-pin
MQFP, TQFP MQFP, TQFP MQFP, TQFP PLCC,
SOIC
44-pin
PLCC,
MQFP,
TQFP
MQFP,
TQFP
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current
capability. All PIC16C6X Family devices use serial programming with clock pin RB6 and data pin RB7.
DS30390E-page 268
1997 Microchip Technology Inc.
PIC16C7X
E.8
PIC16C8X Family of Devices
PIC16F83
PIC16CR83
PIC16F84
PIC16CR84
Maximum Frequency
of Operation (MHz)
10
10
10
10
Clock
Flash Program Memory
EEPROM Program Memory
ROM Program Memory
Data Memory (bytes)
512
—
—
—
1K
—
—
1K
68
64
—
Memory
—
512
36
—
36
64
68
Data EEPROM (bytes)
64
64
Peripher-
als
Timer Module(s)
TMR0
TMR0
TMR0
TMR0
Interrupt Sources
I/O Pins
4
4
4
4
13
13
13
13
Features
Voltage Range (Volts)
Packages
2.0-6.0
2.0-6.0
2.0-6.0
2.0-6.0
18-pin DIP,
SOIC
18-pin DIP,
SOIC
18-pin DIP,
SOIC
18-pin DIP,
SOIC
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capabil-
ity. All PIC16C8X Family devices use serial programming with clock pin RB6 and data pin RB7.
E.9
PIC16C9XX Family Of Devices
PIC16C923
PIC16C924
Clock
Maximum Frequency of Operation (MHz)
EPROM Program Memory
Data Memory (bytes)
8
8
4K
176
4K
176
Memory
Timer Module(s)
TMR0,
TMR1,
TMR2
TMR0,
TMR1,
TMR2
Capture/Compare/PWM Module(s)
Serial Port(s)
(SPI/I C, USART)
1
1
2
2
SPI/I C
SPI/I C
Peripherals
2
Parallel Slave Port
—
—
—
5
A/D Converter (8-bit) Channels
LCD Module
4 Com,
32 Seg
4 Com,
32 Seg
Interrupt Sources
I/O Pins
8
9
25
25
Input Pins
27
27
Voltage Range (Volts)
In-Circuit Serial Programming
Brown-out Reset
Packages
3.0-6.0
Yes
—
3.0-6.0
Yes
—
Features
(1)
(1)
64-pin SDIP
TQFP;
,
64-pin SDIP
TQFP;
,
68-pin PLCC,
Die
68-pin PLCC,
Die
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capa-
bility. All PIC16C9XX Family devices use serial programming with clock pin RB6 and data pin RB7.
1997 Microchip Technology Inc.
DS30390E-page 269
PIC16C7X
E.10
PIC17CXXX Family of Devices
PIC17C42A
33
PIC17CR42
33
PIC17C43
PIC17CR43
33
PIC17C44
Maximum Frequency
of Operation (MHz)
33
4K
—
33
8K
—
Clock
EPROM Program Memory
(words)
2K
—
—
—
Memory
ROM Program Memory
(words)
2K
232
4K
454
RAM Data Memory (bytes)
Timer Module(s)
232
454
454
TMR0,
TMR1,
TMR2,
TMR3
TMR0,
TMR1,
TMR2,
TMR3
TMR0,
TMR1,
TMR2,
TMR3
TMR0,
TMR1,
TMR2,
TMR3
TMR0,
TMR1,
TMR2,
TMR3
Peripherals
Captures/PWM Module(s)
Serial Port(s) (USART)
Hardware Multiply
External Interrupts
Interrupt Sources
I/O Pins
2
2
2
2
2
Yes
Yes
Yes
11
Yes
Yes
Yes
11
Yes
Yes
Yes
11
Yes
Yes
Yes
11
Yes
Yes
Yes
11
33
33
33
33
33
Features
Voltage Range (Volts)
Number of Instructions
Packages
2.5-6.0
58
2.5-6.0
58
2.5-6.0
58
2.5-6.0
58
2.5-6.0
58
40-pin DIP;
40-pin DIP;
40-pin DIP;
40-pin DIP;
40-pin DIP;
44-pin PLCC,
44-pin PLCC,
44-pin PLCC,
44-pin PLCC,
44-pin PLCC,
MQFP, TQFP MQFP, TQFP MQFP, TQFP MQFP, TQFP MQFP, TQFP
PIC17C752
33
PIC17C756
33
Maximum Frequency
of Operation (MHz)
Clock
EPROM Program Memory
(words)
8K
—
16K
—
Memory
ROM Program Memory
(words)
RAM Data Memory (bytes)
Timer Module(s)
454
902
TMR0,
TMR1,
TMR2,
TMR3
TMR0,
TMR1,
TMR2,
TMR3
Peripherals
Captures/PWM Module(s)
Serial Port(s) (USART)
Hardware Multiply
External Interrupts
Interrupt Sources
I/O Pins
4/3
2
4/3
2
Yes
Yes
18
Yes
Yes
18
50
50
Features
Voltage Range (Volts)
Number of Instructions
Packages
3.0-6.0
58
3.0-6.0
58
64-pin DIP;
68-pin LCC,
68-pin TQFP
64-pin DIP;
68-pin LCC,
68-pin TQFP
All PIC16/17 Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high
I/O current capability.
DS30390E-page 270
1997 Microchip Technology Inc.
PIC16C7X
PIN COMPATIBILITY
Devices that have the same package type and VDD,
VSS and MCLR pin locations are said to be pin
compatible. This allows these different devices to
operate in the same socket. Compatible devices may
only requires minor software modification to allow
proper operation in the application socket
(ex., PIC16C56 and PIC16C61 devices). Not all
devices in the same package size are pin compatible;
for example, the PIC16C62 is compatible with the
PIC16C63, but not the PIC16C55.
Pin compatibility does not mean that the devices offer
the same features. As an example, the PIC16C54 is
pin compatible with the PIC16C71, but does not have
an A/D converter, weak pull-ups on PORTB, or
interrupts.
TABLE E-1:
PIN COMPATIBLE DEVICES
Pin Compatible Devices
Package
PIC12C508, PIC12C509, PIC12C671, PIC12C672
8-pin
PIC16C154, PIC16CR154, PIC16C156,
PIC16CR156, PIC16C158, PIC16CR158,
PIC16C52, PIC16C54, PIC16C54A,
PIC16CR54A,
18-pin,
20-pin
PIC16C56,
PIC16C58A, PIC16CR58A,
PIC16C61,
PIC16C554, PIC16C556, PIC16C558
PIC16C620, PIC16C621, PIC16C622
PIC16C641, PIC16C642, PIC16C661, PIC16C662
PIC16C710, PIC16C71, PIC16C711, PIC16C715
PIC16F83, PIC16CR83,
PIC16F84A, PIC16CR84
PIC16C55, PIC16C57, PIC16CR57B
28-pin
28-pin
PIC16CR62, PIC16C62A, PIC16C63, PIC16CR63,
PIC16C66, PIC16C72, PIC16C73A, PIC16C76
PIC16CR64, PIC16C64A, PIC16C65A,
PIC16CR65, PIC16C67, PIC16C74A, PIC16C77
40-pin
40-pin
PIC17CR42, PIC17C42A,
PIC17C43, PIC17CR43, PIC17C44
PIC16C923, PIC16C924
PIC17C756, PIC17C752
64/68-pin
64/68-pin
1997 Microchip Technology Inc.
DS30390E-page 271
PIC16C7X
NOTES:
DS30390E-page 272
1997 Microchip Technology Inc.
PIC16C7X
Compare .....................................................................73
I C Mode ....................................................................93
INDEX
2
On-Chip Reset Circuit ...............................................133
PIC16C72 ...................................................................10
PIC16C73 ...................................................................11
PIC16C73A .................................................................11
PIC16C74 ...................................................................12
PIC16C74A .................................................................12
PIC16C76 ...................................................................11
PIC16C77 ...................................................................12
PORTC .......................................................................48
PORTD (In I/O Port Mode) .........................................50
PORTD and PORTE as a Parallel Slave Port ............54
PORTE (In I/O Port Mode) .........................................51
PWM ...........................................................................74
RA3:RA0 and RA5 Port Pins ......................................43
RA4/T0CKI Pin ...........................................................43
RB3:RB0 Port Pins .....................................................45
RB7:RB4 Port Pins .....................................................46
SPI Master/Slave Connection .....................................81
A
A/D
Accuracy/Error ......................................................... 124
ADCON0 Register .................................................... 117
ADCON1 Register .................................................... 118
ADIF bit .................................................................... 119
Analog Input Model Block Diagram .......................... 120
Analog-to-Digital Converter ...................................... 117
Block Diagram .......................................................... 119
Configuring Analog Port Pins ................................... 121
Configuring the Interrupt .......................................... 119
Configuring the Module ............................................ 119
Connection Considerations ...................................... 125
Conversion Clock ..................................................... 121
Conversion Time ...................................................... 123
Conversions ............................................................. 122
Converter Characteristics ................ 181, 199, 217, 238
Delays ...................................................................... 120
Effects of a Reset ..................................................... 124
Equations ................................................................. 120
Faster Conversion - Lower Resolution Tradeoff ...... 123
Flowchart of A/D Operation ...................................... 126
GO/DONE bit ........................................................... 119
Internal Sampling Switch (Rss) Impedance ............. 120
Operation During Sleep ........................................... 124
Sampling Requirements ........................................... 120
Sampling Time ......................................................... 120
Source Impedance ................................................... 120
Time Delays ............................................................. 120
Transfer Function ..................................................... 125
Using the CCP Trigger ............................................. 125
Absolute Maximum Ratings ..................... 167, 183, 201, 219
ACK ........................................................................ 90, 94, 95
ADIE bit .............................................................................. 33
ADIF bit .............................................................................. 35
ADRES Register .................................... 23, 25, 27, 117, 119
ALU ...................................................................................... 9
Application Notes
2
SSP in I C Mode ........................................................93
SSP in SPI Mode ..................................................80, 85
Timer0 ........................................................................59
Timer0/WDT Prescaler ...............................................62
Timer1 ........................................................................66
Timer2 ........................................................................69
USART Receive .......................................................108
USART Transmit ......................................................106
Watchdog Timer .......................................................144
BOR bit .......................................................................39, 135
BRGH bit ..........................................................................101
Buffer Full Status bit, BF ...............................................78, 83
C
C bit ....................................................................................30
C Compiler ........................................................................165
Capture/Compare/PWM
Capture
Block Diagram ....................................................72
CCP1CON Register ...........................................72
CCP1IF ...............................................................72
CCPR1 ...............................................................72
CCPR1H:CCPR1L .............................................72
Mode ..................................................................72
Prescaler ............................................................73
CCP Timer Resources ................................................71
Compare
AN546 (Using the Analog-to-Digital Converter) ....... 117
AN552 (Implementing Wake-up on Key Strokes Using
PIC16CXXX) .............................................................. 45
AN556 (Table Reading Using PIC16CXX .................. 40
2
AN578 (Use of the SSP Module in the I C Multi-Master
Environment) .............................................................. 77
AN594 (Using the CCP Modules) .............................. 71
AN607, Power-up Trouble Shooting ........................ 134
Architecture
Harvard ........................................................................ 9
Overview ...................................................................... 9
von Neumann ............................................................... 9
Assembler
Block Diagram ....................................................73
Mode ..................................................................73
Software Interrupt Mode .....................................73
Special Event Trigger .........................................73
Special Trigger Output of CCP1 .........................73
Special Trigger Output of CCP2 .........................73
Interaction of Two CCP Modules ................................71
Section ........................................................................71
Special Event Trigger and A/D Conversions ..............73
Capture/Compare/PWM (CCP)
PWM Block Diagram ..................................................74
PWM Mode .................................................................74
PWM, Example Frequencies/Resolutions ..................75
Carry bit ................................................................................9
CCP1CON ..........................................................................29
CCP1IE bit ..........................................................................33
CCP1IF bit ....................................................................35, 36
CCP2CON ..........................................................................29
CCP2IE bit ..........................................................................37
MPASM Assembler .................................................. 164
B
Baud Rate Error ............................................................... 101
Baud Rate Formula .......................................................... 101
Baud Rates
Asynchronous Mode ................................................ 102
Synchronous Mode .................................................. 102
BF .......................................................................... 78, 83, 94
Block Diagrams
A/D ........................................................................... 119
Analog Input Model .................................................. 120
Capture ...................................................................... 72
1997 Microchip Technology Inc.
DS30390E-page 273
PIC16C7X
CCP2IF bit .......................................................................... 38
CCPR1H Register ............................................ 25, 27, 29, 71
CCPR1L Register ......................................................... 29, 71
CCPR2H Register ............................................ 25, 27, 29, 71
CCPR2L Register ............................................. 25, 27, 29, 71
CCPxM0 bit ........................................................................ 72
CCPxM1 bit ........................................................................ 72
CCPxM2 bit ........................................................................ 72
CCPxM3 bit ........................................................................ 72
CCPxX bit ........................................................................... 72
CCPxY bit ........................................................................... 72
CKE .................................................................................... 83
CKP .............................................................................. 79, 84
Clock Polarity Select bit, CKP ...................................... 79, 84
Clock Polarity, SPI Mode ................................................... 81
Clocking Scheme ............................................................... 17
Code Examples
F
Family of Devices
PIC12CXXX ............................................................. 265
PIC14C000 .............................................................. 265
PIC16C15X .............................................................. 266
PIC16C55X .............................................................. 267
PIC16C5X ................................................................ 266
PIC16C62X and PIC16C64X ................................... 267
PIC16C6X ................................................................ 268
PIC16C7XX ................................................................. 6
PIC16C8X ................................................................ 269
PIC16C9XX ............................................................. 269
PIC17CXX ............................................................... 270
FERR bit .......................................................................... 100
FSR Register ........................... 23, 24, 25, 26, 27, 28, 29, 41
Fuzzy Logic Dev. System (fuzzyTECH -MP) ......... 163, 165
Call of a Subroutine in Page 1 from Page 0 ............... 41
Changing Between Capture Prescalers ..................... 73
Changing Prescaler (Timer0 to WDT) ........................ 63
Changing Prescaler (WDT to Timer0) ........................ 63
I/O Programming ........................................................ 53
Indirect Addressing .................................................... 41
Initializing PORTA ...................................................... 43
Initializing PORTB ...................................................... 45
Initializing PORTC ...................................................... 48
Loading the SSPBUF Register ............................ 80, 85
Code Protection ....................................................... 129, 146
Computed GOTO ............................................................... 40
Configuration Bits ............................................................. 129
Configuration Word .......................................................... 129
Connecting Two Microcontrollers ....................................... 81
CREN bit .......................................................................... 100
CS pin ................................................................................ 54
G
General Description ............................................................. 5
GIE bit .............................................................................. 141
I
I/O Ports
PORTA ...................................................................... 43
PORTB ...................................................................... 45
PORTC ...................................................................... 48
PORTD ................................................................ 50, 54
PORTE ...................................................................... 51
Section ....................................................................... 43
I/O Programming Considerations ...................................... 53
2
I C
Addressing ................................................................. 94
Addressing I C Devices ............................................. 90
2
Arbitration .................................................................. 92
Block Diagram ........................................................... 93
Clock Synchronization ............................................... 92
Combined Format ...................................................... 91
D
D/A ............................................................................... 78, 83
Data/Address bit, D/A ................................................... 78, 83
DC bit ................................................................................. 30
DC Characteristics
2
I C Operation ............................................................. 93
2
I C Overview ............................................................. 89
Initiating and Terminating Data Transfer ................... 89
Master Mode .............................................................. 97
Master-Receiver Sequence ....................................... 91
Master-Transmitter Sequence ................................... 91
Mode .......................................................................... 93
Mode Selection .......................................................... 93
Multi-master ............................................................... 92
Multi-Master Mode ..................................................... 97
Reception .................................................................. 95
Reception Timing Diagram ........................................ 95
SCL and SDA pins ..................................................... 94
Slave Mode ................................................................ 94
START ....................................................................... 89
STOP ................................................................... 89, 90
Transfer Acknowledge ............................................... 90
Transmission ............................................................. 96
IDLE_MODE ...................................................................... 98
In-Circuit Serial Programming .................................. 129, 146
INDF .................................................................................. 29
INDF Register ...................................... 24, 25, 26, 27, 28, 41
Indirect Addressing ............................................................ 41
Initialization Condition for all Register .............................. 136
Instruction Cycle ................................................................ 17
Instruction Flow/Pipelining ................................................. 17
Instruction Format ............................................................ 147
PIC16C72 ................................................................ 168
PIC16C73 ................................................................ 184
PIC16C73A .............................................................. 202
PIC16C74 ................................................................ 184
PIC16C74A .............................................................. 202
PIC16C76 ................................................................ 221
PIC16C77 ................................................................ 221
Development Support .................................................. 5, 163
Development Tools .......................................................... 163
Digit Carry bit ....................................................................... 9
Direct Addressing ............................................................... 41
E
Electrical Characteristics
PIC16C72 ................................................................ 167
PIC16C73 ................................................................ 183
PIC16C73A .............................................................. 201
PIC16C74 ................................................................ 183
PIC16C74A .............................................................. 201
PIC16C76 ................................................................ 219
PIC16C77 ................................................................ 219
External Brown-out Protection Circuit .............................. 140
External Power-on Reset Circuit ...................................... 140
DS30390E-page 274
1997 Microchip Technology Inc.
PIC16C7X
Instruction Set
ADDLW .................................................................... 149
M
MCLR .......................................................................133, 136
Memory
ADDWF .................................................................... 149
ANDLW .................................................................... 149
ANDWF .................................................................... 149
BCF .......................................................................... 150
BSF .......................................................................... 150
BTFSC ..................................................................... 150
BTFSS ..................................................................... 151
CALL ........................................................................ 151
CLRF ........................................................................ 152
CLRW ...................................................................... 152
CLRWDT .................................................................. 152
COMF ...................................................................... 153
DECF ....................................................................... 153
DECFSZ ................................................................... 153
GOTO ...................................................................... 154
INCF ......................................................................... 154
INCFSZ .................................................................... 155
IORLW ..................................................................... 155
IORWF ..................................................................... 156
MOVF ....................................................................... 156
MOVLW ................................................................... 156
MOVWF ................................................................... 156
NOP ......................................................................... 157
OPTION ................................................................... 157
RETFIE .................................................................... 157
RETLW .................................................................... 158
RETURN .................................................................. 158
RLF .......................................................................... 159
RRF .......................................................................... 159
SLEEP ..................................................................... 160
SUBLW .................................................................... 160
SUBWF .................................................................... 161
SWAPF .................................................................... 161
TRIS ......................................................................... 161
XORLW .................................................................... 162
XORWF .................................................................... 162
Section ..................................................................... 147
Summary Table ........................................................ 148
INT Interrupt ..................................................................... 143
INTCON ............................................................................. 29
INTCON Register ............................................................... 32
INTEDG bit ................................................................. 31, 143
Internal Sampling Switch (Rss) Impedance ..................... 120
Interrupts .......................................................................... 129
PortB Change .......................................................... 143
RB7:RB4 Port Change ............................................... 45
Section ..................................................................... 141
TMR0 ....................................................................... 143
IRP bit ................................................................................ 30
Data Memory ..............................................................20
Program Memory ........................................................19
Program Memory Maps
PIC16C72 ...........................................................19
PIC16C73 ...........................................................19
PIC16C73A ........................................................19
PIC16C74 ...........................................................19
PIC16C74A ........................................................19
PIC16C76 ...........................................................20
PIC16C77 ...........................................................20
Register File Maps
PIC16C72 ...........................................................21
PIC16C73 ...........................................................21
PIC16C73A ........................................................21
PIC16C74 ...........................................................21
PIC16C74A ........................................................21
PIC16C76 ...........................................................21
PIC16C77 ...........................................................21
MPASM Assembler ..........................................................163
MPLAB-C ..........................................................................165
MPSIM Software Simulator ......................................163, 165
O
OERR bit ..........................................................................100
OPCODE ..........................................................................147
OPTION ..............................................................................29
OPTION Register ...............................................................31
Orthogonal ............................................................................9
OSC selection ...................................................................129
Oscillator
HS .....................................................................131, 135
LP .....................................................................131, 135
RC ............................................................................131
XT .....................................................................131, 135
Oscillator Configurations ..................................................131
Output of TMR2 ..................................................................69
P
P ...................................................................................78, 83
Packaging
28-Lead Ceramic w/Window .....................................251
28-Lead PDIP ...........................................................253
28-Lead SOIC ...........................................................255
28-Lead SSOP .........................................................256
40-Lead CERDIP w/Window ....................................252
40-Lead PDIP ...........................................................254
44-Lead MQFP .........................................................258
44-Lead PLCC ..........................................................257
44-Lead TQFP ..........................................................259
Paging, Program Memory ...................................................40
Parallel Slave Port ........................................................50, 54
PCFG0 bit .........................................................................118
PCFG1 bit .........................................................................118
PCFG2 bit .........................................................................118
PCL Register ............................23, 24, 25, 26, 27, 28, 29, 40
PCLATH ...........................................................................136
PCLATH Register .....................23, 24, 25, 26, 27, 28, 29, 40
PCON Register .....................................................29, 39, 135
PD bit ..................................................................30, 133, 135
PICDEM-1 Low-Cost PIC16/17 Demo Board ...........163, 164
PICDEM-2 Low-Cost PIC16CXX Demo Board .........163, 164
PICDEM-3 Low-Cost PIC16C9XXX Demo Board ............164
PICMASTER In-Circuit Emulator ......................................163
L
Loading of PC .................................................................... 40
1997 Microchip Technology Inc.
DS30390E-page 275
PIC16C7X
PICSTART Low-Cost Development System .................... 163
PIE1 Register ............................................................... 29, 33
PIE2 Register ............................................................... 29, 37
Pin Compatible Devices ................................................... 271
Pin Functions
POR ......................................................................... 134, 135
Oscillator Start-up Timer (OST) ....................... 129, 134
Power Control Register (PCON) .............................. 135
Power-on Reset (POR) ............................ 129, 134, 136
Power-up Timer (PWRT) ................................. 129, 134
Power-Up-Timer (PWRT) ........................................ 134
Time-out Sequence ................................................. 135
Time-out Sequence on Power-up ............................ 139
TO .................................................................... 133, 135
POR bit ...................................................................... 39, 135
Port RB Interrupt .............................................................. 143
PORTA ...................................................................... 29, 136
PORTA Register .............................................. 23, 25, 27, 43
PORTB ...................................................................... 29, 136
PORTB Register .............................................. 23, 25, 27, 45
PORTC ...................................................................... 29, 136
PORTC Register .............................................. 23, 25, 27, 48
PORTD ...................................................................... 29, 136
PORTD Register .................................................... 25, 27, 50
PORTE ...................................................................... 29, 136
PORTE Register .................................................... 25, 27, 51
Power-down Mode (SLEEP) ............................................ 145
PR2 .................................................................................... 29
PR2 Register ......................................................... 26, 28, 69
Prescaler, Switching Between Timer0 and WDT ............... 63
PRO MATE Universal Programmer ................................. 163
Program Branches ............................................................... 9
Program Memory
MCLR/VPP ...................................................... 13, 14, 15
OSC1/CLKIN .................................................. 13, 14, 15
OSC2/CLKOUT .............................................. 13, 14, 15
RA0/AN0 ........................................................ 13, 14, 15
RA1/AN1 ........................................................ 13, 14, 15
RA2/AN2 ........................................................ 13, 14, 15
RA3/AN3/VREF ............................................... 13, 14, 15
RA4/T0CKI ..................................................... 13, 14, 15
RA5/AN4/SS .................................................. 13, 14, 15
RB0/INT ......................................................... 13, 14, 15
RB1 ................................................................ 13, 14, 15
RB2 ................................................................ 13, 14, 15
RB3 ................................................................ 13, 14, 15
RB4 ................................................................ 13, 14, 15
RB5 ................................................................ 13, 14, 15
RB6 ................................................................ 13, 14, 15
RB7 ................................................................ 13, 14, 15
RC0/T1OSO/T1CKI ....................................... 13, 14, 16
RC1/T1OSI ................................................................ 13
RC1/T1OSI/CCP2 ................................................ 14, 16
RC2/CCP1 ..................................................... 13, 14, 16
RC3/SCK/SCL ............................................... 13, 14, 16
RC4/SDI/SDA ................................................ 13, 14, 16
RC5/SDO ....................................................... 13, 14, 16
RC6 ............................................................................ 13
RC6/TX/CK ............................................14, 16, 99–114
RC7 ............................................................................ 13
RC7/RX/DT ............................................14, 16, 99–114
RD0/PSP0 .................................................................. 16
RD1/PSP1 .................................................................. 16
RD2/PSP2 .................................................................. 16
RD3/PSP3 .................................................................. 16
RD4/PSP4 .................................................................. 16
RD5/PSP5 .................................................................. 16
RD6/PSP6 .................................................................. 16
RD7/PSP7 .................................................................. 16
RE0/RD/AN5 .............................................................. 16
RE1/WR/AN6 ............................................................. 16
RE2/CS/AN7 .............................................................. 16
SCK ...................................................................... 80–82
SDI ....................................................................... 80–82
SDO ..................................................................... 80–82
SS ........................................................................ 80–82
VDD ................................................................ 13, 14, 16
VSS ................................................................. 13, 14, 16
Pinout Descriptions
Paging ....................................................................... 40
Program Memory Maps
PIC16C72 .................................................................. 19
PIC16C73 .................................................................. 19
PIC16C73A ................................................................ 19
PIC16C74 .................................................................. 19
PIC16C74A ................................................................ 19
Program Verification ........................................................ 146
PS0 bit ............................................................................... 31
PS1 bit ............................................................................... 31
PS2 bit ............................................................................... 31
PSA bit ............................................................................... 31
PSPIE bit ........................................................................... 34
PSPIF bit ............................................................................ 36
PSPMODE bit ........................................................ 50, 51, 54
PUSH ................................................................................. 40
R
R/W .............................................................................. 78, 83
R/W bit ............................................................. 90, 94, 95, 96
RBIF bit ...................................................................... 45, 143
RBPU bit ............................................................................ 31
RC Oscillator ............................................................ 132, 135
RCIE bit ............................................................................. 34
RCIF bit .............................................................................. 36
RCREG .............................................................................. 29
RCSTA Register ........................................................ 29, 100
RCV_MODE ...................................................................... 98
RD pin ................................................................................ 54
Read/Write bit Information, R/W .................................. 78, 83
Read-Modify-Write ............................................................. 53
Receive Overflow Detect bit, SSPOV ................................ 79
Receive Overflow Indicator bit, SSPOV ............................. 84
Register File ....................................................................... 20
PIC16C72 .................................................................. 13
PIC16C73 .................................................................. 14
PIC16C73A ................................................................ 14
PIC16C74 .................................................................. 15
PIC16C74A ................................................................ 15
PIC16C76 .................................................................. 14
PIC16C77 .................................................................. 15
PIR1 Register ..................................................................... 35
PIR2 Register ..................................................................... 38
POP .................................................................................... 40
DS30390E-page 276
1997 Microchip Technology Inc.
PIC16C7X
Registers
FSR
SPBRG Register ...........................................................26, 28
Special Event Trigger .......................................................125
Special Features of the CPU ............................................129
Special Function Registers
Summary ........................................................... 29
Summary ........................................................... 29
INDF
PIC16C72 ...................................................................23
PIC16C73 .............................................................25, 27
PIC16C73A ...........................................................25, 27
PIC16C74 .............................................................25, 27
PIC16C74A ...........................................................25, 27
PIC16C76 ...................................................................27
PIC16C77 ...................................................................27
Special Function Registers, Section ...................................23
SPEN bit ...........................................................................100
SPI
Block Diagram ......................................................80, 85
Master Mode ...............................................................86
Master Mode Timing ...................................................87
Mode ...........................................................................80
Serial Clock ................................................................85
Serial Data In ..............................................................85
Serial Data Out ...........................................................85
Slave Mode Timing .....................................................88
Slave Mode Timing Diagram ......................................87
Slave Select ................................................................85
SPI clock .....................................................................86
SPI Mode ....................................................................85
SSPCON ....................................................................84
SSPSTAT ...................................................................83
SPI Clock Edge Select bit, CKE .........................................83
SPI Data Input Sample Phase Select bit, SMP ..................83
SPI Mode ............................................................................80
SREN bit ...........................................................................100
SS .......................................................................................80
SSP
Initialization Conditions ............................................ 136
INTCON
Summary ........................................................... 29
Maps
PIC16C72 .......................................................... 21
PIC16C73 .......................................................... 21
PIC16C73A ........................................................ 21
PIC16C74 .......................................................... 21
PIC16C74A ........................................................ 21
PIC16C76 .......................................................... 22
PIC16C77 .......................................................... 22
OPTION
Summary ........................................................... 29
PCL
Summary ........................................................... 29
PCLATH
Summary ........................................................... 29
PORTB
Summary ........................................................... 29
Reset Conditions ...................................................... 136
SSPBUF
Section ............................................................... 80
SSPCON
Diagram ............................................................. 79
SSPSR
Section ............................................................... 80
SSPSTAT ................................................................... 83
Diagram ............................................................. 78
Section ............................................................... 78
STATUS
Summary ........................................................... 29
Summary .............................................................. 25, 27
TMR0
Module Overview ........................................................77
Section ........................................................................77
SSPBUF .....................................................................86
SSPCON ....................................................................84
SSPSR .......................................................................86
SSPSTAT ...................................................................83
Summary ........................................................... 29
TRISB
2
2
Summary ........................................................... 29
Reset ........................................................................ 129, 133
Reset Conditions for Special Registers ........................... 136
RP0 bit ......................................................................... 20, 30
RP1 bit ............................................................................... 30
RX9 bit ............................................................................. 100
RX9D bit ........................................................................... 100
SSP in I C Mode - See I C
SSPADD .............................................................................93
SSPADD Register ............................................24, 26, 28, 29
SSPBUF .......................................................................29, 93
SSPBUF Register .........................................................25, 27
SSPCON ......................................................................79, 84
SSPCON Register ........................................................25, 27
SSPEN .........................................................................79, 84
SSPIE bit ............................................................................33
SSPIF bit ......................................................................35, 36
SSPM3:SSPM0 ............................................................79, 84
SSPOV ...................................................................79, 84, 94
SSPSTAT .....................................................................78, 93
SSPSTAT Register .....................................24, 26, 28, 29, 83
Stack ...................................................................................40
Overflows ....................................................................40
Underflow ...................................................................40
Start bit, S .....................................................................78, 83
STATUS Register .........................................................29, 30
Stop bit, P .....................................................................78, 83
Synchronous Serial Port (SSP)
S
S ................................................................................... 78, 83
SCK .................................................................................... 80
SCL .................................................................................... 94
SDI ..................................................................................... 80
SDO ................................................................................... 80
Serial Communication Interface (SCI) Module, See USART
Services
One-Time-Programmable (OTP) ................................. 7
Quick-Turnaround-Production (QTP) ........................... 7
Serialized Quick-Turnaround Production (SQTP) ........ 7
Slave Mode
SCL ............................................................................ 94
SDA ............................................................................ 94
SLEEP ..................................................................... 129, 133
SMP ................................................................................... 83
Software Simulator (MPSIM) ........................................... 165
SPBRG .............................................................................. 29
Block Diagram, SPI Mode ..........................................80
SPI Master/Slave Diagram .........................................81
SPI Mode ....................................................................80
Synchronous Serial Port Enable bit, SSPEN ................79, 84
1997 Microchip Technology Inc.
DS30390E-page 277
PIC16C7X
Synchronous Serial Port Mode Select bits,
External Clock Timing ...................... 173, 189, 207, 226
2
SSPM3:SSPM0 ............................................................ 79, 84
Synchronous Serial Port Module ........................................ 77
Synchronous Serial Port Status Register ........................... 83
I C Bus Data .................................... 180, 197, 215, 236
2
I C Bus Start/Stop bits ..................... 179, 196, 214, 235
2
I C Clock Synchronization ......................................... 92
2
I C Data Transfer Wait State ..................................... 90
T
2
I C Multi-Master Arbitration ....................................... 92
2
T0CS bit ............................................................................. 31
T1CKPS0 bit ...................................................................... 65
T1CKPS1 bit ...................................................................... 65
T1CON ............................................................................... 29
T1CON Register ........................................................... 29, 65
T1OSCEN bit ..................................................................... 65
T1SYNC bit ........................................................................ 65
T2CKPS0 bit ...................................................................... 70
T2CKPS1 bit ...................................................................... 70
T2CON Register ........................................................... 29, 70
TAD ................................................................................... 121
Timer Modules, Overview .................................................. 57
Timer0
I C Reception (7-bit Address) .................................... 95
Parallel Slave Port ................................................... 194
Power-up Timer ............................... 175, 191, 209, 228
Reset ............................................... 175, 191, 209, 228
SPI Master Mode ....................................................... 87
SPI Mode ................................................. 178, 195, 213
SPI Mode, Master/Slave Mode, No SS Control ......... 82
SPI Mode, Slave Mode With SS Control ................... 82
SPI Slave Mode (CKE = 1) ........................................ 88
SPI Slave Mode Timing (CKE = 0) ............................ 87
Start-up Timer .................................. 175, 191, 209, 228
Time-out Sequence ................................................. 139
Timer0 ....................................... 59, 176, 192, 210, 229
Timer0 Interrupt Timing ............................................. 60
Timer0 with External Clock ........................................ 61
Timer1 ............................................. 176, 192, 210, 229
USART Asynchronous Master Transmission .......... 107
USART Asynchronous Reception ........................... 108
USART RX Pin Sampling ................................ 104, 105
USART Synchronous Receive ................ 198, 216, 237
USART Synchronous Reception ............................. 113
USART Synchronous Transmission 111, 198, 216, 237
Wake-up from Sleep via Interrupt ............................ 146
Watchdog Timer .............................. 175, 191, 209, 228
TMR0 ................................................................................. 29
TMR0 Register ............................................................. 25, 27
TMR1CS bit ....................................................................... 65
TMR1H .............................................................................. 29
TMR1H Register .................................................... 23, 25, 27
TMR1IE bit ......................................................................... 33
TMR1IF bit ................................................................... 35, 36
TMR1L ............................................................................... 29
TMR1L Register ..................................................... 23, 25, 27
TMR1ON bit ....................................................................... 65
TMR2 ................................................................................. 29
TMR2 Register ....................................................... 23, 25, 27
TMR2IE bit ......................................................................... 33
TMR2IF bit ................................................................... 35, 36
TMR2ON bit ....................................................................... 70
TO bit ................................................................................. 30
TOUTPS0 bit ..................................................................... 70
TOUTPS1 bit ..................................................................... 70
TOUTPS2 bit ..................................................................... 70
TOUTPS3 bit ..................................................................... 70
TRISA ................................................................................ 29
TRISA Register ................................................ 24, 26, 28, 43
TRISB ................................................................................ 29
TRISB Register ................................................ 24, 26, 28, 45
TRISC ................................................................................ 29
TRISC Register ................................................ 24, 26, 28, 48
TRISD ................................................................................ 29
TRISD Register ...................................................... 26, 28, 50
TRISE ................................................................................ 29
TRISE Register ...................................................... 26, 28, 51
Two’s Complement .............................................................. 9
TXIE bit .............................................................................. 34
TXIF bit .............................................................................. 36
TXREG .............................................................................. 29
TXSTA ............................................................................... 29
TXSTA Register ................................................................. 99
RTCC ....................................................................... 136
Timers
Timer0
Block Diagram .................................................... 59
External Clock .................................................... 61
External Clock Timing ........................................ 61
Increment Delay ................................................. 61
Interrupt .............................................................. 59
Interrupt Timing .................................................. 60
Overview ............................................................ 57
Prescaler ............................................................ 62
Prescaler Block Diagram ................................... 62
Section ............................................................... 59
Switching Prescaler Assignment ........................ 63
Synchronization ................................................. 61
T0CKI ................................................................. 61
T0IF .................................................................. 143
Timing ................................................................ 59
TMR0 Interrupt ................................................. 143
Timer1
Asynchronous Counter Mode ............................ 67
Block Diagram .................................................... 66
Capacitor Selection ............................................ 67
External Clock Input ........................................... 66
External Clock Input Timing ............................... 67
Operation in Timer Mode ................................... 66
Oscillator ............................................................ 67
Overview ............................................................ 57
Prescaler ...................................................... 66, 68
Resetting of Timer1 Registers ........................... 68
Resetting Timer1 using a CCP Trigger Output .. 68
Synchronized Counter Mode ............................. 66
T1CON ............................................................... 65
TMR1H ............................................................... 67
TMR1L ............................................................... 67
Timer2
Block Diagram .................................................... 69
Module ............................................................... 69
Overview ............................................................ 57
Postscaler .......................................................... 69
Prescaler ............................................................ 69
T2CON ............................................................... 70
Timing Diagrams
A/D Conversion ................................182, 200, 218, 239
Brown-out Reset ..............................134, 175, 209, 228
Capture/Compare/PWM ...................177, 193, 211, 230
CLKOUT and I/O ..............................174, 190, 208, 227
DS30390E-page 278
1997 Microchip Technology Inc.
PIC16C7X
U
LIST OF EXAMPLES
UA ................................................................................ 78, 83
Universal Synchronous Asynchronous Receiver Transmitter
(USART) ............................................................................ 99
Update Address bit, UA ............................................... 78, 83
USART
Example 3-1: Instruction Pipeline Flow............................17
Example 4-1: Call of a Subroutine in Page 1
from Page 0 ..............................................41
Example 4-2: Indirect Addressing....................................41
Example 5-1: Initializing PORTA......................................43
Example 5-2: Initializing PORTB......................................45
Example 5-3: Initializing PORTC .....................................48
Example 5-4: Read-Modify-Write Instructions
Asynchronous Mode ................................................ 106
Asynchronous Receiver ........................................... 108
Asynchronous Reception ......................................... 109
Asynchronous Transmission .................................... 107
Asynchronous Transmitter ....................................... 106
Baud Rate Generator (BRG) .................................... 101
Receive Block Diagram ............................................ 108
Sampling .................................................................. 104
Synchronous Master Mode ...................................... 110
Synchronous Master Reception ............................... 112
Synchronous Master Transmission .......................... 110
Synchronous Slave Mode ........................................ 114
Synchronous Slave Reception ................................. 114
Synchronous Slave Transmit ................................... 114
Transmit Block Diagram ........................................... 106
UV Erasable Devices ........................................................... 7
on an I/O Port ............................................53
Example 7-1: Changing Prescaler (Timer0→WDT).........63
Example 7-2: Changing Prescaler (WDT→Timer0).........63
Example 8-1: Reading a 16-bit Free-Running Timer .......67
Example 10-1: Changing Between Capture
Prescalers.................................................73
Example 10-2: PWM Period and Duty Cycle
Calculation.................................................75
Example 11-1: Loading the SSPBUF (SSPSR)
Register ....................................................80
Example 11-2: Loading the SSPBUF (SSPSR)
Register (PIC16C76/77) ...........................85
Example 12-1: Calculating Baud Rate Error....................101
Equation 13-1: A/D Minimum Charging Time...................120
Example 13-1: Calculating the Minimum Required
Acquisition Time .....................................120
Example 13-2: A/D Conversion........................................122
Example 13-3: 4-bit vs. 8-bit Conversion Times ..............123
Example 14-1: Saving STATUS, W, and PCLATH
Registers in RAM.....................................143
W
W Register
ALU .............................................................................. 9
Wake-up from SLEEP ...................................................... 145
Watchdog Timer (WDT) ........................... 129, 133, 136, 144
WCOL .......................................................................... 79, 84
WDT ................................................................................. 136
Block Diagram .......................................................... 144
Period ....................................................................... 144
Programming Considerations .................................. 144
Timeout .................................................................... 136
Word ................................................................................ 129
WR pin ............................................................................... 54
Write Collision Detect bit, WCOL ................................. 79, 84
X
XMIT_MODE ...................................................................... 98
Z
Z bit .................................................................................... 30
Zero bit ................................................................................. 9
1997 Microchip Technology Inc.
DS30390E-page 279
PIC16C7X
Figure 8-1:
T1CON: Timer1 Control Register
LIST OF FIGURES
(Address 10h) .......................................... 65
Timer1 Block Diagram .............................. 66
Timer2 Block Diagram .............................. 69
T2CON: Timer2 Control Register
(Address 12h) .......................................... 70
CCP1CON Register (Address 17h)/
CCP2CON Register (Address 1Dh).......... 72
Capture Mode Operation
Block Diagram .......................................... 72
Compare Mode Operation
Figure 8-2:
Figure 9-1:
Figure 9-2:
Figure 3-1:
Figure 3-2:
Figure 3-3:
Figure 3-4:
Figure 4-1:
PIC16C72 Block Diagram ......................... 10
PIC16C73/73A/76 Block Diagram............. 11
PIC16C74/74A/77 Block Diagram............. 12
Clock/Instruction Cycle.............................. 17
PIC16C72 Program Memory Map
Figure 10-1:
Figure 10-2:
Figure 10-3:
and Stack .................................................. 19
PIC16C73/73A/74/74A Program
Memory Map and Stack ............................ 19
PIC16C76/77 Program Memory
Figure 4-2:
Figure 4-3:
Block Diagram .......................................... 73
Simplified PWM Block Diagram................ 74
PWM Output ............................................. 74
SSPSTAT: Sync Serial Port Status
Register (Address 94h)............................. 78
SSPCON: Sync Serial Port Control
Map and Stack .......................................... 20
PIC16C72 Register File Map .................... 21
PIC16C73/73A/74/74A Register
File Map .................................................... 21
PIC16C76/77 Register File Map ............... 22
Status Register (Address 03h,
Figure 10-4:
Figure 10-5:
Figure 11-1:
Figure 4-4:
Figure 4-5:
Figure 4-6:
Figure 4-7:
Figure 11-2:
Register (Address 14h)............................. 79
SSP Block Diagram (SPI Mode)............... 80
SPI Master/Slave Connection................... 81
SPI Mode Timing, Master Mode
or Slave Mode w/o SS Control.................. 82
SPI Mode Timing, Slave Mode with
SS Control ................................................ 82
SSPSTAT: Sync Serial Port Status
Register (Address 94h)(PIC16C76/77)..... 83
SSPCON: Sync Serial Port Control
83h, 103h, 183h)...................................... 30
OPTION Register (Address 81h,
181h)......................................................... 31
INTCON Register
(Address 0Bh, 8Bh, 10bh, 18bh)............... 32
PIE1 Register PIC16C72
(Address 8Ch)........................................... 33
PIE1 Register PIC16C73/73A/
74/74A/76/77 (Address 8Ch)..................... 34
PIR1 Register PIC16C72
(Address 0Ch)........................................... 35
PIR1 Register PIC16C73/73A/
Figure 11-3:
Figure 11-4:
Figure 11-5:
Figure 4-8:
Figure 4-9:
Figure 4-10:
Figure 4-11:
Figure 4-12:
Figure 4-13:
Figure 11-6:
Figure 11-7:
Figure 11-8:
Figure 11-9:
Register (Address 14h)(PIC16C76/77)..... 84
SSP Block Diagram (SPI Mode)
(PIC16C76/77).......................................... 85
74/74A/76/77 (Address 0Ch)..................... 36
PIE2 Register (Address 8Dh).................... 37
PIR2 Register (Address 0Dh).................... 38
PCON Register (Address 8Eh) ................. 39
Loading of PC In Different
Situations .................................................. 40
Direct/Indirect Addressing......................... 41
Block Diagram of RA3:RA0
and RA5 Pins ............................................ 43
Block Diagram of RA4/T0CKI Pin ............. 43
Block Diagram of RB3:RB0 Pins............... 45
Block Diagram of RB7:RB4 Pins
Figure 11-10: SPI Master/Slave Connection
PIC16C76/77)........................................... 86
Figure 11-11: SPI Mode Timing, Master Mode
(PIC16C76/77)......................................... 87
Figure 11-12: SPI Mode Timing (Slave Mode
With CKE = 0) (PIC16C76/77)................. 87
Figure 11-13: SPI Mode Timing (Slave Mode
With CKE = 1) (PIC16C76/77).................. 88
Figure 4-14:
Figure 4-15:
Figure 4-16:
Figure 4-17:
Figure 4-18:
Figure 5-1:
Figure 11-14: Start and Stop Conditions......................... 89
Figure 11-15: 7-bit Address Format ................................ 90
Figure 5-2:
Figure 5-3:
Figure 5-4:
2
Figure 11-16: I C 10-bit Address Format........................ 90
Figure 11-17: Slave-receiver Acknowledge .................... 90
Figure 11-18: Data Transfer Wait State .......................... 90
Figure 11-19: Master-transmitter Sequence ................... 91
Figure 11-20: Master-receiver Sequence........................ 91
Figure 11-21: Combined Format..................................... 91
Figure 11-22: Multi-master Arbitration
(PIC16C73/74) .......................................... 46
Block Diagram of
RB7:RB4 Pins (PIC16C72/73A/
74A/76/77)................................................. 46
PORTC Block Diagram
(Peripheral Output Override).................... 48
PORTD Block Diagram
Figure 5-5:
Figure 5-6:
Figure 5-7:
Figure 5-8:
(Two Masters)........................................... 92
Figure 11-23: Clock Synchronization .............................. 92
Figure 11-24: SSP Block Diagram
(in I/O Port Mode)..................................... 50
PORTE Block Diagram
2
(I C Mode) ................................................ 93
(in I/O Port Mode)..................................... 51
TRISE Register (Address 89h).................. 51
Successive I/O Operation ......................... 53
PORTD and PORTE Block Diagram
(Parallel Slave Port) .................................. 54
Parallel Slave Port Write Waveforms........ 55
Parallel Slave Port Read Waveforms........ 55
Timer0 Block Diagram............................... 59
Timer0 Timing: Internal Clock/No
Prescale .................................................... 59
Timer0 Timing: Internal
Clock/Prescale 1:2 .................................... 60
Timer0 Interrupt Timing............................. 60
Timer0 Timing with External Clock............ 61
Block Diagram of the Timer0/WDT
2
Figure 11-25:
I C Waveforms for Reception
Figure 5-9:
Figure 5-10:
Figure 5-11:
(7-bit Address) .......................................... 95
2
Figure 11-26: I C Waveforms for Transmission
(7-bit Address) .......................................... 96
2
Figure 11-27: Operation of the I C Module in
Figure 5-12:
Figure 5-13:
Figure 7-1:
Figure 7-2:
IDLE_MODE, RCV_MODE or
XMIT_MODE ............................................ 98
TXSTA: Transmit Status and
Control Register (Address 98h) ................ 99
RCSTA: Receive Status and
Control Register (Address 18h) .............. 100
RX Pin Sampling Scheme. BRGH = 0
(PIC16C73/73A/74/74A)......................... 104
RX Pin Sampling Scheme, BRGH = 1
(PIC16C73/73A/74/74A)......................... 104
Figure 12-1:
Figure 12-2:
Figure 12-3:
Figure 12-4:
Figure 7-3:
Figure 7-4:
Figure 7-5:
Figure 7-6:
Prescaler................................................... 62
DS30390E-page 280
1997 Microchip Technology Inc.
PIC16C7X
Figure 12-5:
Figure 12-6:
RX Pin Sampling Scheme, BRGH = 1
(PIC16C73/73A/74/74A) ......................... 104
RX Pin Sampling Scheme,
Figure 17-4:
Reset, Watchdog Timer, Oscillator
Start-up Timer and Power-up Timer
Timing......................................................175
Brown-out Reset Timing ..........................175
Timer0 and Timer1 External
Clock Timings .........................................176
Capture/Compare/PWM
BRGH = 0 OR BRGH = 1 (
Figure 17-5:
Figure 17-6:
PIC16C76/77) ......................................... 105
USART Transmit Block Diagram............. 106
Asynchronous Master Transmission....... 107
Asynchronous Master Transmission
(Back to Back)......................................... 107
Figure 12-7:
Figure 12-8:
Figure 12-9:
Figure 17-7:
Timings (CCP1) .......................................177
SPI Mode Timing .....................................178
Figure 17-8:
Figure 17-9:
2
Figure 12-10: USART Receive Block Diagram.............. 108
Figure 12-11: Asynchronous Reception ........................ 108
Figure 12-12: Synchronous Transmission..................... 111
Figure 12-13: Synchronous Transmission
I C Bus Start/Stop Bits Timing.................179
2
Figure 17-10: I C Bus Data Timing................................180
Figure 17-11: A/D Conversion Timing............................182
Figure 18-1:
Figure 18-2:
Figure 18-3:
Figure 18-4:
Load Conditions.......................................188
External Clock Timing..............................189
CLKOUT and I/O Timing..........................190
Reset, Watchdog Timer,
(Through TXEN)...................................... 111
Figure 12-14: Synchronous Reception
(Master Mode, SREN)............................. 113
Figure 13-1:
Figure 13-2:
Figure 13-3:
Figure 13-4:
Figure 13-5:
Figure 13-6:
Figure 14-1:
ADCON0 Register (Address 1Fh)........... 117
ADCON1 Register (Address 9Fh)........... 118
A/D Block Diagram.................................. 119
Analog Input Model ................................. 120
A/D Transfer Function............................. 125
Flowchart of A/D Operation..................... 126
Configuration Word for
Oscillator Start-up Timer and Power-up Tim-
er Timing..................................................191
Timer0 and Timer1 External
Clock Timings .........................................192
Capture/Compare/PWM Timings
Figure 18-5:
Figure 18-6:
Figure 18-7:
(CCP1 and CCP2) ...................................193
Parallel Slave Port Timing
PIC16C73/74........................................... 129
Configuration Word for
PIC16C72/73A/74A/76/77....................... 130
Crystal/Ceramic Resonator
Operation (HS, XT or LP
OSC Configuration)................................. 131
External Clock Input Operation
(HS, XT or LP OSC Configuration) ......... 131
External Parallel Resonant Crystal
Oscillator Circuit...................................... 132
External Series Resonant Crystal
Oscillator Circuit..................................... 132
RC Oscillator Mode................................. 132
Simplified Block Diagram of On-chip
Reset Circuit............................................ 133
Brown-out Situations............................... 134
(PIC16C74)..............................................194
SPI Mode Timing .....................................195
Figure 14-2:
Figure 14-3:
Figure 18-8:
Figure 18-9:
2
I C Bus Start/Stop Bits Timing.................196
2
Figure 18-10: I C Bus Data Timing................................197
Figure 18-11: USART Synchronous Transmission
(Master/Slave) Timing..............................198
Figure 14-4:
Figure 14-5:
Figure 14-6:
Figure 18-12: USART Synchronous Receive
(Master/Slave) Timing..............................198
Figure 18-13: A/D Conversion Timing............................200
Figure 19-1:
Figure 19-2:
Figure 19-3:
Figure 19-4:
Load Conditions.......................................206
External Clock Timing..............................207
CLKOUT and I/O Timing..........................208
Reset, Watchdog Timer,
Figure 14-7:
Figure 14-8:
Oscillator Start-up Timer and
Power-up Timer Timing ...........................209
Brown-out Reset Timing ..........................209
Timer0 and Timer1 External
Clock Timings .........................................210
Capture/Compare/PWM Timings
(CCP1 and CCP2) ...................................211
Parallel Slave Port Timing
(PIC16C74A) ...........................................212
Figure 14-9:
Figure 19-5:
Figure 19-6:
Figure 14-10: Time-out Sequence on Power-up
(MCLR not Tied to VDD): Case 1............. 139
Figure 14-11: Time-out Sequence on Power-up
(MCLR Not Tied To VDD): Case 2.......... 139
Figure 14-12: Time-out Sequence on Power-up
(MCLR Tied to VDD)................................ 139
Figure 14-13: External Power-on Reset Circuit
(for Slow VDD Power-up)......................... 140
Figure 14-14: External Brown-out Protection
Circuit 1................................................... 140
Figure 14-15: External Brown-out Protection
Circuit 2................................................... 140
Figure 14-16: Interrupt Logic ......................................... 142
Figure 14-17: INT Pin Interrupt Timing.......................... 142
Figure 14-18: Watchdog Timer Block Diagram ............. 144
Figure 14-19: Summary of Watchdog
Timer Registers....................................... 144
Figure 14-20: Wake-up from Sleep Through
Interrupt................................................... 146
Figure 14-21: Typical In-Circuit Serial
Figure 19-7:
Figure 19-8:
Figure 19-9:
SPI Mode Timing .....................................213
2
Figure 19-10: I C Bus Start/Stop Bits Timing.................214
2
Figure 19-11: I C Bus Data Timing................................215
Figure 19-12: USART Synchronous Transmission
(Master/Slave) Timing..............................216
Figure 19-13: USART Synchronous Receive
(Master/Slave) Timing..............................216
Figure 19-14: A/D Conversion Timing............................218
Figure 20-1:
Figure 20-2:
Figure 20-3:
Figure 20-4:
Load Conditions.......................................225
External Clock Timing..............................226
CLKOUT and I/O Timing..........................227
Reset, Watchdog Timer,
Oscillator Start-up Timer and
Power-up Timer Timing ...........................228
Brown-out Reset Timing ..........................228
Timer0 and Timer1 External
Clock Timings ..........................................229
Capture/Compare/PWM Timings
Programming Connection ....................... 146
Figure 20-5:
Figure 20-6:
Figure 15-1:
Figure 17-1:
Figure 17-2:
Figure 17-3:
General Format for Instructions .............. 147
Load Conditions ...................................... 172
External Clock Timing ............................. 173
CLKOUT and I/O Timing......................... 174
Figure 20-7:
Figure 20-8:
(CCP1 and CCP2) ...................................230
Parallel Slave Port Timing
(PIC16C77).............................................231
1997 Microchip Technology Inc.
DS30390E-page 281
PIC16C7X
Figure 20-9:
SPI Master Mode Timing (CKE = 0)........ 232
Figure 21-27: Typical IDD vs. Frequency
(XT Mode, 25°C)..................................... 249
Figure 21-28: Maximum IDD vs. Frequency
(XT Mode, -40°C to 85°C)....................... 249
Figure 21-29: Typical IDD vs. Frequency
(HS Mode, 25°C) .................................... 250
Figure 21-30: Maximum IDD vs. Frequency
(HS Mode, -40°C to 85°C) ...................... 250
Figure 20-10: SPI Master Mode Timing (CKE = 1)........ 232
Figure 20-11: SPI Slave Mode Timing (CKE = 0).......... 233
Figure 20-12: SPI Slave Mode Timing (CKE = 1).......... 233
Figure 20-13: I C Bus Start/Stop Bits Timing................ 235
Figure 20-14: I C Bus Data Timing ............................... 236
2
2
Figure 20-15: USART Synchronous Transmission
(Master/Slave) Timing............................. 237
Figure 20-16: USART Synchronous Receive
(Master/Slave) Timing............................. 237
Figure 20-17: A/D Conversion Timing ........................... 239
Figure 21-1:
Figure 21-2:
Figure 21-3:
Figure 21-4:
Figure 21-5:
Figure 21-6:
Figure 21-7:
Figure 21-8:
Figure 21-9:
Typical IPD vs. VDD (WDT Disabled,
RC Mode)................................................ 241
Maximum IPD vs. VDD (WDT
Disabled, RC Mode)................................ 241
Typical IPD vs. VDD @ 25°C (WDT
Enabled, RC Mode)................................. 242
Maximum IPD vs. VDD (WDT
Enabled, RC Mode)................................. 242
Typical RC Oscillator
Frequency vs. VDD .................................. 242
Typical RC Oscillator
Frequency vs. VDD .................................. 242
Typical RC Oscillator
Frequency vs. VDD .................................. 242
Typical IPD vs. VDD Brown-out
Detect Enabled (RC Mode)..................... 243
Maximum IPD vs. VDD Brown-out
Detect Enabled
(85°C to -40°C, RC Mode) ...................... 243
Figure 21-10: Typical IPD vs. Timer1 Enabled
(32 kHz, RC0/RC1= 33 pF/33 pF,
RC Mode)................................................ 243
Figure 21-11: Maximum IPD vs. Timer1 Enabled
(32 kHz, RC0/RC1 = 33
pF/33 pF, 85°C to -40°C, RC Mode) ....... 243
Figure 21-12: Typical IDD vs. Frequency
(RC Mode @ 22 pF, 25°C)...................... 244
Figure 21-13: Maximum IDD vs. Frequency
(RC Mode @ 22 pF, -40°C to 85°C)........ 244
Figure 21-14: Typical IDD vs. Frequency
(RC Mode @ 100 pF, 25°C).................... 245
Figure 21-15: Maximum IDD vs. Frequency (
RC Mode @ 100 pF, -40°C to 85°C)....... 245
Figure 21-16: Typical IDD vs. Frequency
(RC Mode @ 300 pF, 25°C).................... 246
Figure 21-17: Maximum IDD vs. Frequency
(RC Mode @ 300 pF, -40°C to 85°C)...... 246
Figure 21-18: Typical IDD vs. Capacitance @
500 kHz (RC Mode) ................................ 247
Figure 21-19: Transconductance(gm) of
HS Oscillator vs. VDD .............................. 247
Figure 21-20: Transconductance(gm) of LP
Oscillator vs. VDD .................................... 247
Figure 21-21: Transconductance(gm) of XT
Oscillator vs. VDD .................................... 247
Figure 21-22: Typical XTAL Startup Time vs. VDD
(LP Mode, 25°C) ..................................... 248
Figure 21-23: Typical XTAL Startup Time vs. VDD
(HS Mode, 25°C)..................................... 248
Figure 21-24: Typical XTAL Startup Time vs. VDD
(XT Mode, 25°C) ..................................... 248
Figure 21-25: Typical Idd vs. Frequency
(LP Mode, 25°C) ..................................... 249
Figure 21-26: Maximum IDD vs. Frequency
(LP Mode, 85°C to -40°C) ....................... 249
DS30390E-page 282
1997 Microchip Technology Inc.
PIC16C7X
Table 12-8:
Table 12-9:
Table 12-10:
Table 12-11:
Table 13-1:
Table 13-2:
Table 13-3:
Registers Associated with Synchronous Mas-
ter Transmission ......................................111
Registers Associated with Synchronous Mas-
ter Reception ...........................................112
Registers Associated with
Synchronous Slave Transmission ...........115
Registers Associated with
Synchronous Slave Reception.................115
TAD vs. Device Operating
Frequencies.............................................121
Registers/Bits Associated with A/D,
PIC16C72 ................................................126
Summary of A/D Registers,
PIC16C73/73A/74/74A/76/77 ..................127
Ceramic Resonators................................131
Capacitor Selection for Crystal
Oscillator..................................................131
Time-out in Various Situations,
PIC16C73/74 ...........................................135
Time-out in Various Situations,
LIST OF TABLES
Table 1-1:
Table 3-1:
Table 3-2:
Table 3-3:
Table 4-1:
PIC16C7XX Family of Devces .................... 6
PIC16C72 Pinout Description ................... 13
PIC16C73/73A/76 Pinout Description....... 14
PIC16C74/74A/77 Pinout Description....... 15
PIC16C72 Special Function Register
Summary................................................... 23
PIC16C73/73A/74/74A Special
Table 4-2:
Table 4-3:
Function Register Summary...................... 25
PIC16C76/77 Special Function
Register Summary .................................... 27
PORTA Functions ..................................... 44
Summary of Registers Associated
Table 5-1:
Table 5-2:
Table 14-1:
Table 14-2:
with PORTA .............................................. 44
PORTB Functions ..................................... 46
Summary of Registers Associated
Table 5-3:
Table 5-4:
Table 14-3:
Table 14-4:
Table 14-5:
Table 14-6:
Table 14-7:
Table 14-8:
with PORTB .............................................. 47
PORTC Functions..................................... 48
Summary of Registers Associated
Table 5-5:
Table 5-6:
PIC16C72/73A/74A/76/77 .......................135
Status Bits and Their Significance,
PIC16C73/74 ...........................................135
Status Bits and Their Significance,
PIC16C72/73A/74A/76/77 .......................136
Reset Condition for Special
with PORTC .............................................. 49
PORTD Functions..................................... 50
Summary of Registers Associated
Table 5-7:
Table 5-8:
with PORTD .............................................. 50
PORTE Functions ..................................... 52
Summary of Registers Associated
Table 5-9:
Table 5-10:
Registers..................................................136
Initialization Conditions for all
with PORTE .............................................. 52
Registers Associated with
Table 5-11:
Registers..................................................136
Opcode Field Descriptions.......................147
PIC16CXX Instruction Set .......................148
Development Tools from Microchip .........166
Cross Reference of Device Specs
Parallel Slave Port..................................... 55
Registers Associated with Timer0............. 63
Capacitor Selection for the
Timer1 Oscillator....................................... 67
Registers Associated with Timer1
Table 15-1:
Table 15-2:
Table 16-1:
Table 17-1:
Table 7-1:
Table 8-1:
Table 8-2:
Table 9-1:
for Oscillator Configurations and
Frequencies of Operation
as a Timer/Counter ................................... 68
Registers Associated with
(Commercial Devices) .............................167
External Clock Timing
Requirements ..........................................173
CLKOUT and I/O Timing
Requirements ..........................................174
Reset, Watchdog Timer,
Oscillator Start-up Timer, Power-up
Timer, and brown-out Reset
Requirements ..........................................175
Timer0 and Timer1 External
Clock Requirements ................................176
Capture/Compare/PWM
Timer2 as a Timer/Counter ....................... 70
CCP Mode - Timer Resource.................... 71
Interaction of Two CCP Modules .............. 71
Example PWM Frequencies and
Resolutions at 20 MHz.............................. 75
Registers Associated with Capture,
Compare, and Timer1 ............................... 75
Registers Associated with PWM
and Timer2................................................ 76
Registers Associated with SPI
Table 17-2:
Table 17-3:
Table 17-4:
Table 10-1:
Table 10-2:
Table 10-3:
Table 10-4:
Table 10-5:
Table 11-1:
Table 11-2:
Table 17-5:
Table 17-6:
Operation .................................................. 82
Registers Associated with SPI
Requirements (CCP1) .............................177
SPI Mode Requirements..........................178
I C Bus Start/Stop Bits
Operation (PIC16C76/77) ......................... 88
I C Bus Terminology................................. 89
Data Transfer Received Byte
2
Table 17-7:
Table 17-8:
Table 11-3:
Table 11-4:
2
Requirements ..........................................179
I C Bus Data Requirements ....................180
Actions ...................................................... 94
Registers Associated with I C
2
2
Table 17-9:
Table 11-5:
Table 17-10:
A/D Converter Characteristics:
PIC16C72-04
(Commercial, Industrial, Extended)
PIC16C72-10
(Commercial, Industrial, Extended)
PIC16C72-20
(Commercial, Industrial, Extended)
PIC16LC72-04
(Commercial, Industrial)...........................181
A/D Conversion Requirements ................182
Cross Reference of Device
Specs for Oscillator Configurations
and Frequencies of Operation
(Commercial Devices) .............................183
Operation .................................................. 97
Baud Rate Formula................................. 101
Registers Associated with Baud
Rate Generator ....................................... 101
Baud Rates for Synchronous Mode ........ 102
Baud Rates for Asynchronous Mode
(BRGH = 0) ............................................. 102
Baud Rates for Asynchronous Mode
(BRGH = 1) ............................................. 103
Registers Associated with
Table 12-1:
Table 12-2:
Table 12-3:
Table 12-4:
Table 12-5:
Table 12-6:
Table 12-7:
Table 17-11:
Table 18-1:
Asynchronous Transmission................... 107
Registers Associated with
Asynchronous Reception ........................ 109
1997 Microchip Technology Inc.
DS30390E-page 283
PIC16C7X
Table 18-2:
Table 18-3:
Table 18-4:
external Clock Timing
Requirements.......................................... 189
CLKOUT and I/O Timing
Requirements.......................................... 190
Reset, Watchdog Timer, Oscillator
Start-up Timer and Power-up Timer
Requirements......................................... 191
Timer0 and Timer1 External Clock
Requirements.......................................... 192
Capture/Compare/PWM
Requirements (CCP1 and CCP2) ........... 193
Parallel Slave Port Requirements
Table 20-1:
Cross Reference of Device Specs
for Oscillator Configurations and
Frequencies of Operation
(Commercial Devices) ............................ 220
External Clock Timing
Requirements ......................................... 226
CLKOUT and I/O Timing
Requirements ......................................... 227
Reset, Watchdog Timer,
Oscillator Start-up Timer, Power-up
Timer, and brown-out reset
Requirements ......................................... 228
Timer0 and Timer1 External Clock
Requirements ......................................... 229
Capture/Compare/PWM
Table 20-2:
Table 20-3:
Table 20-4:
Table 18-5:
Table 18-6:
Table 18-7:
(PIC16C74) ............................................. 194
SPI Mode Requirements......................... 195
Table 20-5:
Table 20-6:
Table 20-7:
Table 18-8:
Table 18-9:
2
I C Bus Start/Stop Bits
Requirements.......................................... 196
Requirements (CCP1 and CCP2)........... 230
Parallel Slave Port Requirements
(PIC16C77)............................................. 231
SPI Mode requirements.......................... 234
2
Table 18-10:
Table 18-11:
I C Bus Data Requirements.................... 197
USART Synchronous Transmission
Requirements.......................................... 198
usart Synchronous Receive
Requirements.......................................... 198
A/D Converter Characteristics:................ 199
PIC16C73/74-04
(Commercial, Industrial)
PIC16C73/74-10
(Commercial, Industrial)
PIC16C73/74-20
Table 20-8:
Table 20-9:
Table 20-10:
Table 20-11:
2
Table 18-12:
Table 18-13:
I C Bus Start/Stop Bits Requirements.... 235
2
I C Bus Data Requirements ................... 236
USART Synchronous Transmission
Requirements ......................................... 237
USART Synchronous Receive
Requirements ......................................... 237
A/D Converter Characteristics: ............... 238
PIC16C76/77-04
Table 20-12:
Table 20-13:
(Commercial, Industrial)
PIC16LC73/74-04
(Commercial, Industrial, Extended)
PIC16C76/77-10
(Commercial, Industrial).......................... 199
A/D Conversion Requirements................ 200
Cross Reference of Device Specs
for Oscillator Configurations and
Frequencies of Operation
(Commercial Devices)............................. 201
External Clock Timing
Requirements.......................................... 207
CLKOUT and I/O Timing
Requirements.......................................... 208
Reset, Watchdog Timer, Oscillator
Start-up Timer, Power-up Timer,
and brown-out reset Requirements......... 209
Timer0 and Timer1 External Clock
Requirements.......................................... 210
Capture/Compare/PWM
(Commercial, Industrial, Extended)
PIC16C76/77-20
(Commercial, Industrial, Extended)
PIC16LC76/77-04
(Commercial, Industrial).......................... 238
A/D Conversion Requirements ............... 239
RC Oscillator Frequencies...................... 247
Capacitor Selection for Crystal
Oscillators............................................... 248
Pin Compatible Devices.......................... 271
Table 18-14:
Table 19-1:
Table 20-14:
Table 21-1:
Table 21-2:
Table 19-2:
Table 19-3:
Table 19-4:
Table E-1:
Table 19-5:
Table 19-6:
Table 19-7:
Requirements (CCP1 and CCP2) ........... 211
Parallel Slave Port Requirements
(PIC16C74A)........................................... 212
SPI Mode Requirements......................... 213
Table 19-8:
Table 19-9:
Table 19-10:
Table 19-11:
2
I C Bus Start/Stop Bits Requirements .... 214
2
I C Bus Data Requirements.................... 215
USART Synchronous Transmission
Requirements.......................................... 216
USART Synchronous Receive
Requirements.......................................... 216
A/D Converter Characteristics:................ 217
PIC16C73A/74A-04
Table 19-12:
Table 19-13:
(Commercial, Industrial, Extended)
PIC16C73A/74A-10
(Commercial, Industrial, Extended)
PIC16C73A/74A-20
(Commercial, Industrial, Extended)
PIC16LC73A/74A-04
(Commercial, Industrial).......................... 217
A/D Conversion Requirements................ 218
Table 19-14:
DS30390E-page 284
1997 Microchip Technology Inc.
PIC16C6X
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5. What deletions from the data sheet could be made without affecting the overall usefulness?
6. Is there any incorrect or misleading information (what and where)?
7. How would you improve this document?
8. How would you improve our software, systems, and silicon products?
DS30390E-page 286
1996 Microchip Technology Inc.
PIC16C7X
PIC16C7X PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery refer to the factory or the listed sales office.
Examples
PART NO. -XX X /XX XXX
Pattern:
QTP, SQTP, Code or Special Requirements
a)
PIC16C72 - 04/P 301
Commercial Temp.,
PDIP Package, 4 MHz,
normal VDD limits, QTP
pattern #301
Package:
JW
PQ
TQ
SO
SP
P
= Windowed CERDIP
= MQFP (Metric PQFP)
= TQFP (Thin Quad Flatpack)
= SOIC
= Skinny plastic dip
= PDIP
b)
c)
PIC16LC76 - 041/SO
Industrial Temp., SOIC
package, 4 MHz,
L
= PLCC
= SSOP
SS
extended VDD limits
Temperature
Range:
-
= 0°C to +70°C
= -40°C to +85°C
= -40°C to +125°C
I
PIC16C74A - 10E/P
Automotive Temp.,
PDIP package, 10 MHz,
normal VDD limits
E
Frequency
Range:
04
04
10
20
= 200 kHz (PIC16C7X-04)
= 4 MHz
= 10 MHz
= 20 MHz
Device
PIC16C7X
:VDD range 4.0V to 6.0V
PIC16C7XT :VDD range 4.0V to 6.0V (Tape/Reel)
PIC16LC7X :VDD range 2.5V to 6.0V
PIC16LC7XT :VDD range 2.5V to 6.0V (Tape/Reel)
* JW Devices are UV erasable and can be programmed to any device configuration. JW Devices meet the electrical requirement of
each oscillator type (including LC devices).
Sales and Support
Products supported by a preliminary Data Sheet may possibly have an errata sheet describing minor operational differences and
recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following:
1. The Microchip Website at www.microchip.com
2. Your local Microchip sales office (see following page)
3. The Microchip Corporate Literature Center U.S. FAX: (602) 786-7277
4. The Microchip’s Bulletin Board, via your local CompuServe number (CompuServe membership NOT required).
Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using.
For latest version information and upgrade kits for Microchip Development Tools, please call 1-800-755-2345 or 1-602-786-7302.
DS30390E-page 287
1997 Microchip Technology Inc.
WORLDWIDE SALES AND SERVICE
AMERICAS
AMERICAS (continued)
ASIA/PACIFIC (continued)
Corporate Office
Toronto
Singapore
Microchip Technology Inc.
Microchip Technology Inc.
Microchip Technology Singapore Pte Ltd.
200 Middle Road
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-786-7200 Fax: 480-786-7277
Technical Support: 480-786-7627
Web Address: http://www.microchip.com
5925 Airport Road, Suite 200
Mississauga, Ontario L4V 1W1, Canada
Tel: 905-405-6279 Fax: 905-405-6253
#07-02 Prime Centre
Singapore 188980
Tel: 65-334-8870 Fax: 65-334-8850
Taiwan, R.O.C
Microchip Technology Taiwan
10F-1C 207
Tung Hua North Road
Taipei, Taiwan, ROC
ASIA/PACIFIC
Hong Kong
Microchip Asia Pacific
Unit 2101, Tower 2
Atlanta
Microchip Technology Inc.
500 Sugar Mill Road, Suite 200B
Atlanta, GA 30350
Metroplaza
223 Hing Fong Road
Kwai Fong, N.T., Hong Kong
Tel: 852-2-401-1200 Fax: 852-2-401-3431
Tel: 886-2-2717-7175 Fax: 886-2-2545-0139
Tel: 770-640-0034 Fax: 770-640-0307
Boston
EUROPE
Microchip Technology Inc.
5 Mount Royal Avenue
Marlborough, MA 01752
Tel: 508-480-9990 Fax: 508-480-8575
Beijing
United Kingdom
Microchip Technology, Beijing
Unit 915, 6 Chaoyangmen Bei Dajie
Dong Erhuan Road, Dongcheng District
New China Hong Kong Manhattan Building
Beijing 100027 PRC
Arizona Microchip Technology Ltd.
505 Eskdale Road
Winnersh Triangle
Wokingham
Berkshire, England RG41 5TU
Tel: 44 118 921 5858 Fax: 44-118 921-5835
Denmark
Microchip Technology Denmark ApS
Regus Business Centre
Lautrup hoj 1-3
Ballerup DK-2750 Denmark
Tel: 45 4420 9895 Fax: 45 4420 9910
Chicago
Microchip Technology Inc.
333 Pierce Road, Suite 180
Itasca, IL 60143
Tel: 86-10-85282100 Fax: 86-10-85282104
India
Tel: 630-285-0071 Fax: 630-285-0075
Dallas
Microchip Technology Inc.
4570 Westgrove Drive, Suite 160
Addison, TX 75248
Microchip Technology Inc.
India Liaison Office
No. 6, Legacy, Convent Road
Bangalore 560 025, India
Tel: 91-80-229-0061 Fax: 91-80-229-0062
Tel: 972-818-7423 Fax: 972-818-2924
Dayton
Microchip Technology Inc.
Two Prestige Place, Suite 150
Miamisburg, OH 45342
Tel: 937-291-1654 Fax: 937-291-9175
Detroit
Microchip Technology Inc.
Tri-Atria Office Building
32255 Northwestern Highway, Suite 190
Farmington Hills, MI 48334
Tel: 248-538-2250 Fax: 248-538-2260
Japan
France
Microchip Technology Intl. Inc.
Benex S-1 6F
Arizona Microchip Technology SARL
Parc d’Activite du Moulin de Massy
43 Rue du Saule Trapu
3-18-20, Shinyokohama
Kohoku-Ku, Yokohama-shi
Kanagawa 222-0033 Japan
Tel: 81-45-471- 6166 Fax: 81-45-471-6122
Batiment A - ler Etage
91300 Massy, France
Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79
Germany
Arizona Microchip Technology GmbH
Gustav-Heinemann-Ring 125
D-81739 München, Germany
Tel: 49-89-627-144 0 Fax: 49-89-627-144-44
Korea
Microchip Technology Korea
168-1, Youngbo Bldg. 3 Floor
Samsung-Dong, Kangnam-Ku
Seoul, Korea
Tel: 82-2-554-7200 Fax: 82-2-558-5934
Shanghai
Microchip Technology
RM 406 Shanghai Golden Bridge Bldg.
2077 Yan’an Road West, Hong Qiao District
Shanghai, PRC 200335
Italy
Los Angeles
Arizona Microchip Technology SRL
Centro Direzionale Colleoni
Palazzo Taurus 1 V. Le Colleoni 1
20041 Agrate Brianza
Microchip Technology Inc.
18201 Von Karman, Suite 1090
Irvine, CA 92612
Tel: 949-263-1888 Fax: 949-263-1338
New York
Microchip Technology Inc.
150 Motor Parkway, Suite 202
Hauppauge, NY 11788
Tel: 631-273-5305 Fax: 631-273-5335
Milan, Italy
Tel: 39-039-65791-1 Fax: 39-039-6899883
Tel: 86-21-6275-5700 Fax: 86 21-6275-5060
11/15/99
San Jose
Microchip received QS-9000 quality system
certification for its worldwide headquarters,
design and wafer fabrication facilities in
Chandler and Tempe, Arizona in July 1999. The
Company’s quality system processes and
procedures are QS-9000 compliant for its
PICmicro® 8-bit MCUs, KEELOQ® code hopping
devices, Serial EEPROMs and microperipheral
products. In addition, Microchip’s quality
system for the design and manufacture of
development systems is ISO 9001 certified.
Microchip Technology Inc.
2107 North First Street, Suite 590
San Jose, CA 95131
Tel: 408-436-7950 Fax: 408-436-7955
All rights reserved. © 1999 Microchip Technology Incorporated. Printed in the USA. 11/99
Printed on recycled paper.
Information contained in this publication regarding device applications and the like is intended for suggestion only and may be superseded by updates. No representation or warranty is given and no liability is assumed
by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip’s products
as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. The Microchip
logo and name are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. All rights reserved. All other trademarks mentioned herein are the property of their respective companies.
1999 Microchip Technology Inc.
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