PIC16C770-04/SS [MICROCHIP]
18/20-Pin, 8-Bit CMOS Microcontrollers with 10/12-Bit A/D; 二十零分之一十八引脚， 8位CMOS微控制器10位/ 12位A / D
| 型号： | PIC16C770-04/SS |
| 厂家： | 
MICROCHIP |
| 描述： | 18/20-Pin, 8-Bit CMOS Microcontrollers with 10/12-Bit A/D |
| 文件： | 总200页 (文件大小：2885K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
PIC16C717/770/771
18/20-Pin, 8-Bit CMOS Microcontrollers with 10/12-Bit A/D
Microcontroller Core Features:
Pin Diagram
• High-performance RISC CPU
20-Pin PDIP, SOIC, SSOP
• Only 35 single word instructions to learn
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
RB3/CCP1/P1A
RB2/SCK/SCL
RA0/AN0
• All single cycle instructions except for program
branches which are two cycle
• Operating speed: DC - 20 MHz clock input
DC - 200 ns instruction cycle
RA1/AN1/LVDIN
RA7/OSC1/CLKIN
RA6/OSC2/CLKOUT
VDD
RA4/T0CKI
RA5/MCLR/VPP
VSS
AVSS
AVDD
Memory
A/D
A/D
RB7/T1OSI/P1D
RA2/AN2/VREF-/VRL
Device
Pins
Program Data
Resolution Channels
RB6/T1OSO/T1CKI/P1C
RB5/SDO/P1B
RA3/AN3/VREF+/VRH
RB0/AN4/INT
x14
2K
2K
4K
x8
12
11
9
PIC16C717
PIC16C770
PIC16C771
256 18, 20
10 bits
12 bits
12 bits
6
6
6
10
RB4/SDI/SDA
RB1/AN5/SS
256
256
20
20
Peripheral Features:
• Interrupt capability (up to 10 internal/external
interrupt sources)
• Timer0: 8-bit timer/counter with 8-bit prescaler
• Timer1: 16-bit timer/counter with prescaler,
can be incremented during sleep via external
crystal/clock
• Eight level deep hardware stack
• Direct, indirect and relative addressing modes
• Power-on Reset (POR)
• Timer2: 8-bit timer/counter with 8-bit period
register, prescaler and postscaler
• Power-up Timer (PWRT) and
Oscillator Start-up Timer (OST)
• Enhanced Capture, Compare, PWM (ECCP)
module
- 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
• Watchdog Timer (WDT) with its own on-chip RC
oscillator for reliable operation
• Selectable oscillator options:
- INTRC - Internal RC, dual speed (4MHz and
37KHz) dynamically switchable for power sav-
ings
- Enhanced PWM:
- Single, Half-Bridge and Full-Bridge output
modes
- ER - External resistor, dual speed (user
selectable frequency and 37KHz) dynami-
cally switchable for power savings
- Digitally programmable deadband delay
• Analog-to-Digital converter:
- PIC16C770/771 12-bit resolution
- PIC16C717 10-bit resolution
- EC - External clock
- HS - High speed crystal/resonator
- XT - Crystal/resonator
- LP - Low power crystal
• On-chip absolute bandgap voltage reference
generator
• Low-power, high-speed CMOS EPROM
technology
• Programmable Brown-out Reset (PBOR)
circuitry
• In-Circuit Serial Programming™ (ISCP)
• Programmable Low-Voltage Detection (PLVD)
circuitry
• Wide operating voltage range: 2.5V to 5.5V
• 15 I/O pins with individual control for:
- Direction (15 pins)
• Master Synchronous Serial Port (MSSP) with two
modes of operation:
- Digital/Analog input (6 pins)
- PORTB interrupt on change (8 pins)
- PORTB weak pull-up (8 pins)
- High voltage open drain (1 pin)
- 3-wire SPI™ (supports all 4 SPI modes)
- I2C™ compatible including master mode
support
• Program Memory Read (PMR) capability for look-
up table, character string storage and checksum
calculation purposes
• Commercial and Industrial temperature ranges
• Low-power consumption:
- < 2 mA @ 5V, 4 MHz
- 22.5 µA typical @ 3V, 32 kHz
- < 1 µA typical standby current
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 1
PIC16C717/770/771
Pin Diagrams
18-Pin PDIP, SOIC
20-Pin SSOP
RA0/AN0
1
2
20
19
18
17
16
15
14
13
RB3/CCP1/P1A
RB2/SCK/SCL
18
17
16
15
14
13
12
11
10
RA0/AN0
1
2
3
4
5
6
7
8
9
RB3/CCP1/P1A
RB2/SCK/SCL
RA1/AN1/LVDIN
RA1/AN1/LVDIN
RA4/T0CKI
3
RA7/OSC1/CLKIN
RA4/T0CKI
RA7/OSC1/CLKIN
RA6/OSC2/CLKOUT
VDD
RA5/MCLR/VPP
4
RA6/OSC2/CLKOUT
RA5/MCLR/VPP
(1)
(2)
VSS
VDD
5
VSS
(1)
(2)
VSS
VDD
6
RA2/AN2/VREF-/VRL
RB7/T1OSI/P1D
RA2/AN2/VREF-/VRL
RA3/AN3/VREF+/VRH
RB0/AN4/INT
RB7/T1OSI/P1D
7
RA3/AN3/VREF+/VRH
RB0/AN4/INT
RB6/T1OSO/T1CKI/P1C
RB5/SDO/P1B
8
RB6/T1OSO/T1CKI/P1C
RB5/SDO/P1B
9
12
11
RB1/AN5/SS
RB4/SDI/SDA
RB1/AN5/SS
10
RB4/SDI/SDA
Note 1: VSS pins 5 and 6 must be tied together.
2: VDD pins 15 and 16 must be tied together.
Key Features
PICmicroTM Mid-Range Reference Manual
(DS33023)
PIC16C717
PIC16C770
PIC16C771
Operating Frequency
Resets (and Delays)
DC - 20 MHz
DC - 20 MHz
DC - 20 MHz
POR, BOR, MCLR,
WDT (PWRT, OST)
POR, BOR, MCLR,
WDT (PWRT, OST)
POR, BOR, MCLR,
WDT (PWRT, OST)
Program Memory (14-bit words)
Data Memory (bytes)
Interrupts
2K
2K
4K
256
256
256
10
10
10
I/O Ports
Ports A,B
Ports A,B
Ports A,B
Timers
3
1
3
1
3
1
Enhanced Capture/Compare/PWM (ECCP)
modules
Serial Communications
12-bit Analog-to-Digital Module
10-bit Analog-to-Digital Module
Instruction Set
MSSP
MSSP
MSSP
6 input channels
6 input channels
6 input channels
35 Instructions
35 Instructions
35 Instructions
DS41120A-page 2
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Table of Contents
1.0 Device Overview................................................................................................................................................... 5
2.0 Memory Organization.......................................................................................................................................... 11
3.0 I/O Ports.............................................................................................................................................................. 27
4.0 Program Memory Read (PMR) ........................................................................................................................... 43
5.0 Timer0 Module.................................................................................................................................................... 47
6.0 Timer1 Module.................................................................................................................................................... 49
7.0 Timer2 Module.................................................................................................................................................... 53
8.0 Enhanced Capture/Compare/PWM(ECCP) Modules ......................................................................................... 55
9.0 Master Synchronous Serial Port (MSSP) Module............................................................................................... 67
10.0 Voltage Reference Module and Low-voltage Detect......................................................................................... 109
11.0 Analog-to-Digital Converter (A/D) Module ........................................................................................................ 113
12.0 Special Features of the CPU ............................................................................................................................ 125
13.0 Instruction Set Summary................................................................................................................................... 141
14.0 Development Support ....................................................................................................................................... 149
15.0 Electrical Characteristics................................................................................................................................... 155
16.0 DC and AC Characteristics Graphs and Tables ............................................................................................... 177
17.0 Packaging Information ...................................................................................................................................... 179
Revision History ........................................................................................................................................................ 189
Device Differences ..................................................................................................................................................... 189
Index .......................................................................................................................................................................... 191
On-Line Support.......................................................................................................................................................... 197
Reader Response....................................................................................................................................................... 198
PIC16C717/770/771 Product Identification System.................................................................................................... 199
To Our Valued Customers
Most Current Data Sheet
To obtain the most up-to-date version of this data sheet, please register at our Worldwide Web site at:
http://www.microchip.com
You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page.
The last character of the literature number is the version number. e.g., DS30000A is version A of document DS30000.
New Customer Notification System
Register on our web site (www.microchip.com/cn) to receive the most current information on our products.
Errata
An errata sheet may exist for current devices, describing minor operational differences (from the data sheet) and recommended
workarounds. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revi-
sion of silicon and revision of document to which it applies.
To determine if an errata sheet exists for a particular device, please check with one of the following:
•
•
•
Microchip’s Worldwide Web site; http://www.microchip.com
Your local Microchip sales office (see last page)
The Microchip Corporate Literature Center; U.S. FAX: (480) 786-7277
When contacting a sales office or the literature center, please specify which device, revision of silicon and data sheet (include liter-
ature number) you are using.
Corrections to this Data Sheet
We constantly strive to improve the quality of all our products and documentation. We have spent a great deal of time to ensure
that this document is 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:
•
•
Fill out and mail in the reader response form in the back of this data sheet.
E-mail us at webmaster@microchip.com.
We appreciate your assistance in making this a better document.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 3
PIC16C717/770/771
NOTES:
DS41120A-page 4
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
There are three devices (PIC16C717, PIC16C770 and
PIC16C771) covered by this datasheet. The
PIC16C717 device comes in 18/20-pin packages and
the PIC16C770/771 devices come in 20-pin packages.
1.0
DEVICE OVERVIEW
This document contains device-specific information.
Additional information may be found in the PICmicroTM
Mid-Range Reference Manual, (DS33023), which may
be obtained from your local Microchip Sales Represen-
tative or downloaded from the Microchip website. The
Reference Manual should be considered a comple-
mentary document to this data sheet, and is highly rec-
ommended reading for a better understanding of the
device architecture and operation of the peripheral
modules.
The following two figures are device block diagrams of
the PIC16C717 and the PIC16C770/771.
FIGURE 1-1: PIC16C717 BLOCK DIAGRAM
13
8
PORTA
Data Bus
RAM
Program Counter
EPROM
RA0/AN0
RA1/AN1/LVDIN
RA2/AN2/VREF-/VRL
RA3/AN3/VREF+/VRH
RA4/T0CKI
Program
Memory
8 Level Stack
File
Registers
2K x 14
(13-bit)
RA5/MCLR/VPP
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
256 x 8
Program
Bus
14
Program Memory
Read (PMR)
RAM
Addr(1)
9
Addr MUX
Instruction reg
PORTB
7
Indirect
Addr
RB0/AN4/INT
RB1/AN5/SS
Direct Addr
8
RB2/SCK/SCL
RB3/CCP1/P1A
RB4/SDI/SDA
RB5/SDO/P1B
RB6/T1OSO/T1CKI/P1C
RB7/T1OSI/P1O
FSR reg
STATUS reg
8
Internal
4MHz, 37KHz
and ER mode
3
MUX
Instruction
Decode &
Control
Power-up
Timer
ALU
Timing
Generation
Oscillator
Start-up Timer
8
OSC1/CLKIN
OSC2/CLKOUT
Power-on
Reset
W reg
VDD, VSS
Watchdog
Timer
Brown-out
Reset
10-bit
Bandgap
Low-voltage
ADC
Reference
Detect
Timer0
Timer1
Timer2
Master
Synchronous
Serial Port (MSSP)
Enhanced CCP
(ECCP1)
Note 1: Higher order bits are from the STATUS register.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 5
PIC16C717/770/771
FIGURE 1-2: PIC16C770/771 BLOCK DIAGRAM
13
8
PORTA
Data Bus
Program Counter
RA0/AN0
EPROM
RA1/AN1/LVDIN
RA2/AN2/VREF-/VRL
RA3/AN3/VREF+/VRH
RA4/T0CKI
RA5/MCLR/VPP
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
Program
RAM
File
Registers
Memory(2)
8 Level Stack
(13-bit)
256 x 8
Program
Bus
14
Program Memory
Read (PMR)
RAM
Addr(1)
9
Addr MUX
Instruction reg
PORTB
7
Indirect
Addr
Direct Addr
RB0/AN4/INT
RB1/AN5/SS
8
RB2/SCK/SCL
RB3/CCP1/P1A
RB4/SDI/SDA
RB5/SDO/P1B
RB6/T1OSO/T1CKI/P1C
RB7/T1OSI/P1O
FSR reg
STATUS reg
8
Internal
4MHz, 37KHz
and ER mode
3
MUX
Instruction
Decode &
Control
Power-up
Timer
ALU
Timing
Generation
Oscillator
Start-up Timer
8
OSC1/CLKIN
OSC2/CLKOUT
Power-on
Reset
W reg
VDD, VSS
Watchdog
Timer
Brown-out
Reset
AVDD
AVSS
12-bit
ADC
Bandgap
Reference
Low-voltage
Detect
Timer0
Timer1
Timer2
Master
Synchronous
Serial Port (MSSP)
Enhanced CCP
(ECCP1)
Note 1: Higher order bits are from the STATUS register.
2: Program memory for PIC16C770 is 2K x 14. Program memory for PIC16C771 is 4K x 14.
DS41120A-page 6
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 1-1:
PIC16C770/771 PINOUT DESCRIPTION
Input
Type
Output
Type
Name
Function
Description
RA0
AN0
ST
AN
ST
AN
AN
ST
AN
AN
CMOS
Bi-directional I/O
RA0/AN0
A/D input
RA1
CMOS
Bi-directional I/O
RA1/AN1/LVDIN
AN1
A/D input
LVDIN
RA2
LVD input reference
Bi-directional I/O
CMOS
AN2
A/D input
RA2/AN2/VREF-/VRL
RA3/AN3/VREF+/VRH
VREF-
VRL
Negative analog reference input
Internal voltage reference low output
Bi-directional I/O
AN
RA3
ST
AN
AN
CMOS
AN3
A/D input
VREF+
VRH
RA4
Positive analog reference input
Internal voltage reference high output
Bi-directional I/O
AN
OD
ST
ST
RA4/T0CKI
T0CKI
RA5
TMR0 clock input
ST
Input port
RA5/MCLR/VPP
MCLR
VPP
ST
Master clear
Power
ST
Programming voltage
Bi-directional I/O
RA6
CMOS
XTAL
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
RB0/AN4/INT
OSC2
CLKOUT
RA7
Crystal/resonator
CMOS
CMOS
FOSC/4 output
ST
XTAL
ST
Bi-directional I/O
OSC1
CLKIN
RB0
Crystal/resonator
External clock input/ER resistor connection
(1)
TTL
AN
CMOS
CMOS
Bi-directional I/O
AN4
A/D input
INT
ST
Interrupt input
(1)
RB1
TTL
AN
Bi-directional I/O
RB1/AN5/SS
AN5
A/D input
SS
ST
SSP slave select input
(1)
RB2
TTL
ST
CMOS
CMOS
OD
Bi-directional input
RB2/SCK/SCL
RB3/CCP1/P1A
RB4/SDI/SDA
SCK
SCL
Serial clock I/O for SPI
2
ST
Serial clock I/O for I C
(1)
RB3
TTL
ST
CMOS
CMOS
CMOS
CMOS
Bi-directional input
CCP1
P1A
Capture 1 input/Compare 1 output
PWM P1A output
(1)
RB4
TTL
ST
Bi-directional input
SDI
Serial data in for SPI
2
SDA
RB5
ST
OD
Serial data I/O for I C
(1)
ST
CMOS
CMOS
CMOS
Bi-directional I/O
RB5/SDO/P1B
SDO
P1B
Serial data out for SPI
PWM P1B output
Note 1: Bit programmable pull-ups.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 7
PIC16C717/770/771
TABLE 1-1:
PIC16C770/771 PINOUT DESCRIPTION (CONTINUED)
Input
Type
Output
Type
Name
Function
Description
(1)
RB6
T1OSO
T1CKI
P1C
TTL
CMOS
XTAL
Bi-directional I/O
Crystal/Resonator
TMR1 clock input
PWM P1C output
RB6/T1OSO/T1CKI/P1C
RB7/T1OSI/P1D
ST
CMOS
CMOS
(1)
RB7
TTL
Bi-directional I/O
T1OSI
P1D
XTAL
TMR1 crystal/resonator
PWM P1D output
CMOS
VSS
VDD
VSS
Power
Power
Power
Power
Ground reference for logic and I/O pins
Positive supply for logic and I/O pins
Ground reference for analog
VDD
AVSS
AVDD
AVSS
AVDD
Positive supply for analog
Note 1: Bit programmable pull-ups.
DS41120A-page 8
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 1-2:
PIC16C717 PINOUT DESCRIPTION
Input
Type
Output
Type
Name
Function
Description
RA0
AN0
ST
AN
ST
AN
AN
ST
AN
AN
CMOS
Bi-directional I/O
RA0/AN0
A/D input
RA1
CMOS
Bi-directional I/O
RA1/AN1/LVDIN
AN1
A/D input reference
LVD input reference
Bi-directional I/O
LVDIN
RA2
CMOS
AN2
A/D input
RA2/AN2/VREF-/VRL
RA3/AN3/VREF+/VRH
VREF-
VRL
Negative analog reference input
Internal voltage reference low output
Bi-directional I/O
AN
RA3
ST
AN
AN
CMOS
AN3
A/D input
VREF+
VRH
RA4
Positive analog reference high output
Internal voltage reference high output
Bi-directional I/O
AN
OD
ST
ST
RA4/T0CKI
T0CKI
RA5
TMR0 clock input
ST
Input port
RA5/MCLR/VPP
MCLR
VPP
ST
Master Clear
Power
ST
Programming Voltage
Bi-directional I/O
RA6
CMOS
XTAL
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
RB0/AN4/INT
OSC2
CLKOUT
RA7
Crystal/Resonator
CMOS
CMOS
FOSC/4 output
ST
XTAL
ST
Bi-directional I/O
OSC1
CLKIN
RB0
Crystal/Resonator
External clock input/ER resistor connection
(1)
TTL
AN
CMOS
CMOS
Bi-directional I/O
AN4
A/D input
INT
ST
Interrupt input
(1)
RB1
TTL
AN
Bi-directional I/O
RB1/AN5/SS
AN5
A/D input
SS
ST
SSP slave select input
(1)
RB2
TTL
ST
CMOS
CMOS
OD
Bi-directional input
RB2/SCK/SCL
RB3/CCP1/P1A
RB4/SDI/SDA
SCK
SCL
Serial clock I/O for SPI
2
ST
Serial clock I/O for I C
(1)
RB3
TTL
ST
CMOS
CMOS
CMOS
CMOS
Bi-directional input
CCP1
P1A
Capture 1 input/Compare 1 output
PWM P1A output
(1)
RB4
TTL
ST
ST
ST
Bi-directional input
SDI
Serial data in for SPI
2
SDA
RB5
OD
Serial data I/O for I C
(1)
CMOS
CMOS
CMOS
Bi-directional I/O
RB5/SDO/P1B
SDO
P1B
Serial data out for SPI
PWM P1B output
Note 1: Bit programmable pull-ups.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 9
PIC16C717/770/771
TABLE 1-2:
PIC16C717 PINOUT DESCRIPTION (CONTINUED)
Input
Type
Output
Type
Name
Function
Description
(1)
RB6
T1OSO
T1CKI
P1C
TTL
CMOS
XTAL
Bi-directional I/O
TMR1 Crystal/Resonator
TMR1 Clock input
RB6/T1OSO/T1CKI/P1C
RB7/T1OSI/P1D
ST
CMOS
CMOS
PWM P1C output
(1)
RB7
TTL
Bi-directional I/O
T1OSI
P1D
XTAL
TMR1 Crystal/Resonator
PWM P1D output
Ground
CMOS
VSS
VDD
VSS
Power
Power
VDD
Positive Supply
Note 1: Bit programmable pull-ups.
DS41120A-page 10
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 2-2: PROGRAM MEMORY MAP
AND STACK OF THE
2.0
MEMORY ORGANIZATION
There are two memory blocks in each of these
PICmicro® microcontrollers. Each block (Pro-
gram Memory and Data Memory) has its own bus,
so that concurrent access can occur.
PIC16C771
PC<12:0>
Additional information on device memory may be found
CALL, RETURN
RETFIE, RETLW
13
in the PICmicro
(DS33023).
Mid-Range Reference Manual,
Stack Level 1
Stack Level 2
2.1
Program Memory Organization
The PIC16C717/770/771 devices have a 13-bit pro-
gram counter capable of addressing an 8K x 14 pro-
gram memory space. The PIC16C717 and the
PIC16C770 have 2K x 14 words of program memory.
The PIC16C771 has 4K x 14 words of program mem-
ory. Accessing a location above the physically imple-
mented address will cause a wraparound.
Stack Level 8
Reset Vector
0000h
The reset vector is at 0000h and the interrupt vector is
at 0004h.
Interrupt Vector
Page 0
0004h
0005h
FIGURE 2-1: PROGRAM MEMORY MAP
AND STACK OF THE
On-chip
Program
Memory
07FFh
0800h
PIC16C717 AND PIC16C770
Page 1
0FFFh
1000h
PC<12:0>
CALL, RETURN
13
RETFIE, RETLW
Stack Level 1
Stack Level 2
3FFFh
2.2
Data Memory Organization
Stack Level 8
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.
Reset Vector
0000h
RP1 RP0
(STATUS<6:5>)
Interrupt Vector
Page 0
0004h
0005h
= 00 → Bank0
= 01 → Bank1
= 10 → Bank2
= 11 → Bank3
On-chip
Program
Memory
07FFh
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 frequently used special func-
tion registers from one bank are mirrored in another
bank for code reduction and quicker access.
3FFFh
2.2.1
GENERAL PURPOSE REGISTER FILE
The register file can be accessed either directly, or indi-
rectly, through the File Select Register FSR.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 11
PIC16C717/770/771
FIGURE 2-3: REGISTER FILE MAP
File
Address
File
Address
File
Address
File
Address
Indirect addr.(*)
TMR0
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
Indirect addr.(*)
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.(*)
OPTION_REG
PCL
80h
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
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
OPTION_REG
PCL
PCL
PCL
STATUS
FSR
STATUS
FSR
STATUS
FSR
STATUS
FSR
PORTA
PORTB
TRISA
TRISB
PORTB
TRISB
PCLATH
INTCON
PIR1
PCLATH
INTCON
PIE1
PCLATH
PCLATH
INTCON
PMCON1
INTCON
PMDATL
PIR2
PMADRL
PMDATH
PMADRH
PIE2
TMR1L
TMR1H
T1CON
TMR2
PCON
SSPCON2
PR2
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON
SSPADD
SSPSTAT
WPUB
IOCB
P1DEL
REFCON
LVDCON
ANSEL
ADRESL
ADCON1
ADRESH
ADCON0
A0h
1A0h
General
Purpose
Register
80 Bytes
General
Purpose
Register
General
Purpose
Register
80 Bytes
96 Bytes
1EFh
1F0h
EFh
F0h
6Fh
70h
accesses
70h - 7Fh
accesses
70h - 7Fh
accesses
70h-7Fh
7Fh
FFh
17Fh
1FFh
Bank 0
Bank 1
Bank 2
Bank 3
Unimplemented data memory locations, read as ’0’.
Not a physical register.
*
DS41120A-page 12
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
2.2.2
SPECIAL FUNCTION REGISTERS
The special function registers can be classified into two
sets; core (CPU) and peripheral. Those registers asso-
ciated with the core functions are described in detail in
this section. Those related to the operation of the
peripheral features are described in detail in that
peripheral feature section.
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. A list of these registers is
given in Table 2-1.
TABLE 2-1:
PIC16C717/770/771 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(3)
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
xxxx 0000 uuuu 0000
xxxx xx00 uuuu uu00
02h(3)
03h(3)
04h(3)
05h
Program Counter's (PC) Least Significant Byte
STATUS
FSR
IRP
RP1
RP0
TO
PD
Z
DC
C
Indirect data memory address pointer
PORTA
PORTB
—
RA7
RA6
RB6
RA5
RB5
RA4
RB4
RA3
RB3
RA2
RB2
RA1
RB1
RA0
RB0
06h
RB7
07h
Unimplemented
Unimplemented
Unimplemented
—
—
—
—
—
—
—
08h
—
09h
—
0Ah(1,3) PCLATH
—
—
T0IE
—
Write Buffer for the upper 5 bits of the Program Counter
---0 0000 ---0 0000
0000 000x 0000 000u
0Bh(3)
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
—
INTE
—
RBIE
SSPIF
BCLIF
T0IF
CCP1IF
—
INTF
TMR2IF
—
RBIF
TMR1IF -0-- 0000 -0-- 0000
PIR2
LVDIF
—
—
—
0--- 0--- 0--- 0---
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
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
—
—
T1CKPS1
T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
0000 0000 0000 0000
Timer2 module’s register
TOUTPS3 TOUTPS2
—
TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
Synchronous Serial Port Receive Buffer/Transmit Register
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
Capture/Compare/PWM Register1 (LSB)
Capture/Compare/PWM Register1 (MSB)
PWM1M1 PWM1M0
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
Unimplemented
DC1B1
DC1B0
CCP1M3 CCP1M2 CCP1M1 CCP1M0 0000 0000 0000 0000
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
ADRESH
ADCON0
A/D High Byte Result Register
ADCS1 ADCS0 CHS2
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
CHS1
CHS0
GO/DONE
CHS3
ADON
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: These registers can be addressed from any bank.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 13
PIC16C717/770/771
TABLE 2-1:
Address Name
Bank 1
PIC16C717/770/771 SPECIAL FUNCTION REGISTER SUMMARY (CONTINUED)
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(3)
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
1111 1111 1111 1111
1111 1111 1111 1111
OPTION_REG RBPU
INTEDG
Program Counter’s (PC) Least Significant Byte
IRP RP1 RP0 TO
T0CS
T0SE
PSA
PS2
PS1
PS0
82h(3)
83h(3)
84h(3)
85h
PCL
STATUS
FSR
TRISA
TRISB
—
PD
Z
DC
C
Indirect data memory address pointer
PORTA Data Direction Register
PORTB Data Direction Register
Unimplemented
86h
87h
—
—
—
—
—
—
88h
—
Unimplemented
89h
—
Unimplemented
8Ah(1,3) PCLATH
—
GIE
—
—
PEIE
ADIE
—
—
T0IE
—
Write Buffer for the upper 5 bits of the Program Counter
---0 0000 ---0 0000
0000 000x 0000 000u
8Bh(3)
8Ch
8Dh
8Eh
8Fh
90h
91h
92h
93h
94h
95h
96h
97h
98h
99h
9Ah
9Bh
9Ch
9Dh
9Eh
9Fh
INTCON
PIE1
INTE
—
RBIE
SSPIE
BCLIE
OSCF
T0IF
CCP1IE
—
INTF
TMR2IE
—
RBIF
TMR1IE -0-- 0000 -0-- 0000
PIE2
LVDIE
—
—
—
—
0--- 0--- 0--- 0---
---- 1-qq ---- 1-uu
PCON
—
—
—
—
—
POR
BOR
Unimplemented
Unimplemented
—
—
—
—
—
SSPCON2
PR2
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
R/W
RSEN
UA
SEN
BF
0000 0000 0000 0000
1111 1111 1111 1111
0000 0000 0000 0000
0000 0000 0000 0000
1111 1111 1111 1111
1111 0000 1111 0000
0000 0000 0000 0000
Timer2 Period Register
SSPADD
SSPSTAT
WPUB
IOCB
Synchronous Serial Port (I2C mode) Address Register
SMP
CKE
D/A
P
S
PORTB Weak Pull-up Control
PORTB Interrupt on Change Control
PWM 1 Delay value
P1DEL
—
Unimplemented
—
—
—
—
—
—
—
Unimplemented
—
Unimplemented
REFCON
LVDCON
ANSEL
ADRESL
ADCON1
VRHEN
—
VRLEN
—
VRHOEN
BGST
VRLOEN
LVDEN
—
—
—
—
0000 ---- 0000 ----
--00 0101 --00 0101
1111 1111 1111 1111
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
LVV3
LVV2
LVV1
LVV0
Analog Channel Select
A/D Low Byte Result Register
ADFM VCFG2 VCFG1
VCFG0
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: These registers can be addressed from any bank.
DS41120A-page 14
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 2-1:
Address Name
Bank 2
PIC16C717/770/771 SPECIAL FUNCTION REGISTER SUMMARY (CONTINUED)
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(3)
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
Timer0 module’s register
0000 0000
xxxx xxxx
0000 0000
0001 1xxx
xxxx xxxx
0000 0000
uuuu uuuu
0000 0000
000q quuu
uuuu uuuu
101h
TMR0
PCL
102h(3)
103h(3)
Program Counter's (PC) Least Significant Byte
STATUS
FSR
IRP
RP1
RP0
TO
PD
Z
DC
C
104h(3)
105h
106h
107h
108h
109h
Indirect data memory address pointer
Unimplemented
—
PORTB
—
—
—
PORTB Data Latch when written: PORTB pins when read
xxxx xx00
uuuu uu00
Unimplemented
Unimplemented
Unimplemented
—
—
—
—
—
—
—
—
10Ah(1,3)
PCLATH
INTCON
—
—
—
Write Buffer for the upper 5 bits of the Program Counter
INTE RBIE T0IF INTF RBIF
---0 0000
---0 0000
10Bh(3)
10Ch
10Dh
10Eh
10Fh
GIE
PEIE
T0IE
0000 000x
0000 000u
PMDATL
PMADRL
PMDATH
PMADRH
Program memory read data low
xxxx xxxx
xxxx xxxx
--xx xxxx
---- xxxx
uuuu uuuu
uuuu uuuu
--uu uuuu
---- uuuu
Program memory read address low
—
—
—
—
Program memory read data high
Program memory read address high
—
—
110h-
11Fh
—
Unimplemented
—
—
Bank 3
180h(3)
181h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
0000 0000
1111 1111
0000 0000
0000 0000
1111 1111
0000 0000
OPTION_REG RBPU
INTEDG
Program Counter's (PC) Least Significant Byte
IRP RP1 RP0 TO
T0CS
T0SE
PSA
PS2
PS1
PS0
182h(3)
183h(3)
PCL
STATUS
PD
Z
DC
C
0001 1xxx
000q quuu
184h(3)
185h
186h
187h
188h
189h
FSR
—
Indirect data memory address pointer
Unimplemented
xxxx xxxx
uuuu uuuu
—
1111 1111
—
—
1111 1111
—
TRISB
—
PORTB Data Direction Register
Unimplemented
—
Unimplemented
—
—
—
Unimplemented
—
—
18Ah(1,3)
Write Buffer for the upper 5 bits of the Program Counter
PCLATH
—
—
—
---0 0000
---0 0000
18Bh(3)
18Ch
INTCON
GIE
PEIE
—
T0IE
—
INTE
—
RBIE
—
T0IF
—
INTF
—
RBIF
RD
0000 000x
1--- ---0
0000 000u
1--- ---0
PMCON1
Reserved
18Dh-
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: These registers can be addressed from any bank.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 15
PIC16C717/770/771
2.2.2.1
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).
The STATUS register, shown in Register 2-1, contains
the arithmetic status of the ALU, the RESET status and
the bank select bits for data memory.
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 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 2: The C and DC bits operate as a borrow and
digit borrow bit, respectively, in subtraction.
See the SUBLWand SUBWFinstructions for
examples.
REGISTER 2-1: STATUS REGISTER (STATUS: 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: RP<1:0>: 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 sec-
ond operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low order bit of
the source register.
DS41120A-page 16
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
2.2.2.2
OPTION_REG REGISTER
Note: To achieve a 1:1 prescaler assignment for
the TMR0 register, assign the prescaler to
the Watchdog Timer.
The OPTION_REG register is a readable and writable
register, which contains various control bits to configure
the TMR0 prescaler/WDT postscaler (single assign-
able register known also as the prescaler), the External
INT Interrupt, TMR0 and the weak pull-ups on PORTB.
REGISTER 2-2: OPTION REGISTER (OPTION_REG: 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:
bit 6:
bit 5:
bit 4:
bit 3:
RBPU: PORTB Pull-up Enable bit(1)
1= PORTB weak pull-ups are disabled
0= PORTB weak pull-ups are enabled by the WPUB register
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: PS<2:0>: 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
Note 1: Individual weak pull-up on RB pins can be enabled/disabled from the weak pull-up PORTB Register
(WPUB).
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 17
PIC16C717/770/771
2.2.2.3
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>). User soft-
ware should ensure the appropriate inter-
rupt flag bits are clear prior to enabling an
interrupt.
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.
REGISTER 2-3: INTERRUPT CONTROL REGISTER (INTCON: 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
bit 7:
bit 6:
bit 5:
bit 4:
bit 3:
bit 2:
bit 1:
bit 0:
GIE: Global Interrupt Enable bit
1= Enables all un-masked interrupts
0= Disables all interrupts
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)
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)
1= At least one of the RB<7:0> pins changed state (must be cleared in software)
0= None of the RB<7:0> pins have changed state
Note 1: Individual RB pin interrupt on change can be enabled/disabled from the Interrupt on Change PORTB register (IOCB).
DS41120A-page 18
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
2.2.2.4
PIE1 REGISTER
Note: Bit PEIE (INTCON<6>) must be set to
enable any peripheral interrupt.
This register contains the individual enable bits for the
peripheral interrupts.
REGISTER 2-4: PERIPHERAL INTERRUPT ENABLE REGISTER 1 (PIE1: 8Ch)
U-0
R/W-0
U-0
U-0
R/W-0
R/W-0
R/W-0
TMR2IE TMR1IE
bit0
R/W-0
—
ADIE
—
—
SSPIE
CCP1IE
R
W
U
= Readable bit
= Writable bit
= Unimplemented bit,
read as ‘0’
bit7
- 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
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 19
PIC16C717/770/771
2.2.2.5
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.
This register contains the individual flag bits for the
peripheral interrupts.
REGISTER 2-5: PERIPHERAL INTERRUPT REGISTER 1 (PIR1: 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
bit7
U
= Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
Unimplemented: Read as ‘0’.
bit 6:
ADIF: A/D Converter Interrupt Flag bit
1= An A/D conversion completed
0= The A/D conversion is not complete
bit 5-4: Unimplemented: Read as ‘0’.
bit 3: SSPIF: Synchronous Serial Port (SSP) Interrupt Flag
1= The SSP interrupt condition has occurred, and must be cleared in software before returning from the
interrupt service routine. The conditions that will set this bit are:
SPI
A transmission/reception has taken place.
I2C Slave / Master
A transmission/reception has taken place.
I2C Master
The initiated start condition was completed by the SSP module.
The initiated stop condition was completed by the SSP module.
The initiated restart condition was completed by the SSP module.
The initiated acknowledge condition was completed by the SSP module.
A start condition occurred while the SSP module was idle (Multimaster system).
A stop condition occurred while the SSP module was idle (Multimaster system).
0= No SSP interrupt condition has occurred.
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
DS41120A-page 20
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
2.2.2.6
PIE2 REGISTER
This register contains the individual enable bits for the
SSP bus collision and low voltage detect interrupts.
REGISTER 2-6: PERIPHERAL INTERRUPT REGISTER 2 (PIE2: 8Dh)
R/W-0
LVDIE
U-0
U-0
U-0
R/W-0
U-0
U-0
U-0
—
—
—
BCLIE
—
—
—
R
W
U
= Readable bit
= Writable bit
= Unimplemented bit,
read as ‘0’
bit7
bit0
- n = Value at POR reset
bit 7:
LVDIE: Low-voltage Detect Interrupt Enable bit
1= LVD Interrupt is enabled
0= LVD Interrupt is disabled
bit 6-4: Unimplemented: Read as ’0’
bit 3:
BCLIE: Bus Collision Interrupt Enable bit
1= Bus Collision interrupt is enabled
0= Bus Collision interrupt is disabled
bit 2-0: Unimplemented: Read as ’0’
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 21
PIC16C717/770/771
.
2.2.2.7
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.
This register contains the SSP Bus Collision and low-
voltage detect interrupt flag bits.
REGISTER 2-7: PERIPHERAL INTERRUPT REGISTER 2 (PIR2: 0Dh)
R/W-0
LVDIF
U-0
U-0
U-0
R/W-0
U-0
U-0
U-0
—
—
—
BCLIF
—
—
—
R
W
U
= Readable bit
= Writable bit
= Unimplemented bit,
read as ‘0’
bit7
bit0
- n = Value at POR reset
bit 7:
LVDIF: Low-voltage Detect Interrupt Flag bit
1= The supply voltage has fallen below the specified LVD voltage (must be cleared in software)
0= The supply voltage is greater than the specified LVD voltage
bit 6-4: Unimplemented: Read as ’0’
bit 3:
BCLIF: Bus Collision Interrupt Flag bit
1= A bus collision has occurred while the SSP module configured in I2C Master was transmitting
(must be cleared in software)
0= No bus collision occurred
bit 2-0: Unimplemented: Read as ’0’
DS41120A-page 22
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
2.2.2.8
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).
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.
The PCON register also contains the frequency select
bit of the INTRC or ER oscillator.
REGISTER 2-8: POWER CONTROL REGISTER (PCON: 8Eh)
U-0
U-0
U-0
U-0
R/W-1
U-0
R/W-q
R/W-q
—
—
—
—
OSCF
—
POR
BOR
R
W
U
= Readable bit
= Writable bit
= Unimplemented bit,
read as ‘0’
bit7
bit0
- n = Value at POR reset
bit 7-4,2:Unimplemented: Read as ’0’
bit 3:
OSCF: Oscillator speed
INTRC Mode
1= 4 MHz nominal
0= 37 KHz nominal
ER Mode
1= Oscillator frequency depends on the external resistor value on the OSC1 pin.
0= 37 KHz nominal
All other modes
x= Ignored
bit 1:
bit 0:
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)
BOR: 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)
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 23
PIC16C717/770/771
2.3
PCL and PCLATH
2.4
Stack
The program counter (PC) specifies the address of the
instruction to fetch for execution. The PC is 13 bits
wide. The low byte is called the PCL register. This reg-
ister is readable and writable. The high byte is called
the PCH register. This register contains the PC<12:8>
bits and is not directly readable or writable. All updates
to the PCH register occur through the PCLATH register.
The stack allows a combination of up to 8 program calls
and interrupts to occur. The stack contains the return
address from this branch in program execution.
Mid-range devices have 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 modified when the stack is PUSHed or
POPed.
2.3.1
PROGRAM MEMORY PAGING
PIC16C717/770/771 devices are capable of address-
ing a continuous 8K word block of program memory.
The CALLand GOTOinstructions 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 CALL or GOTO instruc-
tion, the user must ensure that the page select bits are
programmed so that the desired program memory
page is addressed. A return instruction pops a PC
address off the stack onto the PC register. Therefore,
manipulation of the PCLATH<4:3> bits are not required
for the return instructions (which POPs the address
from the stack).
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).
DS41120A-page 24
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
The INDF register is not a physical register. Address-
ing INDF actually addresses the register whose
address is contained in the FSR register (FSR is a
pointer). This is indirect addressing.
EXAMPLE 2-1: HOW TO CLEAR RAM
USING INDIRECT
ADDRESSING
movlw 0x20 ;initialize pointer
Reading INDF itself indirectly (FSR = 0) will produce
00h. Writing to the INDF register indirectly results in a
no-operation (although STATUS bits may be affected).
movwf FSR
; to RAM
INDF ;clear INDF register
FSR ;inc pointer
NEXT
clrf
incf
btfss FSR,4 ;all done?
A simple program to clear RAM locations 20h-2Fh
using indirect addressing is shown in Example 2-1.
goto
NEXT ;NO, clear next
CONTINUE
:
;YES, continue
An effective 9-bit address is obtained by concatenating
the 8-bit FSR register and the IRP bit (STATUS<7>), as
shown in Figure 2-4.
FIGURE 2-4: 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
(1)
7Fh
Bank 0
FFh
Bank 1
17Fh
Bank 2
1FFh
Bank 3
Note 1: For register file map detail see Figure 2-3.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 25
PIC16C717/770/771
NOTES:
DS41120A-page 26
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
present on a pin, the pin must be configured as an ana-
log input to prevent unnecessary current draw from the
power supply. The Analog Select Register (ANSEL)
allows the user to individually select the digital/analog
mode on these pins. When the analog mode is active,
the port pin will always read 0.
3.0
I/O PORTS
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.
Additional information on I/O ports may be found in the
Note 1: On a Power-on Reset, the ANSEL register
configures these mixed-signal pins as
analog mode.
PICmicro™
(DS33023).
Mid-Range
Reference
Manual,
3.1
I/O Port Analog/Digital Mode
2: If a pin is configured as analog mode, the
pin will always read '0', even if the digital
output is active.
The PIC16C717/770/771 have two I/O ports: PORTA
and PORTB. Some of these port pins are mixed-signal
(can be digital or analog). When an analog signal is
REGISTER 3-1: ANALOG SELECT REGISTER (ANSEL: 9Dh)
R/W-1
R/W-1
R/W-1
ANS5
R/W-1
ANS4
R/W-1
ANS3
R/W-1
ANS2
R/W-1
ANS1
R/W-1
ANS0
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as
‘0’
bit7
bit0
-n = Value at POR reset
bit 7-6: Reserved: Do not use
bit 5-0: ANS<5:0>: Analog Select between analog or digital function on pins AN<5:0>, respectively.
0= Digital I/O. Pin is assigned to port or special function.
1= Analog Input. Pin is assigned as analog input.
Note: Setting a pin to an analog input disables digital inputs and any pull-up that may be present. The corre-
sponding TRIS bit should be set to input mode when using pins as analog inputs.
these pins as analog input/output, the ANSEL register
must have the proper value to individually select the
analog mode of the corresponding pins.
3.2
PORTA and the TRISA Register
PORTA is a 8-bit wide bi-directional port. The corre-
sponding data direction register is TRISA. Setting a
TRISA bit (=1) will make the corresponding PORTA pin
an input, i.e., put the corresponding output driver in a
hi-impedance mode. Clearing a TRISA bit (=0) will
make the corresponding PORTA pin an output, i.e., put
the contents of the output latch on the selected pin.
Note: Upon reset, the ANSEL register configures
the RA<3:0> pins as analog inputs. All
RA<3:0> pins will read as ’0’.
Pin RA4 is multiplexed with the Timer0 module clock
input to become the RA4/T0CKI pin. The RA4/T0CKI
pin is a Schmitt Trigger input and an open drain output.
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.
Pin RA5 is multiplexed with the device reset (MCLR)
and programming input (VPP) functions. The RA5/
MCLR/VPP input only pin has a Schmitt Trigger input
buffer. All other RA port pins have Schmitt Trigger input
buffers and full CMOS output buffers.
Pins RA<3:0> are multiplexed with analog functions,
such as analog inputs to the A/D converter, analog
VREF inputs, and the on-board bandgap reference out-
puts. When the analog peripherals are using any of
Pins RA6 and RA7 are multiplexed with the oscillator
input and output functions.
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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 27
PIC16C717/770/771
EXAMPLE 3-1: INITIALIZING PORTA
BCF
STATUS, RP0 ; Select Bank 0
CLRF
PORTA ; Initialize PORTA by
; clearing output
; data latches
BSF
STATUS, RP0 ; Select Bank 1
MOVLW 0Fh
; Value used to
; initialize data
; direction
MOVWF TRISA
; Set RA<3:0> as inputs
; RA<7:4> as outputs. RA<7:6>availability depends on oscillator selection.
; Set RA<1:0> as analog inputs, RA<7:2> are digital I/O
MOVLW 03
MOVWF ANSEL
BCF
STATUS, RP0 ; Return to Bank 0
FIGURE 3-1: BLOCK DIAGRAM OF RA0/AN0, RA1/AN1/LVDIN
Data Latch
Data
Bus
D
Q
VDD
VDD
P
WR
PORT
Q
CK
TRIS Mode
N
D
Q
WR
TRIS
VSS
VSS
Q
CK
RD
TRIS
Analog Select
Schmitt
Trigger
D
Q
WR
ANSEL
Q
CK
Q
D
EN
RD
PORT
To A/D Converter input or LVD Module input
DS41120A-page 28
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 3-2: BLOCK DIAGRAM OF RA2/AN2/VREF-/VRL AND RA3/AN3/VREF+/VRH
Data Latch
D
Data
Bus
Q
VDD
VDD
P
WR
PORT
Q
CK
TRIS Mode
N
D
Q
WR
TRIS
VSS
VSS
Q
CK
RD
TRIS
Analog Select
D
Q
Schmitt
Trigger
WR
ANSEL
Q
CK
Q
D
EN
RD
PORT
To A/D Converter input
and Vref+, Vref- inputs
VRH, VRL outputs
(From Vref-LVD-BOR Module)
VRH, VRL output enable
Sense input for
VRH, VRL amplifier
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 29
PIC16C717/770/771
FIGURE 3-3: BLOCK DIAGRAM OF RA4/T0CKI
Data Latch
Data
Bus
D
Q
WR
Port
Q
CK
TRIS Latch
N
D
Q
WR
TRIS
VSS
Q
CK
VSS
RD
TRIS
Schmitt Trigger
Input Buffer
Q
D
EN
RD
PORT
TMR0 clock input
DS41120A-page 30
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 3-4: BLOCK DIAGRAM OF RA5/MCLR/VPP
To MCLR Circuit
MCLR Filter
Program Mode
HV Detect
Data
Bus
VSS
RD
TRIS
VSS
Schmitt
Trigger
Q
D
EN
RD PORT
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 31
PIC16C717/770/771
FIGURE 3-5: BLOCK DIAGRAM OF RA6/OSC2/CLKOUT PIN
INTRC or ER with CLKOUT
From OSC1
CLKOUT (FOSC/4)
Oscillator
Circuit
1
0
VDD
Data
Bus
VDD
P
D
Q
Q
WR
PORTA
CK
VSS
INTRC or ER
Data Latch
D
Q
N
WR
TRISA
CK
Q
INTRC or ER without CLKOUT
INTRC or ER with CLKOUT
TRIS Latch
VSS
Schmitt Trigger
Input Buffer
RD TRISA
Q
D
EN
RD PORTA
DS41120A-page 32
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 3-6: BLOCK DIAGRAM OF RA7/OSC1/CLKIN PIN
To OSC2
Oscillator
Circuit
VDD
To Chip Clock Drivers
VDD
Schmitt Trigger
Input Buffer
Data
Bus
D
Q
Q
EC Mode
P
WR
PORTA
CK
Data Latch
D
Q
N
WR
TRISA
CK
Q
TRIS Latch
INTRC
VSS
INTRC
RD TRISA
Schmitt Trigger
Input Buffer
Q
D
EN
RD PORTA
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 33
PIC16C717/770/771
TABLE 3-1:
PORTA FUNCTIONS
Input
Type
Output
Type
Name
Function
Description
RA0
AN0
ST
AN
ST
AN
AN
ST
AN
AN
CMOS
Bi-directional I/O
A/D input
RA0/AN0
RA1
CMOS
Bi-directional I/O
A/D input
RA1/AN1/LVDIN
AN1
LVDIN
RA2
LVD input reference
Bi-directional I/O
A/D input
CMOS
AN2
RA2/AN2/VREF-/VRL
RA3/AN3/VREF+/VRH
VREF-
VRL
Negative analog reference input
Internal voltage reference low output
Bi-directional I/O
AN
RA3
ST
AN
AN
CMOS
AN3
A/D input
VREF+
VRH
Positive analog reference input
Internal voltage reference high output
Bi-directional I/O
AN
OD
RA4
ST
ST
RA4/T0CKI
T0CKI
RA5
TMR0 clock input
ST
Input port
RA5/MCLR/VPP
MCLR
VPP
ST
Master clear
Power
ST
Programming voltage
Bi-directional I/O
RA6
CMOS
XTAL
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
OSC2
CLKOUT
RA7
Crystal/resonator
CMOS
CMOS
FOSC/4 output
ST
XTAL
ST
Bi-directional I/O
OSC1
CLKIN
Crystal/resonator
External clock input/ER resistor connection
DS41120A-page 34
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 3-2:
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
xxxx 0000 uuuu 0000
1111 1111 1111 1111
05h
85h
9Dh
PORTA
TRISA
ANSEL
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
PORTA Data Direction Register
ANS5 ANS4
ANS3
ANS2
ANS1
ANS0 1111 1111 1111 1111
Legend: x= unknown, u= unchanged, -= unimplemented locations read as ’0’. Shaded cells are not used by PORTA.
enables the weak pull-up resistors. The weak pull-up is
automatically turned off when the port pin is configured
as an output. The pull-ups are disabled on a Power-on
Reset.
3.3
PORTB and the TRISB Register
PORTB is an 8-bit wide bi-directional port. The corre-
sponding data direction register is TRISB. Setting a
TRISB bit (=1) will make the corresponding PORTB pin
an input, i.e., put the corresponding output driver in a
hi-impedance mode. Clearing a TRISB bit (=0) will
make the corresponding PORTB pin an output, i.e., put
the contents of the output latch on the selected pin.
Each of the PORTB pins, if configured as input, also
has an interrupt on change feature, which can be indi-
vidually selected from the IOCB register. The RBIE bit
in the INTCON register functions as a global enable bit
to turn on/off the interrupt on change feature. The
selected inputs are compared to the old value latched
on the last read of PORTB. The "mismatch" outputs are
OR’ed together to generate the RB Port Change Inter-
rupt with flag bit RBIF (INTCON<0>).
EXAMPLE 3-2: INITIALIZING PORTB
BCF
CLRF
STATUS, RP0 ;
PORTB ; Initialize PORTB by
; clearing output
; data latches
STATUS, RP0 ; Select Bank 1
This interrupt can wake the device from SLEEP. The
user, in the interrupt service routine, can clear the inter-
rupt in the following manner:
BSF
MOVLW 0xCF
; Value used to
; initialize data
; direction
; Set RB<3:0> as inputs
; RB<5:4> as outputs
; RB<7:6> as inputs
; Set RB<1:0> as analog
inputs
a) Any read or write of PORTB. This will end the
mismatch condition.
MOVWF TRISB
b) Clear flag bit RBIF.
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 03
MOVWF ANSEL
;
BCF
STATUS, RP0 ; Return to Bank 0
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.
Each of the PORTB pins has an internal pull-up, which
can be individually enabled from the WPUB register. A
single global enable bit can turn on/off the enabled pull-
ups. Clearing the RBPU bit, (OPTION_REG<7>),
REGISTER 3-2: WEAK PULL UP PORTB REGISTER (WPUB: 95h)
R/W-1
WPUB7
bit7
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
WPUB0
bit0
WPUB6
WPUB5
WPUB4
WPUB3
WPUB2
WPUB1
R = Readable bit
W = Writable bit
U = Unimplemented bit, read
as ‘0’
-n = Value at POR reset
bit 7-0: WPUB<7:0>: PORTB Weak Pull-Up Control
1= Weak pull up enabled.
0= Weak pull up disabled
Note 1: For the WPUB register setting to take effect, the RBPU bit in the OPTION_REG Register must be cleared.
2: The weak pull up device is automatically disabled if the pin is in output mode (TRIS = 0).
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 35
PIC16C717/770/771
REGISTER 3-3: INTERRUPT ON CHANGE PORTB REGISTER (IOCB: 96h)
R/W-1
IOCB7
R/W-1
IOCB6
R/W-1
IOCB5
R/W-1
IOCB4
R/W-0
IOCB3
R/W-0
IOCB2
R/W-0
IOCB1
R/W-0
IOCB0
R = Readable bit
W = Writable bit
bit7
bit0
U = Unimplemented bit, read
as ‘0’
-n = Value at POR reset
bit 7-0: IOCB<7:0>: Interrupt on Change PORTB Control
1= Interrupt on change enabled.
0= Interrupt on change disabled.
Note 1: The interrupt enable bits GIE and RBIE in the INTCON Register must be set for individual interrupts to be
recognized.
DS41120A-page 36
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
The RB0 pin is multiplexed with the A/D converter ana-
log input 4 and the external interrupt input (RB0/AN4/
INT). When the pin is used as analog input, the ANSEL
register must have the proper value to select the RB0
pin as analog mode.
The RB1 pin is multiplexed with the A/D converter ana-
log input 5 and the MSSP module slave select input
(RB1/AN5/SS). When the pin is used as analog input,
the ANSEL register must have the proper value to
select the RB1 pin as analog mode.
Note: Upon reset, the ANSEL register configures
the RB1 and RB0 pins as analog inputs.
Both RB1 and RB0 pins will read as ’0’.
FIGURE 3-7: BLOCK DIAGRAM OF RB0/AN4/INT, RB1/AN5/SS PIN
WPUB Reg
Data Bus
Q
D
WR
WPUB
CK
Q
VDD
RBPU
weak
pull-up
P
VDD
PORTB Reg
D
Q
VDD
P
WR
PORT
CK
Q
TRIS Reg
N
D
Q
WR
TRIS
VSS
CK
Q
RD
TRIS
VSS
Analog Select
D
Q
Q
WR
ANSEL
CK
TTL
IOCB Reg
D
Q
Schmitt
WR
IOCB
Set
RBIF
Trigger
Q
Q
CK
Q
D
Q1
From
RB<7:0> pins
EN
Q
D
D
Q3
EN
EN
RD
PORT
To INT input or MSSP module
To A/D Converter
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 37
PIC16C717/770/771
FIGURE 3-8: BLOCK DIAGRAM OF RB2/SCK/SCL, RB3/CCP1/P1A, RB4/SDI/SDA,
RB5/SDO/P1B
WPUB Reg
Data Bus
D
Q
WR
WPUB
CK
Q
VDD
Spec. Func En.
RBPU
VDD
weak
pull-up
P
SDA, SDO, SCK, CCPL, P1A, P1B
PORTB Reg
VDD
P
1
0
D
Q
WR
PORT
CK
Q
N
TRIS Reg
VSS
D
Q
WR
TRIS
VSS
CK
Q
RD
TRIS
TTL
IOCB Reg
Schmitt
Trigger
D
Q
WR
IOCB
Set
RBIF
Q
Q
D
CK
Q
Q1
From
RB<7:0> pins
EN
Q
D
D
Q3
EN
EN
RD
PORT
SCK, SCL, CC, SDI, SDA inputs
DS41120A-page 38
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 3-9: BLOCK DIAGRAM OF RB6/T1OSO/T1CKI/P1C
WPUB Reg
Data Bus
VDD
D
Q
RBPU
WR
WPUB
P
weak pull-up
CK
Q
VDD
P
D
Q
VDD
WR PORTB
WR TRISB
CK
Q
Data Latch
D
Q
Q
N
CK
TRIS Latch
VSS
TTL
RD TRISB
T1OSCEN
Input
Buffer
RD PORTB
IOCB Reg
D
Q
WR
IOCB
CK
Q
TMR1 Clock
Serial programming clock
From RB7
Schmitt
Trigger
TMR1 Oscillator
Q
D
Q1
EN
Set RBIF
Q
D
From
RB<7:0> pins
RD Port
Q3
EN
Note: The TMR1 oscillator enable (T1OSCEN = 1) overrides the RB6 I/O port and P1C functions.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 39
PIC16C717/770/771
FIGURE 3-10: BLOCK DIAGRAM OF THE RB7/T1OSI/P1D
VDD
RBPU
TMR1 Oscillator
weak pull-up
P
To RB6
WPUB Reg
Data Bus
D
Q
T1OSCEN
WR
WPUB
CK
Q
VDD
VDD
P
D
Q
Q
WR PORTB
WR TRISB
CK
Data Latch
D
Q
Q
N
CK
TRIS Latch
VSS
RD TRISB
T10SCEN
TTL
Input
Buffer
RD PORTB
IOCB Reg
D
Q
WR
IOCB
CK
Q
Serial programming input
Q
Q
D
Schmitt Trigger
Set RBIF
Q1
EN
D
From
RB<7:0> pins
RD Port
Q3
EN
Note: The TMR1 oscillator enable (T1OSCEN = 1) overrides the RB7 I/O port and P1D functions.
DS41120A-page 40
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 3-3:
PORTB FUNCTIONS
Input
Type
Output
Type
Name
Function
Description
(1)
RB0
AN4
INT
TTL
AN
ST
CMOS
Bi-directional I/O
RB0/AN4/INT
RB1/AN5/SS
A/D input
Interrupt input
Bi-directional I/O
A/D input
(1)
RB1
AN5
SS
TTL
AN
ST
CMOS
SSP slave select input
(1)
RB2
SCK
SCL
RB3
CCP1
P1A
TTL
ST
CMOS
CMOS
OD
Bi-directional input
RB2/SCK/SCL
RB3/CCP1/P1A
RB4/SDI/SDA
RB5/SDO/P1B
Serial clock I/O for SPI
2
ST
Serial clock I/O for I C
(1)
TTL
ST
CMOS
CMOS
CMOS
CMOS
Bi-directional input
Capture 1 input/Compare 1 output
PWM P1A output
(1)
RB4
SDI
TTL
ST
Bi-directional input
Serial data in for SPI
2
SDA
RB5
SDO
P1B
ST
OD
Serial data I/O for I C
(1)
ST
CMOS
CMOS
CMOS
CMOS
XTAL
Bi-directional I/O
Serial data out for SPI
PWM P1B output
(1)
RB6
T1OSO
T1CKI
P1C
RB7
T1OSI
P1D
TTL
ST
Bi-directional I/O
Crystal/Resonator
TMR1 clock input
PWM P1C output
RB6/T1OSO/T1CKI/P1C
CMOS
CMOS
(1)
TTL
Bi-directional I/O
RB7/T1OSI/P1D
XTAL
TMR1 crystal/resonator
PWM P1D output
CMOS
Note 1: Bit programmable pull-ups.
TABLE 3-4:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
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
xxxx xx00 uuuu uu00
1111 1111 1111 1111
1111 1111 1111 1111
1111 1111 1111 1111
1111 0000 1111 0000
1111 1111 1111 1111
06h, 106h PORTB
86h, 186h TRISB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
PORTB Data Direction Register
T0SE
PORTB Weak Pull-up Control
PORTB Interrupt on Change Control
ANS5 ANS4
81h, 181h OPTION_REG RBPU INTEDG T0CS
PSA
PS2
PS1
PS0
95h
96h
9Dh
WPUB
IOCB
ANSEL
ANS3
ANS2
ANS1
ANS0
Legend: x= unknown, u= unchanged. Shaded cells are not used by PORTB.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 41
PIC16C717/770/771
NOTES:
DS41120A-page 42
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
When interfacing the program memory block, the
PMDATH & PMDATL registers form a 2-byte word,
which holds the 14-bit data. The PMADRH & PMADRL
registers form a 2-byte word, which holds the 12-bit
address of the program memory location being
accessed. Mid-range devices have up to 8K words of
program EPROM with an address range from 0h to
3FFFh. When the device contains less memory than
the full address range of the PMADRH:PMARDL regis-
ters, the most significant bits of the PMADRH register
are ignored.
4.0
PROGRAM MEMORY READ
(PMR)
Program memory is readable during normal operation
(full VDD range). It is indirectly addressed through the
Special Function Registers:
• PMCON1
• PMDATH
• PMDATL
• PMADRH
• PMADRL
4.0.1
PMCON1 REGISTER
PMCON1 is the control register for program memory
accesses.
Control bit RD initiates a read operation. This bit cannot
be cleared, only set, in software. It is cleared in hard-
ware at completion of the read operation.
REGISTER 4-1: PROGRAM MEMORY READ CONTROL REGISTER 1 (PMCON1: 18Ch)
R-1
Reserved
bit7
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
U-0
—
R/S-0
RD
R = Readable bit
W = Writable bit
S = Settable bit
bit0
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7:
bit 6-1: Unimplemented: Read as '0'
bit 0: RD: Read Control bit
Reserved: Read as ‘1’
1= Initiates a Program memory read (read takes 2 cycles. RD is cleared in hardware.
0= Reserved
4.0.2
PMDATH AND PMDATL REGISTERS
The PMDATH:PMDATL registers are loaded with the
contents of program memory addressed by the
PMADRH and PMADRL registers upon completion of a
Program Memory Read command.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 43
PIC16C717/770/771
REGISTER 4-2: PROGRAM MEMORY DATA HIGH (PMDATH: 10Eh)
U-0
—
U-0
R-x
R-x
R-x
R-x
R-x
R-x
PMD8
bit0
—
PMD13 PMD12 PMD11 PMD10
PMD9
R = Readable bit
W = Writable bit
S = Settable bit
bit7
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-6: Unimplemented: Read as '0'
bit 5-0: PMD<13:8>: The value of the program memory word pointed to by PMADRH and PMADRL after a
program memory read command.
REGISTER 4-3: PROGRAM MEMORY DATA LOW (PMDATL: 10Ch)
R-x
PMD7
bit7
R-x
R-x
R-x
R-x
R-x
R-x
R-x
PMD0
bit0
PMD6
PMD5
PMD4
PMD3
PMD2
PMD1
R = Readable bit
W = Writable bit
S = Settable bit
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-0: PMD<7:0>: The value of the program memory word pointed to by PMADRH and PMADRL after a
program memory read command.
REGISTER 4-4: PROGRAM MEMORY ADDRESS HIGH (PMADRH: 10Fh)
U-0
—
U-0
—
U-0
—
U-0
—
R/W-x
R/W-x
R/W-x
PMA9
R/W-x
PMA8
bit0
PMA11 PMA10
R = Readable bit
W = Writable bit
S = Settable bit
bit7
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-4: Unimplemented: Read as '0'
bit 3-0: PMA<11:8>: PMR Address bits
REGISTER 4-5: PROGRAM MEMORY ADDRESS LOW (PMADRL: 10Dh)
R/W-x
PMA7
bit7
R/W-x
PMA6
R/W-x
PMA5
R/W-x
PMA4
R/W-x
PMA3
R/W-x
PMA2
R/W-x
PMA1
R/W-x
PMA0
bit0
R = Readable bit
W = Writable bit
S = Settable bit
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-0: PMA<7:0>: PMR Address bits
DS41120A-page 44
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
4.0.3
READING THE EPROM PROGRAM
MEMORY
causes the second instruction immediately following
the “BSF PMCON1,RD” instruction to be ignored. The data
is available, in the very next cycle, in the PMDATH and
PMDATL registers; therefore it can be read as 2 bytes
in the following instructions. PMDATH and PMDATL
registers will hold this value until another read or until it
is written to by the user.
To read a program memory location, the user must
write 2 bytes of the address to the PMADRH and
PMADRL registers, then set control bit RD
(PMCON1<0>). Once the read control bit is set, the
Program Memory Read (PMR) controller will use the
second instruction cycle after to read the data. This
EXAMPLE 4-1: OTP PROGRAM MEMORY READ
BSF
STATUS, RP1
;
BCF
STATUS, RP0
; Bank 2
MOVLW
MOVWF
MOVLW
MOVWF
BSF
MS_PROG_PM_ADDR ;
PMADRH
; MS Byte of Program Memory Address to read
LS_PROG_PM_ADDR ;
PMADRL
; LS Byte of Program Memory Address to read
STATUS, RP0
PMCON1, RD
; Bank 3
; Program Memory Read
BSF
NOP
NOP
; This instruction is executed
; This instruction must be a NOP
; PMDATH:PMDATL now has the data
next instruction
4.0.4
OPERATION DURING CODE PROTECT
When the device is code protected, the CPU can still
perform the program memory read function.
FIGURE 4-1: PROGRAM MEMORY READ CYCLE EXECUTION
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Program
Memory
ADDR
PMADRH,PMADRL
PC
PC+1
PC+3
PC+4
PC+5
BSF PMCON1,RD
Executed here
INSTR(PC-1)
Executed here
INSTR(PC+1)
Executed here
Forced NOP
Executed here
INSTR(PC+3)
Executed here
INSTR(PC+4)
Executed here
RD bit
PMDATH
PMDATL
register
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 45
PIC16C717/770/771
NOTES:
DS41120A-page 46
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Additional information on external clock requirements
is available in the PICmicro™ Mid-Range Reference
Manual, (DS33023).
5.0
TIMER0 MODULE
The Timer0 module timer/counter has the following fea-
tures:
5.2
Prescaler
• 8-bit timer/counter
• Readable and writable
An 8-bit counter is available as a prescaler for the
Timer0 module, or as a postscaler for the Watchdog
Timer, respectively (Figure 5-2). 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.
• Internal or external clock select
• Edge select for external clock
• 8-bit software programmable prescaler
• Interrupt on overflow from FFh to 00h
Figure 5-1 is a simplified block diagram of the Timer0
module.
Additional information on timer modules is available in
the PICmicro™ Mid-Range Reference Manual,
(DS33023).
The prescaler is not readable or writable.
The PSA and PS<2:0> bits (OPTION_REG<3:0>)
determine the prescaler assignment and prescale ratio.
5.1
Timer0 Operation
Timer0 can operate as a timer or as a counter.
Clearing bit PSA will assign the prescaler to the Timer0
module. When the prescaler is assigned to the Timer0
module, prescale values of 1:2, 1:4, ..., 1:256 are
selectable.
Timer mode is selected by clearing bit T0CS
(OPTION_REG<5>). In timer mode, the Timer0 mod-
ule will increment every instruction cycle (without pres-
caler). If the TMR0 register is written, the increment is
inhibited for the following two instruction cycles. The
user can work around this by writing an adjusted value
to the TMR0 register.
Setting bit PSA will assign the prescaler to the Watch-
dog Timer (WDT). When the prescaler is assigned to
the WDT, prescale values of 1:1, 1:2, ..., 1:128 are
selectable.
Counter mode is selected by setting bit T0CS
(OPTION_REG<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 Source Edge Select bit T0SE
(OPTION_REG<4>). Clearing bit T0SE selects the ris-
ing edge. Restrictions on the external clock input are
discussed in below.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g. CLRF 1, MOVWF 1,
BSF 1, x....etc.) will clear the prescaler. When
assigned to WDT, a CLRWDT instruction will clear the
prescaler along with the WDT.
Note: Writing to TMR0 when the prescaler is
assigned to Timer0 will clear the prescaler
count, but will not change the prescaler
assignment.
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.
FIGURE 5-1: 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 TCY delay)
T0SE
3
Set interrupt
flag bit T0IF
on overflow
PS2, PS1, PS0
PSA
T0CS
Note 1: T0CS, T0SE, PSA, PS<2:0> (OPTION_REG<5:0>).
2: The prescaler is shared with Watchdog Timer (refer to Figure 5-2 for detailed block diagram).
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 47
PIC16C717/770/771
5.2.1
SWITCHING PRESCALER ASSIGNMENT
5.3
Timer0 Interrupt
The prescaler assignment is fully under software con-
trol, i.e., it can be changed “on-the-fly” during program
execution.
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.
Note: To avoid an unintended device RESET, a
specific instruction sequence (shown in the
PICmicro™ Mid-Range Reference Man-
ual, DS33023) must be executed when
changing the prescaler assignment from
Timer0 to the WDT. This sequence must
be followed even if the WDT is disabled.
FIGURE 5-2: 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
PS<2:0>
PSA
1
0
WDT Enable Bit
M U X
PSA
WDT
Time-out
Note: T0CS, T0SE, PSA, PS<2:0> are (OPTION_REG<5:0>).
TABLE 5-1:
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 register
GIE PEIE
xxxx xxxx uuuu uuuu
RBIF 0000 000x 0000 000u
0Bh,8Bh,
10Bh,18Bh
INTCON
T0IE INTE
RBIE
PSA
T0IF
PS2
INTF
PS1
81h,181h
85h
OPTION_REG RBPU INTEDG T0CS T0SE
TRISA PORTA Data Direction Register
PS0
1111 1111 1111 1111
1111 1111 1111 1111
Legend: x= unknown, u= unchanged, -= unimplemented locations read as ’0’. Shaded cells are not used by Timer0.
DS41120A-page 48
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
6.1
Timer1 Operation
6.0
TIMER1 MODULE
The Timer1 module timer/counter has the following fea-
tures:
Timer1 can operate in one of these modes:
• As a timer
• 16-bit timer/counter
(Two 8-bit registers; TMR1H and TMR1L)
• As a synchronous counter
• As an asynchronous counter
• Readable and writable (Both registers)
• Internal or external clock select
The operating mode is determined by the clock select
bit, TMR1CS (T1CON<1>).
• Interrupt on overflow from FFFFh to 0000h
• Reset from ECCP module trigger
In timer mode, Timer1 increments every instruction
cycle. In counter mode, it increments on every rising
edge of the external clock input.
Timer1 has a control register, shown in Register 6-1.
Timer1 can be enabled/disabled by setting/clearing
control bit TMR1ON (T1CON<0>).
When the Timer1 oscillator is enabled (T1OSCEN is
set), the RB7/T1OSI/P1D and RB6/T1OSO/T1CKI/
P1C pins are no longer available as I/O ports or PWM
outputs. That is, the TRISB<7:6> value is ignored.
Figure 6-2 is a simplified block diagram of the Timer1
module.
Additional information on timer modules is available in
the PICmicro™ Mid-Range Reference Manual,
(DS33023).
Timer1 also has an internal “reset input”. This reset can
be generated by the ECCP module (Section 7.0).
REGISTER 6-1: TIMER1 CONTROL REGISTER (T1CON: 10h)
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R
W
U
= Readable bit
= Writable bit
= Unimplemented bit,
read as ‘0’
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
bit0
bit7
- n = Value at POR reset
bit 7-6: Unimplemented: Read as ’0’
bit 5-4: T1CKPS<1:0>: 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 RB6/T1OSO/T1CKI /P1C(on the rising edge)
0= Internal clock (FOSC/4)
TMR1ON: Timer1 On bit
1= Enables Timer1
0= Stops Timer1
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 49
PIC16C717/770/771
6.1.1
TIMER1 COUNTER OPERATION
In this mode, Timer1 is being incremented via an exter-
nal source. Increments occur on a rising edge. After
Timer1 is enabled in counter mode, the module must
first have a falling edge before the counter begins to
increment.
FIGURE 6-1: TIMER1 INCREMENTING EDGE
T1CKI
(Initially high)
First falling edge
of the T1ON enabled
T1CKI
(Initially low)
First falling edge
of the T1ON enabled
Note: Arrows indicate counter increments.
FIGURE 6-2: TIMER1 BLOCK DIAGRAM
Set flag bit
TMR1IF on
Overflow
Synchronized
clock input
0
TMR1
TMR1L
TMR1H
T1OSC
1
TMR1ON
on/off
T1SYNC
RB6/T1OSO/T1CKI/P1C
RB7/T1OSI/P1D
1
Synchronize
det
Prescaler
1, 2, 4, 8
T1OSCEN
Enable
Oscillator
FOSC/4
Internal
Clock
0
(1)
2
SLEEP input
T1CKPS<1:0>
TMR1CS
Note 1: When the T1OSCEN bit is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
DS41120A-page 50
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
6.2
Timer1 Oscillator
6.3
Timer1 Interrupt
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 6-1 shows the capacitor
selection for the Timer1 oscillator.
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/clear-
ing TMR1 interrupt enable bit TMR1IE (PIE1<0>).
6.4
Resetting Timer1 using a CCP Trigger
Output
The Timer1 oscillator is identical to the LP oscillator.
The user must provide a software time delay to ensure
proper oscillator start-up.
If the ECCP module is configured in compare mode to
generate a “special event trigger" (CCP1M<3:0> =
1011), this signal will reset Timer1 and start an A/D
conversion (if the A/D module is enabled).
TABLE 6-1:
CAPACITOR SELECTION FOR
THE TIMER1 OSCILLATOR
Osc Type
Freq
C1
C2
Note: The special event triggers from the CCP1
module will not set interrupt flag bit
TMR1IF (PIR1<0>).
LP
32 kHz
100 kHz
200 kHz
33 pF
15 pF
15 pF
33 pF
15 pF
15 pF
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.
These values are for design guidance only.
Note 1: Higher capacitance increases the stability of
oscillator but also increases the start-up time.
2: Since each resonator/crystal has its own charac-
teristics, the user should consult the resonator/
crystal manufacturer for appropriate values of
external components.
In the event that a write to Timer1 coincides with a spe-
cial event trigger from ECCP1, the write will take prece-
dence.
In this mode of operation, the CCPR1H:CCPR1L regis-
ters pair effectively becomes the period register for
Timer1.
TABLE 6-2:
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
-0-- 0000
-0-- 0000
xxxx xxxx
xxxx xxxx
--00 0000
-0-- 0000
-0-- 0000
uuuu uuuu
uuuu uuuu
--uu uuuu
0Ch
8Ch
0Eh
0Fh
10h
PIR1
—
—
ADIF
ADIE
—
—
—
—
SSPIF
SSPIE
CCP1IF
CCP1IE
TMR2IF
TMR2IE
TMR1IF
TMR1IE
PIE1
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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 51
PIC16C717/770/771
NOTES:
DS41120A-page 52
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
7.1
Timer2 Operation
7.0
TIMER2 MODULE
The Timer2 module timer has the following features:
Timer2 can be used as the PWM time-base for PWM
mode of the ECCP module.
• 8-bit timer (TMR2 register)
• 8-bit period register (PR2)
The TMR2 register is readable and writable, and is
cleared on any device reset.
• Readable and writable (Both registers)
• Software programmable prescaler (1:1, 1:4, 1:16)
• Software programmable postscaler (1:1 to 1:16)
• Interrupt on TMR2 match of PR2
The input clock (FOSC/4) has a prescale option of 1:1,
1:4 or 1:16, selected by control bits T2CKPS<1:0>
(T2CON<1:0>).
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>)).
• SSP module optional use of TMR2 output to gen-
erate clock shift
Timer2 has a control register, shown in Register 7-1.
Timer2 can be shut off by clearing control bit TMR2ON
(T2CON<2>) to minimize power consumption.
The prescaler and postscaler counters are cleared
when any of the following occurs:
Figure 7-1 is a simplified block diagram of the Timer2
module.
• a write to the TMR2 register
• a write to the T2CON register
Additional information on timer modules is available in
the PICmicro™ Mid-Range Reference Manual,
(DS33023).
• any device reset (Power-on Reset, MCLR Reset,
Watchdog Timer Reset, or Brown-out Reset)
TMR2 is not cleared when T2CON is written.
REGISTER 7-1:
TIMER2 CONTROL REGISTER (T2CON1: 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
W
U
= Readable bit
= Writable bit
= Unimplemented bit,
read as ‘0’
bit7
- n = Value at POR reset
bit 7:
Unimplemented: Read as ’0’
bit 6-3: TOUTPS<3:0>: 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: 2CKPS<1:0>: Timer2 Clock Prescale Select bits
00= Prescaler is 1
01= Prescaler is 4
1x= Prescaler is 16
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 53
PIC16C717/770/771
7.2
Timer2 Interrupt
FIGURE 7-1: TIMER2 BLOCK DIAGRAM
Sets flag
TMR2
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.
output (1)
bit TMR2IF
Reset
Prescaler
1:1, 1:4, 1:16
TMR2 reg
FOSC/4
Postscaler
1:1 to 1:16
2
Comparator
7.3
Output of TMR2
EQ
4
The output of TMR2 (before the postscaler) is fed to the
Synchronous Serial Port module which optionally uses
it to generate shift clock.
PR2 reg
Note 1: TMR2 register output can be software selected
by the SSP Module as a baud clock.
TABLE 7-1:
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
-0-- 0000 -0-- 0000
-0-- 0000 -0-- 0000
0000 0000 0000 0000
-000 0000 -000 0000
1111 1111 1111 1111
0Ch
8Ch
11h
12h
92h
PIR1
—
ADIF
ADIE
—
—
—
—
SSPIF
SSPIE
CCP1IF
CCP1IE
TMR2IF
TMR2IE
TMR1IF
TMR1IE
PIE1
—
TMR2
T2CON
PR2
Timer2 register
—
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0
Timer2 Period Register
Legend: x= unknown, u= unchanged, -= unimplemented read as ’0’. Shaded cells are not used by the Timer2 module.
DS41120A-page 54
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Capture/Compare/PWM Register1 (CCPR1) is com-
prised of two 8-bit registers: CCPR1L (low byte) and
CCPR1H (high byte). The CCP1CON and P1DEL reg-
isters control the operation of ECCP. All are readable
and writable.
8.0
ENHANCED CAPTURE/
COMPARE/PWM(ECCP)
MODULES
The ECCP (Enhanced 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.
Table 8-1 shows the timer resources of the ECCP mod-
ule modes.
REGISTER 8-1: CCP1 CONTROL REGISTER (CCP1CON: 17h)
R/W-0
R/W-0
R/W-0 R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
PWM1M1 PWM1M0 DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0
R = Readable bit
W= Writable bit
bit7
bit0
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-6: PWM1M<1:0>: PWM Output Configuration
IF CCP1M<3:2> = 00, 01, 10
xx- P1A assigned as Capture/Compare input. P1B, P1C, P1D assigned as Port pins.
IF CCP1M<3:2> = 11
00- Single output. P1A modulated. P1B, P1C, P1D assigned as Port pins.
01- Full-bridge output forward. P1D modulated. P1A active. P1B, P1C inactive.
10- Half-bridge output. P1A, P1B modulated with deadband control. P1C, P1D assigned as Port pins.
11- Full-bridge output reverse. P1B modulated. P1C active. P1A, P1D inactive.
bit 5-4: DC1B<1:0>: PWM Duty Cycle 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 CCPRnL.
bit 3-0: CCP1M<3:0>: ECCP1 Mode Select bits
0000= Capture/Compare/PWM off (resets ECCP module)
0001= Unused (reserved)
0010= Compare mode, toggle output on match (CCP1IF bit is set)
0011= Unused (reserved)
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 (CCP1IF bit is set)
1001= Compare mode, clear output on match (CCP1IF bit is set)
1010= Compare mode, generate software interrupt on match (CCP1IF bit is set, CCP1 pin is
unaffected)
1011= Compare mode, trigger special event (CCP1IF bit is set; ECCP resets TMR1, and starts an
A/D conversion, if the A/D module is enabled.)
1100= PWM mode. P1A, P1C active high. P1B, P1D active high.
1101= PWM mode. P1A, P1C active high. P1B, P1D active low.
1110= PWM mode. P1A, P1C active low. P1B, P1D active high.
1111= PWM mode. P1A, P1C active low. P1B, P1D active low.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 55
PIC16C717/770/771
TABLE 8-1:
ECCP MODE - TIMER
RESOURCE
EXAMPLE 8-1: CHANGING BETWEEN
CAPTURE PRESCALERS
CLRF
CCP1CON, F ; Turn ECCP module off
ECCP1 Mode
Timer Resource
MOVLW NEW_CAPT_PS ; Load WREG with the
; new prescaler mode
Capture
Compare
PWM
Timer1
Timer1
Timer2
; value and ECCP ON
; Load CCP1CON with
; this value
MOVWF CCP1CON
8.1
Capture Mode
FIGURE 8-1: 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 CCP1. An event is defined as:
Set flag bit CCP1IF
(PIR1<2>)
Prescaler
÷ 1, 4, 16
• every falling edge
• every rising edge
RB3/CCP1/
P1A Pin
CCPR1H
CCPR1L
TMR1L
Capture
Enable
• every 4th rising edge
• every 16th rising edge
and
edge detect
TMR1H
An event is selected by control bits CCP1M<3:0>
(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.
CCP1CON<3:0>
Q’s
8.2
Compare Mode
In Compare mode, the 16-bit CCPR1 register value is
constantly compared against the TMR1 register pair
value. When a match occurs, the CCP1 pin is:
8.1.1
CCP1 PIN CONFIGURATION
In Capture mode, the CCP1 pin should be configured
as an input by setting the TRISB<3> bit.
• driven High
• driven Low
Note: If the RB3/CCP1/P1A pin is configured as
an output, a write to the port can cause a
capture condition.
• toggle output (High to Low or Low to High)
• remains Unchanged
The action on the pin is based on the value of control
bits CCP1M<3:0>. At the same time, interrupt flag bit
CCP1IF is set.
8.1.2
TIMER1 MODE SELECTION
Timer1 must be running in timer mode or synchronized
counter mode. In asynchronous counter mode, the
capture operation may not work.
8.2.1
CCP1 PIN CONFIGURATION
The user must configure the CCP1 pin as an output by
clearing the appropriate TRISB bit.
8.1.3
SOFTWARE INTERRUPT
Note: Clearing the CCP1CON register will force
the CCP1 compare output latch to the
default low level. This is not the port data
latch.
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.
8.2.2
TIMER1 MODE SELECTION
8.1.4
ECCP PRESCALER
Timer1 must be running in Timer mode or Synchro-
nized Counter mode if the ECCP module is using the
compare feature. In Asynchronous Counter mode, the
compare operation may not work.
There are four prescaler settings, specified by bits
CCP1M<3:0>. Whenever the ECCP module is turned
off or the ECCP1 module is not in capture mode, the
prescaler counter is cleared. This means that any reset
will clear the prescaler counter.
8.2.3
SOFTWARE INTERRUPT MODE
When generate software interrupt is chosen, the CCP1
pin is not affected. Only an ECCP interrupt is generated
(if enabled).
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 8-1 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.
DS41120A-page 56
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
8.2.4
SPECIAL EVENT TRIGGER
FIGURE 8-2: COMPARE MODE
OPERATION BLOCK
DIAGRAM
In this mode, an internal hardware trigger is generated,
which may be used to initiate an action.
The special event trigger output of ECCP resets the
TMR1 register pair. This allows the CCPR1 register to
effectively be a 16-bit programmable period register for
Timer1.
Special event trigger will:
reset Timer1, but not set interrupt flag bit TMR1IF (PIR1<0>).
The special event trigger output of ECCP module will
also start an A/D conversion if the A/D module is
enabled.
Special Event Trigger
Set flag bit CCP1IF
(PIR1<2>)
Note: The special event trigger will not set the
CCPR1H CCPR1L
interrupt flag bit TMR1IF (PIR1<0>).
Q
S
R
Output
Logic
Comparator
match
RB3/CCP1/
P1A Pin
TRISB<3>
Output Enable
TMR1H TMR1L
CCP1CON<3:0>
Mode Select
TABLE 8-2:
REGISTERS ASSOCIATED WITH CAPTURE, COMPARE AND TIMER1
Value on
POR,
BOR
Value on
all other
resets
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
INTCON
PIR1
GIE
PEIE
ADIF
ADIE
T0IE
RCIF
RCIE
INTE
TXIF
TXIE
RBIE
SSPIF
SSPIE
T0IF
INTF
RBIF
0000 000x
0000 0000
0000 0000
1111 1111
xxxx xxxx
xxxx xxxx
--00 0000
xxxx xxxx
xxxx xxxx
0000 0000
0000 000u
0000 0000
0000 0000
1111 1111
uuuu uuuu
uuuu uuuu
--uu uuuu
uuuu uuuu
uuuu uuuu
0000 0000
(1)
PSPIF
PSPIE
CCP1IF
CCP1IE
TMR2IF
TMR2IE
TMR1IF
TMR1IE
(1)
PIE1
TRISB
PORTB Data Direction Register
TMR1L
TMR1H
T1CON
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 TMR1register
—
—
T1CKPS1 T1CKPS0
T1OSCEN
T1SYNC
TMR1CS TMR1ON
Capture/Compare/PWM register1 (LSB)
Capture/Compare/PWM register1 (MSB)
PWM1M1 PWM1M0
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
Legend: x = unknown, u = unchanged, -= unimplemented read as ’0’. Shaded cells are not used by Capture and Timer1.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 57
PIC16C717/770/771
8.3
PWM Mode
In Pulse Width Modulation (PWM) mode, the ECCP
module produces up to a 10-bit resolution PWM output.
Figure 8-3 shows the simplified PWM block diagram.
FIGURE 8-3:
SIMPLIFIED PWM BLOCK DIAGRAM
PWM1M1<1:0> CCP1M<3:0>
CCP1CON<5:4>
Duty cycle registers
4
2
CCPR1L
CCP1/P1A
P1B
RB3/CCP1/P1A
RB5/SDO/P1B
TRISB<3>
TRISB<5>
TRISB<6>
TRISB<7>
CCPR1H (Slave)
Comparator
OUTPUT
CONTROLLER
Q
R
S
RB6/T1OSO/T1CKI/
P1C
P1C
(Note 1)
TMR2
P1D
RB7/T1OSI/P1D
Comparator
PR2
Clear Timer,
CCP1 pin and
latch D.C.
P1DEL
Note: 8-bit timer TMR2 is concatenated with 2-bit internal Q clock or 2 bits of the prescaler to create 10-bit time-base.
8.3.1
PWM PERIOD
The PWM period is specified by writing to the PR2 reg-
ister. The PWM period can be calculated using the fol-
lowing formula:
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:
• TMR2 is cleared
• The CCP1 pin is set (exception: if PWM duty
cycle = 0%, the CCP1 pin will not be set)
• The PWM duty cycle is latched from CCPR1L into
CCPR1H
Note: The Timer2 postscaler (see Section 7.0) 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.
DS41120A-page 58
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
8.3.2
PWM DUTY CYCLE
FIGURE 8-4: SINGLE PWM OUTPUT
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:
Period
CCP1(2)
Duty Cycle
(1)
(1)
PWM duty cycle = (CCPR1L:CCP1CON<5:4>) •
TOSC • (TMR2 prescale value)
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.
Note 1: At this time, the TMR2 register is equal to the PR2 register.
2: Output signal is shown as asserted high.
FIGURE 8-5: EXAMPLE OF SINGLE
OUTPUT APPLICATION
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.
PIC16C717/770/771
Using PWM as
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.
a D/A Converter
R
CCP1
VOUT
Maximum PWM resolution (bits) for a given PWM fre-
quency:
C
FOSC
---------------
log
FPWM
-----------------------------
=
bits
Using PWM to
Drive a Power
Load
V+
log(2)
PIC16C717/770/771
L
O
A
D
Note: If the PWM duty cycle value is longer than
the PWM period, the CCP1 pin will not be
cleared.
CCP1
8.3.3
PWM OUTPUT CONFIGURATIONS
The PWM1M1 bits in the CCP1CON register allows
one of the following configurations:
In the Half-Bridge output mode, two pins are used as
outputs. The RB3/CCP1/P1A pin has the PWM output
signal, while the RB5/SDO/P1B pin has the comple-
mentary PWM output signal. This mode can be used
for half-bridge applications, as shown on Figure 8-7, or
for full-bridge applications, where four power switches
are being modulated with two PWM signal.
• Single output
• Half-Bridge output
• Full-Bridge output, Forward mode
• Full-Bridge output, Reverse mode
In the Single Output mode, the RB3/CCP1/P1A pin is
used as the PWM output. Since the CCP1 output is
multiplexed with the PORTB<3> data latch, the
TRISB<3> bit must be cleared to make the CCP1 pin
an output.
Since the P1A and P1B outputs are multiplexed with
the PORTB<3> and PORTB<5> data latches, the
TRISB<3> and TRISB<5> bits must be cleared to con-
figure P1A and P1B as outputs.
In Half-Bridge output mode, the programmable dead-
band delay can be used to prevent shoot-through cur-
rent in bridge power devices. See Section 8.3.5 for
more details of the deadband delay operations.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 59
PIC16C717/770/771
8.3.4
OUTPUT POLARITY CONFIGURATION
The PWM output polarities must be selected before the
PWM outputs are enabled. Charging the polarity con-
figuration while the PWM outputs are active is not rec-
ommended, since it may result in unpredictable
operation.
The CCP1M<1:0> bits in the CCP1CON register allow
user to choose the logic conventions (asserted high/
low) for each of the outputs. See Register 8-1 for fur-
ther details.
FIGURE 8-6: HALF-BRIDGE PWM OUTPUT
Period
Period
Duty Cycle
P1A(2)
P1B(2)
td
td
(1)
(1)
(1)
td = Deadband Delay
Note 1: At this time, the TMR2 register is equal to the PR2 register.
2: Output signals are shown as asserted high.
DS41120A-page 60
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 8-7: EXAMPLE OF HALF-BRIDGE OUTPUT MODE APPLICATIONS
V+
PIC16C717/770/771
FET
DRIVER
+
V
-
P1A
+
-
LOAD
FET
DRIVER
+
V
-
P1B
V-
V+
PIC16C717/770/771
FET
DRIVER
FET
DRIVER
P1A
+
-
LOAD
FET
DRIVER
FET
DRIVER
P1B
V-
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 61
PIC16C717/770/771
In Full-Bridge output mode, four pins are used as out-
puts; however, only two outputs are active at a time. In
the Forward mode, RB3/CCP1/P1A pin is continuously
active, and RB7/T1OSI/P1D pin is modulated. In the
Reverse mode, RB6/T1OSO/T1CKI/P1C pin is contin-
uously active, and RB5/SDO/P1B pin is modulated.
P1A, P1B, P1C and P1D outputs are multiplexed with
PORTB<3> and PORTB<5:7> data latches. TRISB<3>
and TRISB<5:7> bits must be cleared to make the P1A,
P1B, P1C, and P1D pins output.
FIGURE 8-8: FULL-BRIDGE PWM OUTPUT
FORWARD MODE
Period
1
(2)
P1A
0
Duty Cycle
1
0
(2)
(2)
P1B
1
0
P1C
1
0
(2)
P1D
(1)
(1)
REVERSE MODE
Period
Duty Cycle
1
0
(2)
(2)
(2)
P1A
P1B
1
0
1
0
P1C
(2) 1
P1D
0
(1)
(1)
Note 1: At this time, the TMR2 register is equal to the PR2 register.
2: Output signal is shown as asserted high.
DS41120A-page 62
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 8-9: EXAMPLE OF FULL-BRIDGE APPLICATION
V+
PIC16C717/770/771
FET
DRIVER
FET
DRIVER
P1D
+
-
LOAD
P1C
FET
DRIVER
FET
DRIVER
P1A
P1B
V-
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 63
PIC16C717/770/771
8.3.5
PROGRAMMABLE DEADBAND DELAY
avoid this potentially destructive shoot-through current
from flowing during switching, turning on the power
switch is normally delayed to allow the other switch to
completely turn off.
In half-bridge or full-bridge applications, where all
power switches are modulated at the PWM frequency
at all time, the power switches normally require longer
time to turn off than to turn on. If both the upper and
lower power switches are switched at the same time
(one turned on, and the other turned off), both switches
will be on for a short period of time, until one switch
completely turns off. During this time, a very high cur-
rent, called shoot-through current, will flow through
both power switches, shorting the bridge supply. To
In the Half-Bridge Output mode, a digitally program-
mable deadband delay is available to avoid shoot-
through current from destroying the bridge power
switches. The delay occurs at the signal transition from
the non-active state to the active state. See Figure 8-6
for illustration. The P1DEL register sets the amount of
delay.
REGISTER 8-2: PWM DELAY REGISTER (P1DEL: 97H)
R/W-0
bit7
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as
‘0’
- n = Value at POR reset
bit 7-0: P1DEL<7:0>: PWM Delay count for Half-Bridge output mode: Number of FOSC/4 (Tosc•4) cycles
between the P1A transition and the P1B transition.
8.3.6
DIRECTION CHANGE IN FULL-BRIDGE
OUTPUT MODE
modulated outputs, P1A and P1C signals, will transition
to the new direction TOSC, 4•TOSC or 16•TOSC (for
Timer2 presale T2CKRS<1:0> = 00, 01 and 1x respec-
tively) earlier, before the end of the period. During this
transition cycle, the modulated outputs, P1B and P1D,
will go to the inactive state. See Figure 8-10 for illustra-
tion.
In the Full-Bridge Output mode, the PWM1M1 bit in the
CCP1CON register allows user to control the Forward/
Reverse direction. When the application firmware
changes this direction control bit, the ECCP module will
assume the new direction on the next PWM cycle. The
current PWM cycle still continues, however, the non-
FIGURE 8-10: PWM DIRECTION CHANGE
(1)
PERIOD
PERIOD
SIGNAL
DC
P1A (Active High)
P1B (Active High)
P1C (Active High)
P1D (Active High)
(2)
Note 1: The Direction bit in the ECCP Control Register (CCP1CON.PWM1M1) is written anytime during the PWM cycle.
2: The P1A and P1C signals switch TOSC, 4*Tosc or 16*TOSC depending on the Timer2 prescaler value earlier when
changing direction. The modulated P1B and P1D signals are inactive at this time.
DS41120A-page 64
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Note that in the Full-Bridge output mode, the ECCP
module does not provide any deadband delay. In gen-
eral, since only one output is modulated at all time,
deadband delay is not required. However, there is a sit-
uation where a deadband delay might be required. This
situation occurs when all of the following conditions are
true:
example, since the turn off time of the power devices is
longer than the turn on time, a shoot-through current
flows through the power devices, QB and QD, for the
duration of t= toff-ton. The same phenomenon will occur
to power devices, QC and QB, for PWM direction
change from reverse to forward.
If changing PWM direction at high duty cycle is required
for the user’s application, one of the following require-
ments must be met:
1. The direction of the PWM output changes when
the duty cycle of the output is at or near 100%.
2. The turn off time of the power switch, including
the power device and driver circuit, is greater
than turn on time.
1. Avoid changing PWM output direction at or near
100% duty cycle.
2. Use switch drivers that compensate the slow
turn off of the power devices. The total turn off
time (toff) of the power device and the driver
must be less than the turn on time (ton).
Figure 8-11 shows an example, where the PWM direc-
tion changes from forward to reverse at a near 100%
duty cycle. At time t1, the output P1A and P1D become
inactive, while output P1C becomes active. In this
FIGURE 8-11: PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE
FORWARD PERIOD
REVERSE PERIOD
1
0
P1A
P1B
1
0
(PWM)
1
0
P1C
1
0
P1D
(PWM)
t
on
1
0
External Switch C
t
off
1
0
External Switch D
Potential
Shoot Through
Current
t = t - t
1
0
off on
t
1
Note 1: All signals are shown as active high.
2: ton is the turn on delay of power switch and driver.
3: toff is the turn off delay of power switch and driver.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 65
PIC16C717/770/771
8.3.7
SYSTEM IMPLEMENTATION
8.3.9
SET UP FOR PWM OPERATION
When the ECCP module is used in the PWM mode, the
application hardware must use the proper external pull-
up and/or pull-down resistors on the PWM output pins.
When the microcontroller powers up, all of the I/O pins
are in the high-impedance state. The external pull-up
and pull-down resistors must keep the power switch
devices in the off state until the microcontroller drives
the I/O pins with the proper signal levels, or activates
the PWM output(s).
The following steps should be taken when configuring
the ECCP module for PWM operation:
1. Configure the PWM module:
a) Disable the CCP1/P1A, P1B, P1C and/or
P1D outputs by setting the respective
TRISB bits.
b) Set the PWM period by loading the PR2
register.
c) Set the PWM duty cycle by loading the
CCPR1L register and CCP1CON<5:4>
bits.
8.3.8
START-UP CONSIDERATIONS
Prior to enabling the PWM outputs, the P1A, P1B, P1C
and P1D latches may not be in the proper states.
Enabling the TRISB bits for output at the same time
with the CCP module may cause damage to the power
switch devices. The CCP1 module must be enabled in
the proper output mode with the TRISB bits enabled as
inputs. Once the CCP1 completes a full PWM cycle, the
P1A, P1B, P1C and P1D output latches are properly
initialized. At this time, the TRISB bits can be enabled
for outputs to start driving the power switch devices.
The completion of a full PWM cycle is indicated by the
TMR2IF bit going from a ’0’ to a ’1’.
d) Configure the ECCP module for the desired
PWM operation by loading the CCP1CON
register. With the CCP1M<3:0> bits select
the active high/low levels for each PWM
output. With the PWM1M<1:0> bits select
one of the available output modes: Single,
Half-Bridge, Full-Bridge, Forward or Full-
Bridge Reverse.
e) For Half-Bridge output mode, set the dead-
band delay by loading the P1DEL register.
2. Configure and start TMR2:
a) Clear the TMR2 interrupt flag bit by clearing
the TMR2IF bit in the PIR1 register.
b) Set the TMR2 prescale value by loading the
T2CKPS<1:0> bits in the T2CON register.
c) Enable Timer2 by setting the TMR2ON bit
in the T2CON register.
3. Enable PWM outputs after a new cycle has
started:
a) Wait until TMR2 overflows (TMR2IF bit
becomes a ’1’). The new PWM cycle begins
here.
b) Enable the CCP1/P1A, P1B, P1C and/or
P1D pin outputs by clearing the respective
TRISB bits.
TABLE 8-3:
REGISTERS ASSOCIATED WITH PWM
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,
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000u
18Bh
0Ch
8Ch
86h, 186h
11h
PIR1
—
—
ADIF
ADIE
—
—
—
—
SSPIF
SSPIE
CCP1IF
CCP1IE
TMR2IF
TMR2IE
TMR1IF
TMR1IE
-0-- 0000
-0-- 0000
1111 1111
0000 0000
1111 1111
-000 0000
xxxx xxxx
0000 0000
0000 0000
-0-- 0000
-0-- 0000
1111 1111
0000 0000
1111 1111
-000 0000
uuuu uuuu
0000 0000
0000 0000
PIE1
TRISB
TMR2
PORTB Data Direction Register
Timer2 register
92h
PR2
Timer2 period register
12h
T2CON
CCPR1L
CCP1CON
P1DEL
—
TOUTPS3
Capture/Compare/PWM register1 (LSB)
PWM1M1 PWM1M0 DC1B1
PWM1 Delay value
TOUTPS2
TOUTPS1
DC1B0
TOUTPS0
CCP1M3
TMR2ON
CCP1M2
T2CKPS1
CCP1M1
T2CKPS0
CCP1M0
15h
17h
97h
Legend: Legend: x = unknown, u = unchanged, -= unimplemented read as ’0’. Shaded cells are not used by Capture and Timer1.
DS41120A-page 66
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.0
MASTER SYNCHRONOUS
SERIAL PORT (MSSP)
MODULE
The Master Synchronous Serial Port (MSSP) module is
a serial interface useful for communicating with other
peripheral or microcontroller devices. These peripheral
devices may be serial EEPROMs, shift registers, dis-
play drivers, etc. The MSSP module can operate in one
of two modes:
• Serial Peripheral Interface (SPI™)
• Inter-Integrated Circuit (I2C™)
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 67
PIC16C717/770/771
REGISTER 9-1: SYNC SERIAL PORT STATUS REGISTER (SSPSTAT: 94h)
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:
SMP: Sample bit
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
In I2C master or slave mode:
1= Slew rate control disabled for standard speed mode (100 kHz and 1 MHz)
0= Slew rate control enabled for high speed mode (400 kHz)
bit 6:
CKE: SPI Clock Edge Select (Figure 9-3, Figure 9-5, and Figure 9-6)
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
bit 5:
bit 4:
D/A: Data/Address bit (I2C mode only)
1= Indicates that the last byte received or transmitted was data
0= Indicates that the last byte received or transmitted was address
P: Stop bit
(I2C mode only. This bit is cleared when the MSSP 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
bit 3:
bit 2:
S: Start bit
(I2C mode only. This bit is cleared when the MSSP 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
R/W: Read/Write bit information (I2C 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 not ACK bit.
In I2C slave mode:
1= Read
0= Write
In I2C master mode:
1= Transmit is in progress
0= Transmit is not in progress.
Or’ing this bit with SEN, RSEN, PEN, RCEN, or AKEN will indicate if the MSSP is in IDLE mode
bit 1:
bit 0:
UA: Update Address (10-bit I2C 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
Receive (SPI and I2C modes)
1= Receive complete, SSPBUF is full
0= Receive not complete, SSPBUF is empty
Transmit (I2C mode only)
1= Data Transmit in progress (does not include the ACK and stop bits), SSPBUF is full
0= Data Transmit complete (does not include the ACK and stop bits), SSPBUF is empty
DS41120A-page 68
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
REGISTER 9-2: SYNC SERIAL PORT CONTROL REGISTER (SSPCON: 14h)
R/W-0
WCOL
R/W-0
R/W-0
R/W-0
CKP
R/W-0
R/W-0
R/W-0
R/W-0
SSPOV
SSPEN
SSPM3
SSPM2
SSPM1
SSPM0
R = Readable bit
W = Writable bit
- n = Value at POR reset
bit7
bit0
bit 7:
WCOL: Write Collision Detect bit
Master Mode:
1= A write to the SSPBUF register was attempted while the I2C conditions were not valid for a
transmission to be started
0= No collision
Slave Mode:
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. 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. (Must be
cleared in software).
0= No overflow
In I2C 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. (Must be cleared in software).
0= No overflow
bit 5:
SSPEN: Synchronous Serial Port Enable bit
In both modes, when enabled, these pins must be properly configured as input or output.
In SPI mode
1= Enables serial port and configures SCK, SDO, SDI, and SS as the source of the serial port pins
0= Disables serial port and configures these pins as I/O port pins
In I2C mode
1= Enables the serial port and configures the SDA and SCL pins as the source of the serial port pins
0= Disables serial port and configures these pins as I/O port pins
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
In I2C slave mode
SCK release control
1= Enable clock
0= Holds clock low (clock stretch) (Used to ensure data setup time)
In I2C master mode
Unused in this mode
bit 3-0: SSPM<3:0>: 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
0110= I2C slave mode, 7-bit address
0111= I2C slave mode, 10-bit address
1000= I2C master mode, clock = FOSC / (4 • (SSPADD+1) )
1xx1= Reserved
1x1x= Reserved
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 69
PIC16C717/770/771
REGISTER 9-3: SYNC SERIAL PORT CONTROL REGISTER2 (SSPCON2: 91h)
R/W-0
GCEN
R/W-0
R/W-0
R/W-0
R/W-0
RCEN
R/W-0
PEN
R/W-0
RSEN
R/W-0
SEN
ACKSTAT
ACKDT
ACKEN
R = Readable bit
W = Writable bit
bit7
bit0
U = Unimplemented bit, Read
as ‘0’
- n = Value at POR reset
bit 7:
bit 6:
GCEN: General Call Enable bit (In I2C slave mode only)
1= Enable interrupt when a general call address (0000h) is received in the SSPSR.
0= General call address disabled.
ACKSTAT: Acknowledge Status bit (In I2C master mode only)
In master transmit mode:
1= Acknowledge was not received from slave
0= Acknowledge was received from slave
bit 5:
bit 4:
ACKDT: Acknowledge Data bit (In I2C master mode only)
In master receive mode:
Value that will be transmitted when the user initiates an Acknowledge sequence at the end of a receive.
1= Not Acknowledge
0= Acknowledge
ACKEN: Acknowledge Sequence Enable bit (In I2C master mode only).
In master receive mode:
1= Initiate Acknowledge sequence on SDA and SCL pins, and transmit ACKDT data bit. Automatically
cleared by hardware.
0= Acknowledge sequence idle
bit 3:
bit 2:
RCEN: Receive Enable bit (In I2C master mode only).
1= Enables Receive mode for I2C
0= Receive idle
PEN: Stop Condition Enable bit (In I2C master mode only).
SCK release control
1= Initiate Stop condition on SDA and SCL pins. Automatically cleared by hardware.
0= Stop condition idle
bit 1:
bit 0:
RSEN: Repeated Start Condition Enabled bit (In I2C master mode only)
1= Initiate Repeated Start condition on SDA and SCL pins. Automatically cleared by hardware.
0= Repeated Start condition idle.
SEN: Start Condition Enabled bit (In I2C master mode only)
1= Initiate Start condition on SDA and SCL pins. Automatically cleared by hardware.
0= Start condition idle.
2
Note:
For bits ACKEN, RCEN, PEN, RSEN, SEN: If the I C module is not in the idle mode, this bit may not be set (no
spooling) and the SSPBUF may not be written (or writes to the SSPBUF are disabled).
DS41120A-page 70
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.1
SPI Mode
FIGURE 9-1: MSSP BLOCK DIAGRAM
(SPI MODE)
The SPI mode allows 8 bits of data to be synchronously
transmitted and received simultaneously. All four
modes of SPI are supported. To accomplish communi-
cation, typically three pins are used:
Internal
Data Bus
Read
Write
• Serial Data Out (SDO)
• Serial Data In (SDI)
• Serial Clock (SCK)
SSPBUF reg
SSPSR reg
Additionally, a fourth pin may be used when in a slave
mode of operation:
Shift
Clock
SDI
• Slave Select (SS)
bit0
9.1.1
OPERATION
SDO
When initializing the SPI, several options need to be
specified. This is done by programming the appropriate
control bits (SSPCON<5:0> and SSPSTAT<7:6>).
These control bits allow the following to be specified:
Control
Enable
SS
SS
Edge
Select
• Master Mode (SCK is the clock output)
• Slave Mode (SCK is the clock input)
• Clock Polarity (Idle state of SCK)
• Data input sample phase
2
Clock Select
(middle or end of data output time)
• Clock edge
(output data on rising/falling edge of SCK)
• Clock Rate (Master mode only)
• Slave Select Mode (Slave mode only)
SSPM<3:0>
SMP:CKE
2
4
TMR2 Output
2
Edge
Select
Tosc
Prescaler
4, 16, 64
Figure 9-1 shows the block diagram of the MSSP mod-
ule when in SPI mode.
SCK
Data to TX/RX in SSPSR
Data direction bit
The MSSP 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 the 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 SSP-
BUF register completed successfully.
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 the SSP-
BUF has been loaded with the received data (transmis-
sion 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 MSSP Interrupt is used to
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 71
PIC16C717/770/771
determine when the transmission/reception has com-
pleted. The SSPBUF must be read and/or written. If the
interrupt method is not going to be used, then software
polling can be done to ensure that a write collision does
not occur. Example 9-1 shows the loading of the
SSPBUF (SSPSR) for data transmission.
SDI, SDO, SCK and SS pins as serial port pins. For the
pins to behave as the serial port function, some must
have their data direction bits (in the TRIS register)
appropriately programmed. That is:
• SDI is automatically controlled by the SPI module
• SDO must have TRISB<5> cleared
• SCK (Master mode) must have TRISB<2> cleared
• SCK (Slave mode) must have TRISB<2> set
EXAMPLE 9-1: LOADING THE SSPBUF
(SSPSR) REGISTER
• SS must have TRISB<1> set, and ANSEL<5>
cleared
BSF
STATUS, RP0
;Specify Bank 1
;Has data been
;received
LOOP BTFSS SSPSTAT, BF
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.
;(transmit
;complete)?
GOTO LOOP
;No
BCF
STATUS, RP0
;Specify Bank 0
;W reg = contents
;of SSPBUF
9.1.3
TYPICAL CONNECTION
MOVF SSPBUF, W
Figure 9-2 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 software. This leads to three scenarios for
data transmission:
MOVWF RXDATA
MOVF TXDATA, W
;Save in user RAM
;W reg = contents
; of TXDATA
MOVWF SSPBUF
;New data to xmit
The SSPSR is not directly readable or writable, and can
only be accessed by addressing the SSPBUF register.
Additionally, the MSSP status register (SSPSTAT) indi-
cates the various status conditions.
9.1.2
ENABLING SPI I/O
• Master sends data — Slave sends dummy data
• Master sends data — Slave sends data
To enable the serial port, MSSP Enable bit, SSPEN
(SSPCON<5>) must be set. To reset or reconfigure SPI
mode, clear bit SSPEN, re-initialize the SSPCON reg-
isters, and then set bit SSPEN. This configures the
• Master sends dummy data — Slave sends data
FIGURE 9-2: SPI MASTER/SLAVE CONNECTION
SPI Master SSPM<3:0> = 00xxb
SDO
SPI Slave SSPM<3:0> = 010xb
SDI
Serial Input Buffer
(SSPBUF)
Serial Input Buffer
(SSPBUF)
SDI
SDO
Shift Register
Shift Register
(SSPSR)
(SSPSR)
LSb
MSb
MSb
LSb
Serial Clock
SCK
SCK
PROCESSOR 1
PROCESSOR 2
DS41120A-page 72
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.1.4
MASTER MODE
Figure 9-3, Figure 9-5 and Figure 9-6, where the MSb
is transmitted first. In master mode, the SPI clock rate
(bit rate) is user programmable to be one of the follow-
ing:
The master can initiate the data transfer at any time
because it controls the SCK. The master determines
when the slave (Processor 2, Figure 9-2) is to broad-
cast data by the software protocol.
• FOSC/4 (or TCY)
• FOSC/16 (or 4 • TCY)
• FOSC/64 (or 16 • TCY)
• Timer2 output/2
In master mode, the data is transmitted/received as
soon as the SSPBUF register is written to. If the SPI
module is only going to receive, the SDO 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”.
This allows a maximum bit clock frequency (at 20 MHz)
of 8.25 MHz.
Figure 9-3 shows the waveforms for Master mode.
When CKE = 1, the SDO data is valid before there is a
clock edge on SCK. The change of the input sample is
shown based on the state of the SMP bit. The time
when the SSPBUF is loaded with the received data is
shown.
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 9-3: SPI MODE WAVEFORM (MASTER MODE)
Write to
SSPBUF
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
4 clock
modes
SCK
(CKP = 0
CKE = 1)
SCK
(CKP = 1
CKE = 1)
bit6
bit6
bit2
bit2
bit5
bit5
bit4
bit4
bit1
bit1
bit0
bit0
SDO
(CKE = 0)
bit7
bit7
bit3
bit3
SDO
(CKE = 1)
SDI
(SMP = 0)
bit0
bit7
Input
Sample
(SMP = 0)
SDI
(SMP = 1)
bit0
bit7
Input
Sample
(SMP = 1)
SSPIF
Next Q4 cycle
after Q2↓
SSPSR to
SSPBUF
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 73
PIC16C717/770/771
9.1.5
SLAVE MODE
SDO pin is no longer driven, even if in the middle of
a transmitted byte, and becomes a floating output.
External pull-up/ pull-down resistors may be desirable,
depending on the application.
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.
Note 1: When the SPI module is in Slave Mode
with SS pin control enabled, (SSP-
CON<3:0> = 0100) the SPI module will
reset if the SS pin is set to VDD.
While in slave mode, the external clock is supplied by
the external clock source on the SCK pin. This external
clock must meet the minimum high and low times as
specified in the electrical specifications.
2: If the SPI is used in Slave Mode with
CKE = ’1’, then SS pin control must be
enabled.
While in sleep mode, the slave can transmit/receive
data. When a byte is received, the device will wake-up
from sleep.
When the SPI module resets, the bit counter is forced
to 0. This can be done by either forcing the SS pin to a
high level or clearing the SSPEN bit.
9.1.6
SLAVE SELECT SYNCHRONIZATION
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.
The SS pin allows a synchronous slave mode. The
SPI must be in slave mode with SS pin control
enabled (SSPCON<3:0> = 0100). The pin must not
be driven low for the SS pin to function as an input.
TRISB<1> must be set. When the SS pin is low,
transmission and reception are enabled and the
SDO pin is driven. When the SS pin goes high, the
FIGURE 9-4: SLAVE SYNCHRONIZATION WAVEFORM
SS
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
Write to
SSPBUF
bit6
bit7
bit7
bit0
bit0
SDO
bit7
SDI
(SMP = 0)
bit7
Input
Sample
(SMP = 0)
SSPIF
Interrupt
Flag
Next Q4 cycle
after Q2Ø
SSPSR to
SSPBUF
DS41120A-page 74
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 9-5: SPI SLAVE MODE WAVEFORM (CKE = 0)
SS
optional
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
Write to
SSPBUF
bit6
bit2
bit5
bit4
bit1
bit0
SDO
bit7
bit3
SDI
(SMP = 0)
bit0
bit7
Input
Sample
(SMP = 0)
SSPIF
Interrupt
Flag
Next Q4 cycle
after Q2Ø
SSPSR to
SSPBUF
FIGURE 9-6: SPI SLAVE MODE WAVEFORM (CKE = 1)
SS
not optional
SCK
(CKP = 0
CKE = 1)
SCK
(CKP = 1
CKE = 1)
Write to
SSPBUF
bit6
bit2
bit5
bit4
bit1
bit0
bit0
SDO
bit7
bit7
bit3
SDI
(SMP = 0)
Input
Sample
(SMP = 0)
SSPIF
Interrupt
Flag
Next Q4 cycle
after Q2Ø
SSPSR to
SSPBUF
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 75
PIC16C717/770/771
9.1.7
SLEEP OPERATION
9.1.8
EFFECTS OF A RESET
In master mode, all module clocks are halted and the
transmission/reception will remain in that state until the
device wakes from sleep. After the device returns to
normal mode, the module will continue to transmit/
receive data.
A reset disables the MSSP module and terminates the
current transfer.
In slave mode, the SPI transmit/receive shift register
operates asynchronously to the device. This allows the
device to be placed in sleep mode and data to be
shifted into the SPI transmit/receive shift register.
When all 8 bits have been received, the MSSP interrupt
flag bit will be set and if enabled will wake the device
from sleep.
TABLE 9-1:
REGISTERS ASSOCIATED WITH SPI OPERATION
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR, BOR MCLR, WDT
0Bh, 8Bh,
10Bh,18Bh
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
0Ch
8Ch
13h
14h
94h
PIR1
—
—
ADIF
ADIE
—
—
—
—
SSPIF
SSPIE
CCP1IF
CCP1IE
TMR2IF
TMR2IE
TMR1IF -0-- 0000 -0-- 0000
TMR1IE -0-- 0000 -0-- 0000
xxxx xxxx uuuu uuuu
PIE1
SSPBUF
SSPCON
SSPSTAT
Synchronous Serial Port Receive Buffer/Transmit Register
WCOL
SMP
SSPOV
CKE
SSPEN
D/A
CKP
P
SSPM3
S
SSPM2
R/W
SSPM1
UA
SSPM0 0000 0000 0000 0000
BF
0000 0000 0000 0000
Legend: x= unknown, u= unchanged, -= unimplemented read as ’0’. Shaded cells are not used by the MSSP in SPI mode.
DS41120A-page 76
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2
MSSP I2C Operation
FIGURE 9-8: I2C MASTER MODE BLOCK
DIAGRAM
The MSSP module in I2C mode fully implements all
master and slave functions (including general call sup-
port) and provides interrupts on start and stop bits in
hardware to determine a free bus (multi-master func-
tion). The MSSP module implements the standard
mode specifications, as well as 7-bit and 10-bit
addressing.
Internal
Data Bus
Read
Write
SSPADD<6:0>
7
Baud Rate Generator
Refer to Application Note AN578, "Use of the SSP
Module in the I 2C Multi-Master Environment."
SSPBUF reg
SSPSR reg
SCL
A "glitch" filter is on the SCL and SDA pins when the pin
is an input. This filter operates in both the 100 kHz and
400 kHz modes. In the 100 kHz mode, when these pins
are an output, there is a slew rate control of the pin that
is independent of device frequency.
Shift
Clock
SDA
MSb
LSb
Addr Match
FIGURE 9-7: I2C SLAVE MODE BLOCK
DIAGRAM
Match detect
SSPADD reg
Internal
Data Bus
Set/Clear S bit
and
Read
Write
Start and Stop bit
detect / generate
Clear/Set P bit
(SSPSTAT reg)
SSPBUF reg
SSPSR reg
SCL
SDA
and Set SSPIF
Shift
Clock
Two pins are used for data transfer. These are the SCL
pin, which is the clock, and the SDA pin, which is the
data. The MSSP module functions are enabled by set-
ting SSP Enable bit SSPEN (SSPCON<5>).
MSb
LSb
The MSSP module has six registers for I2C operation.
They are the:
Addr Match
Match detect
SSPADD reg
• SSP Control Register (SSPCON)
• SSP Control Register2 (SSPCON2)
• SSP Status Register (SSPSTAT)
• Serial Receive/Transmit Buffer (SSPBUF)
• SSP Shift Register (SSPSR) - Not directly acces-
sible
Set, Reset
S, P bits
(SSPSTAT reg)
Start and
Stop bit detect
• SSP Address Register (SSPADD)
The SSPCON register allows control of the I2C opera-
tion. Four mode selection bits (SSPCON<3:0>) allow
one of the following I2C modes to be selected:
• I2C Slave mode (7-bit address)
• I2C Slave mode (10-bit address)
• I2C Master mode, clock = OSC/4 (SSPADD +1)
Before selecting any I2C mode, the SCL and SDA pins
must be programmed to inputs by setting the appropri-
ate TRIS bits. Selecting an I2C mode, by setting the
SSPEN bit, enables the SCL and SDA pins to be used
as the clock and data lines in I2C mode.
The SSPSTAT register gives the status of the data
transfer. This information includes detection of a
START (S) or STOP (P) bit, specifies if the received
byte was data or address if the next byte is the comple-
tion of 10-bit address, and if this will be a read or write
data transfer.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 77
PIC16C717/770/771
SSPBUF is the register to which the 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.
9.2.1.1
ADDRESSING
Once the MSSP module has been enabled, it waits for
a START condition to occur. Following the START con-
dition, 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
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:
a) The SSPSR register value is loaded into the
SSPBUF register on the falling edge of the 8th
SCL pulse.
The SSPADD register holds the slave address. In 10-bit
mode, the user 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).
b) The buffer full bit, BF is set on the falling edge of
the 8th SCL pulse.
c) An ACK pulse is generated.
d) SSP interrupt flag bit, SSPIF (PIR1<3>) is set
(interrupt is generated if enabled) - on the falling
edge of the 9th SCL pulse.
9.2.1
SLAVE MODE
In slave mode, the SCL and SDA pins must be config-
ured as inputs. The MSSP module will override the
input state with the output data when required (slave-
transmitter).
In 10-bit address mode, two address bytes need to be
received by the slave. The five Most Significant 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 second 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 a 10-bit
address is as follows, with steps 7- 9 for slave-transmit-
ter:
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.
There are certain conditions that will cause the MSSP
module not to give this ACK pulse. These are if either
(or both):
1. Receive first (high) byte of Address (bits SSPIF,
BF, and bit UA (SSPSTAT<1>) are set).
a) The buffer full bit BF (SSPSTAT<0>) was set
before the transfer was received.
2. Update the SSPADD register with second (low)
byte of Address (clears bit UA and releases the
SCL line).
b) The overflow bit SSPOV (SSPCON<6>) was set
before the transfer was received.
3. Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
If the BF bit is set, the SSPSR register value is not
loaded into the SSPBUF, but bit SSPIF and SSPOV are
set. Table 9-2 shows what happens when a data trans-
fer byte is received, given the status of bits BF and
SSPOV. The shaded cells show the condition where
user software did not properly clear the overflow condi-
tion. Flag bit BF is cleared by reading the SSPBUF reg-
ister while bit SSPOV is cleared through software.
4. Receive second (low) byte of Address (bits
SSPIF, BF, and UA are set).
5. Update the SSPADD register with the first (high)
byte of Address. This will clear bit UA and
release the SCL line.
6. Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
The SCL clock input must have a minimum high and
low time for proper operation. The high and low times
of the I2C specification as well as the requirement of the
MSSP module is shown in timing parameter #100 and
parameter #101 of the Electrical Specifications.
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.
Note: Following the Repeated Start condition
(step 7) in 10-bit mode, the user only
needs to match the first 7-bit address. The
user does not update the SSPADD for the
second half of the address.
DS41120A-page 78
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.1.2
SLAVE RECEPTION
A MSSP 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 received byte.
When the R/W bit of the address byte is clear and an
address match occurs, the R/W bit of the SSPSTAT
register is cleared. The received address is loaded into
the SSPBUF register.
Note: The SSPBUF will be loaded if the SSPOV
bit is set and the BF flag is cleared. If a
read of the SSPBUF was performed, but
the user did not clear the state of the
SSPOV bit before the next receive
occurred, the ACK is not sent and the SSP-
BUF is updated.
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>) or bit
SSPOV (SSPCON<6>) and is set.
TABLE 9-2:
DATA TRANSFER RECEIVED BYTE ACTIONS
Status Bits as Data
Transfer is Received
Set bit SSPIF
Generate ACK
Pulse
(SSP Interrupt occurs
if enabled)
BF
SSPOV
SSPSR → SSPBUF
0
1
1
0
0
0
1
1
Yes
No
Yes
No
No
No
Yes
Yes
Yes
Yes
No
Yes
Note 1: Shaded cells show the conditions where the user software did not properly clear the overflow condition.
9.2.1.3
SLAVE TRANSMISSION
A MSSP interrupt is generated for each data transfer
byte. The SSPIF flag bit must be cleared in software,
and the SSPSTAT register is used to determine the sta-
tus of the byte transfer. The SSPIF flag bit 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 the SCL pin is held low.
The transmit data must be loaded into the SSPBUF
register, which also loads the SSPSR register. Then the
SCL pin should be enabled by setting bit CKP (SSP-
CON<4>). The master must monitor the SCL pin prior
to asserting another clock pulse. The slave devices
may be holding off the master by stretching 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 9-10).
As a slave-transmitter, the ACK pulse from the master-
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 not ACK is latched
by the slave, the slave logic is reset 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 register. Then the SCL pin should be enabled
by setting the CKP bit.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 79
PIC16C717/770/771
FIGURE 9-9: I2C WAVEFORMS FOR RECEPTION (7-BIT ADDRESS)
R/W=0
ACK
Not
Receiving Address
A7 A6 A5 A4
Receiving Data
Receiving Data
ACK
ACK
SDA
A3 A2 A1
D5
D2
6
D0
8
D5
D2
D0
8
D7 D6
D4 D3
D7 D6
D4 D3
D1
7
D1
7
3
9
7
1
2
4
9
5
4
3
6
9
5
1
2
3
6
1
2
4
8
5
P
SCL
S
SSPIF
Bus Master
terminates
transfer
BF (SSPSTAT<0>)
Cleared in software
SSPBUF register is read
SSPOV (SSPCON<6>)
Bit SSPOV is set because the SSPBUF register is still full.
ACK is not sent.
FIGURE 9-10: I2C WAVEFORMS FOR TRANSMISSION (7-BIT ADDRESS)
R/W = 0
Transmitting Data Not ACK
D7 D6 D5 D4 D3 D2 D1 D0
R/W = 1
Receiving Address
ACK
SDA
SCL
A7 A6 A5 A4 A3 A2 A1
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
S
P
SCL held low
while CPU
responds to SSPIF
Data in
sampled
SSPIF
BF (SSPSTAT<0>)
CKP (SSPCON<4>)
cleared in software
SSPBUF is written in software
From SSP interrupt
service routine
Set bit after writing to SSPBUF
(the SSPBUF must be written-to
before the CKP bit can be set)
DS41120A-page 80
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
2
FIGURE 9-11: I C SLAVE-TRANSMITTER (10-BIT ADDRESS)
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 81
PIC16C717/770/771
2
FIGURE 9-12: I C SLAVE-RECEIVER (10-BIT ADDRESS)
DS41120A-page 82
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.2
GENERAL CALL ADDRESS SUPPORT
If the general call address matches, the SSPSR is
transferred to the SSPBUF, the BF flag is set (eighth
bit), and on the falling edge of the ninth bit (ACK bit), the
SSPIF flag is set.
The addressing procedure for the I2C bus is such that
the first byte after the START condition usually deter-
mines which device will be the slave addressed by the
master. The exception is the general call address,
which can address all devices. When this address is
used, all devices should, in theory, respond with an
acknowledge.
When the interrupt is serviced, the source for the inter-
rupt can be checked by reading the contents of the
SSPBUF to determine if the address was device spe-
cific or a general call address.
In 10-bit mode, the SSPADD is required to be updated
for the second half of the address to match, and the UA
bit is set (SSPSTAT<1>). If the general call address is
sampled when GCEN is set while the slave is config-
ured in 10-bit address mode, then the second half of
the address is not necessary, the UA bit will not be set,
and the slave will begin receiving data after the
acknowledge (Figure 9-13).
The general call address is one of eight addresses
reserved for specific purposes by the I2C protocol. It
consists of all 0’s with R/W = 0
The general call address is recognized when the Gen-
eral Call Enable bit (GCEN) is enabled (SSPCON2<7>
is set). Following a start-bit detect, 8 bits are shifted
into SSPSR and the address is compared against
SSPADD. It is also compared to the general call
address, fixed in hardware.
FIGURE 9-13: SLAVE MODE GENERAL CALL ADDRESS SEQUENCE (7 OR 10-BIT MODE)
Address is compared to General Call Address
after ACK, set interrupt flag
Receiving data
D5 D4 D3 D2 D1
ACK
9
R/W = 0
ACK
General Call Address
SDA
SCL
D7 D6
D0
8
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
S
SSPIF
BF
(SSPSTAT<0>)
Cleared in software
SSPBUF is read
SSPOV
(SSPCON<6>)
’0’
’1’
GCEN
(SSPCON2<7>)
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 83
PIC16C717/770/771
9.2.3
SLEEP OPERATION
from a reset or when the MSSP module is disabled.
Control of the I2C bus may be taken when the P bit is
set, or the bus is idle with both the S and P bits clear.
While in sleep mode, the I2C module can receive
addresses or data, and when an address match or
complete byte transfer occurs, wake the processor from
sleep (if the SSP interrupt bit is enabled).
In master mode, the SCL and SDA lines are manipu-
lated by the MSSP hardware.
The following events will cause SSP Interrupt Flag bit,
SSPIF, to be set (SSP Interrupt if enabled):
9.2.4
EFFECTS OF A RESET
• START condition
A reset disables the MSSP module and terminates the
current transfer.
• STOP condition
• Data transfer byte transmitted/received
• Acknowledge transmit
• Repeated Start
9.2.5
MASTER MODE
Master mode operation is supported by interrupt gen-
eration on the detection of the START and STOP con-
ditions. The STOP (P) and START (S) bits are cleared
2
FIGURE 9-14: MSSP BLOCK DIAGRAM (I C MASTER MODE)
Internal
Data Bus
SSPM<3:0>,
SSPADD<6:0>
Read
Write
SSPBUF
SSPSR
Baud
Rate
Generator
SDA
Shift
Clock
SDA in
MSb
LSb
Start bit, Stop bit,
Acknowledge
Generate
SCL
Start bit detect,
Stop bit detect
Write collision detect
Clock Arbitration
State counter for
end of XMIT/RCV
SCL in
Bus Collision
Set/Reset, S, P, WCOL (SSPSTAT)
Set SSPIF, BCLIF
Reset ACKSTAT, PEN (SSPCON2)
DS41120A-page 84
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.6
MULTI-MASTER OPERATION
9.2.7.1
I2C MASTER MODE OPERATION
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 MSSP module is disabled. Control of the I2C
bus may be taken when bit P (SSPSTAT<4>) is set, or
the bus is idle with both the S and P bits clear. When
the bus is busy, enabling the SSP Interrupt will gener-
ate the interrupt when the STOP condition occurs.
The master device generates all of the serial clock
pulses and the START and STOP conditions. A trans-
fer is ended with a STOP condition or with a Repeated
Start condition. Since the Repeated Start condition is
also the beginning of the next serial transfer, the I2C
bus will not be released.
In Master Transmitter mode, serial data is output
through SDA, while SCL outputs the serial clock. The
first byte transmitted contains the slave address of the
receiving device (7 bits) and the Read/Write (R/W) bit.
In this case, the R/W bit will be logic '0'. Serial data is
transmitted 8 bits at a time. After each byte is transmit-
ted, an acknowledge bit is received. START and STOP
conditions are output to indicate the beginning and the
end of a serial transfer.
In multi-master operation, the SDA line must be moni-
tored for arbitration to see if the signal level is the
expected output level. This check is performed in hard-
ware, with the result placed in the BCLIF bit.
The states where arbitration can be lost are:
• Address Transfer
In Master receive mode, the first byte transmitted con-
tains the slave address of the transmitting device
(7 bits) and the R/W bit. In this case the R/W bit will be
logic '1'. Thus the first byte transmitted is a 7-bit slave
address followed by a '1' to indicate receive bit. Serial
data is received via SDA while SCL outputs the serial
clock. Serial data is received 8 bits at a time. After each
byte is received, an acknowledge bit is transmitted.
START and STOP conditions indicate the beginning
and end of transmission.
• Data Transfer
• A Start Condition
• A Repeated Start Condition
• An Acknowledge Condition
9.2.7
I2C MASTER OPERATION SUPPORT
Master Mode is enabled by setting and clearing the
appropriate SSPM bits in SSPCON and by setting the
SSPEN bit. Once master mode is enabled, the user
has six options.
The baud rate generator used for SPI mode operation
is now used to set the SCL clock frequency for either
100 kHz, 400 kHz, or 1 MHz I2C operation. The baud
rate generator reload value is contained in the lower 7
bits of the SSPADD register. The baud rate generator
will automatically begin counting on a write to the SSP-
BUF. Once the given operation is complete (i.e. trans-
mission of the last data bit is followed by ACK), the
internal clock will automatically stop counting and the
SCL pin will remain in its last state
- Assert a start condition on SDA and SCL.
- Assert a Repeated Start condition on SDA and
SCL.
- Write to the SSPBUF register initiating trans-
mission of data/address.
- Generate a stop condition on SDA and SCL.
- Configure the I2C port to receive data.
- Generate an Acknowledge condition at the end
of a received byte of data.
A typical transmit sequence would go as follows:
Note: The MSSP Module, when configured in I2C
Master Mode, does not allow queueing of
events. For instance, the user is not
allowed to initiate a start condition and
immediately write the SSPBUF register to
initiate transmission before the START
condition is complete. In this case, the
SSPBUF will not be written to, and the
WCOL bit will be set, indicating that a write
to the SSPBUF did not occur.
a) The user generates a Start Condition by setting
the START enable bit (SEN) in SSPCON2.
b) SSPIF is set. The module will wait the required
start time before any other operation takes
place.
c) The user loads the SSPBUF with address to
transmit.
d) Address is shifted out the SDA pin until all 8 bits
are transmitted.
e) The MSSP Module shifts in the ACK bit from the
slave device, and writes its value into the
SSPCON2 register ( SSPCON2<6>).
f) The module generates an interrupt at the end of
the ninth clock cycle by setting SSPIF.
g) The user loads the SSPBUF with eight bits of
data.
h) DATA is shifted out the SDA pin until all 8 bits
are transmitted.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 85
PIC16C717/770/771
i) The MSSP Module shifts in the ACK bit from the
slave device and writes its value into the
SSPCON2 register ( SSPCON2<6>).
In I2C master mode, the BRG is reloaded automatically.
If Clock Arbitration is taking place for instance, the BRG
will be reloaded when the SCL pin is sampled high
(Figure 9-16).
j) The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the SSPIF
bit.
FIGURE 9-15: BAUD RATE GENERATOR
BLOCK DIAGRAM
k) The user generates a STOP condition by setting
the STOP enable bit PEN in SSPCON2.
SSPM<3:0>
SSPADD<6:0>
l) Interrupt is generated once the STOP condition
is complete.
SSPM<3:0>
SCL
Reload
Control
9.2.8
BAUD RATE GENERATOR
Reload
In I2C master mode, the reload value for the BRG is
located in the lower 7 bits of the SSPADD register
(Figure 9-15). When the BRG is loaded with this value,
the BRG counts down to 0 and stops until another
reload has taken place. The BRG count is decremented
twice per instruction cycle (TCY) on the Q2 and Q4
clock.
FOSC/4
BRG Down Counter
CLKOUT
FIGURE 9-16: BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
SDA
DX
DX-1
SCL allowed to transition high
SCL de-asserted but slave holds
SCL low (clock arbitration)
SCL
BRG decrements
(on Q2 and Q4 cycles)
BRG
value
03h
02h
01h
00h (hold off)
03h
02h
SCL is sampled high, reload takes
place, and BRG starts its count.
BRG
reload
DS41120A-page 86
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.9
I2C MASTER MODE START CONDITION
TIMING
9.2.9.1
WCOL STATUS FLAG
If the user writes the SSPBUF when an START
sequence is in progress, then WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
To initiate a START condition, the user sets the start
condition enable bit, SEN (SSPCON2<0>). If the SDA
and SCL pins are sampled high, the baud rate genera-
tor is re-loaded with the contents of SSPADD<6:0>,
and starts its count. If SCL and SDA are both sampled
high when the baud rate generator times out (TBRG),
the SDA pin is driven low. The action of the SDA being
driven low while SCL is high is the START condition,
and causes the S bit (SSPSTAT<3>) to be set. Follow-
ing this, the baud rate generator is reloaded with the
contents of SSPADD<6:0> and resumes its count.
When the baud rate generator times out (TBRG), the
SEN bit (SSPCON2<0>) will be automatically cleared
by hardware, the baud rate generator is suspended
leaving the SDA line held low, and the START condition
is complete.
Note: Because queueing of events is not
allowed, writing to the lower 5 bits of
SSPCON2 is disabled until the START
condition is complete.
Note: If at the beginning of START condition, the
SDA and SCL pins are already sampled
low, or if during the START condition, the
SCL line is sampled low before the SDA
line is driven low, a bus collision occurs, the
Bus Collision Interrupt Flag (BCLIF) is set,
the START condition is aborted, and the
I2C module is reset into its IDLE state.
FIGURE 9-17: FIRST START BIT TIMING
Set S bit (SSPSTAT<3>)
Write to SEN bit occurs here.
SDA = 1,
At completion of start bit,
Hardware clears SEN bit
and sets SSPIF bit
SCL = 1
TBRG
TBRG
Write to SSPBUF occurs here
2nd Bit
1st Bit
SDA
TBRG
SCL
TBRG
S
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 87
PIC16C717/770/771
FIGURE 9-18: START CONDITION FLOWCHART
SSPEN = 1,
SSPCON<3:0> = 1000
Idle Mode
SEN (SSPCON2<0> = 1)
Bus collision detected,
Set BCLIF,
No
SDA = 1?
SCL = 1?
Release SCL,
Clear SEN
Yes
Load BRG with
SSPADD<6:0>
No
No
Yes
No
BRG
Rollover?
SCL= 0?
SDA = 0?
Yes
Yes
Reset BRG
Force SDA = 0,
Load BRG with
SSPADD<6:0>,
Set S bit.
BRG
rollover?
No
No
SCL = 0?
Yes
Yes
Reset BRG
Force SCL = 0,
Start Condition Done,
Clear SEN
and set SSPIF
DS41120A-page 88
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.10 I2C MASTER MODE REPEATED START
CONDITION TIMING
Immediately following the SSPIF bit getting set, the
user may write the SSPBUF with the 7-bit address in
7-bit mode, or the default first address in 10-bit mode.
After the first eight bits are transmitted and an ACK is
received, the user may then transmit an additional eight
bits of address (10-bit mode) or eight bits of data (7-bit
mode).
A Repeated Start condition occurs when the RSEN bit
(SSPCON2<1>) is set high and the I2C module is in the
idle state. When the RSEN bit is set, the SCL pin is
asserted low. When the SCL pin is sampled low, the
baud rate generator is loaded with the contents of
SSPADD<6:0>, and begins counting. The SDA pin is
released (brought high) for one baud rate generator
count (TBRG). When the baud rate generator times out,
if SDA is sampled high, the SCL pin will be de-asserted
(brought high). When SCL is sampled high the baud
rate generator is re-loaded with the contents of
SSPADD<6:0> and begins counting. SDA and SCL
must be sampled high for one TBRG. This action is then
followed by assertion of the SDA pin (SDA is low) for
one TBRG while SCL is high. Following this, the RSEN
bit in the SSPCON2 register will be automatically
cleared, and the baud rate generator is not reloaded,
leaving the SDA pin held low. As soon as a start con-
dition is detected on the SDA and SCL pins, the S bit
(SSPSTAT<3>) will be set. The SSPIF bit will not be set
until the baud rate generator has timed-out.
9.2.10.1 WCOL STATUS FLAG
If the user writes the SSPBUF when a Repeated Start
sequence is in progress, then WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
Note: Because queueing of events is not
allowed, writing of the lower 5 bits of
SSPCON2 is disabled until the Repeated
Start condition is complete.
Note 1: If RSEN is set while any other event is in
progress, it will not take effect.
Note 2: A bus collision during the Repeated Start
condition occurs if:
• SDA is sampled low when SCL goes
from low to high.
• SCL goes low before SDA is asserted
low. This may indicate that another
master is attempting to transmit a
data "1".
FIGURE 9-19: REPEAT START CONDITION WAVEFORM
Set S (SSPSTAT<3>)
Write to SSPCON2
SDA = 1,
At completion of start bit,
hardware clear RSEN bit
and set SSPIF
occurs here.
SCL = 1
SDA = 1,
SCL (no change)
TBRG TBRG
TBRG
1st Bit
SDA
Write to SSPBUF occurs here.
TBRG
Falling edge of ninth clock
End of Xmit
SCL
TBRG
Sr = Repeated Start
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 89
PIC16C717/770/771
FIGURE 9-20: REPEATED START CONDITION FLOWCHART (PAGE 1)
Start
Idle Mode,
SSPEN = 1,
SSPCON<3:0> = 1000
B
RSEN = 1
Force SCL = 0
No
SCL = 0?
Yes
Release SDA,
Load BRG with
SSPADD<6:0>
No
BRG
rollover?
Yes
Release SCL
(Clock Arbitration)
No
SCL = 1?
Yes
Bus Collision,
Set BCLIF,
Release SDA,
Clear RSEN
No
SDA = 1?
Yes
Load BRG with
SSPADD<6:0>
C
A
DS41120A-page 90
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 9-21: REPEATED START CONDITION FLOWCHART (PAGE 2)
B
C
A
Yes
No
No
No
BRG
rollover?
SDA = 0?
SCL = 1?
Yes
Yes
Reset BRG
Force SDA = 0,
Load BRG with
SSPADD<6:0>
Set S
No
No
BRG
rollover?
SCL = ’0’?
Yes
Yes
Force SCL = 0,
Repeated Start
condition done,
Clear RSEN,
Reset BRG
Set SSPIF.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 91
PIC16C717/770/771
9.2.11 I2C MASTER MODE TRANSMISSION
9.2.11.3 ACKSTAT STATUS FLAG
Transmission of a data byte, a 7-bit address, or either
half of a 10-bit address is accomplished by simply writ-
ing a value to the SSPBUF register. This action will set
the buffer full flag (BF) and allow the baud rate genera-
tor to begin counting and start the next transmission.
Each bit of address/data will be shifted out onto the
SDA pin after the falling edge of SCL is asserted (see
data hold time spec). SCL is held low for one baud
rate generator roll over count (TBRG). Data should be
valid before SCL is released high (see data setup time
spec). When the SCL pin is released high, it is held that
way for TBRG, the data on the SDA pin must remain
stable for that duration and some hold time after the
next falling edge of SCL. After the eighth bit is shifted
out (the falling edge of the eighth clock), the BF flag is
cleared and the master releases SDA allowing the
slave device being addressed to respond with an ACK
bit during the ninth bit time, if an address match occurs
or if data was received properly. The status of ACK is
read into the ACKDT on the falling edge of the ninth
clock. If the master receives an acknowledge, the
acknowledge status bit (ACKSTAT) is cleared. If not,
the bit is set. After the ninth clock the SSPIF is set, and
the master clock (baud rate generator) is suspended
until the next data byte is loaded into the SSPBUF leav-
ing SCL low and SDA unchanged (Figure 9-23).
In transmit mode, the ACKSTAT bit (SSPCON2<6>) is
cleared when the slave has sent an acknowledge
(ACK = 0), and is set when the slave does not acknowl-
edge (ACK = 1). A slave sends an acknowledge when
it has recognized its address (including a general call),
or when the slave has properly received its data.
After the write to the SSPBUF, each bit of address will
be shifted out on the falling edge of SCL until all seven
address bits and the R/W bit are completed. On the fall-
ing edge of the eighth clock, the master will de-assert
the SDA pin allowing the slave to respond with an
acknowledge. On the falling edge of the ninth clock, the
master will sample the SDA pin to see if the address
was recognized by a slave. The status of the ACK bit is
loaded into the ACKSTAT status bit (SSPCON2<6>).
Following the falling edge of the ninth clock transmis-
sion of the address, the SSPIF is set, the BF flag is
cleared, and the baud rate generator is turned off until
another write to the SSPBUF takes place, holding SCL
low and allowing SDA to float.
9.2.11.1 BF STATUS FLAG
In transmit mode, the BF bit (SSPSTAT<0>) is set when
the CPU writes to SSPBUF and is cleared when all 8
bits are shifted out.
9.2.11.2 WCOL STATUS FLAG
If the user writes the SSPBUF when a transmit is
already in progress (i.e. SSPSR is still shifting out a
data byte), then WCOL is set and the contents of the
buffer are unchanged (the write doesn’t occur).
WCOL must be cleared in software.
DS41120A-page 92
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 9-22: MASTER TRANSMIT FLOWCHART
Idle Mode
Write SSPBUF
Num_Clocks = 0,
BF = 1
Force SCL = 0
Release SDA so
slave can drive ACK,
Force BF = 0
Yes
Num_Clocks
= 8?
No
Load BRG with
SSPADD<6:0>,
start BRG count
Load BRG with
SSPADD<6:0>,
start BRG count,
SDA = Current Data bit
No
BRG
rollover?
BRG
rollover?
No
Yes
Yes
Force SCL = 1,
Stop BRG
Stop BRG,
Force SCL = 1
(Clock Arbitration)
No
(Clock Arbitration)
SCL = 1?
Yes
No
SCL = 1?
Yes
Read SDA and place into
ACKSTAT bit (SSPCON2<6>)
Bus collision detected
Set BCLIF, hold prescale off,
Clear XMIT enable
No
SDA =
Data bit?
Load BRG with
SSPADD<6:0>,
count high time
Yes
Load BRG with
SSPADD<6:0>,
count SCL high time
No
Rollover?
Yes
No
No
No
SDA =
Data bit?
BRG
rollover?
Yes
SCL = 0?
Force SCL = 0,
Set SSPIF
Yes
Yes
Reset BRG
Num_Clocks
= Num_Clocks + 1
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 93
PIC16C717/770/771
2
FIGURE 9-23: I C MASTER MODE TIMING (TRANSMISSION, 7 OR 10-BIT ADDRESS)
DS41120A-page 94
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.12 I2C MASTER MODE RECEPTION
Master mode reception is enabled by setting the
receive enable bit, RCEN (SSPCON2<3>).
Note: The MSSP Module must be in an IDLE
STATE before the RCEN bit is set, or the
RCEN bit will be disregarded.
The baud rate generator begins counting, and on each
rollover, the state of the SCL pin changes (high to low/
low to high) and data is shifted into the SSPSR. After
the falling edge of the eighth clock, the receive enable
flag is automatically cleared, the contents of the
SSPSR are loaded into the SSPBUF, the BF flag is set,
the SSPIF is set, and the baud rate generator is sus-
pended from counting, holding SCL low. The SSP is
now in IDLE state, awaiting the next command. When
the buffer is read by the CPU, the BF flag is automati-
cally cleared. The user can then send an acknowledge
bit at the end of reception, by setting the acknowledge
sequence enable bit, ACKEN (SSPCON2<4>).
9.2.12.1 BF STATUS FLAG
In receive operation, BF is set when an address or data
byte is loaded into SSPBUF from SSPSR. It is cleared
when SSPBUF is read.
9.2.12.2 SSPOV STATUS FLAG
In receive operation, SSPOV is set when 8 bits are
received into the SSPSR, and the BF flag is already set
from a previous reception.
9.2.12.3 WCOL STATUS FLAG
If the user writes the SSPBUF when a receive is
already in progress (i.e. SSPSR is still shifting in a data
byte), then WCOL is set and the contents of the buffer
are unchanged (the write doesn’t occur).
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 95
PIC16C717/770/771
FIGURE 9-24: MASTER RECEIVER FLOWCHART
Idle mode
RCEN = 1
Num_Clocks = 0,
Release SDA
Force SCL=0,
Load BRG w/
SSPADD<6:0>,
start count
BRG
No
rollover?
Yes
Release SCL
(Clock Arbitration)
No
SCL = 1?
Yes
Sample SDA,
Shift data into SSPSR
Load BRG with
SSPADD<6:0>,
start count.
No
No
BRG
SCL = 0?
Yes
rollover?
Yes
Num_Clocks
= Num_Clocks + 1
No
Num_Clocks
= 8?
Yes
Force SCL = 0,
Set SSPIF,
Set BF.
Move contents of SSPSR
into SSPBUF,
Clear RCEN.
DS41120A-page 96
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
2
FIGURE 9-25: I C MASTER MODE TIMING (RECEPTION 7-BIT ADDRESS)
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 97
PIC16C717/770/771
9.2.13 ACKNOWLEDGE SEQUENCE TIMING
the baud rate generator counts for TBRG . The SCL pin
is then pulled low. Following this, the ACKEN bit is
automatically cleared, the baud rate generator is turned
off, and the MSSP module then goes into IDLE mode.
(Figure 9-26)
An acknowledge sequence is enabled by setting the
acknowledge
sequence
enable
bit,
ACKEN
(SSPCON2<4>). When this bit is set, the SCL pin is
pulled low and the contents of the acknowledge data
bit is presented on the SDA pin. If the user wishes to
generate an acknowledge, then the ACKDT bit should
be cleared. If not, the user should set the ACKDT bit
before starting an acknowledge sequence. The baud
rate generator then counts for one rollover period
(TBRG), and the SCL pin is de-asserted (pulled high).
When the SCL pin is sampled high (clock arbitration),
9.2.13.1 WCOL STATUS FLAG
If the user writes the SSPBUF when an acknowledged
sequence is in progress, then WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
FIGURE 9-26: ACKNOWLEDGE SEQUENCE WAVEFORM
Acknowledge sequence starts here,
Write to SSPCON2
ACKEN automatically cleared
ACKEN = 1, ACKDT = 0
TBRG
TBRG
SDA
SCL
D0
ACK
8
9
SSPIF
Cleared in
software
Set SSPIF at the end
of receive
Cleared in
software
Set SSPIF at the end
of acknowledge sequence
Note: TBRG = one baud rate generator period.
DS41120A-page 98
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 9-27: ACKNOWLEDGE FLOWCHART
Idle mode
Set ACKEN
Force SCL = 0
BRG
Yes
rollover?
No
No
SCL = 0?
Yes
Force SCL = 0,
Clear ACKEN,
Set SSPIF
Yes
SCL = 0?
No
Reset BRG
Drive ACKDT bit
(SSPCON2<5>)
onto SDA pin,
Load BRG with
SSPADD<6:0>,
start count.
No
ACKDT = 1?
Yes
No
BRG
rollover?
Yes
SDA = 1?
No
Yes
Force SCL = 1
Bus collision detected,
Set BCLIF,
Release SCL,
Clear ACKEN
No
SCL = 1?
Yes
(Clock Arbitration)
Load BRG with
SSPADD <6:0>,
start count.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 99
PIC16C717/770/771
9.2.14 STOP CONDITION TIMING
while SCL is high, the P bit (SSPSTAT<4>) is set. A
TBRG later the PEN bit is cleared and the SSPIF bit is
set (Figure 9-28).
A stop bit is asserted on the SDA pin at the end of a
receive/transmit by setting the Stop Sequence Enable
bit PEN (SSPCON2<2>). At the end of a receive/trans-
mit, the SCL line is held low after the falling edge of the
ninth clock. When the PEN bit is set, the master will
assert the SDA line low . When the SDA line is sam-
pled low, the baud rate generator is reloaded and
counts down to 0. When the baud rate generator times
out, the SCL pin will be brought high and one TBRG
(baud rate generator rollover count) later, the SDA pin
will be de-asserted. When the SDA pin is sampled high
Whenever the firmware decides to take control of the
bus, it will first determine if the bus is busy by checking
the S and P bits in the SSPSTAT register. If the bus is
busy, then the CPU can be interrupted (notified) when
a Stop bit is detected (i.e. bus is free).
9.2.14.1 WCOL STATUS FLAG
If the user writes the SSPBUF when a STOP sequence
is in progress, then WCOL is set and the contents of the
buffer are unchanged (the write doesn’t occur).
FIGURE 9-28: STOP CONDITION RECEIVE OR TRANSMIT MODE
SCL = 1 for TBRG, followed by SDA = 1 for TBRG
after SDA sampled high. P bit (SSPSTAT<4>) is set
Write to SSPCON2
Set PEN
PEN bit (SSPCON2<2>) is cleared by
hardware and the SSPIF bit is set
Falling edge of
9th clock
TBRG
TBRG
SCL
ACK
SDA
P
TBRG
TBRG
SCL brought high after TBRG
SDA asserted low before rising edge of clock
to setup stop condition.
Note: TBRG = one baud rate generator period.
DS41120A-page 100
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 9-29: STOP CONDITION FLOWCHART
Idle Mode,
SSPEN = 1,
SSPCON<3:0> = 1000
PEN = 1
Start BRG
Force SDA = 0
SCL doesn’t change
No
BRG
rollover?
Yes
No
SDA = 0?
Release SDA,
Start BRG
Yes
Start BRG
No
BRG
rollover?
No
BRG
rollover?
Yes
Bus Collision detected,
Set BCLIF,
No
Yes
P bit Set?
Yes
Clear PEN
De-assert SCL,
SCL = 1
SDA going from
0 to 1 while SCL = 1
Set SSPIF,
Stop Condition done
PEN cleared.
(Clock Arbitration)
No
SCL = 1?
Yes
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 101
PIC16C717/770/771
9.2.15 CLOCK ARBITRATION
9.2.16 SLEEP OPERATION
Clock arbitration occurs when the master, during any
receive, transmit or repeated start/stop condition, de-
asserts the SCL pin (SCL allowed to float high). When
the SCL pin is allowed to float high, the baud rate gen-
erator (BRG) is suspended from counting until the SCL
pin is actually sampled high. When the SCL pin is sam-
pled high, the baud rate generator is reloaded with the
contents of SSPADD<6:0> and begins counting. This
ensures that the SCL high time will always be at least
one BRG rollover count in the event that the clock is
held low by an external device (Figure 9-30).
While in sleep mode, the I2C module can receive
addresses or data, and when an address match or
complete byte transfer occurs, wake the processor from
sleep ( if the SSP interrupt is enabled).
9.2.17 EFFECTS OF A RESET
A reset disables the MSSP module and terminates the
current transfer.
FIGURE 9-30: CLOCK ARBITRATION TIMING IN MASTER TRANSMIT MODE
BRG overflow,
Release SCL,
If SCL = 1 Load BRG with
SSPADD<6:0>, and start count
to measure high time interval
BRG overflow occurs,
Release SCL, Slave device holds SCL low.
SCL = 1 BRG starts counting
clock high interval.
SCL
SDA
SCL line sampled once every machine cycle (TOSC • 4).
Hold off BRG until SCL is sampled high.
TBRG
TBRG
TBRG
DS41120A-page 102
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.18 MULTI -MASTER COMMUNICATION, BUS
COLLISION, AND BUS ARBITRATION
If a START, Repeated Start, STOP or Acknowledge
condition was in progress when the bus collision
occurred, the condition is aborted, the SDA and SCL
lines are de-asserted, and the respective control bits in
the SSPCON2 register are cleared. When the user
services the bus collision interrupt service routine, and
if the I2C bus is free, the user can resume communica-
tion by asserting a START condition.
Multi-Master mode support is achieved by bus arbitra-
tion. When the master outputs address/data bits onto
the SDA pin, arbitration takes place when the master
outputs a ’1’ on SDA by letting SDA float high and
another master asserts a ’0’. When the SCL pin floats
high, data should be stable. If the expected data on
SDA is a ’1’ and the data sampled on the SDA pin = ’0’,
then a bus collision has taken place. The master will
set the Bus Collision Interrupt Flag, BCLIF, and reset
the I2C port to its IDLE state. (Figure 9-31).
The Master will continue to monitor the SDA and SCL
pins, and if a STOP condition occurs, the SSPIF bit will
be set.
A write to the SSPBUF will start the transmission of
data at the first data bit, regardless of where the trans-
mitter left off when bus collision occurred.
If a transmit was in progress when the bus collision
occurred, the transmission is halted, the BF flag is
cleared, the SDA and SCL lines are de-asserted, and
the SSPBUF can be written to. When the user services
the bus collision interrupt service routine, and if the I2C
bus is free, the user can resume communication by
asserting a START condition.
In multi-master mode, the interrupt generation on the
detection of start and stop conditions allows the deter-
mination of when the bus is free. Control of the I2C bus
can be taken when the P bit is set in the SSPSTAT reg-
ister, or the bus is idle and the S and P bits are cleared.
FIGURE 9-31: BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE
Sample SDA. While SCL is high
data doesn’t match what is driven
by the master.
SDA line pulled low
by another source
Data changes
while SCL = 0
Bus collision has occurred.
SDA released
by master
SDA
SCL
Set bus collision
interrupt.
BCLIF
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 103
PIC16C717/770/771
9.2.18.1 BUS COLLISION DURING A START
CONDITION
while SDA is high, a bus collision occurs, because it is
assumed that another master is attempting to drive a
data ’1’ during the START condition.
During a START condition, a bus collision occurs if:
If the SDA pin is sampled low during this count, the
BRG is reset and the SDA line is asserted early
(Figure 9-34). If however a ’1’ is sampled on the SDA
pin, the SDA pin is asserted low at the end of the BRG
count. The baud rate generator is then reloaded and
counts down to 0, and during this time, if the SCL pins
is sampled as ’0’, a bus collision does not occur. At the
end of the BRG count the SCL pin is asserted low.
a) SDA or SCL are sampled low at the beginning of
the START condition (Figure 9-32).
b) SCL is sampled low before SDA is asserted low.
(Figure 9-33).
During a START condition both the SDA and the SCL
pins are monitored.
If:
Note: The reason that bus collision is not a factor
during a START condition is that no two
bus masters can assert a START condition
at the exact same time. Therefore, one
master will always assert SDA before the
other. This condition does not cause a bus
collision, because the two masters must be
allowed to arbitrate the first address follow-
ing the START condition. If the address is
the same, arbitration must be allowed to
continue into the data portion, REPEATED
START or STOP conditions.
the SDA pin is already low
or the SCL pin is already low,
then:
the START condition is aborted,
and the BCLIF flag is set,
and the SSP module is reset to its IDLE state
(Figure 9-32).
The START condition begins with the SDA and SCL
pins de-asserted. When the SDA pin is sampled high,
the baud rate generator is loaded from SSPADD<6:0>
and counts down to 0. If the SCL pin is sampled low
FIGURE 9-32: BUS COLLISION DURING START CONDITION (SDA ONLY)
SDA goes low before the SEN bit is set.
Set BCLIF,
S bit and SSPIF set because
SDA = 0, SCL = 1
SDA
SCL
Set SEN, enable start
condition if SDA = 1, SCL=1
SEN cleared automatically because of bus collision.
SSP module reset into idle state.
SEN
SDA sampled low before
START condition.
Set BCLIF.
S bit and SSPIF set because
SDA = 0, SCL = 1
BCLIF
SSPIF and BCLIF are
cleared in software.
S
SSPIF
SSPIF and BCLIF are
cleared in software.
DS41120A-page 104
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 9-33: BUS COLLISION DURING START CONDITION (SCL = 0)
SDA = 0, SCL = 1
TBRG
TBRG
SDA
SCL
SEN
Set SEN, enable start
sequence if SDA = 1, SCL = 1
SCL = 0 before SDA = 0,
Bus collision occurs, Set BCLIF.
SCL = 0 before BRG time out,
Bus collision occurs, Set BCLIF.
BCLIF
Interrupts cleared
in software.
S
’0’
’0’
’0’
’0’
SSPIF
FIGURE 9-34: BRG RESET DUE TO SDA COLLISION DURING START CONDITION
SDA = 0, SCL = 1
Set S
Set SSPIF
Less than TBRG
TBRG
SDA pulled low by other master.
Reset BRG and assert SDA
SDA
SCL
s
SCL pulled low after BRG
Timeout
SEN
Set SEN, enable start
sequence if SDA = 1, SCL = 1
’0’
BCLIF
S
SSPIF
Interrupts cleared
in software.
SDA = 0, SCL = 1
Set SSPIF
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 105
PIC16C717/770/771
9.2.18.2 BUS COLLISION DURING A REPEATED
START CONDITION
however SDA is sampled high, then the BRG is
reloaded and begins counting. If SDA goes from high
to low before the BRG times out, no bus collision
occurs, because no two masters can assert SDA at
exactly the same time.
During a Repeated Start condition, a bus collision
occurs if:
a) A low level is sampled on SDA when SCL goes
from low level to high level.
If, however, SCL goes from high to low before the BRG
times out and SDA has not already been asserted, then
a bus collision occurs. In this case, another master is
attempting to transmit a data ’1’ during the Repeated
Start condition.
b) SCL goes low before SDA is asserted low, indi-
cating that another master is attempting to trans-
mit a data ’1’.
When the user de-asserts SDA and the pin is allowed
to float high, the BRG is loaded with SSPADD<6:0>,
and counts down to 0. The SCL pin is then de-
asserted, and when sampled high, the SDA pin is sam-
pled. If SDA is low, a bus collision has occurred (i.e.
another master is attempting to transmit a data ’0’). If
If at the end of the BRG time out both SCL and SDA are
still high, the SDA pin is driven low, the BRG is
reloaded, and begins counting. At the end of the count,
regardless of the status of the SCL pin, the SCL pin is
driven low and the Repeated Start condition is com-
plete (Figure 9-35).
FIGURE 9-35: BUS COLLISION DURING A REPEATED START CONDITION (CASE 1)
SDA
SCL
Sample SDA when SCL goes high.
If SDA = 0, set BCLIF and release SDA and SCL
RSEN
BCLIF
Cleared in software
’0’
’0’
’0’
S
’0’
SSPIF
FIGURE 9-36: BUS COLLISION DURING REPEATED START CONDITION (CASE 2)
TBRG
TBRG
SDA
SCL
SCL goes low before SDA,
Set BCLIF. Release SDA and SCL
BCLIF
RSEN
Interrupt cleared
in software
’0’
’0’
’0’
’0’
S
SSPIF
DS41120A-page 106
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
9.2.18.3 BUS COLLISION DURING A STOP
CONDITION
The STOP condition begins with SDA asserted low.
When SDA is sampled low, the SCL pin is allow to float.
When the pin is sampled high (clock arbitration), the
baud rate generator is loaded with SSPADD<6:0> and
counts down to 0. After the BRG times out SDA is sam-
pled. If SDA is sampled low, a bus collision has
occurred. This is due to another master attempting to
drive a data ’0’. If the SCL pin is sampled low before
SDA is allowed to float high, a bus collision occurs.
This is another case of another master attempting to
drive a data ’0’ (Figure 9-37).
Bus collision occurs during a STOP condition if:
a) After the SDA pin has been de-asserted and
allowed to float high, SDA is sampled low after
the BRG has timed out.
b) After the SCL pin is de-asserted, SCL is sam-
pled low before SDA goes high.
FIGURE 9-37: BUS COLLISION DURING A STOP CONDITION (CASE 1)
SDA sampled
low after TBRG,
Set BCLIF
TBRG
TBRG
TBRG
SDA
SDA asserted low
SCL
PEN
BCLIF
P
’0’
’0’
’0’
’0’
SSPIF
FIGURE 9-38: BUS COLLISION DURING A STOP CONDITION (CASE 2)
TBRG
TBRG
TBRG
SDA
SCL goes low before SDA goes high
Set BCLIF
Assert SDA
SCL
PEN
BCLIF
P
’0’
’0’
SSPIF
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 107
PIC16C717/770/771
9.2.19 CONNECTION CONSIDERATIONS FOR I2C
BUS
VOL max = 0.4V at 3 mA, Rp min = (5.5-0.4)/0.003 =
1.7 kΩ. VDD as a function of Rp is shown in Figure 9-39.
The desired noise margin of 0.1VDD for the low level
limits the maximum value of Rs. Series resistors are
optional and used to improve ESD susceptibility.
For standard-mode I2C bus devices, the values of
resistors Rp and Rs in Figure 9-39 depends on the fol-
lowing parameters
The bus capacitance is the total capacitance of wire,
connections, and pins. This capacitance limits the max-
imum value of Rp due to the specified rise time
(Figure 9-39).
• Supply voltage
• Bus capacitance
• Number of connected devices
(input current + leakage current).
The SMP bit is the slew rate control enabled bit. This bit
is in the SSPSTAT register, and controls the slew rate
of the I/O pins when in I2C mode (master or slave).
The supply voltage limits the minimum value of resistor
Rp due to the specified minimum sink current of 3 mA
at VOL max = 0.4V for the specified output stages. For
example, with a supply voltage of VDD = 5V+10% and
FIGURE 9-39: SAMPLE DEVICE CONFIGURATION FOR I2C BUS
VDD + 10%
DEVICE
RP
RP
RS
RS
SDA
SCL
C =10 pF to 400 pF
b
2
Note: I C devices with input levels related to VDD must have one common supply line to which the pull-up resistor is also connected.
TABLE 9-3:
REGISTERS ASSOCIATED WITH I2C OPERATION
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR, BOR MCLR, WDT
0Bh, 8Bh,
10Bh,18Bh
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
0Ch
8Ch
0Dh
8Dh
13h
14h
91h
94h
PIR1
PIE1
—
ADIF
ADIE
—
—
—
—
—
—
—
—
—
SSPIF
SSPIE
BCLIF
BCLIE
CCP1IF
CCP1IE
—
TMR2IF
TMR2IE
—
TMR1IF -0-- 0000 -0-- 0000
TMR1IE -0-- 0000 -0-- 0000
CCP2IF 0--- 0--0 0--- 0--0
CCP2IE 0--- 0--0 0--- 0--0
xxxx xxxx uuuu uuuu
—
PIR2
LVDIF
LVDIE
PIE2
—
—
—
SSPBUF
SSPCON
SSPCON2
SSPSTAT
Synchronous Serial Port Receive Buffer/Transmit Register
WCOL
SSPOV
SSPEN
CKP
SSPM3
RCEN
S
SSPM2
PEN
SSPM1
RSEN
UA
SSPM0
SEN
BF
0000 0000 0000 0000
0000 0000 0000 0000
GCEN ACKSTAT ACKDT ACKEN
SMP CKE D/A
P
R/W
0000 0000 0000 0000
2
Legend: x= unknown, u= unchanged, -= unimplemented read as ’0’. Shaded cells are not used by the MSSP in I C mode.
DS41120A-page 108
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
The source for the reference voltages comes from the
bandgap reference circuit. The bandgap circuit is ener-
gized anytime the reference voltage is required by the
other sub-modules, and is powered down when not in
use. The control registers for this module are LVDCON
and REFCON, as shown in Register 10-1 and
Figure 10-2.
10.0 VOLTAGE REFERENCE
MODULE AND LOW-VOLTAGE
DETECT
The Voltage Reference module provides reference volt-
ages for the Brown-out Reset circuitry, the Low-voltage
Detect circuitry and the A/D converter.
REGISTER 10-1: LOW-VOLTAGE DETECT CONTROL REGISTER (LVDCON: 9Ch)
U-0
U-0
R-0
R/W-0
R/W-0
R/W-1
R/W-0
R/W-1
—
—
BGST
LVDEN
LV3
LV2
LV1
LV0
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’
bit 5:
BGST: Bandgap Stable Status Flag bit
1= Indicates that the bandgap voltage is stable, and LVD interrupt is reliable
0= Indicates that the bandgap voltage is not stable, and LVD interrupt should not be enabled
bit 4:
LVDEN: Low-voltage Detect Power Enable bit
1= Enables LVD, powers up bandgap circuit and reference generator
0= Disables LVD, powers down bandgap circuit if unused by BOR or VRH/VRL
bit 3-0: LV<3:0>: Low Voltage Detection Limit bits (1)
1111= External analog input is used
1110= 4.5V
1101= 4.2V
1100= 4.0V
1011= 3.8V
1010= 3.6V
1001= 3.5V
1000= 3.3V
0111= 3.0V
0110= 2.8V
0101= 2.7V
0100= 2.5V
0011= Reserved. Do not use.
0010= Reserved. Do not use.
0001= Reserved. Do not use.
0000= Reserved. Do not use.
Note 1: These are the minimum trip points for the LVD. See Table 15-3 for the trip point tolerances. Selection of
reserved setting may result in an inadvertent interrupt.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 109
PIC16C717/770/771
REGISTER 10-2: VOLTAGE REFERENCE CONTROL REGISTER (REFCON: 9BH)
R/W-0
R/W-0
R/W-0
R/W-0
U-0
U-0
U-0
U-0
VRHEN
VRLEN
VRHOEN
VRLOEN
—
—
—
—
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:
VRHEN: Voltage Reference High Enable bit (VRH = 4.096V nominal)
1= Enabled, powers up reference generator
0= Disabled, powers down reference generator if unused by LVD, BOR, or VRL
VRLEN: Voltage Reference Low Enable bit (VRL = 2.048V nominal)
1= Enabled, powers up reference generator
0= Disabled, powers down reference generator if unused by LVD, BOR, or VRH
VRHOEN: High Voltage Reference Output Enable bit
1= Enabled, VRH analog reference is output on RA3 if enabled (VRHEN = 1)
0= Disabled, analog reference is used internally only
VRLOEN: Low Voltage Reference Output Enable bit
1= Enabled, VRL analog reference is output on RA2 if enabled (VRLEN = 1)
0= Disabled, analog reference is used internally only
bit 3-0: Unimplemented: Read as '0’
Each reference, if enabled, can be output on an exter-
nal pin by setting the VRHOEN (high reference output
enable) or VRLOEN (low reference output enable) con-
trol bit. If the reference is not enabled, the VRHOEN
and VRLOEN bits will have no effect on the corre-
sponding pin. The device specific pin can then be used
as general purpose I/O.
10.1
Bandgap Voltage Reference
The bandgap module generates a stable voltage refer-
ence of over a range of temperatures and device supply
voltages. This module is enabled anytime any of the fol-
lowing are enabled:
• Brown-out Reset
• Low-voltage Detect
Note: If VRH or VRL is enabled and the other ref-
erence (VRL or VRH), the BOR, and the
LVD modules are not enabled, the band-
gap will require a start-up time before the
bandgap reference is stable. Before using
the internal VRH or VRL reference, ensure
that the bandgap reference voltage is sta-
ble by monitoring the BGST bit in the LVD-
CON register. The voltage references will
not be reliable until the bandgap is stable
as shown by BGST being set.
• Either of the internal analog references (VRH,
VRL)
Whenever the above are all disabled, the bandgap
module is disabled and draws no current.
10.2
Internal VREF for A/D Converter
The bandgap output voltage is used to generate two
stable references for the A/D converter module. These
references are enabled in software to provide the user
with the means to turn them on and off in order to min-
imize current consumption. Each reference can be indi-
vidually enabled.
The VRH reference is enabled with control bit VRHEN
(REFCON<7>). When this bit is set, the gain amplifier
is enabled. After a specified start-up time a stable ref-
erence of 4.096V nominal is generated and can be
used by the A/D converter as a reference input.
The VRL reference is enabled by setting control bit
VRLEN (REFCON<6>). When this bit is set, the gain
amplifier is enabled. After a specified start up time a
stable reference of 2.048V nominal is generated and
can be used by the A/D converter as a reference input.
Each voltage reference is available for external use via
VRL and VRH pins.
DS41120A-page 110
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
control. This allows a user to power the module on
and off to periodically monitor the supply voltage, and
thus minimize total current consumption.
10.3
Low-voltage Detect (LVD)
This module is used to generate an interrupt when the
supply voltage falls below a specified “trip” voltage.
This module operates completely under software
FIGURE 10-1: BLOCK DIAGRAM OF LVD AND VOLTAGE REFERENCE CIRCUIT
LVDCON
REFCON
VDD
LVDEN
VRHEN + VRLEN
generates
LVDIF
RA1/AN1/LVDIN
VRH
BODEN
BGAP
VRL
LVDEN
The LVD module is enabled by setting the LVDEN bit in
the LVDCON register. The “trip point” voltage is the
minimum supply voltage level at which the device can
operate before the LVD module asserts an interrupt.
When the supply voltage is equal to or less than the trip
point, the module will generate an interrupt signal set-
ting interrupt flag bit LVDIF. If interrupt enable bit LVDIE
was set, then an interrupt is generated. The LVD inter-
rupt can wake the device from sleep. The "trip point"
voltage is software programmable to any one of 16 val-
ues, five of which are reserved (See Figure 10-1). The
trip point is selected by programming the LV<3:0> bits
(LVDCON<3:0>).
If the bandgap reference voltage is previously unused
by either the brown-out circuitry or the voltage refer-
ence circuitry, then the bandgap circuit requires a time
to start-up and become stable before a low voltage con-
dition can be reliably detected. The low-voltage inter-
rupt flag is prevented from being set until the bandgap
has reached a stable reference voltage.
When the bandgap is stable the BGST (LVDCON<5>)
bit is set indicating that the low-voltage interrupt flag bit
is released to be set if VDD is equal to or less than the
LVD trip point.
10.3.1 EXTERNAL ANALOG VOLTAGE INPUT
Note: The LVDIF bit can not be cleared until the
supply voltage rises above the LVD trip
point. If interrupts are enabled, clear the
LVDIE bit once the first LVD interrupt
occurs to prevent reentering the interrupt
service routine immediately after exiting
the ISR.
The LVD module has an additional feature that allows
the user to supply the trip voltage to the module from
an external source. This mode is enabled when
LV<3:0> = 1111. When these bits are set the compar-
ator input is multiplexed from an external input pin
(RA1/AN1/LVDIN).
Once the LV bits have been programmed for the speci-
fied trip voltage, the low-voltage detect circuitry is then
enabled by setting the LVDEN (LVDCON<4>) bit.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 111
PIC16C717/770/771
NOTES:
DS41120A-page 112
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
The A/D module has four registers. These registers
are:
11.0 ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
The analog-to-digital (A/D) converter module has six
inputs for the PIC16C717/770/771.
• A/D Result Register Low ADRESL
• A/D Result Register High ADRESH
• A/D Control Register 0 (ADCON0)
• A/D Control Register 1 (ADCON1)
The PIC16C717 analog-to-digital converter (A/D)
allows conversion of an analog input signal to a corre-
sponding 10-bit digital value, while the A/D converter
in the PIC16C770/771 allows conversion to a corre-
sponding 12-bit digital value. The A/D module has up
to 6 analog inputs, which are multiplexed into one
sample and hold. The output of the sample and hold is
the input into the converter, which generates the result
via successive approximation. The analog reference
voltages are software selectable to either the device’s
analog positive and negative supply voltages (AVDD/
AVSS), the voltage level on the VREF+ and VREF- pins,
or internal voltage references if enabled (VRH, VRL).
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.
11.1
Control Registers
The ADCON0 register, shown in Register 11-1, con-
trols the operation of the A/D module. The ADCON1
register, shown in Register 11-2, configures the func-
tions of the port pins, the voltage reference configura-
tion and the result format. The port pins can be
configured as analog inputs or as digital I/O.
The A/D converter can be triggered by setting the GO/
DONE bit, or by the special event compare mode of
the ECCP1 module. When conversion is complete, the
GO/DONE bit returns to ’0’, the ADIF bit in the PIR1
register is set, and an A/D interrupt will occur, if
enabled.
The combination of the ADRESH and ADRESL regis-
ters contain the result of the A/D conversion. The reg-
ister pair is referred to as the ADRES register. When
the A/D conversion is complete, the result is loaded
into ADRES, the GO/DONE bit (ADCON0<2>) is
cleared, and the A/D interrupt flag ADIF is set. The
block diagram of the A/D module is shown in
Figure 11-3.
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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 113
PIC16C717/770/771
REGISTER 11-1: A/D CONTROL REGISTER 0 (ADCON0: 1Fh).
R/W-0
R/W-0
R/W-0
CHS2
R/W-0
CHS1
R/W-0
CHS0
R/W-0
R/W-0
CHS3
R/W-0
ADON
ADCS1
ADCS0
GO/DONE
R =
W =
Readable bit
Writable bit
bit7
bit 0
- n = Value at POR reset
bit 7-6: ADCS<1:0>: A/D Conversion Clock Select bits
If internal VRL and/or VRH are not used for A/D reference (VCFG<2:0> = 000, 001, 011or101):
00= FOSC/2
01= FOSC/8
10= FOSC/32
11= FRC (clock derived from a dedicated RC oscillator = 1 MHz max)
If internal VRL and/or VRH are used for A/D reference (VCFG<2:0> = 010, 100, 110or111):
00= FOSC/16
01= FOSC/64
10= FOSC/256
11= FRC (clock derived from a dedicated RC oscillator = 125 kHz max)
bit 1,5-3:CHS:<3:0>: Analog Channel Select bits
0000= channel 00 (AN0)
0001= channel 01 (AN1)
0010= channel 02 (AN2)
0011= channel 03 (AN3)
0100= channel 04 (AN4)
0101= channel 05 (AN5)
0110= reserved, do not select
0111= reserved, do not select
1000= reserved, do not select
1001= reserved, do not select
1010= reserved, do not select
1011= reserved, do not select
1100= reserved, do not select
1101= reserved, do not select
1110= reserved, do not select
1111= reserved, do not select
bit 2:
bit 0:
GO/DONE: A/D Conversion Status bit
1= A/D conversion cycle in progress. Setting this bit starts an A/D conversion cycle.
This bit is automatically cleared by hardware when the A/D conversion has completed.
0= A/D conversion completed/not in progress
ADON: A/D On bit
1= A/D converter module is operating
0= A/D converter is shutoff and consumes no operating current
DS41120A-page 114
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
REGISTER 11-2: A/D CONTROL REGISTER 1 (ADCON1: 9Fh)
R/W-0
ADFM
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
VCFG2
VCFG1
VCFG0
Reserved
R =
W =
U =
Readable bit
Writable bit
Unimplemented bit, read as ‘0’
bit7
bit 0
- n = Value at POR reset
bit 7:
ADFM: A/D Result Format Select bit
1= Right justified
0= Left justified
bit 6-4: VCFG<2:0>: Voltage reference configuration bits
A/D VREF+
AVDD
A/D VREF-
AVSS
000
001
010
011
100
101
110
111
External VREF+
Internal VRH
External VREF+
Internal VRH
AVDD
External VREF-
Internal VRL
AVSS
AVSS
External VREF-
Internal VRL
AVSS
AVDD
Internal VRL
bit 3-0: Reserved: Do not use.
The value that is in the ADRESH and ADRESL regis-
ters are not modified for a Power-on Reset. The
ADRESH and ADRESL registers will contain unknown
data after a Power-on Reset.
The A/D conversion results can be left justified (ADFM
bit cleared), or right justified (ADFM bit set).
Figure 11-1 through Figure 11-2 show the A/D result
data format of the PIC16C717/770/771.
FIGURE 11-1: PIC16C770/771 12-BIT A/D RESULT FORMATS
ADRESH (1Eh)
ADRESL (9Eh)
LSB
Left Justified
MSB
(ADFM = 0)
bit7
bit7
12-bit A/D Result
Unused
Right Justified
(ADFM = 1)
MSB
LSB
bit7
bit7
Unused
12-bit A/D Result
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 115
PIC16C717/770/771
FIGURE 11-2: PIC16C717 10-BIT A/D RESULT FORMAT
(ADFM = 0)
MSB
bit7
LSB
bit7
bit7
10-bit A/D Result
MSB
Unused
(ADFM = 1)
LSB
bit7
Unused
Unused
10-bit A/D Result
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 and ANSEL bits
selected as an input. To determine acquisition time, see
Section 11.6. After this acquisition time has elapsed,
the A/D conversion can be started. The following steps
should be followed for doing an A/D conversion:
11.2.2 CONFIGURING THE REFERENCE
VOLTAGES
The VCFG bits in the ADCON1 register configure the
A/D module reference inputs. The reference high
input can come from an internal reference (VRH) or
(VRL), an external reference (VREF+), or AVDD. The
low reference input can come from an internal refer-
ence (VRL), an external reference (VREF-), or AVSS. If
an external reference is chosen for the reference high
or reference low inputs, the port pin that multiplexes
the incoming external references is configured as an
analog input, regardless of the values contained in the
A/D port configuration bits (PCFG<3:0>).
11.2
Configuring the A/D Module
11.2.1 CONFIGURING ANALOG PORT PINS
The ANSEL and TRIS registers control the operation
of the A/D port pins. The port pins that are desired as
analog inputs must have their corresponding TRIS bit
set (input). If the TRIS bit is cleared (output), the digital
output level (VOH or VOL) will be converted. The proper
ANSEL bits must be set (analog input) to disable the
digital input buffer.
The A/D operation is independent of the state of the
TRIS bits and the ANSEL bits.
Note 1: When reading the PORTA or PORTB reg-
ister, all pins configured as analog input
channels will read as ’0’.
2: Analog levels on any pin that is defined as
a digital input, including the ANx pins, may
cause the input buffer to consume current
that is out of the devices specification.
DS41120A-page 116
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
After the A/D module has been configured as desired
and the analog input channels have their correspond-
ing TRIS bits selected for port inputs, the selected
channel must be acquired before conversion is
started. The A/D conversion cycle can be initiated by
setting the GO/DONE bit. The A/D conversion begins
and lasts for 13TAD. The following steps should be fol-
lowed for performing an A/D conversion:
4. Wait the required acquisition time (3TAD)
5. Start conversion
• Set GO/DONE bit (ADCON0)
6. Wait 13TAD until A/D conversion is complete, by
either:
• Polling for the GO/DONE bit to be cleared
OR
1. Configure port pins:
• Waiting for the A/D interrupt
• Configure analog input mode (ANSEL)
• Configure pin as input (TRISA or TRISB)
2. Configure the A/D module
7. Read A/D Result registers (ADRESH and
ADRESL), clear ADIF if required.
8. For next conversion, go to step 1, step 2 or step
3 as required.
• Configure A/D Result Format / voltage refer-
ence (ADCON1)
Clearing the GO/DONE bit during a conversion will
abort the current conversion. The ADRESH and
ADRESL registers will be updated with the partially
completed A/D conversion value. That is, the ADRESH
and ADRESL registers will contain the value of the
current incomplete conversion.
• Select A/D input channel (ADCON0)
• Select A/D conversion clock (ADCON0)
• Turn on A/D module (ADCON0)
3. Configure A/D interrupt (if required)
• Clear ADIF bit
Note: Do not set the ADON bit and the GO/
DONE bit in the same instruction. Doing so
will cause the GO/DONE bit to be automat-
ically cleared.
• Set ADIE bit
• Set PEIE bit
• Set GIE bit
FIGURE 11-3: A/D BLOCK DIAGRAM
CHS<3:0>
VAIN
RB1/AN5/SS
(Input voltage)
RB0/AN4/INT
RA3/AN3/VREF+/VRH
RA2/AN2/VREF-/VRL
RA1/AN1
AVDD
RA0/AN0
VREF+
VRH
VRL
(Reference
voltage +)
VCFG<2:0>
A/D
Converter
VREF-
VRL
(Reference
voltage -)
AVSS
VCFG<2:0>
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 117
PIC16C717/770/771
If the VRH or VRL are used for the A/D converter refer-
ence, then the TAD requirement is automatically
increased by a factor of 8.
11.3
Selecting the A/D Conversion Clock
The A/D conversion cycle requires 13TAD: 1 TAD for set-
tling time, and 12 TAD for conversion. The source of the
A/D conversion clock is software selected. If neither the
internal VRH nor VRL are used for the A/D converter,
the four possible options for TAD are:
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 11-1 shows the resultant TAD times
derived from the device operating frequencies and the
A/D clock source selected.
• 2 TOSC
• 8 TOSC
The ADIF bit is set on the rising edge of the 14th TAD.
The GO/DONE bit is cleared on the falling edge of the
14th TAD.
• 32 TOSC
• A/D RC oscillator
TABLE 11-1: TAD vs. DEVICE OPERATING FREQUENCIES
A/D Reference
A/D Clock Source (TAD)
Source
Device Frequency
Operation
2 TOSC
ADCS<1:0>
20 MHz
100 ns(2)
800 ns(2)
1.6 µs
2 - 6 µs(1,4)
800 ns(2)
6.4 µs(2)
5 MHz
4 MHz
500 ns(2)
2.0 µs
8.0 µs(3)
2 - 6 µs(1,4)
4 µs(2)
1.25 MHz
1.6 µs
00
01
10
11
00
01
10
11
400 ns(2)
ExternalVREF or
Analog Supply
8 TOSC
1.6 µs
6.4 µs
24 µs(3)
2 - 6 µs(1,4)
32 TOSC
A/D RC
6.4 µs
2 - 6 µs(1,4)
3.2 µs(2)
12.8 µs
Internal VRH or 16 TOSC
12.8 µs
VRL
64 TOSC
16 µs
64 µs(3)
16 - 48 µs(4,5)
51.2 µs
256 TOSC
12.8 µs
16 - 48 µs(4,5)
51.2 µs
16 - 48 µs(4,5)
192 µs(3)
16 - 48 µs(4,5)
A/D RC
Legend: Shaded cells are outside of recommended range.
Note 1: The A/D RC source has a typical TAD time of 4 µs for VDD > 3.0V.
2: These values violate the minimum required TAD time.
3: For faster conversion times, the selection of another clock source is recommended.
4: When the device frequency is greater than 1 MHz, the A/D RC clock source is only recommended if the conversion will be
performed during sleep.
5: The resource has a typical TAD time of 32 µs for VDD > 3.0V.
DS41120A-page 118
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
11.4
A/D Conversions
Example 11-1 shows an example that performs an A/D
conversion. The port pins are configured as analog
inputs. The analog reference VREF+ is the device AVDD
and the analog reference VREF- is the device AVSS. The
A/D interrupt is enabled and the A/D conversion clock
is TRC. The conversion is performed on the AN0
channel.
EXAMPLE 11-1: PERFORMING AN A/D CONVERSION
BCF
BSF
CLRF
PIR1, ADIF
STATUS, RP0
ADCON1
;Clear A/D Int Flag
;Select Bank 1
;Configure A/D Voltage Reference
MOVLW 0x01
MOVWF ANSEL
MOVWF TRISA
;disable AN0 digital input buffer
;RA0 is input mode
;Enable A/D interrupt
;Select Bank 0
BSF
BCF
PIE1, ADIE
STATUS, RP0
MOVLW 0xC1
;RC clock, A/D is on,
;Ch 0 is selected
;
MOVWF ADCON0
BSF
BSF
INTCON, PEIE
INTCON, GIE
;Enable Peripheral
;Enable All Interrupts
;
; Ensure that the required sampling time for the
; selected input channel has lapsed. Then the
; conversion may be started.
BSF
ADCON0, GO
:
;Start A/D Conversion
;The ADIF bit will be
;set and the GO/DONE bit
;cleared upon completion-
;of the A/D conversion.
:
; Wait for A/D completion and read ADRESH:ADRESL for result.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 119
PIC16C717/770/771
11.5
A/D Converter Module Operation
Figure 11-4 shows the flowchart of the A/D converter
module.
FIGURE 11-4: FLOWCHART OF A/D OPERATION
ADON = 0
Yes
ADON = 0?
No
Sample
Selected Channel
Yes
GO = 0?
No
Yes
Yes
Start of A/D
Conversion Delayed
1 Instruction Cycle
Finish Conversion
GO = 0
SLEEP
A/D Clock
= RC?
Instruction?
ADIF = 1
No
No
Yes
From Sleep?
Yes
Instruction?
Wake-up
Abort Conversion
GO = 0
Finish Conversion
GO = 0
SLEEP
Wait 2 Tad
ADIF = 0
ADIF = 1
No
No
SLEEP
Power down A/D
Finish Conversion
GO = 0
Stay in Sleep
Powerdown A/D
Wait 2 Tad
ADIF = 1
Wait 2 Tad
DS41120A-page 120
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
source impedance (RS) and the internal sampling
switch (RSS) impedance directly affect the time
required to charge the capacitor CHOLD. The sampling
switch (RSS) impedance varies over the device voltage
(VDD), see Figure 11-5. The maximum recom-
mended impedance for analog sources is 2.5 kΩ .
After the analog input channel is selected (changed)
this sampling must be done before the conversion can
be started.
11.6
A/D Sample Requirements
11.6.1 RECOMMENDED SOURCE IMPEDANCE
The maximum recommended impedance for ana-
log sources is 2.5 kΩ. This value is calculated based
on the maximum leakage current of the input pin. The
leakage current is 100 nA max., and the analog input
voltage cannot be varied by more than 1/4 LSb or
250 µV due to leakage. This places a requirement on
the input impedance of 250 µV/100 nA = 2.5 kΩ.
To calculate the minimum sampling time, Equation 11-
2 may be used. This equation assumes that 1/4 LSb
error is used (16384 steps for the A/D). The 1/4 LSb
error is the maximum error allowed for the A/D to meet
its specified resolution.
11.6.2 SAMPLING TIME CALCULATION
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 11-5. The
The CHOLD is assumed to be 25 pF for the 12-bit
A/D.
EXAMPLE 11-2: A/D SAMPLING TIME EQUATION
(-T /C (RIC +RSS + RS)
(-T /C (RIC +RSS + RS)
C
C
VHOLD =(VREF - VREF/16384) = (VREF) • (1 -e
) VREF(1 - 1/16384) = VREF • (1 -e
)
Tc = -CHOLD (1kΩ + RSS + RS) In (1/16384)
Figure 11-3 shows the calculation of the minimum time
required to charge CHOLD. This calculation is based on
the following system assumptions:
CHOLD = 25 pF
RS = 2.5 kΩ
1/4 LSb error
VDD = 5V → RSS = 10 kΩ (worst case)
Temp (system Max.) = 50°C
Note 1:The reference voltage (VREF) has no
effect on the equation, since it cancels
itself out.
2:The charge holding capacitor (CHOLD) is
not discharged after each conversion.
3:The maximum recommended impedance
for analog sources is 2.5 kΩ . This is
required to meet the pin leakage specifi-
cation.
4:After a conversion has completed, you
must wait 2 TAD time before sampling can
begin again. During this time, the holding
capacitor is not connected to the selected
A/D input channel.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 121
PIC16C717/770/771
EXAMPLE 11-3: CALCULATING THE MINIMUM
REQUIRED SAMPLE TIME
TACQ =
Amplifier Settling Time
+ Holding Capacitor Charging Time
+Temperature offset
†
TACQ =
5 µs
+ TC
+ [(Temp - 25°C)(0.05 µs/°C)] †
TC = Holding Capacitor Charging Time
TC = (CHOLD) (RIC + RSS + RS) In (1/16384)
TC = -25 pF (1 kΩ +10 kΩ + 2.5 kΩ) In (1/16384)
TC = -25 pF (13.5 kΩ) In (1/16384)
TC = -0.338 (-9.704)µs
TC = 3.3µs
TACQ =
5 µs
+ 3.3 µs
+ [(50°C - 25°C)(0.05 µs / °C)]
TACQ =
TACQ =
8.3 µs + 1.25 µs
9.55 µs
† The temperature coefficient is only required for
temperatures > 25°C.
FIGURE 11-5: ANALOG INPUT MODEL
VDD
Sampling
Switch
VT = 0.6V
VT = 0.6V
Port Pin
Rs
SS
RIC 1k
RSS
CPIN
5 pF
VA
ILEAKAGE
± 100 nA
CHOLD = 25 pF
VSS
Legend CPIN
VT
= input capacitance
= threshold voltage
6V
5V
ILEAKAGE = leakage current at the pin due to
VDD 4V
3V
various junctions
2V
RIC
SS
= interconnect resistance
= sampling switch
CHOLD
= sample/hold capacitance (from DAC)
5 6 7 8 9 10 11
Sampling Switch (RSS)
( kΩ )
DS41120A-page 122
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
11.7
Use of the ECCP1 Trigger
11.9
Faster Conversion - Lower
Resolution Trade-off
An A/D conversion can be started by the “special event
trigger” of the CCP module. This requires that the
CCP1M<3:0> bits be programmed as 1011band that
the A/D module is enabled (ADON is set). When the
trigger occurs, the GO/DONE bit will be set on Q2 to
start the A/D conversion and the Timer1 counter will
be reset to zero. Timer1 is reset to automatically
repeat the A/D conversion cycle, with minimal software
overhead (moving the ADRESH and ADRESL to the
desired location). The appropriate analog input chan-
nel must be selected before the “special event trigger”
sets the GO/DONE bit (starts a conversion cycle).
Not all applications require a result with 12-bits of res-
olution, 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 resolution required, the acquisition time is the
same. To speed up the conversion, the A/D module
may be halted by clearing the GO/DONE bit after the
desired number of bits in the result have been con-
verted. Once the GO/DONE bit has been cleared, all
of the remaining A/D result bits are ‘0’. The equation
to determine the time before the GO/DONE bit can be
switched is as follows:
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.
Conversion time = (N+1)TAD
Where: N = number of bits of resolution required,
and 1TAD is the amplifier settling time.
11.8
Effects of a RESET
Since TAD is based from the device oscillator, the user
must use some method (a timer, software loop, etc.) to
determine when the A/D GO/DONE bit may be
cleared. Table 11-4 shows a comparison of time
required for a conversion with 4-bits of resolution, ver-
sus the normal 12-bit resolution conversion. The
example is for devices operating at 20 MHz. The A/D
clock is programmed for 32 TOSC.
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
ADRESH and ADRESL registers are not modified.
The ADRESH and ADRESL registers will contain
unknown data after a Power-on Reset.
EXAMPLE 11-4: 4-BIT vs. 12-BIT
CONVERSION TIME
EXAMPLE
4 Bit Example:
Conversion Time = (N + 1) TAD
= (4 + 1) TAD
= (5)(1.6 µS)
= 8 µS
12 Bit Example:
Conversion Time = (N + 1) TAD
= (12 + 1) TAD
= (13)(1.6 µS)
= 20.8 µS
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 123
PIC16C717/770/771
Turning off the A/D places the A/D module in its lowest
current consumption state.
11.10 A/D Operation During Sleep
The A/D module can operate during SLEEP mode. This
requires that the A/D clock source be configured for RC
(ADCS<1:0> = 11b). With the RC clock source
selected, when the GO/DONE bit is set the A/D module
waits one instruction cycle before starting the conver-
sion cycle. This allows the SLEEPinstruction to be exe-
cuted, which eliminates all digital switching noise
during the sample and conversion. When the conver-
sion cycle is completed the GO/DONE bit is cleared,
and the result loaded into the ADRESH and ADRESL
registers. 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 module will then be turned off,
although the ADON bit will remain set.
Note: For the A/D module to operate in SLEEP,
the A/D clock source must be configured to
RC (ADCS<1:0> = 11b).
11.11 Connection Considerations
Since the analog inputs employ ESD protection, they
have diodes to VDD and VSS. This requires that the
analog input must be between VDD and VSS. If the input
voltage exceeds this range by greater than 0.3V (either
direction), one of the diodes becomes forward biased
and it may damage the device if the input current spec-
ification is exceeded.
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 2.5 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.
When the A/D clock source is another clock option (not
RC), a SLEEP instruction causes the present conver-
sion to be aborted and the A/D module is turned off,
though the ADON bit will remain set.
TABLE 11-2: SUMMARY OF A/D REGISTERS
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
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000u
PIR1
ADIF
ADIE
SSPIF
SSPIE
CCP1IF
CCP1IE
TMR2IF TMR1IF -0-- 0000 -0-- 0000
TMR2IE TMR1IE -0-- 0000 -0-- 0000
—
—
—
—
—
—
0Ch
PIE1
8Ch
1Eh
9Eh
9Bh
1Fh
9Fh
05h
06h
85h
86h
9Dh
ADRESH A/D High Byte Result Register
ADRESL A/D Low Byte Result Register
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
REFCON VRHEN VRLEN VRHOEN VRLOEN
—
—
—
CHS3
—
—
ADON
—
0000 ----
0000 0000 0000 0000
0000 ---- 0000 ----
0000 ----
ADCON0 ADCS1 ADCS0
CHS2
CHS1
CHS0 GO/DONE
ADCON1
PORTA
PORTB
TRISA
ADFM
VCFG2
VCFG1
VCFG0
—
—
PORTA Data Latch when written: PORTA pins when read
PORTB Data Latch when written: PORTB pins when read
PORTA Data Direction Register
000x 0000 000u 0000
xxxx xx00 uuuu uu00
1111 1111 1111 1111
1111 1111 1111 1111
1111 1111 1111 1111
TRISB
PORTB Data Direction Register
ANSEL
ANS5
ANS4
ANS3
ANS2
ANS1
ANS0
Legend: x= unknown, u= unchanged, -= unimplemented read as ’0’. Shaded cells are not used for A/D conversion.
DS41120A-page 124
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Some of the core features provided may not be neces-
sary to each application that a device may be used for.
The configuration word bits allow these features to be
configured/enabled/disabled as necessary. These fea-
tures include code protection, brown-out reset and its
trippoint, the power-up timer, the watchdog timer and
the devices oscillator mode. As can be seen in
Figure 12-1, some additional configuration word bits
have been provided for brown-out reset trippoint selec-
tion.
12.0 SPECIAL FEATURES OF THE
CPU
These devices have a host of features intended to
maximize system reliability, minimize cost through elim-
ination of external components, provide power saving
operating modes and offer code protection. These are:
• Oscillator Selection
• Reset
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
• Watchdog Timer (WDT)
• Low-voltage detection
• SLEEP
• Code protection
• ID locations
• In-circuit serial programming (ICSP)
These devices have 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
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 type resets
only (POR, BOR), designed to keep the part in reset
while the power supply stabilizes. With these two timers
on-chip, most applications need no external reset cir-
cuitry.
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 INTRC and ER oscillator options save system cost
while the LP crystal option saves power. A set of con-
figuration bits are used to select various options.
Additional information on special features is available in
the PICmicro™ Mid-Range Reference Manual,
(DS33023).
12.1
Configuration Bits
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.
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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 125
PIC16C717/770/771
FIGURE 12-1: CONFIGURATION WORD FOR 16C717/770/771 DEVICE
CP
CP BORV1 BORV0 CP
11 10
CP
8
—
BODEN MCLRE PWRTE WDTE FOSC2 FOSC1 FOSC0
Register: CONFIG
Address 2007h
bit13 12
9
7
6
5
4
3
2
1
bit0
bit 13,12: CP: Program Memory Code Protection
bit 9,8: 1= Code protection off
(2)
0= All program memory is protected
bit 11-10: BORV<1:0>: Brown-out Reset Voltage bits
00= VBOR set to 4.5V
01= VBOR set to 4.2V
10= VBOR set to 2.7V
11= VBOR set to 2.5V
bit 7:
bit 6:
Unimplemented: Read as ’1’
(1)
BODEN: Brown-out Detect Reset Enable bit
1= Brown-out Detect Reset enabled
0= Brown-out Detect Reset disabled
bit 5:
bit 4:
bit 3:
MCLRE: RA5/MCLR pin function select
1= RA5/MCLR pin function is MCLR
0= RA5/MCLR pin function is digital input, MCLR internally tied to VDD
(1)
PWRTE: Power-up Timer Enable bit
1= PWRT disabled
0= PWRT enabled
WDTE: Watchdog Timer Enable bit
1= WDT enabled
0= WDT disabled
bit 2-0: FOSC<2:0>: Oscillator Selection bits
000= LP oscillator: Ceramic resonator on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN
001= XT oscillator: Crystal on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN
010= HS oscillator: High frequency crystal on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN
011= EC: I/O function on RA6/OSC2/CLKOUT pin, CLKIN function on RA7/OSC1/CLKIN
100= INTRC oscillator: I/O function on RA6/OSC2/CLKOUT pin, I/O function on RA7/OSC1/CLKIN
101= INTRC oscillator: CLKOUT function on RA6/OSC2/CLKOUT pin, I/O function on RA7/OSC1/CLKIN
110= ER oscillator: I/O function on RA6/OSC2/CLKOUT pin, Resistor on RA7/OSC1/CLKIN
111= ER oscillator: CLKOUT function on RA6/OSC2/CLKOUT pin, Resistor on RA7/OSC1/CLKIN
Note 1: Enabling Brown-out Reset automatically enables the 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 CP bits must be given the same value to enable code protection.
12.2.2 LP, XT AND HS MODES
12.2
Oscillator Configurations
In LP, XT or HS modes, a crystal or ceramic resonator
is connected to the OSC1/CLKIN and OSC2/CLKOUT
pins to establish oscillation (Figure 12-2). The
PIC16C717/770/771 oscillator design requires the use
of a parallel cut crystal. Use of a series cut crystal may
give a frequency out of the crystal manufacturers spec-
ifications.
12.2.1
OSCILLATOR TYPES
The PIC16C717/770/771 can be operated in four differ-
ent oscillator modes. The user can program three con-
figuration bits (FOSC<2:0>) to select one of these eight
modes:
• LP
• XT
• HS
• ER
Low Power Crystal
Crystal/Resonator
High Speed Crystal/Resonator
External Resistor (with and without
CLKOUT)
• INTRC Internal 4 MHz (with and without
CLKOUT)
• EC
External Clock
DS41120A-page 126
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
12.2.3 EC MODE
FIGURE 12-2: CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS, XT OR LP
In applications where the clock source is external, the
PIC16C717/770/771 should be programmed to select
the EC (External Clock) mode. In this mode, the RA6/
OSC2/CLKOUT pin is available as an I/O pin. See
Figure 12-3 for illustration.
OSC CONFIGURATION)
C1(1)
OSC1
To
internal
logic
FIGURE 12-3: EXTERNAL CLOCK INPUT
OPERATION (EC OSC
XTAL
RS(2)
RF(3)
OSC2
SLEEP
PIC16C717/770/771
CONFIGURATION)
C2(1)
OSC1
PIC16C717/770/771
Clock from
ext. system
Note1: See Table 12-1 and Table 12-2 for recom-
mended values of C1 and C2.
RA6
I/O
2: A series resistor (RS) may be required for
AT strip cut crystals.
3: RF varies with the crystal chosen.
TABLE 12-1: CERAMIC RESONATORS
Ranges Tested:
Mode
XT
Freq
OSC1
OSC2
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
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.
All resonators used did not have built-in capacitors.
TABLE 12-2: 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
XT
HS
47-68 pF
15 pF
47-68 pF
15 pF
4 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
These values are for design guidance only. See
notes at bottom of page.
Note 1: Since each resonator/crystal has its own
characteristics, the user should consult the
resonator/crystal manufacturer for appropri-
ate values of external components.
2: Higher capacitance increases the stability
of oscillator but also increases the start-up
time.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 127
PIC16C717/770/771
12.2.4 ER MODE
12.2.6 CLKOUT
For timing insensitive applications, the ER (External
Resistor) clock mode offers additional cost savings.
Only one external component, a resistor connected to
the OSC1 pin and VSS, is needed to set the operating
frequency of the internal oscillator. The resistor draws
a DC bias current which controls the oscillation fre-
quency. In addition to the resistance value, the oscilla-
tor frequency will vary from unit to unit, and as a
function of supply voltage and temperature. Since the
controlling parameter is a DC current and not a capac-
itance, the particular package type and lead frame will
not have a significant effect on the resultant frequency.
In the INTRC and ER modes, the PIC16C717/770/771
can be configured to provide a clock out signal by pro-
gramming the configuration word. The oscillator fre-
quency, divided by 4, can be used for test purposes or
to synchronize other logic.
In the INTRC and ER modes, if the CLKOUT output is
enabled, CLKOUT is held low during reset.
12.2.7 DUAL SPEED OPERATION FOR ER AND
INTRC MODES
A software programmable dual speed oscillator is avail-
able in either ER or INTRC oscillator modes. This fea-
ture allows the applications to dynamically toggle the
oscillator speed between normal and slow frequencies.
The nominal slow frequency is 37KHz. In ER mode, the
slow speed operation is fixed and does not vary with
resistor size. Applications that require low current
power savings, but cannot tolerate putting the part into
sleep, may use this mode.
Figure 12-4 shows how the controlling resistor is con-
nected to the PIC16C717/770/771. For Rext values
below 38k ohms, the oscillator operation may become
unstable, or stop completely. For very high Rext values
(e.g. 1M), the oscillator becomes sensitive to noise,
humidity and leakage. Thus, we recommend keeping
Rext between 38k and 1M ohms.
The OSCF bit in the PCON register is used to control
FIGURE 12-4: EXTERNAL RESISTOR
dual speed mode.
See the PCON Register,
Register 2-8, for details.
PIC16C717/770/771
When changing the INTRC or ER internal oscillator
speed, there is a period of time when the processor is
inactive. When the speed changes from fast to slow, the
processor inactive period is in the range of 100 µS to
300 µS. For speed change from slow to fast, the pro-
cessor is in active for 1.25 µS to 3.25 µS.
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
REXT
The Electrical Specification section shows the relation-
ship between the Rext resistance value and the operat-
ing frequency as well as frequency variations due to
operating temperature for given Rext and VDD values.
The ER oscillator mode has two options that control the
OSC2 pin. The first allows it to be used as a general
purpose I/O port. The other configures the pin as CLK-
OUT. The ER oscillator does not run during reset.
12.2.5 INTRC MODE
The internal RC oscillator provides a fixed 4 MHz (nom-
inal) system clock at VDD = 5V and 25°C, see “Electrical
Specifications” section for information on variation over
voltage and temperature. The INTRC oscillator does
not run during reset.
DS41120A-page 128
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Some registers are not affected in any reset condition.
Their status is unknown on a power-up reset and
unchanged in any other reset. Most other registers are
placed into an initialized state upon reset, however they
are not affected by a WDT reset during sleep, because
this is considered a WDT Wakeup, which is viewed as
the resumption of normal operation.
12.3
Reset
The PIC16C717/770/771 devices have several differ-
ent resets. These resets are grouped into two classifi-
cations; power-up and non-power-up. The power-up
type resets are the power-on and brown-out resets
which assume the device VDD was below its normal
operating range for the device’s configuration. The non-
power up type resets assume normal operating limits
were maintained before/during and after the reset.
Several status bits have been provided to indicate
which reset occurred (see Table 12-4). See Table 12-6
for a full description of reset states of all registers.
• Power-on Reset (POR)
A simplified block diagram of the on-chip reset circuit is
shown in Figure 12-5.
• Programmable Brown-out Reset (PBOR)
• MCLR reset during normal operation
• MCLR reset during SLEEP
These devices have a MCLR noise filter in the MCLR
reset path. The filter will detect and ignore small pulses.
• WDT Reset (during normal operation)
It should be noted that a WDT Reset does not drive
MCLR pin low.
FIGURE 12-5: SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
External
Reset
MCLR
SLEEP
Time-out
WDT
Module
VDD rise
detect
Power-on Reset
VDD
Programmable
Brown-out
S
R
BODEN
OST/PWRT
OST
Chip_Reset
Q
10-bit Ripple counter
OSC1
PWRT
10-bit Ripple counter
Dedicated
Oscillator
Enable PWRT
Enable OST
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 129
PIC16C717/770/771
12.4
Power-On Reset (POR)
12.5
Power-up Timer (PWRT)
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 enable the internal
MCLR feature. This will eliminate external RC compo-
nents usually needed to create a Power-on Reset. A
maximum rise time for VDD is specified. See Electrical
Specifications for details. For a slow rise time, see
Figure 12-6.
The Power-up Timer provides a fixed TPWRT time-out
on power-up type resets only. For a POR, the PWRT is
invoked when the POR pulse is generated. For a BOR,
the PWRT is invoked when the device exits the reset
condition (VDD rises above BOR trippoint). 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 is designed to allow VDD to rise to
an acceptable level. A configuration bit is provided to
enable/disable the PWRT for the POR only. For a BOR
the PWRT is always available regardless of the config-
uration bit setting.
Two delay timers, (PWRT on OST), have been pro-
vided which hold the device in reset after a POR
(dependent upon device configuration) so that all oper-
ational parameters have been met prior to releasing the
device to resume/begin normal operation.
The power-up time delay will vary from chip-to-chip due
to VDD, temperature and process variation. See DC
parameters for details.
When the device starts normal operation (exits the
reset condition), device operating parameters (voltage,
frequency, temperature,...) must be met to ensure oper-
ation. 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 con-
ditions, or if necessary an external POR circuit may be
implemented to delay end of reset for as long as
needed.
12.6
Oscillator Start-up Timer (OST)
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.
The OST time-out is invoked only for XT, LP and HS
modes and only on a power-up type reset or a wake-up
from SLEEP.
FIGURE 12-6: EXTERNAL POWER-ON
RESET CIRCUIT (FOR SLOW
VDD RAMP)
12.7
Programmable Brown-Out Reset
(PBOR)
VDD
VDD
The Programmable Brown-out Reset module is used to
generate a reset when the supply voltage falls below a
specified trip voltage. The trip voltage is configurable to
any one of four voltages provided by the BORV<1:0>
configuration word bits.
D
R
R1
MCLR
PIC16C717/770/771
C
Configuration bit, BODEN, can disable (if clear/pro-
grammed) or enable (if set) the Brown-out Reset cir-
cuitry. If VDD falls below the specified trippoint for longer
than TBOR, (parameter #35), the brown-out situation
will reset the chip. A reset may not occur if VDD falls
below the trippoint for less than TBOR. The chip will
remain in Brown-out Reset until VDD rises above VBOR.
The Power-up Timer will be invoked at that point and
will keep the chip in RESET an additional TPWRT. If VDD
drops below VBOR while the Power-up Timer is running,
the chip will go back into a Brown-out Reset and the
Power-up Timer will be re-initialized. Once VDD rises
above VBOR, the Power-up Timer will again begin a
TPWRT time delay. Even though the PWRT is always
enabled when brown-out is enabled, the PWRT config-
uration word bit should be cleared (enabled) when
brown-out is enabled.
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: R < 40 kΩ is recommended to make sure
that voltage drop across R does not violate
the device’s electrical specification.
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).
DS41120A-page 130
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Table 12-5 shows the reset conditions for some special
function registers, while Table 12-6 shows the reset
conditions for all the registers.
12.8
Time-out Sequence
On power-up, the time-out sequence is as follows: First
PWRT time-out is invoked by the POR pulse. When the
PWRT delay expires, the Oscillator Start-up Timer is
activated. The total time-out will vary based on oscilla-
tor 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 12-7, Figure 12-8,
Figure 12-9 and Figure 12-10 depict time-out
sequences on power-up.
12.9
Power Control/Status Register
(PCON)
The Power Control/Status Register, PCON, has two
status bits that provide indication of which power-up
type reset occurred.
Bit0 is Brown-out Reset Status bit, BOR. Bit BOR is set
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. However, if the
brown-out circuitry is disabled, the BOR bit is a "Don’t
Care" bit and is considered unknown upon a POR.
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 12-9). This is useful for testing purposes or to
synchronize more than one PICmicro microcontroller
operating 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 12-3: TIME-OUT IN VARIOUS SITUATIONS
Power-up
Wake-up from
Oscillator Configuration
Brown-out
SLEEP
PWRTE = 0
TPWRT + 1024TOSC
TPWRT
PWRTE = 1
XT, HS, LP
1024TOSC
TPWRT + 1024TOSC
TPWRT
1024TOSC
EC, ER, INTRC
—
—
TABLE 12-4: STATUS BITS AND THEIR SIGNIFICANCE
POR
BOR
TO
PD
0
0
0
1
1
1
1
1
1
x
x
0
1
1
1
1
1
0
x
1
0
0
u
1
1
x
0
1
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 12-5: RESET CONDITION FOR SPECIAL REGISTERS
Program
Counter
STATUS
Register
PCON
Register
Condition
Power-on Reset
000h
000h
0001 1xxx
000u uuuu
0001 0uuu
0000 1uuu
uuu0 0uuu
0001 1uuu
uuu1 0uuu
uuu1 0uuu
---- 1-01
---- 1-uu
---- 1-uu
---- 1-uu
---- u-uu
---- 1-u0
---- u-uu
---- u-uu
MCLR Reset during normal operation
MCLR Reset during SLEEP
WDT Reset
000h
000h
WDT Wake-up
PC + 1
000h
Brown-out Reset
Interrupt wake-up from SLEEP, GIE = 0
Interrupt wake-up from SLEEP, GIE = 1
PC + 1
0004h
Legend: u= unchanged, x= unknown, -= unimplemented bit read as '0'.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 131
PIC16C717/770/771
TABLE 12-6: INITIALIZATION CONDITIONS FOR ALL REGISTERS
Register
Power-on Reset or
Brown-out Reset
MCLR Reset or
WDT Reset
Wake-up via WDT or
Interrupt
W
xxxx xxxx
0000 0000
xxxx xxxx
0000h
uuuu uuuu
uuuu uuuu
uuuu uuuu
0000h
uuuu uuuu
uuuu uuuu
uuuu uuuu
INDF
TMR0
PCL
PC + 1(1)
000q quuu(2)
uuuu uuuu
uuuu 0000
uuuu uu00
---0 0000
0000 000u
uuuq quuu(2)
uuuu uuuu
uuuu uuuu
uuuu uu00
---u uuuu
STATUS
0001 1xxx
FSR
xxxx xxxx
xxxx 0000
xxxx xx00
---0 0000
0000 000x
PORTA
PORTB
PCLATH
INTCON
uuuu uuqq
PIR1
-0-- 0000
-0-- 0000
-0-- uuuu
q--- q---
uuuu uuuu
uuuu uuuu
--uu uuuu
uuuu uuuu
-uuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
-u-- uuuu
u--- u---
---- u-uu
1111 1111
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu ----
PIR2
0--- 0---
xxxx xxxx
xxxx xxxx
--00 0000
0000 0000
-000 0000
xxxx xxxx
0000 0000
xxxx xxxx
xxxx xxxx
0000 0000
xxxx xxxx
0000 0000
1111 1111
1111 1111
1111 1111
-0-- 0000
0--- 0---
---- 1-qq
1111 1111
0000 0000
0000 0000
1111 1111
1111 0000
0000 0000
0000 ----
0--- 0---
uuuu uuuu
uuuu uuuu
--uu uuuu
0000 0000
-000 0000
uuuu uuuu
0000 0000
uuuu uuuu
uuuu uuuu
0000 0000
uuuu uuuu
0000 0000
1111 1111
1111 1111
1111 1111
-0-- 0000
0--- 0---
---- 1-uu
1111 1111
0000 0000
0000 0000
1111 1111
1111 0000
0000 0000
0000 ----
TMR1L
TMR1H
T1CON
TMR2
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON
ADRESH
ADCON0
OPTION_REG
TRISA
TRISB
PIE1
PIE2
PCON
PR2
SSPADD
SSPSTAT
WPUB
IOCB
P1DEL
REFCON
Legend: u = unchanged,
x
= unknown, -= unimplemented bit, read as ’0’, q= value
depends on condition
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).
2: See Table 12-5 for reset value for specific condition.
DS41120A-page 132
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 12-6: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register
Power-on Reset or
Brown-out Reset
MCLR Reset or
WDT Reset
Wake-up via WDT or
Interrupt
LVDCON
ANSEL
--00 0101
1111 1111
xxxx xxxx
0000 000
--00 0101
1111 1111
uuuu uuuu
0000 0000
uuuu uuuu
uuuu uuuu
--uu uuuu
---- uuuu
1--- ---0
--uu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu
--uu uuuu
---- uuuu
1--- ---0
ADRESL
ADCON1
PMDATL
PMADRL
PMDATH
PMADRH
PMCON1
xxxx xxxx
xxxx xxxx
--xx xxxx
---- xxxx
1--- ---0
Legend: u = unchanged,
x = unknown, -= unimplemented bit, read as ’0’, q= value
depends on condition
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).
2: See Table 12-5 for reset value for specific condition.
FIGURE 12-7: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD)
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 133
PIC16C717/770/771
FIGURE 12-8: 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 12-9: 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 12-10: SLOW VDD RISE TIME (MCLR TIED TO VDD)
5V
0V
VDD
MCLR
INTERNAL POR
TPWRT
(1)
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
Note 1: Time dependent on oscillator circuit
DS41120A-page 134
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
The RB0/INT pin interrupt, the RB port change interrupt
and the TMR0 overflow interrupt flags are contained in
the INTCON register.
12.10 Interrupts
The devices have up to 11 sources of interrupt. The
interrupt control register (INTCON) records individual
interrupt requests in flag bits. It also has individual and
global interrupt enable bits.
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.
Note: Individual interrupt flag bits are set regard-
less of the status of their corresponding
mask bit or the GIE bit.
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.
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. The latency
is the same for one or two cycle instructions. Individual
interrupt flag bits are set regardless of the status of
their corresponding mask bit or the GIE bit
The “return from interrupt” instruction, RETFIE, exits
the interrupt routine as well as sets the GIE bit, which
re-enables interrupts.
FIGURE 12-11: INTERRUPT LOGIC
LVDIF
LVDIE
Wake-up (If in SLEEP mode)
ADIF
ADIE
T0IF
T0IE
INTF
INTE
Interrupt to CPU
RBIF
RBIE
SSPIF
SSPIE
CCP1IF
CCP1IE
PEIE
GIE
TMR2IF
TMR2IE
TMR1IF
TMR1IE
BCLIF
BCLIE
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 135
PIC16C717/770/771
12.10.1 INT INTERRUPT
12.11 Context Saving During Interrupts
External interrupt on RB0/INT pin is edge triggered:
either rising if bit INTEDG (OPTION_REG<6>) is set,
or falling, 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 12.13 for details on SLEEP mode.
During an interrupt, only the PC is saved on the stack.
At the very least, W and STATUS should be saved to
preserve the context for the interrupted program. All
registers that may be corrupted by the ISR, such as
PCLATH or FSR, should be saved.
Example 12-1 stores and restores the STATUS, W and
PCLATH registers. The register, W_TEMP, is defined in
Common RAM, the last 16 bytes of each bank that may
be accessed from any bank. The STATUS_TEMP and
PCLATH_TEMP are defined in bank 0.
The example:
a) Stores the W register.
b) Stores the STATUS register in bank 0.
c) Stores the PCLATH register in bank 0.
d) Executes the ISR code.
12.10.2 TMR0 INTERRUPT
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 2.2.2.3)
e) Restores the PCLATH register.
f) Restores the STATUS register
g) Restores W.
12.10.3 PORTB INTCON CHANGE
Note
that
W_TEMP,
STATUS_TEMP
and
PCLATH_TEMP are defined in the common RAM area
(70h - 7Fh) to avoid register bank switching during con-
text save and restore.
An input change on PORTB<7:0> sets flag bit RBIF
(INTCON<0>). The PORTB pin(s) which can individu-
ally generate interrupt is selectable in the IOCB regis-
ter. The interrupt can be enabled/disabled by setting/
clearing
enable
bit
RBIE
(INTCON<4>).
(Section 2.2.2.3)
EXAMPLE 12-1: SAVING STATUS, W, AND PCLATH REGISTERS IN RAM
#define
#define
#define
org
W_TEMP
0x70
0x71
0x72
STATUS_TEMP
PCLATH_TEMP
0x04
W_TEMP
STATUS,w
; start at Interrupt Vector
; Save W register
MOVWF
MOVF
MOVWF STATUS_TEMP
MOVF PCLATH,w
MOVWF PCLATH_TEMP
; save STATUS
; save PCLATH
:
(Interrupt Service Routine)
:
MOVF
PCLATH_TEMP,w
MOVWF PCLATH
MOVF
STATUS_TEMP,w
MOVWF STATUS
SWAPF W_TEMP,f
SWAPF W_TEMP,w
RETFIE
;
; swapf loads W without affecting STATUS flags
DS41120A-page 136
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
The WDT can be permanently disabled by program-
ming the configuration bit WDTE (Section 12.1)’0’.
12.12 Watchdog Timer (WDT)
The Watchdog Timer is a free running on-chip RC oscil-
lator, which does not require any external components.
This oscillator is in dependent from the processor
clock. The WDT will run, even if the main clock of the
device has been stopped, for example, by execution of
a SLEEPinstruction.
WDT time-out period values may be found in the Elec-
trical Specifications. Values for the WDT prescaler may
be assigned using the OPTION_REG register.
Note: The CLRWDTand SLEEPinstructions clear
the WDT and the postscaler, if assigned to
the WDT, and prevent it from timing out and
generating a device RESET condition.
During 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 TO bit in the STATUS register
will be cleared upon a Watchdog Timer time-out.
.
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.
FIGURE 12-12: WATCHDOG TIMER BLOCK DIAGRAM
From TMR0 Clock Source
(Figure 5-2)
0
Postscaler
M
U
X
1
WDT Timer
8
(1)
8 - to - 1 MUX
PS<2:0>
PSA
WDT
Enable Bit
(2)
To TMR0 (Figure 5-2)
0
1
(1)
MUX
PSA
WDT
Time-out
Note 1: PSA and PS<2:0> are bits in the OPTION_REG register.
2: WDTE bit in the configuration word.
TABLE 12-7: SUMMARY OF WATCHDOG TIMER REGISTERS
Address Name
Bit 7
Bit 6
Bit 5
MCLRE PWRTE
T0CS T0SE
Bit 4
Bit 3
WDTE FOSC2 FOSC1
PSA PS2 PS1
Bit 2
Bit 1
Bit 0
FOSC0
PS0
Config. bits(1)
BODEN
INTEDG
2007h
—
81h,181h OPTION_REG RBPU
Legend: Shaded cells are not used by the Watchdog Timer.
Note 1: See Figure 12-1 for the full description of the configuration word bits.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 137
PIC16C717/770/771
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.
12.13 Power-down Mode (SLEEP)
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).
12.13.2 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:
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.
• 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.
• 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.
12.13.1 WAKE-UP FROM SLEEP
The device can wake up from SLEEP through one of
the following events:
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.
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.
To ensure that the WDT is cleared, a CLRWDTinstruc-
tion should be executed before a SLEEPinstruction.
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 SLEEPis invoked. The TO
bit is cleared if a WDT time-out occurred (and caused
wake-up).
The following peripheral interrupts can wake the device
from SLEEP:
1. TMR1 interrupt. Timer1 must be operating as
an asynchronous counter.
2. CCP capture mode interrupt.
3. Special event trigger (Timer1 in asynchronous
mode using an external clock).
4. SSP (Start/Stop) bit detect interrupt.
5. SSP transmit or receive in slave mode (SPI/I2C).
6. A/D conversion (when A/D clock source is RC).
7. Low-voltage detect.
Other peripherals cannot generate interrupts since dur-
ing SLEEP, no on-chip clocks are present.
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
DS41120A-page 138
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 12-13: 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
Tost(1)
CLKOUT(3)
INT pin
INTF flag
(INTCON<1>)
Interrupt Latency(2)
GIE bit
(INTCON<7>)
Processor in
SLEEP
INSTRUCTION FLOW
PC
Instruction
fetched
PC
PC+1
PC+2
PC+2
PC + 2
0004h
0005h
Inst(0004h)
Inst(PC + 1)
Inst(PC + 2)
Inst(0005h)
Inst(PC) = SLEEP
Instruction
executed
Dummy cycle
Dummy cycle
SLEEP
Inst(PC + 1)
Inst(PC - 1)
Inst(0004h)
Note 1: TOST = 1024TOSC (drawing not to scale) This delay applies to LP, XT and HS modes only.
2: GIE = ’1’ assumed. In this case after wake- up, the processor jumps to the interrupt routine. If GIE = ’0’, execution will continue in-line.
3: CLKOUT is not available in these osc modes, but shown here for timing reference.
12.14 Program Verification/Code Protection
12.16 In-Circuit Serial Programming
(ICSP™)
If the code protection bit(s) have not been pro-
grammed, the on-chip program memory can be read
out for verification purposes.
PIC16CXXX 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.
Note: Microchip does not recommend code pro-
tecting windowed devices.
12.15 ID Locations
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.
For complete details of serial programming, please
refer to the In-Circuit Serial Programming (ICSP™)
Guide, (DS30277).
For ROM devices, these values are submitted along
with the ROM code.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 139
PIC16C717/770/771
NOTES:
DS41120A-page 140
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Table 13-2 lists the instructions recognized by the
MPASM assembler.
13.0 INSTRUCTION SET SUMMARY
Each PIC16CXXX 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 13-2 lists byte-oriented, bit-ori-
ented, and literal and control operations. Table 13-1
shows the opcode field descriptions.
Figure 13-1 shows the general formats that the instruc-
tions can have.
Note: To maintain upward compatibility with
future PIC16CXXX products, do not use
the OPTIONand TRISinstructions.
All examples use the following format to represent a
hexadecimal number:
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.
0xhh
where h signifies a hexadecimal digit.
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.
FIGURE 13-1: GENERAL FORMAT FOR
INSTRUCTIONS
Byte-oriented file register operations
13
8
7
6
0
0
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.
OPCODE
d
f (FILE #)
d = 0 for destination W
d = 1 for destination f
f = 7-bit file register address
For literal and control operations, ’k’ represents an
eight or eleven bit constant or literal value.
Bit-oriented file register operations
13 10 9
b (BIT #)
TABLE 13-1: OPCODE FIELD
DESCRIPTIONS
7
6
OPCODE
f (FILE #)
b = 3-bit bit address
f = 7-bit file register address
Field
Description
f
W
b
Register file address (0x00 to 0x7F)
Working register (accumulator)
Literal and control operations
Bit address within an 8-bit file register
Literal field, constant data or label
k
General
x
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.
13
8
7
0
0
OPCODE
k (literal)
k = 8-bit immediate value
d
Destination select; d = 0: store result in W,
d = 1: store result in file register f.
Default is d = 1
CALLand GOTOinstructions only
13 11 10
OPCODE
k = 11-bit immediate value
PC
TO
PD
Program Counter
Time-out bit
k (literal)
Power-down bit
The instruction set is highly orthogonal and is grouped
into three basic categories:
A description of each instruction is available in the
PICmicro™
(DS33023).
Mid-Range
Reference
Manual,
• 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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 141
PIC16C717/770/771
TABLE 13-2: PIC16CXXX 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 Add W and f
f, d AND W with f
1
1
1
1
1
1
00
00
00
00
00
00
0111 dfff ffff C,DC,Z
1,2
1,2
2
0101 dfff ffff
0001 lfff ffff
0001 0000 0011
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
-
Clear f
Clear W
f, d Complement f
f, d Decrement f
f, d Decrement f, Skip if 0
f, d Increment f
f, d Increment f, Skip if 0
f, d Inclusive OR W with f
f, d Move f
1,2
1,2
1,2,3
1,2
1,2,3
1,2
DECFSZ
INCF
1(2) 00
00
1(2) 00
1
Z
INCFSZ
IORWF
MOVF
MOVWF
NOP
RLF
RRF
SUBWF
SWAPF
XORWF
1
1
1
1
1
1
1
1
1
00
00
00
00
00
00
00
00
00
Z
Z
1,2
f
-
Move W to f
No Operation
f, d Rotate Left f through Carry
f, d Rotate Right f through Carry
f, d Subtract W from f
f, d Swap nibbles in f
f, d 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 Bit Clear f
f, b Bit Set f
f, b Bit Test f, Skip if Clear
f, b Bit Test f, Skip if Set
1
1
1 (2)
1 (2)
01 00bb bfff ffff
01 01bb bfff ffff
01 10bb bfff ffff
01 11bb bfff ffff
1,2
1,2
3
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 111x kkkk kkkk C,DC,Z
11 1001 kkkk kkkk
10 0kkk kkkk kkkk
Z
00 0000 0110 0100 TO,PD
10 1kkk kkkk kkkk
Inclusive OR literal with W
Move literal to W
11 1000 kkkk kkkk
11 00xx kkkk kkkk
00 0000 0000 1001
11 01xx kkkk kkkk
00 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
00 0000 0110 0011 TO,PD
11 110x kkkk kkkk C,DC,Z
11 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.
DS41120A-page 142
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
13.1
Instruction Descriptions
Add Literal and W
ADDLW
ANDWF
AND W with f
[label] ANDWF f,d
0 ≤ f ≤ 127
Syntax:
[label] ADDLW
0 ≤ k ≤ 255
k
Syntax:
Operands:
Operation:
Operands:
d
[0,1]
(W) + k → (W)
Operation:
(W) .AND. (f) → (destination)
Status Affected: C, DC, Z
Status Affected:
Description:
Z
Description:
The contents of the W register
are added to the eight bit literal ’k’
and the result is placed in the W
register.
AND 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'.
BCF
Bit Clear f
ADDWF
Syntax:
Add W and f
Syntax:
Operands:
[label] BCF f,b
[label] ADDWF f,d
0 ≤ f ≤ 127
0 ≤ b ≤ 7
Operands:
0 ≤ f ≤ 127
d
[0,1]
Operation:
0 → (f<b>)
Operation:
(W) + (f) → (destination)
Status Affected: None
Status Affected: C, DC, Z
Description:
Bit 'b' in register 'f' is cleared.
Description:
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 reg-
ister ’f’.
ANDLW
AND Literal with W
BSF
Bit Set f
Syntax:
[label] ANDLW
k
Syntax:
Operands:
[label] BSF f,b
Operands:
Operation:
Status Affected:
Description:
0 ≤ k ≤ 255
0 ≤ f ≤ 127
0 ≤ b ≤ 7
(W) .AND. (k) → (W)
Operation:
1 → (f<b>)
Z
Status Affected: None
The contents of W register are
AND’ed with the eight bit literal
'k'. The result is placed in the W
register.
Description:
Bit 'b' in register 'f' is set.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 143
PIC16C717/770/771
BTFSS
Bit Test f, Skip if Set
CLRF
Clear f
Syntax:
[label] BTFSS f,b
Syntax:
[label] CLRF
0 ≤ f ≤ 127
f
Operands:
0 ≤ f ≤ 127
0 ≤ b < 7
Operands:
Operation:
00h → (f)
1 → Z
Operation:
skip if (f<b>) = 1
Status Affected: None
Status Affected:
Description:
Z
Description:
If bit ’b’ in register ’f’ is ’0’, the next
The contents of register ’f’ are
cleared and the Z bit is set.
instruction is executed.
If bit ’b’ is ’1’, then the next instruc-
tion is discarded and a NOPis exe-
cuted instead making this a 2TCY
instruction.
BTFSC
Bit Test, Skip if Clear
CLRW
Clear W
Syntax:
[label] BTFSC f,b
Syntax:
[ label ] CLRW
None
Operands:
0 ≤ f ≤ 127
0 ≤ b ≤ 7
Operands:
Operation:
00h → (W)
1 → Z
Operation:
skip if (f<b>) = 0
Status Affected: None
Status Affected:
Description:
Z
Description:
If bit ’b’ in register ’f’ is ’1’, the next
W register is cleared. Zero bit (Z)
is set.
instruction is executed.
If bit ’b’, in register ’f’, is ’0’, the
next instruction is discarded, and
a NOPis executed instead, making
this a 2TCY instruction.
CLRWDT
Syntax:
Clear Watchdog Timer
[ label ] CLRWDT
None
CALL
Call Subroutine
Syntax:
[ label ] CALL k
Operands:
Operation:
Operands:
Operation:
0 ≤ k ≤ 2047
00h → WDT
0 → WDT prescaler,
1 → TO
(PC)+ 1→ TOS,
k → PC<10:0>,
(PCLATH<4:3>) → PC<12:11>
1 → PD
Status Affected: None
Status Affected: TO, PD
Description:
Call Subroutine. First, return
Description: CLRWDTinstruction resets the
address (PC+1) is pushed onto
the stack. The eleven bit immedi-
ate address is loaded into PC bits
<10:0>. The upper bits of the PC
are loaded from PCLATH. CALLis
a two cycle instruction.
Watchdog Timer. It also resets
the prescaler of the WDT. Status
bits TO and PD are set.
DS41120A-page 144
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
COMF
Complement f
[ label ] COMF f,d
0 ≤ f ≤ 127
GOTO
Unconditional Branch
[ label ] GOTO k
0 ≤ k ≤ 2047
Syntax:
Operands:
Syntax:
Operands:
Operation:
d
[0,1]
k → PC<10:0>
Operation:
(f) → (destination)
PCLATH<4:3> → PC<12:11>
Status Affected:
Description:
Z
Status Affected: None
The contents of register ’f’ are
complemented. If ’d’ is 0, the
result is stored in W. If ’d’ is 1, the
result is stored back in register ’f’.
Description:
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.
DECF
Decrement f
[label] DECF f,d
0 ≤ f ≤ 127
INCF
Increment f
Syntax:
Operands:
Syntax:
Operands:
[ label ] INCF f,d
0 ≤ f ≤ 127
d
[0,1]
d
[0,1]
Operation:
(f) - 1 → (destination)
Operation:
(f) + 1 → (destination)
Status Affected:
Description:
Z
Status Affected:
Description:
Z
Decrement 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’.
The contents of register ’f’ are
incremented. If ’d’ is 0, the result
is placed in the W register. If ’d’ is
1, the result is placed back in reg-
ister ’f’.
DECFSZ
Syntax:
Decrement f, Skip if 0
[ label ] DECFSZ f,d
0 ≤ f ≤ 127
INCFSZ
Syntax:
Increment f, Skip if 0
[ label ] INCFSZ f,d
0 ≤ f ≤ 127
Operands:
d
[0,1]
Operands:
Operation:
(f) - 1 → (destination);
skip if result = 0
d
[0,1]
Operation:
(f) + 1 → (destination),
skip if result = 0
Status Affected: None
Description: The contents of register ’f’ are
Status Affected: None
decremented. If ’d’ is 0, the result
is placed in the W register. If ’d’ is
1, the result is placed back in reg-
ister ’f’.
If the result is 1, the next instruc-
tion is executed. If the result is 0,
then a NOPis executed instead
making it a 2TCY instruction.
Description:
The contents of register ’f’ are
incremented. If ’d’ is 0, the result is
placed in the W register. If ’d’ is 1,
the result is placed back in regis-
ter ’f’.
If the result is 1, the next instruc-
tion is executed. If the result is 0, a
NOPis executed instead making it
a 2TCY instruction.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 145
PIC16C717/770/771
IORLW
Inclusive OR Literal with W
[ label ] IORLW k
0 ≤ k ≤ 255
MOVLW
Move Literal to W
[ label ] MOVLW k
0 ≤ k ≤ 255
Syntax:
Syntax:
Operands:
Operation:
Status Affected:
Description:
Operands:
Operation:
(W) .OR. k → (W)
Z
k → (W)
Status Affected: None
The contents of the W register are
OR’ed with the eight bit literal 'k'.
The result is placed in the W reg-
ister.
Description:
The eight bit literal 'k' is loaded
into W register. The don’t cares
will assemble as 0’s.
MOVWF
Syntax:
Move W to f
IORWF
Inclusive OR W with f
[ label ] IORWF f,d
0 ≤ f ≤ 127
[ label ] MOVWF
0 ≤ f ≤ 127
f
Syntax:
Operands:
Operation:
Operands:
(W) → (f)
d
[0,1]
Status Affected: None
Operation:
(W) .OR. (f) → (destination)
Description:
Move data from W register to reg-
ister 'f'.
Status Affected:
Description:
Z
Inclusive OR the W register with
register 'f'. If 'd' is 0 the result is
placed in the W register. If 'd' is 1
the result is placed back in regis-
ter 'f'.
NOP
No Operation
[ label ] NOP
None
Syntax:
MOVF
Move f
Operands:
Operation:
Syntax:
Operands:
[ label ] MOVF f,d
0 ≤ f ≤ 127
No operation
Status Affected: None
Description: No operation.
d
[0,1]
Operation:
(f) → (destination)
Status Affected:
Description:
Z
The contents of register f are
moved to a destination dependant
upon the status of d. If d = 0, des-
tination is W register. If d = 1, the
destination is file register f itself. d
= 1 is useful to test a file register
since status flag Z is affected.
DS41120A-page 146
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
RETFIE
Return from Interrupt
[ label ] RETFIE
None
RLF
Rotate Left f through Carry
Syntax:
Syntax:
[ label ] RLF f,d
Operands:
Operation:
Operands:
0 ≤ f ≤ 127
d
[0,1]
TOS → PC,
1 → GIE
Operation:
See description below
C
Status Affected: None
Status Affected:
Description:
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’.
C
Register f
RETLW
Return with Literal in W
Syntax:
[ label ] RETLW k
RRF
Rotate Right f through Carry
[ label ] RRF f,d
0 ≤ f ≤ 127
Operands:
Operation:
0 ≤ k ≤ 255
Syntax:
Operands:
k → (W);
TOS → PC
d
[0,1]
Status Affected: None
Operation:
See description below
C
Description:
The W register is loaded with the
Status Affected:
Description:
eight bit literal ’k’. The program
counter is loaded from the top of
the stack (the return address).
This is a two cycle instruction.
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 reg-
ister ’f’.
C
Register f
RETURN
Syntax:
Return from Subroutine
[ label ] RETURN
None
SLEEP
Operands:
Operation:
Syntax:
[ label
]
TOS → PC
SLEEP
Status Affected: None
Operands:
Operation:
None
Description: Return from subroutine. The stack
00h → WDT,
0 → WDT prescaler,
1 → TO,
is POPed and the top of the stack
(TOS) is loaded into the program
counter. This is a two cycle
instruction.
0 → PD
Status Affected:
Description:
TO, PD
The power-down status bit, PD is
cleared. Time-out status bit, TO
is set. Watchdog Timer and its
prescaler are cleared.
The processor is put into SLEEP
mode with the oscillator stopped.
See Section 13.8 for more
details.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 147
PIC16C717/770/771
SUBLW
Subtract W from Literal
XORLW
Exclusive OR Literal with W
Syntax:
[ label ]
Syntax:
[label]
SUBLW k
XORLW k
Operands:
Operation:
0 ≤ k ≤ 255
Operands:
0 ≤ k ≤ 255
k - (W) → (W)
Operation:
(W) .XOR. k → (W)
Status Affected: C, DC, Z
Status Affected:
Description:
Z
Description:
The W register is subtracted (2’s
The contents of the W register
are XOR’ed with the eight bit lit-
eral 'k'. The result is placed in
the W register.
complement method) from the
eight bit literal 'k'. The result is
placed in the W register.
XORWF
Syntax:
Exclusive OR W with f
[label] XORWF f,d
0 ≤ f ≤ 127
SUBWF
Subtract W from f
Syntax:
[ label ]
SUBWF f,d
Operands:
Operands:
0 ≤ f ≤ 127
d
[0,1]
d
[0,1]
Operation:
(W) .XOR. (f) → (destination)
Operation:
(f) - (W) → (destination)
Status Affected:
Description:
Z
Status Affected: C, DC, Z
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:
Subtract (2’s complement method)
W register from 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'.
SWAPF
Syntax:
Swap Nibbles in f
[ label ] SWAPF f,d
0 ≤ f ≤ 127
Operands:
d
[0,1]
Operation:
(f<3:0>) → (destination<7:4>),
(f<7:4>) → (destination<3:0>)
Status Affected: None
Description:
The upper and lower nibbles of
register 'f' are exchanged. If 'd' is
0, the result is placed in W regis-
ter. If 'd' is 1, the result is placed in
register 'f'.
DS41120A-page 148
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
MPLAB allows you to:
14.0 DEVELOPMENT SUPPORT
The PICmicro® microcontrollers are supported with a
full range of hardware and software development tools:
• Edit your source files (either assembly or ‘C’)
• One touch assemble (or compile) and download
to PICmicro tools (automatically updates all
project information)
• Integrated Development Environment
- MPLAB™ IDE Software
• Debug using:
- source files
• Assemblers/Compilers/Linkers
- MPASM Assembler
- absolute listing file
- object code
- MPLAB-C17 and MPLAB-C18 C Compilers
- MPLINK/MPLIB Linker/Librarian
• Simulators
The ability to use MPLAB with Microchip’s simulator,
MPLAB-SIM, allows a consistent platform and the abil-
ity to easily switch from the cost-effective simulator to
the full featured emulator with minimal retraining.
- MPLAB-SIM Software Simulator
• Emulators
- MPLAB-ICE Real-Time In-Circuit Emulator
- PICMASTER®/PICMASTER-CE In-Circuit
14.2
MPASM Assembler
Emulator
MPASM is a full featured universal macro assembler for
all PICmicro MCU’s. It can produce absolute code
directly in the form of HEX files for device program-
mers, or it can generate relocatable objects for
MPLINK.
- ICEPIC™
• In-Circuit Debugger
- MPLAB-ICD for PIC16F877
• Device Programmers
MPASM has a command line interface and a Windows
shell and can be used as a standalone application on a
Windows 3.x or greater system. MPASM generates
relocatable object files, Intel standard HEX files, MAP
files to detail memory usage and symbol reference, an
absolute LST file which contains source lines and gen-
erated machine code, and a COD file for MPLAB
debugging.
- PRO MATE II Universal Programmer
- PICSTART Plus Entry-Level Prototype
Programmer
• Low-Cost Demonstration Boards
- SIMICE
- PICDEM-1
- PICDEM-2
- PICDEM-3
MPASM features include:
- PICDEM-17
- SEEVAL
• MPASM and MPLINK are integrated into MPLAB
projects.
- KEELOQ
• MPASM allows user defined macros to be created
for streamlined assembly.
14.1
MPLAB Integrated Development
Environment Software
• MPASM allows conditional assembly for multi pur-
pose source files.
• MPASM directives allow complete control over the
assembly process.
The MPLAB IDE software brings an ease of software
development previously unseen in the 8-bit microcon-
troller market. MPLAB is a Windows -based applica-
tion which contains:
14.3
MPLAB-C17 and MPLAB-C18
C Compilers
• Multiple functionality
- editor
The MPLAB-C17 and MPLAB-C18 Code Development
Systems are complete ANSI ‘C’ compilers and inte-
grated development environments for Microchip’s
PIC17CXXX and PIC18CXXX family of microcontrol-
lers, respectively. These compilers provide powerful
integration capabilities and ease of use not found with
other compilers.
- simulator
- programmer (sold separately)
- emulator (sold separately)
• A full featured editor
• A project manager
• Customizable tool bar and key mapping
• A status bar
For easier source level debugging, the compilers pro-
vide symbol information that is compatible with the
MPLAB IDE memory display.
• On-line help
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 149
PIC16C717/770/771
Interchangeable processor modules allow the system
to be easily reconfigured for emulation of different pro-
cessors. The universal architecture of the MPLAB-ICE
allows expansion to support new PICmicro microcon-
trollers.
14.4
MPLINK/MPLIB Linker/Librarian
MPLINK is a relocatable linker for MPASM and
MPLAB-C17 and MPLAB-C18. It can link relocatable
objects from assembly or C source files along with pre-
compiled libraries using directives from a linker script.
The MPLAB-ICE Emulator System has been designed
as a real-time emulation system with advanced fea-
tures that are generally found on more expensive devel-
opment tools. The PC platform and Microsoft® Windows
3.x/95/98 environment were chosen to best make these
features available to you, the end user.
MPLIB is a librarian for pre-compiled code to be used
with MPLINK. When a routine from a library is called
from another source file, only the modules that contains
that routine will be linked in with the application. This
allows large libraries to be used efficiently in many dif-
ferent applications. MPLIB manages the creation and
modification of library files.
MPLAB-ICE 2000 is a full-featured emulator system
with enhanced trace, trigger, and data monitoring fea-
tures. Both systems use the same processor modules
and will operate across the full operating speed range
of the PICmicro MCU.
MPLINK features include:
• MPLINK works with MPASM and MPLAB-C17
and MPLAB-C18.
• MPLINK allows all memory areas to be defined as
sections to provide link-time flexibility.
14.7
PICMASTER/PICMASTER CE
The PICMASTER system from Microchip Technology is
a full-featured, professional quality emulator system.
This flexible in-circuit emulator provides a high-quality,
universal platform for emulating Microchip 8-bit
PICmicro microcontrollers (MCUs). PICMASTER sys-
tems are sold worldwide, with a CE compliant model
available for European Union (EU) countries.
MPLIB features include:
• MPLIB makes linking easier because single librar-
ies can be included instead of many smaller files.
• MPLIB helps keep code maintainable by grouping
related modules together.
• MPLIB commands allow libraries to be created
and modules to be added, listed, replaced,
deleted, or extracted.
14.8
ICEPIC
ICEPIC is a low-cost in-circuit emulation solution for the
Microchip Technology PIC16C5X, PIC16C6X,
PIC16C7X, and PIC16CXXX families of 8-bit one-time-
programmable (OTP) microcontrollers. The modular
system can support different subsets of PIC16C5X or
PIC16CXXX products through the use of
interchangeable personality modules or daughter
boards. The emulator is capable of emulating without
target application circuitry being present.
14.5
MPLAB-SIM Software Simulator
The MPLAB-SIM Software Simulator allows code
development in a PC host environment by simulating
the PICmicro series microcontrollers on an instruction
level. On any given instruction, the data areas can be
examined or modified and stimuli can be applied from
a file or user-defined key press to any of the pins. The
execution can be performed in single step, execute until
break, or trace mode.
14.9
MPLAB-ICD In-Circuit Debugger
MPLAB-SIM fully supports symbolic debugging using
MPLAB-C17 and MPLAB-C18 and MPASM. The Soft-
ware Simulator offers the flexibility to develop and
debug code outside of the laboratory environment mak-
ing it an excellent multi-project software development
tool.
Microchip’s In-Circuit Debugger, MPLAB-ICD, is a pow-
erful, low-cost run-time development tool. This tool is
based on the flash PIC16F877 and can be used to
develop for this and other PICmicro microcontrollers
from the PIC16CXXX family. MPLAB-ICD utilizes the
In-Circuit Debugging capability built into the
PIC16F87X. This feature, along with Microchip’s In-Cir-
cuit Serial Programming protocol, offers cost-effective
in-circuit flash programming and debugging from the
graphical user interface of the MPLAB Integrated
Development Environment. This enables a designer to
develop and debug source code by watching variables,
single-stepping and setting break points. Running at
full speed enables testing hardware in real-time. The
MPLAB-ICD is also a programmer for the flash
PIC16F87X family.
14.6
MPLAB-ICE High Performance
Universal In-Circuit Emulator with
MPLAB IDE
The MPLAB-ICE Universal In-Circuit Emulator is
intended to provide the product development engineer
with a complete microcontroller design tool set for
PICmicro microcontrollers (MCUs). Software control of
MPLAB-ICE is provided by the MPLAB Integrated
Development Environment (IDE), which allows editing,
“make” and download, and source debugging from a
single environment.
DS41120A-page 150
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
the PICDEM-1 board, on a PRO MATE II or
PICSTART-Plus programmer, and easily test firm-
ware. The user can also connect the PICDEM-1
board to the MPLAB-ICE emulator and download the
firmware to the emulator for testing. Additional proto-
type 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.
14.10 PRO MATE II Universal 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. PRO MATE II is CE
compliant.
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 instructions and 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
program PICmicro devices. It can also set code-protect
bits in this mode.
14.14 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-Plus, and easily test firmware.
The MPLAB-ICE 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
usage of the I2C bus and separate headers for connec-
tion to an LCD module and a keypad.
14.11 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 supports all PICmicro devices with up
to 40 pins. Larger pin count devices such as the
PIC16C92X, and PIC17C76X may be supported with
an adapter socket. PICSTART Plus is CE compliant.
14.12 SIMICE Entry-Level
Hardware Simulator
SIMICE is an entry-level hardware development sys-
tem designed to operate in a PC-based environment
with Microchip’s simulator MPLAB-SIM. Both SIMICE
and MPLAB-SIM run under Microchip Technology’s
MPLAB Integrated Development Environment (IDE)
software. Specifically, SIMICE provides hardware sim-
ulation for Microchip’s PIC12C5XX, PIC12CE5XX, and
PIC16C5X families of PICmicro 8-bit microcontrollers.
SIMICE works in conjunction with MPLAB-SIM to pro-
vide non-real-time I/O port emulation. SIMICE enables
a developer to run simulator code for driving the target
system. In addition, the target system can provide input
to the simulator code. This capability allows for simple
and interactive debugging without having to manually
generate MPLAB-SIM stimulus files. SIMICE is a valu-
able debugging tool for entry-level system develop-
ment.
14.15 PICDEM-3 Low-Cost PIC16CXXX
Demonstration Board
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 MPLAB-ICE 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
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.
14.13 PICDEM-1 Low-Cost PICmicro
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
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 151
PIC16C717/770/771
14.16 PICDEM-17
The PICDEM-17 is an evaluation board that demon-
strates the capabilities of several Microchip microcon-
trollers,
including
PIC17C752,
PIC17C756,
PIC17C762, and PIC17C766. All necessary hardware
is included to run basic demo programs, which are sup-
plied on a 3.5-inch disk. A programmed sample is
included, and the user may erase it and program it with
the other sample programs using the PRO MATE II or
PICSTART Plus device programmers and easily debug
and test the sample code. In addition, PICDEM-17 sup-
ports down-loading of programs to and executing out of
external FLASH memory on board. The PICDEM-17 is
also usable with the MPLAB-ICE or PICMASTER emu-
lator, and all of the sample programs can be run and
modified using either emulator. Additionally, a gener-
ous prototype area is available for user hardware.
14.17 SEEVAL Evaluation and Programming
System
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.
14.18 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.
DS41120A-page 152
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 14-1: DEVELOPMENT TOOLS FROM MICROCHIP
5 1 2 0 P M C
X X R X F C M
X X
H C S X
X X C 9 3
/ X X C 2 5
/ X X C 2 4
X X C 8 2 C 1 P I
X X 7 C 7 C 1 P I
X 4 C 7 C 1 P I
X X 9 C 6 C 1 P I
X 8 X 1 6 C I F P
X 8 C 6 C 1 P I
X X 7 C 6 C 1 P I
X 7 C 6 C 1 P I
X 6 2 6 1 F C I P
X X C 6 X C 1 P I
X 6 C 6 C 1 P I
X 5 C 6 C 1 P I
0 0 4 0 1 C I P
X X C 2 X C 1 P I
s l o o e T a r f t o w S s r o t a u l E m e r g g b e u D s m e a r m o g P r r
t i s K v a E l d a n d s a r o B o m e D
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 153
PIC16C717/770/771
NOTES:
DS41120A-page 154
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
15.0 ELECTRICAL CHARACTERISTICS
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
Maximum voltage between AVDD and VDD pins................................................................................................................. ± 0.3V
Maximum voltage between AVSS and VSS pins ................................................................................................................. ± 0.3V
Voltage on MCLR with respect to VSS........................................................................................................ -0.3V to +8.5V
Voltage on RA4 with respect to Vss......................................................................................................... -0.3V to +10.5V
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
Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - ∑ IOH} + ∑ {(VDD - VOH) x IOH} + ∑(VOl x IOL).
† 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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 155
PIC16C717/770/771
FIGURE 15-1: PIC16C717/770/771 VOLTAGE-FREQUENCY GRAPH, -40°C ≤ TA ≤ +85°C
6.0
5.5
5.0
4.5
VDD
(Volts)
4.0
3.5
3.0
2.5
0
4
10
20
25
Frequency (MHz)
Note 1: The shaded region indicates the permissible combinations of voltage and frequency.
FIGURE 15-2: PIC16LC717/770/771 VOLTAGE-FREQUENCY GRAPH, 0°C ≤ TA ≤ +70°C
6.0
5.5
5.0
4.5
VDD
(Volts)
4.0
3.5
3.0
2.5
0
4
10
20
25
Frequency (MHz)
Note 1: The shaded region indicates the permissible combinations of voltage and frequency.
DS41120A-page 156
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 15-3: PIC16LC717/770/771 VOLTAGE-FREQUENCY GRAPH,
-40°C ≤ TA ≤ 0°C, +70°C ≤ TA ≤ +85°C
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
VDD
(Volts)
0
4
10
20
25
Frequency (MHz)
Note 1: The shaded region indicates the permissible combinations of voltage and frequency.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 157
PIC16C717/770/771
15.1
DC Characteristics: PIC16C717/770/771 (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.
Sym
Characteristic
Min
Typ† Max Units
Conditions
D001
VDD
Supply Voltage
4.0
—
5.5
—
V
D002*
VDR
RAM Data Retention
—
1.5
V
(1)
Voltage
D003
D004*
D010
VPOR
SVDD
IDD
VDD start voltage to
ensure internal Power-on Reset signal
—
VSS
—
—
V
See section on Power-on Reset for
details
VDD rise rate to ensure internal Power-
on Reset signal
0.05
—
V/ms See section on Power-on Reset for
details. PWRT enabled
(2)
TBD
TBD
TBD
TBD
mA
mA
mA
mA
FOSC = 20 MHz, VDD = 5.5V*
FOSC = 20 MHz, VDD = 4.0V
FOSC = 4 MHz, VDD = 4.0V*
FOSC = 32 KHz, VDD = 4.0V
Supply Current
(3)
D020
D020A
IPD
—
—
—
TBD
16
19
mA
µA
µA
VDD = 5.5V, 0°C to +70°C*
VDD = 4.0V, 0°C to +70°C
VDD = 4.0V, -40°C to +85°C
Power-down Current
1.5
1.5
(5)
Module Differential Current
D021
∆IWDT
Watchdog Timer
—
—
6.0
20
µA
µA
VDD = 4.0V
VDD = 4.0V
(6)
∆IBG
D023B*
Bandgap voltage generator
40µA TBD
D025*
D026*
∆IT1OSC Timer1 oscillator
—
—
5
300
10
10
70
70
9
µA
µA
µA
µA
µA
µA
VDD = 4.0V
∆IAD
A/D Converter
—
VDD = 5.5V, A/D on, not converting
VDD = 4.0V*
∆ILVD
∆IPBOR
∆IVRH
∆IVRL
Fosc
Low Voltage Detect
TBD
TBD
TBD
TBD
Programmable Brown-Out Reset
Voltage Reference High
Voltage Reference Low
PBOR enabled, VDD = 5.0V*
VDD = 5.0V, no load on VRH*
VDD = 4.0V, no load on VRL*
1A
LP oscillator, operating freq.
9
—
—
TBD
—
0
—
4
200
—
—
KHz All temperatures
MHz All temperatures, OSCF = 1
MHz All temperatures, OSCF = 0
INTRC oscillator operating freq.
37
—
37
—
—
ER oscillator operating freq.
TBD MHz All temperatures, OSCF = 1
—
4
MHz All temperatures, OSCF = 0
MHz All temperatures
MHz All temperatures
XT oscillator operating freq.
HS oscillator operating freq.
0
20
*
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 consump-
tion.
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 or VSS.
4: For ER osc configuration, current through Rext is not included. The current through the resistor can be estimated by the for-
mula Ir = TBD with Rext in kOhm.
5: The ∆ current is the additional current consumed when the peripheral is enabled. This current should be added to the base
(IPD or IDD) current.
6: The bandgap voltage reference provides 1.22V nominal to the VRL, VRH, LVD and BOR circuits. When calculating current con-
sumption use the following formula: ∆IVRL + ∆IVRH + ∆ILVD + ∆IBOR + ∆IBG. Any of the ∆IVRL, ∆IVRH, ∆ILVD or ∆IBOR can be 0.
DS41120A-page 158
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
15.2
DC Characteristics: PIC16LC717/770/771 (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.
Sym
Characteristic
Min
Typ† Max Units
Conditions
D001
VDD
Supply Voltage
2.5
—
5.5
—
V
V
(1)
D002*
VDR
—
1.5
RAM Data Retention Voltage
D003
D004*
D010
VPOR
VDD start voltage to ensure
internal Power-on Reset signal
—
VSS
—
V
See section on Power-on Reset for details
SVDD
VDD rise rate to ensure internal 0.05
Power-on Reset signal
—
—
V/ms See section on Power-on Reset for details.
PWRT enabled
Supply
Current
IDD
TBD
mA
FOSC = 20 MHz, VDD = 5.5V*
(2)
TBD
TBD
TBD
mA
mA
mA
FOSC = 20 MHz, VDD = 4.0V
FOSC = 10 MHz, VDD = 3.0V
FOSC = 4 MHz, VDD = 2.5V
TBD
mA
FOSC = 32 KHz, VDD = 2.5V
(3)
D020
D020A
IPD
—
—
—
—
—
TBD TBD
µA
µA
µA
µA
µA
VDD = 5.5V, 0°C to +70°C
VDD = 4.0V, 0°C to +70°C
VDD = 4.0V, -40°C to +85°C
VDD = 2.5V, 0°C to +70°C
VDD = 3.0V, -40°C to +85°C
Power-down Current
1.5
1.5
0.9
0.9
16
19
5
5
(5)
Module Differential Current
D021
D023B* ∆IBG
∆IWDT
Watchdog Timer
Bandgap voltage generator
Timer1 oscillator
—
—
6
40
20
TBD
µA
µA
VDD = 3.0V
VDD = 3.0V
D025*
D026*
∆IT1OSC
—
—
1.5
300
10
3
µA
µA
µA
µA
VDD = 3.0V
∆IAD
A/D Converter
—
VDD = 5.5V, A/D on, not converting
VDD = 4.0V*
∆ILVD
∆IPBOR
Low Voltage Detect
TBD
TBD
Programmable Brown-Out
Reset
10
PBOR enabled, VDD = 5.0V*
∆IVRH
∆IVRL
Fosc
Voltage Reference High
Voltage Reference Low
70
70
TBD
TBD
µA
µA
VDD = 5.0V, no load on VRH*
VDD = 4.0V, no load on VRL*
1A
LP oscillator, operating freq.
INTRC oscillator operating freq.
9
—
—
TBD
—
0
—
4
200
—
—
KHz All temperatures
MHz All temperatures, OSCF = 1
MHz All temperatures, OSCF = 0
37
—
37
—
—
ER oscillator operating freq.
TBD MHz All temperatures, OSCF = 1
—
4
MHz All temperatures, OSCF = 0
MHz All temperatures
MHz All temperatures
XT oscillator operating freq.
HS oscillator operating freq.
0
20
*
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 con-
sumption.
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 or VSS.
4: For ER osc configuration, current through Rext is not included. The current through the resistor can be estimated by the
formula Ir = VDD/2Rext (mA) with Rext in kOhm.
5: The ∆ current is the additional current consumed when the peripheral is enabled. This current should be added to the base
(IPD or IDD) current.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 159
PIC16C717/770/771
15.3
DC Characteristics: PIC16C717/770/771 & PIC16LC717/770/771 (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 15.1
and Section 15.2.
Param
No.
Sym
Characteristic
Min
Typ†
Max
Units
Conditions
Input Low Voltage
I/O ports
with TTL buffer
VIL
D030
VSS
VSS
VSS
VSS
—
—
—
—
0.15VDD
0.8V
V
V
V
V
For entire VDD range
D030A
D031
D032
4.5V ≤ VDD ≤ 5.5V
with Schmitt Trigger buffer
MCLR
0.2VDD
0.2VDD
For entire VDD range
D033
OSC1 (in XT, HS, LP and EC)
Input High Voltage
I/O ports
VSS
—
0.3VDD
V
VIH
—
with TTL buffer
D040
2.0
(0.25VDD
+ 0.8V)
0.8VDD
0.8VDD
0.7VDD
50
—
—
VDD
VDD
V
V
4.5V ≤ VDD ≤ 5.5V
D040A
For entire VDD range
D041
D042
D042A
D070
with Schmitt Trigger buffer
MCLR
—
—
VDD
VDD
VDD
400
V
V
V
For entire VDD range
OSC1 (XT, HS, LP and EC)
—
IPURB PORTB weak pull-up current per pin
250
µA VDD = 5V, VPIN = VSS
(1,2)
Input Leakage Current
D060
IIL
IIL
I/O ports (with digital functions)
—
—
—
—
±1
µA Vss ≤ VPIN ≤ VDD, Pin at hi-imped-
ance
D060A
I/O ports (with analog functions)
±100
nA Vss ≤ VPIN ≤ VDD, Pin at hi-imped-
ance
D061
D063
RA5/MCLR/VPP
—
—
—
—
±5
±5
µA Vss ≤ VPIN ≤ VDD
µA Vss ≤ VPIN ≤ VDD, XT, HS, LP and EC
osc configuration
OSC1
Output Low Voltage
D080
VOL I/O ports
Output High Voltage
—
—
0.6
V
IOL = 8.5 mA, VDD = 4.5V
(2)
D090
VOH
VDD - 0.7
—
—
—
V
V
IOH = -3.0 mA, VDD = 4.5V
I/O ports
D150*
VOD Open-Drain High Voltage
Capacitive Loading Specs on Out-
put Pins*
—
10.5
RA4 pin
D100
COSC2 OSC2 pin
—
—
15
pF In XT, HS and LP modes when exter-
nal clock is used to drive OSC1.
D101
D102
CIO All I/O pins and OSC2 (in RC mode)
—
—
—
—
50
400
pF
pF
2
CB
SCL, SDA in I C mode
CVRH VRH pin
CVRL VRL pin
—
—
—
—
200
200
pF VRH output enabled
pF VRL output enabled
*
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: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels represent nor-
mal operating conditions. Higher leakage current may be measured at different input voltages.
2: Negative current is defined as current sourced by the pin.
DS41120A-page 160
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
15.4
AC Characteristics: PIC16C717/770/771 & PIC16LC717/770/771 (Commercial, Industrial)
15.4.1 TIMING PARAMETER SYMBOLOGY
The timing parameter symbols have been created following one of the following formats:
1. TppS2ppS
3. TCC:ST
4. Ts
(I2C specifications only)
(I2C specifications only)
2. TppS
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
I2C only
AA
output access
Bus free
High
Low
High
Low
BUF
TCC:ST (I2C specifications only)
CC
HD
ST
DAT
STA
Hold
SU
Setup
DATA input hold
START condition
STO
STOP condition
FIGURE 15-4: LOAD CONDITIONS
Load condition 1
Load condition 2
VDD/2
RL
CL
CL
Pin
Pin
VSS
VSS
RL = 464Ω
CL = 50 pF
15 pF
for all pins except OSC2
for OSC2 output
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 161
PIC16C717/770/771
15.4.2 TIMING DIAGRAMS AND SPECIFICATIONS
FIGURE 15-5: 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 15-4 for load conditions.
TABLE 15-1: CLKOUT AND I/O TIMING REQUIREMENTS
Parameter
No.
Sym
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
PIC16C717/770/771
PIC16LC717/770/771
18*
TosH2ioI
OSC1↑ (Q2 cycle) to
Port input invalid (I/O in
hold time)
100
200
—
—
—
—
ns
ns
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
PIC16C717/770/771
PIC16LC717/770/771
PIC16C717/770/771
PIC16LC717/770/771
TioR
Port output rise time
Port output fall time
INT pin high or low time
—
21*
TioF
—
—
22††*
23††*
Tinp
Trbp
TCY
TCY
RB7:RB0 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.
DS41120A-page 162
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 15-6: EXTERNAL CLOCK TIMING
Q4
Q1
Q2
Q3
Q4
Q1
OSC1
1
3
4
3
4
2
CLKOUT
TABLE 15-2: EXTERNAL CLOCK TIMING REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units Conditions
1A
FOSC
External CLKIN Frequency
(Note 1)
DC
DC
DC
DC
0.1
—
—
—
—
—
4
20
20
200
4
MHz XT osc mode
MHz EC osc mode
MHz HS osc mode
kHz LP osc mode
MHz XT osc mode
Oscillator Frequency
(Note 1)
4
5
—
—
20
200
MHz HS osc mode
kHz LP osc mode
1
TOSC
External CLKIN Period
(Note 1)
250
50
—
—
—
—
ns
ns
ns
µs
ns
ns
µs
ns
ns
µs
ns
XT and RC osc mode
EC osc mode
HS osc mode
LP osc mode
XT osc mode
HS osc mode
LP osc mode
TCY = 4/FOSC
XT oscillator
LP oscillator
HS oscillator
EC oscillator
XT oscillator
LP oscillator
HS oscillator
EC oscillator
50
—
—
5
—
—
Oscillator Period
(Note 1)
250
50
—
10,000
250
—
—
5
—
2
TCY
Instruction Cycle Time (Note 1)
200
100
2.5
15
TCY
—
DC
—
3*
TosL,
TosH
External Clock in (OSC1) High or
Low Time
—
—
—
—
4*
TosR,
TosF
External Clock in (OSC1) Rise or
Fall Time
—
—
—
—
—
—
25
50
15
ns
ns
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.
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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 163
PIC16C717/770/771
TABLE 15-3: CALIBRATED INTERNAL RC FREQUENCIES - PIC16C717/770/771 AND
PIC16LC717/770/771
AC Characteristics
Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial),
–40°C ≤ TA ≤ +85°C (industrial),
Operating Voltage VDD range is described in Section 15.1 and Section 15.2
Parameter
Sym
Typ(1)
Characteristic
Min*
Max* Units
Conditions
MHz VDD = 5.0V
MHz VDD = 2.5V
No.
Internal Calibrated RC Frequency
3.65
4.00
4.28
4.31
Internal Calibrated RC Frequency
3.55
4.00
*
These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
FIGURE 15-7: 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 15-4 for load conditions.
FIGURE 15-8: BROWN-OUT RESET TIMING
BVDD
VDD
35
DS41120A-page 164
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 15-4: 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
—
—
µs VDD = 5V, -40°C to +85°C
ms VDD = 5V, -40°C to +85°C
31*
TWDT
Watchdog Timer Time-out Period
(No Prescaler)
7
18
33
32*
33*
34*
TOST
TPWRT
TIOZ
Oscillation Start-up Timer Period
Power up Timer Period
—
28
—
1024 TOSC
—
132
2.1
—
TOSC = OSC1 period
72
—
ms VDD = 5V, -40°C to +85°C
µs
I/O Hi-impedance from MCLR Low
or Watchdog Timer Reset
35*
*
TBOR
Brown-out Reset pulse width
100
—
—
µs
VDD ≤ VBOR (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.
FIGURE 15-9: BROWN-OUT RESET CHARACTERISTICS
VDD
VBOR
(device not in Brown-out Reset)
(device in Brown-out Reset)
RESET (due to BOR)
72 ms time out
FIGURE 15-10: 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 15-4 for load conditions.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 165
PIC16C717/770/771
TABLE 15-5: 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, PIC16C717/770/771
ns
ns
Prescaler =
2,4,8
PIC16LC717/770/771
25
Asynchronous PIC16C717/770/771
PIC16LC717/770/771
30
—
—
—
—
—
—
—
—
—
—
ns
ns
50
0.5TCY + 20
15
T1CKI Low Time
Synchronous, Prescaler = 1
ns Must also meet
parameter 47
Synchronous, PIC16C717/770/771
ns
ns
Prescaler =
2,4,8
PIC16LC717/770/771
25
Asynchronous PIC16C717/770/771
PIC16LC717/770/771
30
50
—
—
—
—
—
—
ns
ns
T1CKI input period Synchronous
PIC16C717/770/771 Greater of:
ns N = prescale value
(1, 2, 4, 8)
30 OR TCY + 40
N
PIC16LC717/770/771 Greater of:
—
—
ns N = prescale value
(1, 2, 4, 8)
50 OR TCY + 40
N
Asynchronous PIC16C717/770/771
PIC16LC717/770/771
Timer1 oscillator input frequency range
(oscillator enabled by setting bit T1OSCEN)
60
—
—
—
—
—
50
ns
ns
100
DC
Ft1
kHz
48
*
Tcke2tmr1 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.
FIGURE 15-11: ENHANCED CAPTURE/COMPARE/PWM TIMINGS (ECCP1)
RB3/CCP1/P1A
(Capture Mode)
50
51
52
RB3/CCP1/P1A
(Compare or PWM Mode)
53
Note: Refer to Figure 15-4 for load conditions.
54
DS41120A-page 166
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
TABLE 15-6: ENHANCED CAPTURE/COMPARE/PWM REQUIREMENTS (ECCP1)
Param Sym Characteristic
No.
Min
Typ† Max Units Conditions
50*
TccL CCP1 input low
time
No Prescaler
0.5TCY + 20
—
—
ns
PIC16C717/770/771
PIC16LC717/770/771
10
—
—
—
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
ns
With Prescaler
No Prescaler
20
51*
TccH
0.5TCY + 20
CCP1 input high
time
PIC16C717/770/771
PIC16LC717/770/771
10
20
With Prescaler
52*
53*
TccP
3TCY + 40
ns N = prescale value
(1,4 or 16)
CCP1 input period
N
PIC16C717/770/771
PIC16LC717/770/771
PIC16C717/770/771
PIC16LC717/770/771
TccR CCP1 output fall time
TccF CCP1 output fall time
—
—
—
—
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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 167
PIC16C717/770/771
15.5
Analog Peripherals Characteristics:
PIC16C717/770/771 & PIC16LC717/
770/771 (Commercial, Industrial)
15.5.1 BANDGAP MODULE
FIGURE 15-12: BANDGAP START-UP TIME
VBGAP
VBGAP = 1.2V
(internal use only)
Enable Bandgap
TBGAP
Bandgap stable
TABLE 15-7: BANDGAP START-UP TIME
Parameter
No.
Sym Characteristic
Min
Typ†
Max Units
TBD
Conditions
36*
TBGAP
Bandgap start-up time
—
30
µS Defined as the time between the
instant that the bandgap is
enabled and the moment that
the bandgap reference voltage
is stable.
*
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.
DS41120A-page 168
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
15.5.2 LOW VOLTAGE DETECT MODULE (LVD)
TABLE 15-8: LOW-VOLTAGE DETECT CHARACTERISTICS
VDD
VLVD
(LVDIF set by hardware)
LVDIF
(LVDIF can be cleared in software anytime during
the gray area)
TABLE 15-9: ELECTRICAL CHARACTERISTICS: LVD
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial and
0°C ≤ TA ≤ +70°C for commercial
Operating voltage VDD range as described in DC spec Section 15.1 and Section 15.2.
DC CHARACTERISTICS
Param
No.
Characteristic
Symbol
Min Typ† Max Units
Conditions
D420*
LVV = 0100
LVV = 0101
LVV = 0110
LVV = 0111
LVV = 1000
LVV = 1001
LVV = 1010
LVV = 1011
LVV = 1100
LVV = 1101
LVV = 1110
2.5
2.7
2.8
3.0
3.3
3.5
3.6
3.8
4.0
4.2
4.5
—
2.58 2.66
2.78 2.86
2.89 2.98
V
V
V
V
V
V
V
V
V
V
V
LVD Voltage
3.1
3.2
3.41 3.52
3.61 3.72
3.72 3.84
3.92 4.04
4.13 4.26
4.33 4.46
4.64 4.78
D422*
D423*
*
LVD Voltage Temperature
coefficient
LVD Voltage Supply Regulation
TCVOUT
15
50 ppm/°C
—
—
∆VLVD/
∆VDD
50 µV/V
These parameters are characterized but not tested.
Note 1: Production tested at Tamb = 25°C. Specifications over temperature limits ensured by characterization.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 169
PIC16C717/770/771
15.5.3 PROGRAMMABLE BROWN-OUT RESET
MODULE (PBOR)
TABLE 15-10: DC CHARACTERISTICS: PBOR
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial and
0°C ≤ TA ≤ +70°C for commercial
Operating voltage VDD range as described in DC spec Section 15.1 and Section 15.2.
DC CHARACTERISTICS
Param
Characteristic
Symbol
Min
Typ
Max
Units
Conditions
No.
2.5
2.58
2.66
D005*
BOR Voltage
BORV<1:0> = 11
BORV<1:0> = 10
BORV<1:0> = 01
BORV<1:0> = 00
2.7
4.2
4.5
—
2.78
4.33
4.64
15
2.86
4.46
4.78
50
VBOR
V
D006*
BOR Voltage Temperature coefficient
TCVOUT
∆VBOR/
∆VDD
ppm/°C
µV/V
—
—
D006A* BOR Voltage Supply Regulation
50
*
These parameters are characterized but not tested.
15.5.4 VREF MODULE
TABLE 15-11: DC CHARACTERISTICS: VREF
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 15.1
and Section 15.2.
Param
No.
Symbol
Characteristic
Output Voltage
Min
Typ†
Max
Units
Conditions
VDD ≥ 2.5V
VRL
VRH
2.0
4.0
—
2.048
4.096
15
2.1
4.2
50
V
V
D400
VDD ≥ 4.5V
D402*
TCVOUT Output Voltage Tempera-
ture coefficient
ppm/°C
—
—
—
—
—
—
—
—
1
D404*
D405*
*
IVREFSO External Load Source
5
-5
200
TBD
TBD
mA
mA
pF
IVREFSI
External Load Sink
External capacitor load
Load Regulation
CL
D406*
Isource = 0 mA to 5 mA
∆VOUT/
∆IOUT
mV/mA
1
Isink
= 0 mA to 5 mA
D407*
*
Supply Regulation
∆VOUT/
∆VDD
—
—
50
µV/V
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.
DS41120A-page 170
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
15.5.5 A/D CONVERTER MODULE
TABLE 15-12: PIC16C770/771 AND PIC16LC770/771 A/D CONVERTER CHARACTERISTICS:
Param
No.
Sym Characteristic
Min
Typ†
Max
Units
Conditions
A01
NR
Resolution
—
—
12 bits
bit Min. resolution for A/D is 1 mV,
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
A03
A04
EIL
Integral error
—
—
—
—
TBD
TBD
—
—
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
EDL
Differential error
No missing codes to 10 bits
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
A06
A07
EOFF
EGN
Offset error
Gain Error
—
—
—
—
TBD
TBD
—
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
LSb VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
(3)
A10
A20
—
Monotonicity
—
guaranteed
—
—
—
V
AVSS ≤ VAIN ≤ VREF+
VREF
Reference voltage
(VREF+ VREF-)
4.096
VDD +0.3V
Absolute minimum electrical spec to
ensure 12-bit accuracy.
A21
A22
VREF+ Reference V High
(AVDD or VREF+)
VREF-
AVSS
—
—
AVDD
V
V
Min. resolution for A/D is 1 mV
VREF-
Reference V Low
VREF+
Min. resolution for A/D is 1 mV
(AVSS or VREF-)
A25
A30
VAIN
ZAIN
Analog input voltage
VREFL
—
—
VREFH
V
Recommended
—
2.5
kΩ
impedance of analog
voltage source
A50
IREF
VREF input current
—
—
10
µA During VAIN acquisition.
(Note 2)
Based on differential of VHOLD to VAIN.
To charge CHOLD see Section 11.0.
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 input current is from External VREF+, or VREF-, or AVSS, or AVDD pin, whichever is selected as reference input.
3: The A/D conversion result never decreases with an increase in the input voltage and has no missing codes.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 171
PIC16C717/770/771
FIGURE 15-13: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION TIMING (NORMAL MODE)
BSF ADCON0, GO
1/2 TCY
134
131
Q4
130
A/D CLK
11
10
9
8
3
2
1
0
A/D DATA
ADRES
NEW_DATA
DONE
OLD_DATA
ADIF
GO
SAMPLING STOPPED
132
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 15-13: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units
Conditions
130*
TAD
A/D clock period
1.6
—
—
—
—
µs
µs
Tosc based, VREF ≥ 2.5V
3.0
Tosc based, VREF full range
130*
TAD
A/D Internal RC
oscillator period
ADCS<1:0> = 11 (RC mode)
3.0
2.0
—
6.0
4.0
9.0
6.0
—
µs
µs
At VDD = 2.5V
At VDD = 5.0V
131*
132*
TCNV
Conversion time (not
including
acquisition time)
(Note 1)
13TAD
TAD Set GO bit to new data in A/D result
register
TACQ
Acquisition Time
Note 2
5*
11.5
—
—
—
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 1LSb (i.e
1mV @ 4.096V) from the last sam-
pled voltage (as stated on CHOLD).
134*
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.
*
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: ADRES register may be read on the following TCY cycle.
2: See Section 11.6 for minimum conditions.
DS41120A-page 172
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 15-14: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION TIMING (SLEEP MODE)
BSF ADCON0, GO
134
131
Q4
130
A/D CLK
11
10
9
3
2
1
0
8
A/D DATA
ADRES
OLD_DATA
NEW_DATA
DONE
ADIF
GO
SAMPLING STOPPED
132
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 15-14: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units
Conditions
130*
TAD
A/D clock period
1.6
—
—
—
—
µs
µs
VREF ≥ 2.5V
TBD
VREF full range
130*
TAD
A/D Internal RC
oscillator period
ADCS<1:0> = 11 (RC mode)
3.0
2.0
—
6.0
4.0
9.0
6.0
—
µs
µs
—
At VDD = 3.0V
At VDD = 5.0V
131*
132*
TCNV
TACQ
Conversion time (not
including acquisition
time) (Note 1)
13TAD
Acquisition Time
Note 2
5*
11.5
—
—
—
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 1LSb (i.e
1mV @ 4.096V) from the last sam-
pled voltage (as stated on CHOLD).
134*
TGO
Q4 to A/D clock start
—
TOSC/2 + TCY
—
—
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.
*
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: ADRES register may be read on the following TCY cycle.
2: See Section 11.6 for minimum conditions.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 173
PIC16C717/770/771
TABLE 15-15: PIC16C717 AND PIC16LC717 A/D CONVERTER CHARACTERISTICS:
Param
No.
Sym Characteristic
Min
Typ†
Max
Units
Conditions
A01
NR
Resolution
—
—
10 bits
bit Min. resolution for A/D is 4.1 mV,
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
A03
A04
EIL
Integral error
—
—
—
—
TBD
TBD
—
—
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
EDL
Differential error
No missing codes to 10 bits
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
A06
A07
EOFF
EGN
Offset error
Gain Error
—
—
—
—
TBD
TBD
—
VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
LSb VREF+ = AVDD = 4.096V,
VREF- = AVSS = 0V,
VREF- ≤ VAIN ≤ VREF+
(3)
A10
A20
—
Monotonicity
—
guaranteed
—
—
—
V
AVSS ≤ VAIN ≤ VREF+
VREF
Reference voltage
(VREF+ VREF-)
4.096
VDD +0.3V
Absolute minimum electrical spec to
ensure 10-bit accuracy.
A21
A22
VREF+ Reference V High
(AVDD or VREF+)
VREF-
AVSS
—
—
AVDD
V
V
Min. resolution for A/D is 4.1 mV
VREF-
Reference V Low
VREF+
Min. resolution for A/D is 4.1 mV
(AVSS or VREF-)
A25
A30
VAIN
ZAIN
Analog input voltage
VREFL
—
—
VREFH
V
Recommended
—
2.5
kΩ
impedance of analog
voltage source
A50
IREF
VREF input current
—
—
10
µA During VAIN acquisition.
(Note 2)
Based on differential of VHOLD to VAIN.
To charge CHOLD see Section 11.0.
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 leakage current. The power down current spec includes any such
leakage from the A/D module.
2: VREF current is from External VREF+, or VREF-, or AVSS, or AVDD pin, whichever is selected as reference input.
3: The A/D conversion result never decreases with an increase in the input voltage and has no missing codes.
DS41120A-page 174
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
FIGURE 15-15: PIC16C717 A/D CONVERSION TIMING (NORMAL MODE)
BSF ADCON0, GO
134
1/2 TCY
131
Q4
130
A/D CLK
9
8
7
6
3
2
1
0
A/D DATA
NEW_DATA
DONE
OLD_DATA
ADRES
ADIF
GO
SAMPLING STOPPED
132
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 15-16: PIC16C717 AND PIC16LC717 A/D CONVERSION REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units
Conditions
130*
TAD
A/D clock period
1.6
—
—
—
—
µs
µs
Tosc based, VREF ≥ 2.5V
3.0
Tosc based, VREF full range
130*
TAD
A/D Internal RC
oscillator period
ADCS<1:0> = 11 (RC mode)
3.0
2.0
—
6.0
4.0
9.0
6.0
—
µs
µs
At VDD = 2.5V
At VDD = 5.0V
131*
132*
TCNV
Conversion time (not
including
acquisition time)
(Note 1)
11TAD
TAD Set GO bit to new data in A/D result
register
TACQ
Acquisition Time
Note 2
5*
11.5
—
—
—
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 1LSb (i.e
1mV @ 4.096V) from the last sam-
pled voltage (as stated on CHOLD).
134*
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.
*
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: ADRES register may be read on the following TCY cycle.
2: See Section 11.6 for minimum conditions.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 175
PIC16C717/770/771
FIGURE 15-16: PIC16C717 A/D CONVERSION TIMING (SLEEP MODE)
BSF ADCON0, GO
134
131
Q4
130
A/D CLK
9
8
7
3
2
1
0
6
A/D DATA
ADRES
NEW_DATA
DONE
OLD_DATA
ADIF
GO
SAMPLING STOPPED
132
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 15-17: PIC16C717 AND PIC16LC717 A/D CONVERSION REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ†
Max
Units
Conditions
130*
TAD
A/D clock period
1.6
—
—
—
—
µs
µs
VREF ≥ 2.5V
TBD
VREF full range
130*
TAD
A/D Internal RC
oscillator period
ADCS<1:0> = 11 (RC mode)
3.0
2.0
—
6.0
4.0
9.0
6.0
—
µs
µs
—
At VDD = 3.0V
At VDD = 5.0V
131*
132*
TCNV
TACQ
Conversion time (not
including acquisition
time) (Note 1)
11TAD
Acquisition Time
Note 2
5*
11.5
—
—
—
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 1LSb (i.e
1mV @ 4.096V) from the last sam-
pled voltage (as stated on CHOLD).
134*
TGO
Q4 to A/D clock start
—
TOSC/2 + TCY
—
—
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.
*
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: ADRES register may be read on the following TCY cycle.
2: See Section 11.6 for minimum conditions.
DS41120A-page 176
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
16.0 DC AND AC
CHARACTERISTICS GRAPHS
AND TABLES
The graphs and tables provided in this section are for
design guidance and are not tested.
In some graphs or tables, the data presented are out-
side specified operating range (i.e., outside specified
VDD range). This is for information only.
The data presented in this section is a statistical sum-
mary of data collected on units from different lots over
a period of time and matrix samples. ’Typical’ repre-
sents the mean of the distribution at 25°C. ’Max’ or ’min’
represents (mean + 3σ) or (mean - 3σ) respectively,
where σ is standard deviation, over the whole temper-
ature range.
Graphs and Tables not available at this time.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 177
PIC16C717/770/771
NOTES:
DS41120A-page 178
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
17.0 PACKAGING INFORMATION
17.1
Package Marking Information
18-Lead PDIP
Example
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
PIC16C717/P
9917017
18-Lead CERDIP Windowed
Example
XXXXXXXX
XXXXXXXX
YYWWNNN
PIC16C717/JW
9905017
18-Lead SOIC
Example
XXXXXXXXXXXX
XXXXXXXXXXXX
XXXXXXXXXXXX
PIC16C717/SO
YYWWNNN
9910017
Example
20-Lead PDIP
PIC16C770/P
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
9917017
Legend: MM...M Microchip part number information
XX...X Customer specific information*
YY
WW
NNN
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Note: 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.
*
Standard OTP marking consists of Microchip part number, year code, week code, facility code, mask
rev#, 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.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 179
PIC16C717/770/771
Package Marking Information (Cont’d)
20-Lead SSOP
Example
PIC16C770
XXXXXXXXXXX
XXXXXXXXXXX
20I/SS
YYWWNNN
9917017
20-Lead CERDIP Windowed
Example
PIC16C770/JW
9905017
XXXXXXXX
XXXXXXXX
YYWWNNN
20-Lead SOIC
Example
XXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXX
PIC16C771/SO
YYWWNNN
9910017
DS41120A-page 180
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
17.2
18-Lead Plastic Dual In-line (P) – 300 mil (PDIP)
E1
D
2
α
n
1
E
A2
A
L
c
A1
B1
β
p
B
eB
Units
INCHES*
NOM
MILLIMETERS
Dimension Limits
MIN
MAX
MIN
NOM
MAX
n
p
Number of Pins
Pitch
18
.100
.155
.130
18
2.54
3.94
3.30
Top to Seating Plane
A
.140
.170
3.56
4.32
Molded Package Thickness
Base to Seating Plane
Shoulder to Shoulder Width
Molded Package Width
Overall Length
A2
A1
E
.115
.015
.300
.240
.890
.125
.008
.045
.014
.310
5
.145
2.92
0.38
7.62
6.10
22.61
3.18
0.20
1.14
0.36
7.87
5
3.68
.313
.250
.898
.130
.012
.058
.018
.370
10
.325
.260
.905
.135
.015
.070
.022
.430
15
7.94
6.35
22.80
3.30
0.29
1.46
0.46
9.40
10
8.26
6.60
22.99
3.43
0.38
1.78
0.56
10.92
15
E1
D
Tip to Seating Plane
Lead Thickness
L
c
Upper Lead Width
B1
B
Lower Lead Width
Overall Row Spacing
Mold Draft Angle Top
Mold Draft Angle Bottom
*Controlling Parameter
Notes:
eB
α
β
5
10
15
5
10
15
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MS-001
Drawing No. C04-007
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 181
PIC16C717/770/771
17.3
18-Lead Ceramic Dual In-line with Window (JW) – 300 mil (CERDIP)
E1
D
W2
2
1
n
W1
E
A2
A
c
L
A1
B1
eB
p
B
Units
INCHES*
NOM
MILLIMETERS
Dimension Limits
MIN
MAX
MIN
NOM
18
MAX
n
p
Number of Pins
Pitch
18
.100
.183
.160
.023
.313
.290
.900
.138
.010
.055
.019
.385
.140
.200
2.54
Top to Seating Plane
Ceramic Package Height
Standoff
A
.170
.195
4.32
3.94
4.64
4.06
0.57
7.94
7.37
22.86
3.49
0.25
1.40
0.47
9.78
3.56
5.08
4.95
A2
A1
.155
.015
.300
.285
.880
.125
.008
.050
.016
.345
.130
.190
.165
.030
.325
.295
.920
.150
.012
.060
.021
.425
.150
.210
4.19
0.76
8.26
7.49
23.37
3.81
0.30
1.52
0.53
10.80
3.81
5.33
0.38
7.62
7.24
22.35
3.18
0.20
1.27
0.41
8.76
3.30
4.83
Shoulder to Shoulder Width
Ceramic Pkg. Width
Overall Length
E
E1
D
L
Tip to Seating Plane
Lead Thickness
c
Upper Lead Width
Lower Lead Width
Overall Row Spacing
Window Width
B1
B
eB
W1
W2
Window Length
*Controlling Parameter
JEDEC Equivalent: MO-036
Drawing No. C04-010
DS41120A-page 182
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
17.4
18-Lead Plastic Small Outline (SO) – Wide, 300 mil (SOIC)
E
p
E1
D
2
1
B
n
h
α
45°
c
A2
A
φ
β
L
A1
Units
INCHES*
NOM
MILLIMETERS
Dimension Limits
MIN
MAX
MIN
NOM
18
MAX
n
p
Number of Pins
Pitch
18
.050
.099
.091
.008
.407
.295
.454
.020
.033
4
1.27
Overall Height
A
.093
.104
2.36
2.24
2.50
2.31
0.20
10.34
7.49
11.53
0.50
0.84
4
2.64
2.39
0.30
10.67
7.59
11.73
0.74
1.27
8
Molded Package Thickness
Standoff
A2
A1
E
.088
.004
.394
.291
.446
.010
.016
0
.094
.012
.420
.299
.462
.029
.050
8
0.10
10.01
7.39
11.33
0.25
0.41
0
Overall Width
Molded Package Width
Overall Length
E1
D
Chamfer Distance
Foot Length
h
L
φ
Foot Angle
c
Lead Thickness
Lead Width
.009
.014
0
.011
.017
12
.012
.020
15
0.23
0.36
0
0.27
0.42
12
0.30
0.51
15
B
α
β
Mold Draft Angle Top
Mold Draft Angle Bottom
*Controlling Parameter
Notes:
0
12
15
0
12
15
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MS-013
Drawing No. C04-051
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 183
PIC16C717/770/771
17.5
20-Lead Plastic Dual In-line (P) – 300 mil (PDIP)
E1
D
2
α
n
1
E
A2
A
L
c
A1
β
B1
eB
p
B
Units
INCHES*
NOM
MILLIMETERS
Dimension Limits
MIN
MAX
MIN
NOM
20
MAX
n
p
Number of Pins
Pitch
20
.100
.155
.130
2.54
Top to Seating Plane
A
.140
.170
3.56
2.92
3.94
3.30
4.32
Molded Package Thickness
Base to Seating Plane
Shoulder to Shoulder Width
Molded Package Width
Overall Length
A2
A1
E
.115
.015
.295
.240
1.025
.120
.008
.055
.014
.310
5
.145
3.68
0.38
7.49
6.10
26.04
3.05
0.20
1.40
0.36
7.87
5
.310
.250
1.033
.130
.012
.060
.018
.370
10
.325
.260
1.040
.140
.015
.065
.022
.430
15
7.87
6.35
26.24
3.30
0.29
1.52
0.46
9.40
10
8.26
6.60
26.42
3.56
0.38
1.65
0.56
10.92
15
E1
D
Tip to Seating Plane
Lead Thickness
L
c
Upper Lead Width
B1
B
Lower Lead Width
Overall Row Spacing
Mold Draft Angle Top
eB
α
β
Mold Draft Angle Bottom
*Controlling Parameter
Notes:
5
10
15
5
10
15
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MS-001
Drawing No. C04-019
DS41120A-page 184
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
17.6
20-Lead Ceramic Dual In-line with Window (JW) – 300 mil (CERDIP)
DRAWING NOT AVAILABLE
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 185
PIC16C717/770/771
17.7
20-Lead Plastic Small Outline (SO) – Wide, 300 mi (SOIC)
E
E1
p
D
2
B
n
1
h
α
45°
c
A2
A
φ
β
A1
L
Units
INCHES*
NOM
MILLIMETERS
Dimension Limits
MIN
MAX
MIN
NOM
20
MAX
n
p
Number of Pins
Pitch
20
.050
.099
.091
.008
.407
.295
.504
.020
.033
4
1.27
Overall Height
A
.093
.088
.004
.394
.291
.496
.010
.016
0
.104
2.36
2.24
2.50
2.31
0.20
10.34
7.49
12.80
0.50
0.84
4
2.64
Molded Package Thickness
Standoff
A2
A1
E
.094
.012
.420
.299
.512
.029
.050
8
2.39
0.30
10.67
7.59
13.00
0.74
1.27
8
0.10
10.01
7.39
12.60
0.25
0.41
0
Overall Width
Molded Package Width
Overall Length
E1
D
Chamfer Distance
Foot Length
h
L
φ
Foot Angle
c
Lead Thickness
Lead Width
.009
.014
0
.011
.017
12
.013
.020
15
0.23
0.36
0
0.28
0.42
12
0.33
0.51
15
B
α
Mold Draft Angle Top
Mold Draft Angle Bottom
*Controlling Parameter
Notes:
β
0
12
15
0
12
15
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MS-013
Drawing No. C04-094
DS41120A-page 186
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
17.8
20-Lead Plastic Shrink Small Outline (SS) – 209 mil, 5.30 mm (SSOP)
E
E1
p
D
B
2
1
n
α
c
A2
A
φ
L
A1
β
Units
INCHES*
NOM
MILLIMETERS
Dimension Limits
MIN
MAX
MIN
NOM
20
MAX
n
p
Number of Pins
Pitch
20
.026
.073
.068
.006
.309
.207
.284
.030
.007
4
0.66
Overall Height
A
.068
.078
1.73
1.63
1.85
1.73
0.15
7.85
5.25
7.20
0.75
0.18
101.60
0.32
5
1.98
1.83
0.25
8.18
5.38
7.34
0.94
0.25
203.20
0.38
10
Molded Package Thickness
Standoff
A2
A1
E
.064
.002
.299
.201
.278
.022
.004
0
.072
.010
.322
.212
.289
.037
.010
8
0.05
7.59
5.11
7.06
0.56
0.10
0.00
0.25
0
Overall Width
Molded Package Width
Overall Length
E1
D
Foot Length
L
c
Lead Thickness
Foot Angle
φ
Lead Width
B
α
β
.010
0
.013
5
.015
10
Mold Draft Angle Top
Mold Draft Angle Bottom
0
5
10
0
5
10
*Controlling Parameter
Notes:
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MO-150
Drawing No. C04-072
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 187
PIC16C717/770/771
NOTES:
DS41120A-page 188
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
APPENDIX A: REVISION HISTORY
Version
Date
Revision Description
A
9/16/99
This is a new data sheet. However, the devices described in this data sheet are
the upgrades to the devices found in the PIC16C7X Data Sheet, DS30390E.
APPENDIX B: DEVICE DIFFERENCES
The differences between the devices in this data sheet
are listed in Table B-1.
TABLE B-1:
Difference
DEVICE DIFFERENCES
PIC16C717
PIC16C770
PIC16C771
Program Memory
A/D
2K
2K
4K
6 channels, 10 bits
Not available
6 channels, 12 bits
Available
6 channels, 12 bits
Available
Dedicated AVDD
and AVSS
Packages
18-pin PDIP, 18-pin windowed
CERDIP, 18-pin SOIC,
20-pin SSOP
20-pin PDIP, 20-pin windowed
CERDIP, 20-pin SOIC,
20-pin SSOP
20-pin PDIP, 20-pin windowed
CERDIP, 20-pin SOIC,
20-pin SSOP
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 189
PIC16C717/770/771
NOTES:
DS41120A-page 190
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
INDEX
A
C
Capture (CCP Module) ....................................................... 56
Block Diagram ............................................................ 56
CCP Pin Configuration ............................................... 56
CCPR1H:CCPR1L Registers ..................................... 56
Changing Between Capture Prescalers ..................... 56
Software Interrupt....................................................... 56
Timer1 Mode Selection............................................... 56
CCP1CON .......................................................................... 15
CCP2CON .......................................................................... 15
CCPR1H Register......................................................... 13, 15
CCPR1L Register ............................................................... 15
CCPR2H Register............................................................... 15
CCPR2L Register ............................................................... 15
CKE .................................................................................... 68
CKP .................................................................................... 69
Clock Polarity Select bit, CKP............................................. 69
Code Examples
Loading the SSPBUF register .................................... 72
Code Protection........................................................ 125, 139
Compare (CCP Module) ..................................................... 56
Block Diagram ............................................................ 57
CCP Pin Configuration ............................................... 56
CCPR1H:CCPR1L Registers ..................................... 56
Software Interrupt....................................................... 56
Special Event Trigger ........................................... 51, 57
Timer1 Mode Selection............................................... 56
Configuration Bits ............................................................. 125
A/D.................................................................................... 113
A/D Converter Enable (ADIE Bit)................................ 19
ADCON0 Register..................................................... 113
ADCON1 Register............................................. 113, 115
ADRES Register ....................................................... 113
Block Diagram........................................................... 117
Configuring Analog Port............................................ 116
Conversion time........................................................ 123
Conversions.............................................................. 119
converter characteristics................... 169, 170, 171, 174
Faster Conversion - Lower Resolution Tradeoff ....... 123
Internal Sampling Switch (Rss) Impedence.............. 121
Operation During Sleep ............................................ 124
Sampling Requirements............................................ 121
Sampling Time.......................................................... 121
Source Impedance.................................................... 121
Special Event Trigger (CCP)....................................... 57
A/D Conversion Clock....................................................... 118
ACK..................................................................................... 78
Acknowledge Data bit, AKD................................................ 70
Acknowledge Pulse............................................................. 78
Acknowledge Sequence Enable bit, AKE ........................... 70
Acknowledge Status bit, AKS ............................................. 70
ACKSTAT ........................................................................... 92
ADCON0 Register............................................................. 113
ADCON1 Register..................................................... 113, 115
ADRES.............................................................................. 113
ADRES Register ........................................... 13, 14, 113, 124
AKD..................................................................................... 70
AKE..................................................................................... 70
AKS..................................................................................... 70
Application Note AN578, "Use of the SSP Module in the I2C
Multi-Master Environment."................................................. 77
Architecture
D
D/A...................................................................................... 68
Data Memory ...................................................................... 11
Bank Select (RP<1:0> Bits).................................. 11, 16
General Purpose Registers ........................................ 11
Register File Map ....................................................... 12
Special Function Registers......................................... 13
Data/Address bit, D/A ......................................................... 68
DC Characteristics
PIC16C717/770/771................................................. 158
Development Support....................................................... 149
Device Differences............................................................ 189
Direct Addressing ............................................................... 25
PIC16C717/PIC16C717 Block Diagram ....................... 5
PIC16C770/771/PIC16C770/771 Block Diagram ......... 6
Assembler
MPASM Assembler................................................... 149
B
E
Banking, Data Memory ................................................. 11, 16
Baud Rate Generator.......................................................... 86
BF ..................................................................... 68, 78, 92, 95
Block Diagrams
Enhanced Capture/Compare/PWM (CCP)
CCP1
CCPR1H Register .............................................. 55
CCPR1L Register............................................... 55
Enable (CCP1IE Bit)........................................... 19
Timer Resources ........................................................ 56
Enhanced Capture/Compare/PWM (ECCP)....................... 55
External Power-on Reset Circuit....................................... 130
Baud Rate Generator.................................................. 86
2
I C Master Mode......................................................... 84
2
I C Module.................................................................. 77
RA3:RA0 and RA5 Port Pins .................... 28, 30, 31, 37
2
SSP (I C Mode) .......................................................... 77
SSP (SPI Mode).......................................................... 71
BOR. See Brown-out Reset
F
Firmware Instructions ....................................................... 141
Flowcharts
BRG .................................................................................... 86
Brown-out Reset (BOR).................................... 125, 131, 132
Buffer Full bit, BF ................................................................ 78
Buffer Full Status bit, BF ..................................................... 68
Bus Arbitration .................................................................. 103
Bus Collision Section ........................................................ 103
Bus Collision During a RESTART Condition..................... 106
Bus Collision During a Start Condition.............................. 104
Bus Collision During a Stop Condition .............................. 107
Acknowledge .............................................................. 99
Master Receiver ......................................................... 96
Master Transmit.......................................................... 93
Restart Condition........................................................ 90
Start Condition............................................................ 88
Stop Condition.......................................................... 101
FSR Register.......................................................... 13, 14, 15
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 191
PIC16C717/770/771
Indirect Addressing............................................................. 25
FSR Register.............................................................. 11
Instruction Format............................................................. 141
Instruction Set................................................................... 141
ADDLW..................................................................... 143
ADDWF..................................................................... 143
ANDLW..................................................................... 143
ANDWF..................................................................... 143
BCF .......................................................................... 143
BSF........................................................................... 143
BTFSC...................................................................... 144
BTFSS ...................................................................... 144
CALL......................................................................... 144
CLRF ........................................................................ 144
CLRW ....................................................................... 144
CLRWDT .................................................................. 144
COMF ....................................................................... 145
DECF........................................................................ 145
DECFSZ ................................................................... 145
GOTO ....................................................................... 145
INCF ......................................................................... 145
INCFSZ..................................................................... 145
IORLW...................................................................... 146
IORWF...................................................................... 146
MOVF ....................................................................... 146
MOVLW .................................................................... 146
MOVWF.................................................................... 146
NOP.......................................................................... 146
RETFIE..................................................................... 147
RETLW ..................................................................... 147
RETURN................................................................... 147
RLF........................................................................... 147
RRF .......................................................................... 147
SLEEP ...................................................................... 147
SUBLW..................................................................... 148
SUBWF..................................................................... 148
SWAPF..................................................................... 148
XORLW .................................................................... 148
XORWF .................................................................... 148
Summary Table ........................................................ 142
INTCON.............................................................................. 15
INTCON Register................................................................ 18
GIE Bit ........................................................................ 18
INTE Bit ...................................................................... 18
INTF Bit ...................................................................... 18
PEIE Bit ...................................................................... 18
RBIE Bit ...................................................................... 18
RBIF Bit ................................................................ 18, 35
T0IE Bit....................................................................... 18
T0IF Bit....................................................................... 18
G
GCE ....................................................................................70
General Call Address Sequence.........................................83
General Call Address Support ............................................83
General Call Enable bit, GCE .............................................70
I
I/O Ports..............................................................................27
2
I C.......................................................................................77
2
I C Master Mode Receiver Flowchart .................................96
2
I C Master Mode Reception................................................95
2
I C Master Mode Restart Condition ....................................89
2
I C Mode Selection .............................................................77
2
I C Module
Acknowledge Flowchart..............................................99
Acknowledge Sequence timing...................................98
Addressing ..................................................................78
Baud Rate Generator..................................................86
Block Diagram.............................................................84
BRG Block Diagram....................................................86
BRG Reset due to SDA Collision..............................105
BRG Timing ................................................................86
Bus Arbitration ..........................................................103
Bus Collision .............................................................103
Acknowledge.....................................................103
Restart Condition ..............................................106
Restart Condition Timing (Case1).....................106
Restart Condition Timing (Case2).....................106
Start Condition ..................................................104
Start Condition Timing .............................. 104, 105
Stop Condition ..................................................107
Stop Condition Timing (Case1).........................107
Stop Condition Timing (Case2).........................107
Transmit Timing ................................................103
Bus Collision timing...................................................103
Clock Arbitration........................................................102
Clock Arbitration Timing (Master Transmit)...............102
Conditions to not give ACK Pulse ...............................78
General Call Address Support ....................................83
Master Mode...............................................................84
Master Mode 7-bit Reception timing ...........................97
Master Mode Operation ..............................................85
Master Mode Start Condition ......................................87
Master Mode Transmission.........................................92
Master Mode Transmit Sequence...............................85
Master Transmit Flowchart .........................................93
Multi-Master Communication ....................................103
Multi-master Mode ......................................................85
Operation ....................................................................77
Repeat Start Condition timing .....................................89
Restart Condition Flowchart........................................90
Slave Mode.................................................................78
Slave Reception..........................................................79
Slave Transmission.....................................................79
SSPBUF......................................................................78
Start Condition Flowchart............................................88
Stop Condition Flowchart..........................................101
Stop Condition Receive or Transmit timing...............100
Stop Condition timing................................................100
Waveforms for 7-bit Reception ...................................80
Waveforms for 7-bit Transmission ..............................80
2
Inter-Integrated Circuit (I C) ............................................... 67
internal sampling switch (Rss) impedence ....................... 121
Interrupt Sources ...................................................... 125, 135
Block Diagram .......................................................... 135
Capture Complete (CCP)............................................ 56
Compare Complete (CCP).......................................... 56
RB0/INT Pin, External............................................... 136
TMR0 Overflow................................................... 48, 136
TMR1 Overflow..................................................... 49, 51
TMR2 to PR2 Match ................................................... 54
TMR2 to PR2 Match (PWM)................................. 53, 58
Interrupts
2
I C Module Address Register, SSPADD.............................78
2
I C Slave Mode...................................................................78
Synchronous Serial Port Interrupt............................... 20
Interrupts, Context Saving During..................................... 136
ID Locations ..............................................................125, 139
In-Circuit Serial Programming (ICSP) ....................... 125, 139
INDF....................................................................................15
INDF Register ............................................................... 13, 14
DS41120A-page 192
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Interrupts, Enable Bits
PICDEM-1 Low-Cost PICmicro Demo Board ................... 151
PICDEM-2 Low-Cost PIC16CXX Demo Board................. 151
PICDEM-3 Low-Cost PIC16CXXX Demo Board .............. 151
PICSTART Plus Entry Level Development System.......... 151
PIE1 Register ..................................................................... 19
ADIE Bit...................................................................... 19
CCP1IE Bit ................................................................. 19
PSPIE Bit.................................................................... 19
RCIE Bit...................................................................... 19
SSPIE Bit.................................................................... 19
TMR1IE Bit ................................................................. 19
TMR2IE Bit ................................................................. 19
PIE2 Register ..................................................................... 21
Pinout Descriptions
PIC16C717................................................................... 9
PIC16C770................................................................... 7
PIC16C770/771............................................................ 7
PIC16C771................................................................... 7
PIR1 Register ..................................................................... 20
PIR2 Register ..................................................................... 22
PMCON1 ............................................................................ 43
Pointer, FSR ....................................................................... 25
POR. See Power-on Reset
A/D Converter Enable (ADIE Bit)................................ 19
CCP1 Enable (CCP1IE Bit)................................... 19, 56
Global Interrupt Enable (GIE Bit) ........................ 18, 135
Interrupt on Change (RB7:RB4) Enable
(RBIE Bit)............................................................ 18, 136
Peripheral Interrupt Enable (PEIE Bit) ........................ 18
PSP Read/Write Enable (PSPIE Bit) .......................... 19
RB0/INT Enable (INTE Bit) ......................................... 18
SSP Enable (SSPIE Bit) ............................................. 19
TMR0 Overflow Enable (T0IE Bit)............................... 18
TMR1 Overflow Enable (TMR1IE Bit)......................... 19
TMR2 to PR2 Match Enable (TMR2IE Bit) ................. 19
USART Receive Enable (RCIE Bit) ............................ 19
Interrupts, Flag Bits
CCP1 Flag (CCP1IF Bit)............................................. 56
Interrupt on Change (RB7:RB4) Flag
(RBIF Bit) ...................................................... 18, 35, 136
RB0/INT Flag (INTF Bit).............................................. 18
TMR0 Overflow Flag (T0IF Bit)........................... 18, 136
INTRC Mode ..................................................................... 128
K
KeeLoq Evaluation and Programming Tools.................. 152
PORTA ............................................................................... 15
Initialization................................................................. 28
PORTA Register......................................................... 27
TRISA Register........................................................... 27
PORTA Register......................................................... 13, 124
PORTB ............................................................................... 15
Initialization................................................................. 35
PORTB Register......................................................... 35
Pull-up Enable (RBPU Bit).......................................... 17
RB0/INT Edge Select (INTEDG Bit) ........................... 17
RB0/INT Pin, External .............................................. 136
RB7:RB4 Interrupt on Change.................................. 136
RB7:RB4 Interrupt on Change Enable
(RBIE Bit)........................................................... 18, 136
RB7:RB4 Interrupt on Change Flag
(RBIF Bit)...................................................... 18, 35, 136
TRISB Register........................................................... 35
PORTB Register......................................................... 13, 124
Postscaler, Timer2
Select (TOUTPS Bits)................................................. 53
Postscaler, WDT................................................................. 47
Assignment (PSA Bit)........................................... 17, 47
Block Diagram ............................................................ 48
Rate Select (PS Bits)............................................ 17, 47
Switching Between Timer0 and WDT......................... 48
Power-on Reset (POR)..................... 125, 129, 130, 131, 132
Oscillator Start-up Timer (OST)........................ 125, 130
Power Control (PCON) Register............................... 131
Power-down (PD Bit).................................................. 16
Power-on Reset Circuit, External ............................. 130
Power-up Timer (PWRT).................................. 125, 130
Time-out (TO Bit)........................................................ 16
Time-out Sequence .................................................. 131
Time-out Sequence on Power-up..................... 133, 134
PR2 Register ...................................................................... 14
Prescaler, Capture.............................................................. 56
Prescaler, Timer0 ............................................................... 47
Assignment (PSA Bit)........................................... 17, 47
Block Diagram ............................................................ 48
Rate Select (PS Bits)............................................ 17, 47
Switching Between Timer0 and WDT......................... 48
Prescaler, Timer1 ............................................................... 50
Select (T1CKPS Bits) ................................................. 49
M
Master Clear (MCLR)
MCLR Reset, Normal Operation............... 129, 131, 132
MCLR Reset, SLEEP................................ 129, 131, 132
Memory Organization
Data Memory .............................................................. 11
Program Memory ........................................................ 11
MPLAB Integrated Development Environment Software .. 149
Multi-Master Communication ............................................ 103
Multi-Master Mode .............................................................. 85
O
OPCODE Field Descriptions............................................. 141
OPERATION....................................................................... 45
OPTION_REG Register ...................................................... 17
INTEDG Bit ................................................................. 17
PS Bits .................................................................. 17, 47
PSA Bit.................................................................. 17, 47
RBPU Bit..................................................................... 17
T0CS Bit................................................................ 17, 47
T0SE Bit................................................................ 17, 47
Oscillator Configuration..................................................... 126
CLKOUT ................................................................... 128
Dual Speed Operation for ER and INTRC Modes .... 128
EC............................................................. 126, 127, 131
ER..................................................................... 126, 131
ER Mode................................................................... 128
HS..................................................................... 126, 131
INTRC............................................................... 126, 131
LP...................................................................... 126, 131
XT ..................................................................... 126, 131
Oscillator, Timer1.......................................................... 49, 51
Oscillator, WDT................................................................. 137
P
P.......................................................................................... 68
Packaging ......................................................................... 179
Paging, Program Memory............................................. 11, 24
Parallel Slave Port (PSP)
Read/Write Enable (PSPIE Bit)................................... 19
PCL Register................................................................. 13, 14
PCLATH Register ................................................... 13, 14, 15
PCON Register ........................................................... 23, 131
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 193
PIC16C717/770/771
Prescaler, Timer2................................................................59
Select (T2CKPS Bits)..................................................53
PRO MATE II Universal Programmer.............................151
Program ..............................................................................43
Program Counter
SCL..................................................................................... 78
SDA .................................................................................... 78
SDI...................................................................................... 71
SDO.................................................................................... 71
SEEVAL Evaluation and Programming System............. 152
Serial Clock, SCK ............................................................... 71
Serial Clock, SCL................................................................ 78
Serial Data Address, SDA .................................................. 78
Serial Data In, SDI.............................................................. 71
Serial Data Out, SDO ......................................................... 71
Slave Select Synchronization ............................................. 74
Slave Select, SS................................................................. 71
SLEEP .............................................................. 125, 129, 138
SMP.................................................................................... 68
Software Simulator (MPLAB-SIM) .................................... 150
SPE..................................................................................... 70
Special Features of the CPU ............................................ 125
Special Function Registers................................................. 13
PIC16C717 ................................................................. 13
PIC16C717/770/771 ................................................... 13
PIC16C770 ................................................................. 13
PIC16C771 ................................................................. 13
Speed, Operating.................................................................. 1
SPI
PCL Register...............................................................24
PCLATH Register ............................................... 24, 136
Reset Conditions.......................................................131
Program Memory ................................................................11
Interrupt Vector ...........................................................11
Paging................................................................... 11, 24
Program Memory Map ................................................11
Reset Vector ...............................................................11
Program Verification..........................................................139
Programmable Brown-out Reset (PBOR) ................. 129, 130
Programming, Device Instructions ....................................141
PWM (CCP Module)............................................................58
Block Diagram.............................................................58
CCPR1H:CCPR1L Registers......................................58
Duty Cycle...................................................................59
Output Diagram...........................................................59
Period..........................................................................58
TMR2 to PR2 Match .............................................53, 58
TMR2 to PR2 Match Enable (TMR2IE Bit) .................19
Master Mode............................................................... 73
Serial Clock................................................................. 71
Serial Data In.............................................................. 71
Serial Data Out ........................................................... 71
Serial Peripheral Interface (SPI)................................. 67
Slave Select................................................................ 71
SPI Clock.................................................................... 73
SPI Mode.................................................................... 71
SPI Clock Edge Select, CKE .............................................. 68
SPI Data Input Sample Phase Select, SMP ....................... 68
SPI Master/Slave Connection............................................. 72
SPI Module
Q
Q-Clock ...............................................................................59
R
R/W .....................................................................................68
R/W bit ................................................................................78
R/W bit ................................................................................79
RAM. See Data Memory
RCE,Receive Enable bit, RCE............................................70
RCREG ...............................................................................15
RCSTA Register..................................................................15
Read/Write bit, R/W ............................................................68
READING............................................................................45
Receive Overflow Indicator bit, SSPOV..............................69
Register File........................................................................11
Register File Map................................................................12
Registers
FSR Summary ............................................................15
INDF Summary ...........................................................15
INTCON Summary......................................................15
PCL Summary.............................................................15
PCLATH Summary .....................................................15
PORTB Summary .......................................................15
SSPSTAT....................................................................68
STATUS Summary .....................................................15
TMR0 Summary..........................................................15
TRISB Summary.........................................................15
Reset......................................................................... 125, 129
Block Diagram...........................................................129
Brown-out Reset (BOR). See Brown-out Reset (BOR)
MCLR Reset. See MCLR
Master/Slave Connection............................................ 72
Slave Mode................................................................. 74
Slave Select Synchronization ..................................... 74
Slave Synch Timnig.................................................... 74
SS....................................................................................... 71
SSP..................................................................................... 67
Block Diagram (SPI Mode) ......................................... 71
Enable (SSPIE Bit) ..................................................... 19
SPI Mode.................................................................... 71
SSPADD..................................................................... 78
SSPBUF ............................................................... 73, 78
SSPCON1 .................................................................. 69
SSPCON2 .................................................................. 70
SSPSR ................................................................. 73, 78
SSPSTAT ............................................................. 68, 77
TMR2 Output for Clock Shift................................. 53, 54
2
SSP I C
2
SSP I C Operation ..................................................... 77
SSP Module
Power-on Reset (POR). See Power-on Reset (POR)
Reset Conditions for All Registers ............................132
Reset Conditions for PCON Register........................131
Reset Conditions for Program Counter.....................131
Reset Conditions for STATUS Register....................131
Restart Condition Enabled bit, RSE....................................70
Revision History ................................................................189
RSE.....................................................................................70
SPI Master Mode........................................................ 73
SPI Master./Slave Connection.................................... 72
SPI Slave Mode.......................................................... 74
SSPCON1 Register.................................................... 77
SSP Overflow Detect bit, SSPOV....................................... 78
SSPADD Register............................................................... 14
SSPBUF ....................................................................... 15, 78
SSPBUF Register............................................................... 13
SSPCON Register .............................................................. 13
SSPCON1..................................................................... 69, 77
SSPCON2........................................................................... 70
SSPEN................................................................................ 69
S
SAE.....................................................................................70
SCK.....................................................................................71
DS41120A-page 194
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
SSPIF............................................................................ 20, 79
SSPM3:SSPM0................................................................... 69
SSPOV.................................................................... 69, 78, 95
SSPSTAT...................................................................... 68, 77
SSPSTAT Register ............................................................. 14
Stack................................................................................... 24
Start bit (S).......................................................................... 68
Start Condition Enabled bit, SAE ........................................ 70
STATUS Register ....................................................... 16, 136
C Bit ............................................................................ 16
DC Bit.......................................................................... 16
IRP Bit......................................................................... 16
PD Bit.......................................................................... 16
RP1:RP0 Bits.............................................................. 16
TO Bit.......................................................................... 16
Z Bit............................................................................. 16
Status Register ................................................................... 16
Stop bit (P) .......................................................................... 68
Stop Condition Enable bit ................................................... 70
Synchronous Serial Port ..................................................... 67
Synchronous Serial Port Enable bit, SSPEN ...................... 69
Synchronous Serial Port Interrupt....................................... 20
Synchronous Serial Port Mode Select bits,
Timing Diagrams
Acknowledge Sequence Timing ................................. 98
Baud Rate Generator with Clock Arbitration............... 86
BRG Reset Due to SDA Collision............................. 105
Brown-out Reset....................................................... 164
Bus Collision
Start Condition Timing...................................... 104
Bus Collision During a Restart Condition (Case 1)... 106
Bus Collision During a Restart Condition (Case2).... 106
Bus Collision During a Start Condition (SCL = 0)..... 105
Bus Collision During a Stop Condition...................... 107
Bus Collision for Transmit and Acknowledge ........... 103
Capture/Compare/PWM ........................................... 166
CLKOUT and I/O ...................................................... 162
External Clock Timing............................................... 162
2
I C Master Mode First Start bit timing ........................ 87
2
I C Master Mode Reception timing............................. 97
2
I C Master Mode Transmission timing ....................... 94
Master Mode Transmit Clock Arbitration .................. 102
Power-up Timer........................................................ 164
Repeat Start Condition ............................................... 89
Reset ........................................................................ 164
Slave Synchronization................................................ 74
Start-up Timer........................................................... 164
Stop Condition Receive or Transmit......................... 100
Time-out Sequence on Power-up..................... 133, 134
Timer0 ...................................................................... 165
Timer1 ...................................................................... 165
Wake-up from SLEEP via Interrupt .......................... 139
Watchdog Timer ....................................................... 164
TMR0.................................................................................. 15
TMR0 Register.................................................................... 13
TMR1H ............................................................................... 15
TMR1H Register................................................................. 13
TMR1L................................................................................ 15
TMR1L Register.................................................................. 13
TMR2.................................................................................. 15
TMR2 Register.................................................................... 13
TRISA Register........................................................... 14, 124
TRISB Register........................................................... 14, 124
TXREG ............................................................................... 15
SSPM<3:0>......................................................................... 69
T
T1CON................................................................................ 15
T1CON Register ........................................................... 15, 49
T1CKPS Bits............................................................... 49
T1OSCEN Bit.............................................................. 49
T1SYNC Bit................................................................. 49
TMR1CS Bit................................................................ 49
TMR1ON Bit................................................................ 49
T2CON Register ........................................................... 15, 53
T2CKPS Bits............................................................... 53
TMR2ON Bit................................................................ 53
TOUTPS Bits .............................................................. 53
Timer0................................................................................. 47
Block Diagram............................................................. 47
Clock Source Edge Select (T0SE Bit)................... 17, 47
Clock Source Select (T0CS Bit)............................ 17, 47
Overflow Enable (T0IE Bit) ......................................... 18
Overflow Flag (T0IF Bit)...................................... 18, 136
Overflow Interrupt ............................................... 48, 136
Timer1................................................................................. 49
Block Diagram............................................................. 50
Capacitor Selection..................................................... 51
Clock Source Select (TMR1CS Bit) ............................ 49
External Clock Input Sync (T1SYNC Bit).................... 49
Module On/Off (TMR1ON Bit)..................................... 49
Oscillator............................................................... 49, 51
Oscillator Enable (T1OSCEN Bit) ............................... 49
Overflow Enable (TMR1IE Bit).................................... 19
Overflow Interrupt ................................................. 49, 51
Special Event Trigger (CCP)................................. 51, 57
T1CON Register ......................................................... 49
TMR1H Register ......................................................... 49
TMR1L Register.......................................................... 49
Timer2
U
Update Address, UA........................................................... 68
USART
Receive Enable (RCIE Bit) ......................................... 19
W
W Register........................................................................ 136
Wake-up from SLEEP............................................... 125, 138
Interrupts .......................................................... 131, 132
MCLR Reset............................................................. 132
Timing Diagram ........................................................ 139
WDT Reset............................................................... 132
Watchdog Timer (WDT)............................................ 125, 137
Block Diagram .......................................................... 137
Enable (WDTE Bit) ................................................... 137
Programming Considerations................................... 137
RC Oscillator ............................................................ 137
Time-out Period........................................................ 137
WDT Reset, Normal Operation................. 129, 131, 132
WDT Reset, SLEEP ......................................... 131, 132
Waveform for General Call Address Sequence.................. 83
WCOL................................................. 69, 87, 92, 95, 98, 100
WCOL Status Flag.............................................................. 87
Write Collision Detect bit, WCOL........................................ 69
WWW, On-Line Support ....................................................... 3
Block Diagram............................................................. 54
PR2 Register......................................................... 53, 58
SSP Clock Shift..................................................... 53, 54
T2CON Register ......................................................... 53
TMR2 Register............................................................ 53
TMR2 to PR2 Match Enable (TMR2IE Bit) ................. 19
TMR2 to PR2 Match Interrupt......................... 53, 54, 58
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 195
PIC16C717/770/771
NOTES:
DS41120A-page 196
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
Systems Information and Upgrade Hot Line
ON-LINE SUPPORT
The Systems Information and Upgrade Line provides
system users a listing of the latest versions of all of
Microchip’s development systems software products.
Plus, this line provides information on how customers
can receive any currently available upgrade kits.The
Hot Line Numbers are:
Microchip provides on-line support on the Microchip
World Wide Web (WWW) site.
The web site is used by Microchip as a means to make
files and information easily available to customers. To
view the site, the user must have access to the Internet
and a web browser, such as Netscape or Microsoft
Explorer. Files are also available for FTP download
from our FTP site.
1-800-755-2345 for U.S. and most of Canada, and
1-480-786-7302 for the rest of the world.
981103
ConnectingtotheMicrochipInternetWebSite
The Microchip web site is available by using your
favorite Internet browser to attach to:
www.microchip.com
The file transfer site is available by using an FTP ser-
vice to connect to:
ftp://ftp.microchip.com
The web site and file transfer site provide a variety of
services. Users may download files for the latest
Development Tools, Data Sheets, Application Notes,
User’s Guides, Articles and Sample Programs. A vari-
ety of Microchip specific business information is also
available, including listings of Microchip sales offices,
distributors and factory representatives. Other data
available for consideration is:
Trademarks: The Microchip name, logo, PIC, PICmicro,
PICSTART, PICMASTER and PRO MATE are registered
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries. FlexROM, MPLAB and fuzzy-
LAB are trademarks and SQTP is a service mark of Micro-
chip in the U.S.A.
• Latest Microchip Press Releases
• Technical Support Section with Frequently Asked
Questions
• Design Tips
• Device Errata
All other trademarks mentioned herein are the property of
their respective companies.
• Job Postings
• Microchip Consultant Program Member Listing
• Links to other useful web sites related to
Microchip Products
• Conferences for products, Development Sys-
tems, technical information and more
• Listing of seminars and events
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page197
PIC16C717/770/771
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip prod-
uct. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation
can better serve you, please FAX your comments to the Technical Publications Manager at (480) 786-7578.
Please list the following information, and use this outline to provide us with your comments about this Data Sheet.
To:
Technical Publications Manager
Reader Response
Total Pages Sent
RE:
From:
Name
Company
Address
City / State / ZIP / Country
Telephone: (_______) _________ - _________
FAX: (______) _________ - _________
Application (optional):
Would you like a reply?
Y
N
Literature Number:
DS41120A
Device:
PIC16C717/770/771
Questions:
1. What are the best features of this document?
2. How does this document meet your hardware and software development needs?
3. Do you find the organization of this data sheet easy to follow? If not, why?
4. What additions to the data sheet do you think would enhance the structure and subject?
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?
DS41120A-page198
Advanced Information
1999 Microchip Technology Inc.
PIC16C717/770/771
PIC16C717/770/771 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.
X /XX XXX
-
Pattern:
QTP, SQTP, Code or Special Requirements
a) PIC16C771/P Commercial
Temp., PDIP Package,
normal VDD limits.
Package:
JW
SO
P
=
=
=
=
Windowed CERDIP
SOIC
PDIP
SSOP
SS
Temperature
Range:
-
I
=
=
0°C to +70°C
-40°C to +85°C
Device
PIC16C771 : VDD range 4.0V to 5.5V
PIC16C771T :VDD range 4.0V to 5.5V (Tape/Reel)
PIC16LC771 : VDD range 2.5V to 5.5V
PIC16LC771T:VDD range 2.5V to 5.5V (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
Data Sheets
Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recom-
mended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following:
1. Your local Microchip sales office
2. The Microchip Corporate Literature Center U.S. FAX: (480) 786-7277
3. The Microchip Worldwide Site (www.microchip.com)
Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using.
New Customer Notification System
Register on our web site (www.microchip.com/cn) to receive the most current information on our products.
1999 Microchip Technology Inc.
Advanced Information
DS41120A-page 199
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.
相关型号：
©2020 ICPDF网 联系我们和版权申明