AT94K10AL-25AJJ_技术文档

Features

• Monolithic Field Programmable System Level Integrated Circuit (FPSLIC^®)

– AT40K SRAM-based FPGA with Embedded High-performance RISC AVR^®Core,

Extensive Data and Instruction SRAM and JTAG ICE

• 5,000 to 40,000 Gates of Patented SRAM-based AT40K FPGA with FreeRAM^™

– 2 - 18.4 Kbits of Distributed Single/Dual Port FPGA User SRAM

– High-performance DSP Optimized FPGA Core Cell

– Dynamically Reconfigurable In-System – FPGA Configuration Access Available

On-chip from AVR Microcontroller Core to Support Cache Logic^®Designs

– Very Low Static and Dynamic Power Consumption – Ideal for Portable and

Handheld Applications

• Patented AVR Enhanced RISC Architecture

5K - 40K Gates

of AT40K FPGA

with 8-bit

Microcontroller,

up to 36K Bytes

of SRAM and

On-chip

– 120+ Powerful Instructions – Most Single Clock Cycle Execution

– High-performance Hardware Multiplier for DSP-based Systems

– Approaching 1 MIPS per MHz Performance

– C Code Optimized Architecture with 32 x 8 General-purpose Internal Registers

– Low-power Idle, Power-save and Power-down Modes

– 100 µA Standby and Typical 2-3 mA per MHz Active

• Up to 36 Kbytes of Dynamically Allocated Instruction and Data SRAM

– Up to 16 Kbytes x 16 Internal 15 ns Instructions SRAM

– Up to 16 Kbytes x 8 Internal 15 ns Data SRAM

• JTAG (IEEE std. 1149.1 Compliant) Interface

– Extensive On-chip Debug Support

– Limited Boundary-scan Capabilities According to the JTAG Standard (AVR Ports)

• AVR Fixed Peripherals

JTAG ICE

– Industry-standard 2-wire Serial Interface

– Two Programmable Serial UARTs

– Two 8-bit Timer/Counters with Separate Prescaler and PWM

– One 16-bit Timer/Counter with Separate Prescaler, Compare, Capture

Modes and Dual 8-, 9- or 10-bit PWM

AT94KAL Series

Field

Programmable

System Level

Integrated

Circuit

• Support for FPGA Custom Peripherals

– AVR Peripheral Control – 16 Decoded AVR Address Lines Directly Accessible

to FPGA

– FPGA Macro Library of Custom Peripherals

• 16 FPGA Supplied Internal Interrupts to AVR

• Up to Four External Interrupts to AVR

• 8 Global FPGA Clocks

– Two FPGA Clocks Driven from AVR Logic

– FPGA Global Clock Access Available from FPGA Core

• Multiple Oscillator Circuits

– Programmable Watchdog Timer with On-chip Oscillator

– Oscillator to AVR Internal Clock Circuit

– Software-selectable Clock Frequency

– Oscillator to Timer/Counter for Real-time Clock

• V_CC: 3.0V - 3.6V

• 3.3V 33 MHz PCI-compliant FPGA I/O

– 20 mA Sink/Source High-performance I/O Structures

– All FPGA I/O Individually Programmable

• High-performance, Low-power 0.35µ CMOS Five-layer Metal Process

• State-of-the-art Integrated PC-based Software Suite including Co-verification

• 5V I/O Tolerant

1138H–FPSLI–6/05

1. Description

The AT94KAL Series FPSLIC family shown in Table 1-1 is a combination of the popular Atmel

AT40K Series SRAM FPGAs and the high-performance Atmel AVR 8-bit RISC microcontroller

with standard peripherals. Extensive data and instruction SRAM as well as device control and

management logic are included on this monolithic device, fabricated on Atmel’s 0.35µ five-layer

metal CMOS process.

The AT40K FPGA core is a fully 3.3V PCI-compliant, SRAM-based FPGA with distributed

10 ns programmable synchronous/asynchronous, dual-port/single-port SRAM, 8 global clocks,

Cache Logic ability (partially or fully reconfigurable without loss of data) and 5,000 to 40,000

usable gates.

Table 1-1.

Device

The AT94K Series Characteristics

AT94K05AL

AT94K10AL

10K

AT94K40AL

40K

FPGA Gates

5K

FPGA Core Cells

256

2048

436

96

576

2304

FPGA SRAM Bits

4096

846

18432

2862

FPGA Registers (Total)

Maximum FPGA User I/O

116

120

AVR Programmable I/O

Lines

8

16

20 Kbytes - 32

Kbytes

20 Kbytes - 32

Kbytes

Program SRAM

4 Kbytes - 16 Kbytes

Data SRAM

4 Kbytes - 16 Kbytes

4 Kbytes- 16 Kbytes

4 Kbytes - 16 Kbytes

Hardware Multiplier (8-bit)

2-wire Serial Interface

UARTs

Yes

2

Yes

2

Yes

2

Watchdog Timer

Timer/Counters

Real-time Clock

JTAG ICE

Yes

3

Yes

3

Yes

3

Yes

Yes⁽¹⁾

Yes

Yes⁽¹⁾

Yes

Yes⁽¹⁾

Typical AVR

throughput

@ 25

MHz

19 MIPS

Operating

Voltage⁽²⁾

AL

3.0 - 3.6V⁽²⁾

Notes: 1. FPSLIC parts with JTAG ICE support can be identified by the letter “J” after the device date

code, e.g., 4201 (no ICE support) and 4201J (with ICE support), see Figure 1-1.

2. FPSLIC devices should be laid out during PCB design to support a split power supply. Please

refer to the “Designing in Split Power Supply Support for AT94KAL and AT94SAL Devices”

application note, available on the Atmel web site at

http://www.atmel.com/atmel/acrobat/doc2308.pdf.

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AT94KAL Series FPSLIC

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AT94KAL Series FPSLIC

Figure 1-1. FPSLIC Device Date Code with JTAG ICE Support

®

AT94K40AL-25DQC

0H1230

4201J

Date Code

"J" indicates JTAG ICE support

The AT94K series architecture is shown in Figure 1-2.

Figure 1-2. AT94K Series Architecture

PROGRAMMABLE I/O

5 - 40K Gates FPGA

Up to 16

Addr Decoder

Up to 16K x 16

Program

SRAM Memory

4 Interrupt Lines

I/O

2-wire Serial

Unit

I/O

with

Multiply

Two 8-bit

Timer/Counters

Up to

16K x 8

Data

JTAG ICE

SRAM

16 Prog. I/O

Lines

I/O

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1138H–FPSLI–6/05

The embedded AVR core achieves throughputs approaching 1 MIPS per MHz by executing

powerful instructions in a single-clock cycle, and allows system designers to optimize power

consumption versus processing speed. The AVR core is based on an enhanced RISC architec-

ture that combines a rich instruction set with 32 general-purpose working registers. All 32

registers are directly connected to the Arithmetic Logic Unit (ALU), allowing two independent

registers to be accessed in one single instruction executed in one clock cycle. The resulting

architecture is more code-efficient while achieving throughputs up to ten times faster than con-

ventional CISC microcontrollers at the same clock frequency. The AVR executes out of on-chip

SRAM. Both the FPGA configuration SRAM and the AVR instruction code SRAM can be auto-

matically loaded at system power-up using Atmel’s In-System Programmable (ISP) AT17 Series

EEPROM Configuration Memories or ATFS FPSLIC Support Devices.

State-of-the-art FPSLIC design tools, System Designer, were developed in conjunction with the

FPSLIC architecture to help reduce overall time-to-market by integrating microcontroller devel-

opment and debug, FPGA development and Place and Route, and complete system

co-verification in one easy-to-use software tool.

Table 1-2.

FPSLIC Device

AT94K05

ATFS FPSLIC Support Devices

FPSLIC Support Device

ATFS05

Configuration Data

226520 Bits

Spare Memory

35624 Bits

AT94K10

AT94K40

ATFS10

430488 Bits

93800 Bits

ATFS40

815382 Bits

233194 Bits

2. FPGA Core

The AT40K core can be used for high-performance designs, by implementing a variety of com-

pute-intensive arithmetic functions. These include adaptive finite impulse response (FIR) filters,

fast Fourier transforms (FFT), convolvers, interpolators, and discrete-cosine transforms (DCT)

that are required for video compression and decompression, encryption, convolution and other

multimedia applications.

2.1

2.2

Fast, Flexible and Efficient SRAM

The AT40K core offers a patented distributed 10 ns SRAM capability where the RAM can be

used without losing logic resources. Multiple independent, synchronous or asynchronous, dual-

port or single-port RAM functions (FIFO, scratch pad, etc.) can be created using Atmel’s macro

generator tool.

Fast, Efficient Array and Vector Multipliers

The AT40K cores patented 8-sided core cell with direct horizontal, vertical and diagonal cell-to-

cell connections implements ultra-fast array multipliers without using any busing resources. The

AT40K core’s Cache Logic capability enables a large number of design coefficients and vari-

ables to be implemented in a very small amount of silicon, enabling vast improvement in system

speed.

2.3

Cache Logic Design

The AT40K FPGA core is capable of implementing Cache Logic (dynamic full/partial logic recon-

figuration, without loss of data, on-the-fly) for building adaptive logic and systems. As new logic

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AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

functions are required, they can be loaded into the logic cache without losing the data already

there or disrupting the operation of the rest of the chip; replacing or complementing the active

logic. The AT40K FPGA core can act as a reconfigurable resource within the FPSLIC

environment.

2.4

Automatic Component Generators

The AT40K is capable of implementing user-defined, automatically generated, macros; speed

and functionality are unaffected by the macro orientation or density of the target device. This

enables the fastest, most predictable and efficient FPGA design approach and minimizes design

risk by reusing already proven functions. The Automatic Component Generators work seam-

lessly with industry-standard schematic and synthesis tools to create fast, efficient designs.

The patented AT40K architecture employs a symmetrical grid of small yet powerful cells con-

nected to a flexible busing network. Independently controlled clocks and resets govern every

column of four cells. The FPSLIC device is surrounded on three sides by programmable I/Os.

Core usable gate counts range from 5,000 to 40,000 gates and 436 to 2,864 registers. Pin loca-

tions are consistent throughout the FPSLIC family for easy design migration in the same

package footprint.

The Atmel AT40K FPGA core architecture was developed to provide the highest levels of perfor-

mance, functional density and design flexibility. The cells in the FPGA core array are small,

efficient and can implement any pair of Boolean functions of (the same) three inputs or any sin-

gle Boolean function of four inputs. The cell’s small size leads to arrays with large numbers of

cells. A simple, high-speed busing network provides fast, efficient communication over medium

and long distances.

2.5

The Symmetrical Array

At the heart of the Atmel FPSLIC architecture is a symmetrical array of identical cells. The array

is continuous from one edge to the other, except for bus repeaters spaced every four cells, see

Figure 2-1. At the intersection of each repeater row and column is a 32 x 4 RAM block accessi-

ble by adjacent buses. The RAM can be configured as either a single-ported or dual-ported

RAM, with either synchronous or asynchronous operation.

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1138H–FPSLI–6/05

2.6

The Busing Network

Figure 2-1. Busing Network

= RAM Block

= Repeater Row

= Repeater

= I/O Pad

= AT40K Cell

Interface to AVR

Figure 2-2 depicts one of five identical FPGA busing planes. Each plane has three bus

resources: a local-bus resource (the middle bus) and two express-bus resources. Bus resources

are connected via repeaters. Each repeater has connections to two adjacent local-bus segments

and two express-bus segments. Each local-bus segment spans four cells and connects to con-

secutive repeaters. Each express-bus segment spans eight cells and bypasses a repeater.

Repeaters regenerate signals and can connect any bus to any other bus (all pathways are legal)

on the same plane. Although not shown, a local bus can bypass a repeater via a programmable

pass gate, allowing long on-chip tri-state buses to be created. Local/local turns are implemented

through pass gates in the cell-bus interface. Express/express turns are implemented through

separate pass gates distributed throughout the array.

6

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 2-2. Busing Plane (One of Five)

= AT40K Core Cell

= Local/local or Express/express Turn Point

= Row Repeater

= Column

7

1138H–FPSLI–6/05

2.7

Cell Connections

In Figure 2-3 section (a) depicts direct connections between an FPGA cell and its eight nearest

neighbors. Section (b) of Figure 2-3 shows the connections between a cell five horizontal local

buses (one per busing plane) and five vertical local buses (one per busing plane).

Figure 2-3. Cell Connections

CELL

WXYZL

Y

X

W

X

Y

Z

Y

CELL

L

X

Y

CELL

(a) Cell-to-Cell Connections

(b) Cell-to-Bus Connections

2.8

The Cell

Figure 2-4 depicts the AT40K FPGA embedded core logic cell. Configuration bits for separate

muxes and pass gates are independent. All permutations of programmable muxes and pass

gates are legal. Vn is connected to the vertical local bus in plane n. Hn is connected to the hori-

zontal local bus in plane n. A local/local turn in plane n is achieved by turning on the two pass

gates connected to Vn and Hn. Up to five simultaneous local/local turns are possible.

The logic cell can be configured in several “modes”. The logic cell flexibility makes the FPGA

architecture well suited to all digital design application areas, see Figure 2-5. The IDS layout tool

automatically optimizes designs to utilize the cell flexibility.

8

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 2-4. The Cell

"1"

N

E

S

Y

W

"1" NW NE SE SW

"1"

X

W

Z

X

W

Y

FB

8 X 1 LUT

OUT

8 X 1 LUT

OUT

"1"

"0" "1"

V1

H1

V2

H2

V3

H3

V4

H4

V5

H5

1

0

Z

L

"1" OE OE

H

V

D

Q

CLOCK

RESET/SET

Y

X

NW NE SE SW

N

E

S

W

X

Y

= Diagonal Direct Connect or Bus

= Orthogonal Direct Connect or Bus

W = Bus Connection

= Bus Connection

FB = Internal Feedback

Z

9

1138H–FPSLI–6/05

Figure 2-5. Some Single Cell Modes

A

B

Q (Registered)

and/or

Q

Synthesis Mode

C

DQ

D

SUM

or

A

DQ

SUM (Registered)

and/or

Arithmetic Mode

B

C

CARRY

PRODUCT (Registered)

or

PRODUCT

DQ

A

B

C

D

DSP/Multiplier Mode

and/or

CARRY

DQ

Q

CARRY IN

Counter Mode

and/or

CARRY

A

B

C

Q

Tri-State/Mux Mode

EN

2.9

RAM

There are two types of RAM in the FPSLIC device: the FreeRAM distributed through the FPGA

Core and the SRAM shared by the AVR and FPGA. The SRAM is described in “FPGA/AVR

Interface and System Control” on page 21. The 32 x 4 dual-ported FPGA FreeRAM blocks are

dispersed throughout the array and are connected in each sector as shown in Figure 2-6. A four-

bit Input Data bus connects to four horizontal local buses (Plane 1) distributed over four sector

rows. A four-bit Output Data bus connects to four horizontal local buses (Plane 2) distributed

over four sector rows. A five-bit Input-address bus connects to five vertical express buses in the

same sector column (column 3). A five-bit Output-address bus connects to five vertical express

buses in the same column. WAddr (Write Address) and RAddr (Read Address) alternate posi-

10

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

tions in horizontally aligned RAM blocks. For the left-most RAM blocks, RAddr is on the left and

WAddr is on the right. For the right-most RAM blocks, WAddr is on the left and RAddr is tied off.

For single-ported RAM, WAddr is the READ/WRITE address port and Din is the (bi-directional)

data port. The right-most RAM blocks can be used only for single-ported memories. WE and OE

connect to the vertical express buses in the same column on Plane V₁and V₂, respectively.

WAddr, RAddr, WE and OE connect to express buses that are full length at array edge.

Reading and writing the 32 x 4 dual-port RAM are independent of each other. Reading the

32 x 4 dual-port RAM is completely asynchronous. Latches are transparent; when Load is logic

1, data flows through; when Load is logic 0, data is latched. Each bit in the 32 x 4 dual-port RAM

is also a transparent latch. The front-end latch and the memory latch together and form an edge-

triggered flip-flop. When a bit nibble is (Write) addressed and LOAD is logic 1 and WE is logic 0,

DATA flows through the bit. When a nibble is not (Write) addressed or LOAD is logic 0 or WE is

logic 1, DATA is latched in the nibble. The two CLOCK muxes are controlled together; they both

select CLOCK or they both select “1”. CLOCK is obtained from the clock for the sector-column

immediately to the left and immediately above the RAM block. Writing any value to the RAM

Clear Byte during configuration clears the RAM, see Figure 2-3 and

Figure 2-4.

Figure 2-6. FPGA RAM Connections (One RAM Block)

Sector Clock Mux

CLK

CLK Din

WAddr

Dout

RAddr

32X4 RAM

WE

OE

11

1138H–FPSLI–6/05

Figure 2-7. FreeRAM Logic⁽¹⁾

CLOCK

"1"

Load

5

Read

READ ADDR

5

Load

Latch

WRITE ADDR

32 x 4

Dual-port

RAM

Write

Data

"1"

OE

Load

Latch

WE

4

Load

Latch

DATA IN

Data

DATA

Clear

RAM-Clear

Note:

1. For dual port, the switches on READ ADDR and DATA OUT would be on. The other two would be off. The reverse is true for

single port.

12

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

2.10 Clocking and Set/Reset

Six of the eight dedicated Global Clock buses (1, 2, 3, 4, 7 and 8) are connected to a dual-use

Global Clock pin. In addition, two Global Clock buses (5 and 6) are driven from clock signals

generated within the AVR microcontroller core, see Figure 2-9.

An FPGA core internal signal can be placed on any Global Clock bus by routing that signal to a

Global Clock access point in the corners of the embedded core. Each column of the array has a

Column Clock selected from one of the eight Global Clock buses. The left edge Column Clock

mux has two additional inputs from dual-use pins FCK1, see Figure 2-6, and FCK2 to provide

fast clocking to left-side I/O. Each sector column of four cells can be clocked from a (Plane 4)

express bus or from the Column Clock. Clocking to the 4 cells of a sector can be disabled. The

Plane 4 express bus used for clocking is half length at the array edge. The clock provided to

each sector column of four cells can be either inverted or not inverted. The register in each cell is

triggered on a rising clock edge. On power-up, constant “0” is provided to each register’s clock

pins. A dedicated Global Set/Reset bus, see Figure 2-7, can be driven by any USER I/O pad,

except those used for clocking, Global or Fast. An internal signal can be placed on the Global

Set/Reset bus by routing that signal to the pad programmed as the Global Set/Reset input. Glo-

bal Set/Reset is distributed to each column of the array. Each sector column of four cells can be

Set/Reset by a (Plane 5) express bus or by the Global Set/Reset. The Plane 5 express bus used

for Set/Reset is half length at array edge. The Set/Reset provided to each sector column of four

cells can be either inverted or not inverted. The function of the Set/Reset input of a register

(either Set or Reset) is determined by a configuration bit for each cell. The Set/Reset input of a

register is Active Low (logic 0). Setting or resetting of a register is asynchronous. On power-up, a

logic 1 (High) is provided by each register, i.e., all registers are set at power-up.

Figure 2-9. FPGA Clocks from AVR

TO FPGA

AVR SYSTEM

CLOCK

CORE GCK5

(AVR CLK)

AVR SYSTEM CLOCK (AVR CLK)

TIMER OSC TOSC1 (AS2 SET IN ASSR)

TO FPGA

GCK6

CORE GCK6

WATCHDOG CLOCK

"1"

14

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

The FPGA clocks from the AVR are effected differently in the various sleep modes of the AVR,

see Table 2-1.

The source clock into the FPGA GCK5 and GCK6 will determine what happens during the vari-

ous power-down modes of the AVR.

If the XTAL clock input is used as an FPGA clock (GCK5 or GCK6) in Idle mode, it will still be

running. In Power-down/save mode the XTAL clock input will be off.

If the TOSC clock input is used as an FPGA clock (GCK6) in Idle mode, it will still be running in

Power-save mode but will be off in Power-down mode.

If the Watchdog Timer is used as an FPGA clock (GCK6) and was enabled in the AVR, it will be

running in all sleep modes.

Table 2-1.

Mode

Clock Activity in Various Modes

Clock Source

XTAL

GCK5

GCK6

Active

Inactive

Active

Inactive

Active

Idle

TOSC

WDT

Not Available

Inactive

XTAL

Power-save

Power-down

TOSC

WDT

Not Available

Inactive

XTAL

TOSC

WDT

Not Available

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1138H–FPSLI–6/05

Figure 2-10. Clocking (for One Column of Cells)

FCK⁽¹⁾

}

GCK1 − GCK8

"1"

Global Clock Line (Buried)

Express Bus

(Plane 4; Half Length at Edge)

"1"

Repeater

Note:

1. Two on left edge column of the embedded FPGA array only.

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AT94KAL Series FPSLIC

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AT94KAL Series FPSLIC

Figure 2-11. Set/Reset (for One Column of Cells)

Each Cell has a Programmable Set or Reset

Repeater

"1"

Global Set/Reset Line (Buried)

"1"

Express Bus

(Plane 5; Half Length at Edge)

"1"

Any User I/O can Drive Global Set/Reset Line

Some of the bus resources on the embedded FPGA core are used as dual-function resources.

Table 2-2 shows which buses are used in a dual-function mode and which bus plane is used.

The FPGA software tools are designed to automatically accommodate dual-function buses in an

efficient manner.

17

1138H–FPSLI–6/05

Table 2-2.

Function

Dual-function Buses

Type Plane(s)

Direction

Comments

Horizontal

and

Cell Output Enable Local

5

Vertical

FreeRAM Output

Enable

Bus full length at array edge bus in first

column to left of RAM block

Express

2

1

Vertical

FreeRAM Write

Enable

Bus full length at array edge bus in first

column to left of RAM block

Buses full length at array edge

buses in second column to left of

RAM block

FreeRAM Address Express

1 - 5

Vertical

FreeRAM

Local

1

2

Horizontal

Data In

FreeRAM

Local

Data Out

Clocking

Express

4

5

Vertical

Bus full length at array edge

Set/Reset

Figure 2-12. Primary I/O

CELL

"0"

"1"

PULL-UP

PAD

"0"

"1"

CELL

PULL-DOWN

CELL

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AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 2-13. Secondary I/O

"0"

"1"

CELL

PULL-UP

PAD

"0"

"1"

PULL-DOWN

CELL

Figure 2-14. Primary and Secondary I/Os

p

cell

p

cell

p

cell

p

cell

s

p

cell

s

p

cell

s

p

cell

s

p

cell

p

cell

p

s = secondary I/O

p = primary I/O

cell

19

1138H–FPSLI–6/05

Figure 2-15. Corner I/Os

PAD

VCC

GND

VCC

GND

TTL/CMOS

DRIVE

SCHMITT

DELAY

SCHMITT

DELAY

TRI-STATE

CLK

RST

CLK

RST

CLK

RST

CLK

"0"

"1"

PULL-UP

PAD

"0"

"1"

CELL

PULL-DOWN

CELL

20

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AT94KAL Series FPSLIC

3. FPGA/AVR Interface and System Control

The FPGA and AVR share a flexible interface which allows for many methods of system

integration.

• Both FPGA and AVR share access to the 15 ns dual-port SRAM.

• The AVR data bus interfaces directly into the FPGA busing resources, effectively treating the

FPGA as a large I/O device. Users have complete flexibility on the types of additional

peripherals which are placed and routed inside the FPGA user logic.

• Up to 16 decoded address lines are provided into the FPGA.

• Up to 16 interrupts are available from the FPGA to the AVR.

• The AVR can reprogram the FPGA during operation to create a dynamic reconfigurable

system (Cache Logic).

3.1

FPGA/AVR Interface – Memory-mapped Peripherals

The FPGA core can be directly accessed by the AVR core, see Figure 3-1. Four memory loca-

tions in the AVR memory map are decoded into 16 select lines (8 for AT94K05) and are

presented to the FPGA along with the AVR 8-bit data bus. The FPGA can be used to create

additional custom peripherals for the AVR microcontroller through this interface. In addition there

are 16 interrupt lines (8 for AT94K05) from the FPGA back into the AVR interrupt controller. Pro-

grammable peripherals or regular logic can use these interrupt lines. Full support for

programmable peripherals is available within the System Designer tool suite.

Figure 3-1. FPGA/AVR Interface: Interrupts and Addressing

Up to 16 Memory-mapped

Decoded Address

Lines from 4 I/O Memory

Space Addresses

ADDRESS

I/O Memory Address Bus

FPGAIORE

DECODER

4:16

DECODE

8-bit

Data Out

EMBEDDED

FPGA CORE

EMBEDDED

AVR CORE

8-bit Bi-directional Data Bus

FPGAIOWE

8-bit

Data In

Up to 16 Interrupt Lines from FPGA to AVR – Various Priority Levels

The FPGA I/O selection is controlled by the AVR. This is described in detail beginning on

page 55. The FPGA I/O interrupts are described beginning on page 59.

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3.2

Program and Data SRAM

Up to 36 Kbytes of 15 ns dual-port SRAM reside between the FPGA and the AVR. This SRAM is

used by the AVR for program instruction and general-purpose data storage. The AVR is con-

nected to one side of this SRAM; the FPGA is connected to the other side. The port connected

to the FPGA is used to store data without using up bandwidth on the AVR system data bus.

The FPGA core communicates directly with the data SRAM⁽¹⁾block, viewing all SRAM memory

space as 8-bit memory.

Note:

1. The unused bits for the FPGA-SRAM address must tie to ‘0’ because there is no pull-down

circuitry.

For the AT94K10 and AT94K40, the internal program and data SRAM is divided into three

blocks: 10 Kbytes x 16 dedicated program SRAM, 4 Kbytes x 8 dedicated data SRAM and 6

Kbytes x 16 or 12 Kbytes x 8 configurable SRAM, which may be swapped between program and

data memory spaces in 2 Kbytes x 16 or 4 Kbytes x 8 partitions.

For the AT94K05, the internal program and data SRAM is divided into three blocks: 4 Kbytes 16

dedicated program SRAM, 4 Kbytes x 8 dedicated data SRAM and 6 Kbytes x 16 or 12

Kbytes x 8 configurable SRAM, which may be swapped between program and data memory

spaces in 2 Kbytes x 16 or 4 Kbytes x 8 partitions.

The addressing scheme for the configurable SRAM partitions prevents program instructions

from overwriting data words and vice versa. Once configured (SCR41:40 – See “System Control

Register – FPGA/AVR” on page 30.), the program memory space remains isolated from the data

memory space. SCR41:40 controls internal muxes. Write enable signals allow the memory to be

safely segmented. Figure 3-2 shows the FPSLIC configurable allocation SRAM memory.

22

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 3-2. FPSLIC Configurable Allocation SRAM Memory⁽¹⁾⁽²⁾

Program SRAM Memory

SOFT “BOOT BLOCK”⁽¹⁾

$0000

$07FF

Memory Partition

is User Defined

during Development

FIXED

10K x 16

4 Kbytes x 16 (94K05)

Data SRAM Memory

$27FF

$2800

$3FFF

OPTIONAL

4 Kbytes x 8

2 Kbytes x 16

$2FFF

$3000

$2FFF

OPTIONAL

4 Kbytes x 8

2 Kbytes x 16

$37FF

$3800

$2000

$1FFF

OPTIONAL

4 Kbytes x 8

OPTIONAL

2 Kbytes x 16

$1000

$0FFF

$3FFF

FIXED

4 Kbytes x 8

$005F

AVR

DATA

SRAM

FPGA

ACCESS

ONLY

MEMORY

MAPPED

I/O

$001F

$0000

AVR REG.

SPACE⁽²⁾

Notes: 1. The Soft “BOOT BLOCK” is an area of memory that is first loaded when the part is powered up

and configured. The remainder of the memory can be reprogrammed while the device is in

operation for switching functions in and out of memory. The Soft “BOOT BLOCK” can only be

programmed by a full device configuration on power-up.

2. The lower portion of the Data memory is not shared between the AVR and FPGA. The AVR

uses addresses $0000 - $001F for the AVR CPU general working registers. $001F - $005F are

the addresses used for Memory Mapped I/O and store the information in dedicated registers.

Therefore, on the FPGA side $0000 - $005F are available for data that is only needed by the

FPGA.

23

1138H–FPSLI–6/05

3.3

Data SRAM Access by FPGA – FPGAFrame Mode

The FPGA user logic has access to the data SRAM directly through the FPGA side of the dual-

port memory, see Figure 3-3. A single bit in the configuration control register (SCR63 – see

“System Control Register – FPGA/AVR” on page 30) enables this interface. The interface is dis-

abled during configuration downloads. Express buses on the East edge of the array are used to

interface the memory. Full read and write access is available. To allow easy implementation, the

interface itself is dedicated in routing resources, and is controlled in the System Designer soft-

ware suite using the AVR FPGA interface dialog.

Figure 3-3. Internal SRAM Access – Normal Use

16 Address Lines:

FPGA Edge Express Buses

16-bit Data Address Bus

WE AVR

RE AVR

CLK AVR

WE FPGA

EMBEDDED

FPGA CORE

EMBEDDED

AVR CORE

DATA SRAM

CLK FPGA

SCR38

4 Kbytes x 8

UP TO

16 Kbytes x 8

8-bit Data Read

8-bit Data Read/Write

8-bit Data Write

B Side A Side

Once the SCR63 bit is set there is no additional read enable from the FPGA side. This means

that the read is always enabled. You can also perform a read or write from the AVR at the same

time as an FPGA read or write. If there is a possibility of a write address being accessed by both

devices at the same time, the designer should add arbitration to the FPGA Logic to control who

has priority. In most cases the AVR would be used to restrict access by the FPGA using the

FMXOR bit, see “Software Control Register – SFTCR” on page 52. You can read from the same

location from both sides simultaneously.

SCR bit 38 controls the polarity of the clock to the SRAM from the AT40K FPGA.

3.4

SRAM Access by FPGA/AVR

This option is used to allow for code (Program Memory) changes.

3.4.1

Accessing and Modifying the Program Memory from the AVR

The FPSLIC SRAM is up to 36 x 8 Kbytes of dual port, see Figure 3-2):

• The A side (port) is accessed by the AVR.

• The B side (port) is accessed by the FPGA/Configuration Logic.

• The B side (port) can be accessed by the AVR with ST and LD instructions in DBG mode for

code self-modify.

Structurally, the [(n • 2) Kbytes 8] memory is built from (n)2 Kbytes 8 blocks, numbered SRAM0

through SRAM(n).

24

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

3.4.2

A Side

The A side is partitioned into Program memory and Data memory:

• Program memory is 16-bit words.

• Program memory address $0000 always starts in the highest two SRAMs (n - 1, n) [SRAMn -

1 (low byte) and SRAMn (high byte)] (SRAM labels are for layout, the addressing scheme is

transparent to the AVR PC).

• System configuration determines the higher addresses for program memory:

– SCR bits 41 = 0 : 40 = 0, program memory extended from $2800 - $3FFF

– SCR bits 41 = 0 : 40 = 1, program memory extended from $2800 - $37FF

– SCR bits 41 = 1 : 40 = 0, program memory extended from $2800 - $2FFF

– SCR bits 41 = 1 : 40 = 1, no extra program memory

• Extended program memory is always lost to extended data memory from SRAM2/3 down to

SRAM6/7, see Table 3-1.

Table 3-1.

Address Range

$3FFF - $3800

AVR Program Decode for SRAM 2:7 (16K16)

SRAM

Comments

02

03

CR41:40 = 00

$3FFF - $3800

$37FF - $3000

04

05

CR41:40 = 00,01

$2FFF - $2800

06

07

CR41:40 = 00,01,10

$27FF - $2000

$1FFF - $1800

$17FF - $1000

$0FFF - $0800

$07FF - $0000

08

09

10

11

12

13

14

15

16

AVR Program Read-only

n = 17

• Data memory is 8-bit words.

• Data memory address $0000 always starts in SRAM0 (SRAM labels are for layout, the

addressing scheme is transparent to AVR data read/write).

• System configuration determines the higher address for data memory:

– SCR bits 41 = 0 : 40 = 0, no extra data memory

– SCR bits 41 = 0 : 40 = 1, data memory extended from $1000 - $1FFF

– SCR bits 41 = 1 : 40 = 0, data memory extended from $1000 - $2FFF

– SCR bits 41 = 1 : 40 = 1, data memory extended from $1000 - $3FFF

• Extended data memory is always lost to extended program memory from SRAM7 up to

SRAM2 in 2 x SRAM blocks, see Table 3-2.

25

1138H–FPSLI–6/05

Table 3-2.

Address Range

$07FF – $0000

AVR Data Decode for SRAM 0:17 (16K8)

SRAM

Comments

00

01

AVR Data Read/Write

$0FFF – $0800

$17FF – $1000

$1FFF – $1800

02

03

CR41:40 = 11,10,01

CR41:40 = 11,10

CR41:40 = 11

$27FF – $2000

$2FFF – $2800

04

05

$37FF – $3000

$3FFF – $3800

06

07

3.4.3

B Side

The B side is not partitioned; the FPGA (and AVR debug mode) views the memory space as

36 x 8 Kbytes.

• The B side is accessed by the FPGA/Configuration Logic.

• The B side is accessed by the AVR with ST and LD instructions in DBG mode for code self-

modify.

To activate the debug mode and allow the AVR to access the program code space (with ST

– see Figure 3-4 – and LD – see Figure 3-5 – instructions), the DBG bit (bit 1) of the SFTCR

$3A ($5A) register has to be set. When this bit is set, SCR36 and SCR37 are ignored – you

can overwrite anything in the AVR program memory.

The FPGA memory access interface should be disabled while in debug mode. This is to

ensure that there is no contention between the FPGA address and data signals and the

AVR-generated address and data signals. To ensure the AVR has control over the “B side”

memory interface, the FMXOR bit (bit 3) of the SFTCR $3A ($5A) register should be used in

conjunction with the SCR63 system control register bit.

The FMXOR bit is XORed with the System Control Register’s Enable FPGA SRAM Interface

bit (SCR63). The behavior when this bit is set to 1 is dependent on how the SCR was initial-

ized. If the Enable FPGA SRAM Interface bit (SCR63) in the SCR is 0, the FMXOR bit

enables the FPGA SRAM Interface when set to 1. If the Enable FPGA SRAM Interface bit in

the SCR is 1, the FMXOR bit disables the FPGA SRAM Interface when set to 1. During AVR

reset, the FMXOR bit is cleared by the hardware.

Even though the FPGA (and AVR debug mode) views the memory space as

36 x 8 Kbytes, an awareness of the 2K x 8 partitions (or SRAM labels) is required if Frame

(and AVR debug mode) read/writes are to be meaningful to the AVR.

• AVR data to FPGA addressing is 1:1 mapping.

• AVR program to FPGA addressing requires 16-bit to 8-bit mapping and an understanding of

the partitions in Table 3-3.

26

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 3-3.

Summary Table for AVR and FPGA SRAM Addressing

FPGA and AVR DBG

Address Range

AVR Data

Address Range

SRAM

00

AVR PC Address Range

$0000 - $07FF

$0800 - $0FFF

$1000 - $17FF

$1800 - $1FFF

$2000 - $27FF

$2800 - $2FFF

$3000 - $37FF

$3800 - $3FFF

$4000 - $47FF

$4800 - $4FFF

$5000 - $57FF

$5800 - $5FFF

$6000 - $67FF

$6800 - $6FFF

$7000 - $77FF

$7800 - $7FFF

$8000 - $87FF

$8800 - $8FFF

$0000 - $07FF

$0800 - $0FFF

$1000 - $17FF

$1800 - $1FFF

$2000 - $27FF

$2800 - $2FFF

$3000 - $37FF

$3800 - $3FFF

01

02⁽¹⁾

03⁽¹⁾

04⁽¹⁾

05⁽¹⁾

06⁽¹⁾

07⁽¹⁾

08

$3800 - $3FFF (LS Byte)

$3800 - $3FFF (MS Byte)

$3000 - $37FF (LS Byte)

$3000 - $37FF (MS Byte)

$2800 - $2FFF (LS Byte)

$2800 - $2FFF (MS Byte)

$2000 - $27FF (LS Byte)

$2000 - $27FF (MS Byte)

$1800 - $1FFF (LS Byte)

$1800 - $1FFF (MS Byte)

$1000 - $17FF (LS Byte)

$1000 - $17FF (MS Byte)

$0800 - $0FFF (LS Byte)

$0800 - $0FFF (MS Byte)

$0000 - $07FF (LS Byte)

$0000 - $07FF (MS Byte)

09

10

11

12

13

14

15

16

17 = n

Note:

1. Whether these SRAMs are “Data” or “Program” depends on the SCR40 and SCR41 values.

Example: Frame (and AVR debug mode) write of instructions to associated AVR PC addresses,

see Table 3-4 and Table 3-5.

Table 3-4.

AVR PC Addresses

AVR PC

0ffe

Instruction

9b28

0fff

cffe

1000

1001

b300

9a39

Table 3-5.

Frame Addresses

Frame Address

Frame Data

77fe

77ff

28

fe

6000

6001

7ffe

00

39

9b

cf

7fff

6800

6801

b3

9a

27

1138H–FPSLI–6/05

Figure 3-4. AVR SRAM Data Memory Write Using “ST” Instruction

CLOCK

RAMWE

RAMADR

DBUS

VALID

DBUSOUT

(REGISTERED)

VALID

ST cycle 2 next instruction

ST cycle 1

Figure 3-5. AVR SRAM Data Memory Read Using “LD” Instruction

CLOCK

RAMRE

RAMADR

DBUS

VALID

LD cycle 2 next instruction

LD cycle 1

28

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

3.5

AVR Cache Mode

The AVR has the ability to cache download the FPGA memory. The AVR has direct access to

the data buses of the FPGA’s configuration SRAM and is able to download bitstreams. AVR

Cache access of configuration SRAM is not available during normal configuration downloads.

The Cache Logic port in the AVR is located in the I/O memory map. Three registers, FPGAX,

FPGAY FPGAZ, control the address written to inside the FPGA; and FPGAD in the AVR mem-

ory map controls the Data. Registers FPGAX, FPGAY and FPGAZ are write only, see

Figure 3-6.

Figure 3-6. Internal FPGA Configuration Access

Configuration Logic

EMBEDDED

AVR CORE

FPGAX [7:0]

Memory-mapped

EMBEDDED

FPGA CORE

Location

FPGAY [7:0]

FPGAZ [7:0]

FPGAD [7:0]

Memory-mapped

Location

8-bit Configuration

Memory Write Data

24-bit Address Write

Memory-mapped

Location

Memory-mapped

Location

(Operation is not

interrupted during

Cache Logic

CACHEIOWE

loading)

Configuration Clock – Each tick is generated when the Memory-

mapped I/O location FPGAD is written to inside the AVR.

The AVR Cache Logic access mode is write only. Transfers may be aborted at any time due to

AVR program wishes or external interrupts.

The FPGA CHECK function is not supported by the AVR Cache mode.

A typical application for this mode is for the AVR to accept serial data through a UART for exam-

ple, and port it as configuration data to the FPGA, thereby affecting a download, or allowing

reconfigurable systems where the FPGA is updated algorithmically by the AVR. For more infor-

mation, refer to the “AT94K Series Configuration” application note available on the Atmel web

site, at: http://www.atmel.com/atmel/acrobat/doc2313.pdf.

3.6

Resets

The user must have the flexibility to issue resets and reconfiguration commands to separate por-

tions of the device. There are two Reset pins on the FPSLIC device. The first, RESET, results in

a clearing of all FPGA configuration SRAM and the System Control Register, and initiates a

download if in mode 0. The AVR will stop and be reset.

A second reset pin, AVRReset, is implemented to reset the AVR portion of the FPSLIC func-

tional blocks. This is described in the “Reset Sources” on page 63.

29

1138H–FPSLI–6/05

3.7

System Control

3.7.1

Configuration Modes

The AT94K family has four configuration modes controlled by mode pins M0 and M2, see Table

3-6.

Table 3-6.

Configuration Modes

M2

0

M0

0

Name

Mode 0 - Master Serial

Mode 1 - Slave Serial Cascade

Mode 2 - Reserved

Mode 3 - Reserved

0

1

0

1

Modes 2 and 3 are reserved and are used for factory test.

Modes 0 and 1 are pin-compatible with the appropriate AT40K counterpart. AVR I/O will be

taken over by the configuration logic for the CHECK pin during both modes.

Refer to the “AT94K Series Configuration” application note for details on downloading

bitstreams.

3.7.2

System Control Register – FPGA/AVR

The configuration control register in the FPSLIC consists of 8 bytes of data, which are loaded

with the FPGA/Prog. Code at power-up from external nonvolatile memory. FPSLIC System Con-

trol Register values, see Table 3-7, can be set in the System Designer software. Recommended

defaults are included in the software.

Table 3-7.

Bit

FPSLIC System Control Register

Description

SCR0 - SCR1

Reserved

0 = Enable Cascading

1 = Disable Cascading

SCR2 controls the operation of the dual-function I/O CSOUT. When SCR2 is set,

the CSOUT pin is not used by the configuration during downloads, set this bit for

configurations where two or more devices are cascaded together. This applies for

configuration to another FPSLIC device or to an FPGA.

SCR2

SCR3

0 = Check Function Enabled

1 = Check Function Disabled

SCR3 controls the operation of the CHECK pin and enables the Check Function.

When SCR3 is set, the dual use AVR I/O/CHECK pin is not used by the

configuration during downloads, and can be used as AVR I/O.

0 = Memory Lockout Disabled

1 = Memory Lockout Enabled

SCR4 is the Security Flag and controls the writing and checking of configuration

memory during any subsequent configuration download. When SCR4 is set, any

subsequent configuration download initiated by the user, whether a normal

download or a CHECK function download, causes the INIT pin to immediately

activate. CON is released, and no further configuration activity takes place. The

download sequence during which SCR4 is set is NOT affected. The Control

Register write is also prohibited, so bit SCR4 may only be cleared by a power-on

reset or manual reset.

SCR4

30

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 3-7.

Bit

FPSLIC System Control Register (Continued)

Description

SCR5

Reserved

0 = OTS Disabled

1 = OTS Enabled

SCR6

Setting SCR6 makes the OTS (output tri-state) pin an input which controls the

global tri-state control for all user I/O. This junction allows the user at any time to

tristate all user I/O and isolate the chip.

SCR7 - SCR12

Reserved

0 = CCLK Normal Operation

1 = CCLK Continues After Configuration.

Setting bit SCR13 allows the CCLK pin to continue to run after configuration

download is completed. This bit is valid for Master mode, mode 0 only. The CCLK

is not available internally on the device. If it is required in the design, it must be

connected to another device I/O.

SCR13

SCR14 - SCR15 Reserved

0 = GCK 0:7 Always Enabled

1 = GCK 0:7 Disabled During Internal and External Configuration Download.

Setting SCR16:SCR23 allows the user to disable the input buffers driving the

SCR16 - SCR23 global clocks. The clock buffers are enabled and disabled synchronously with the

rising edge of the respective GCK signal, and stop in a High “1” state. Setting one

of these bits disables the appropriate GCK input buffer only and has no effect on

the connection from the input buffer to the FPGA array.

0 = FCK 0:1 Always Enabled

1 = FCK 0:1 Disabled During Internal and External Configuration Download.

Setting SCR24:SCR25 allows the user to disable the input buffers driving the fast

SCR24 - SCR25 clocks. The clock buffers are enabled and disabled synchronously with the rising

edge of the respective FCK signal, and stop in a High “1” state. Setting one of

these bits disables the appropriate FCK input buffer only and has no effect on the

connection from the input buffer to the FPGA array.

0 = Disable On-chip Debugger

1 = Enable On-chip Debugger.

SCR26

SCR27

JTAG Enable, SCR27, must also be set (one) and the configuration memory

lockout, SCR4, must be clear (zero) for the user to have access to internal scan

chains.

0 = Disable TAP at user FPGA I/O Ports

1 = Enable TAP at user FPGA I/O Ports.

Device ID scan chain and AVR I/O boundary scan chain are available. The user

must set (one) the On-chip Debug Enable, SCR26, and must keep the

configuration memory lockout, SCR4, clear (zero) for the user to have access to

internal scan chains.

SCR28 - SCR29 Reserved

0 = Global Set/Reset Normal

1 = Global Set/Reset Active (Low) During Internal and External Configuration

Download.

SCR30 allows the Global set/reset to hold the core DFFs in reset during any

configuration download. The Global set/reset net is released at the end of

configuration download on the rising edge of CON, if set.

SCR30

31

1138H–FPSLI–6/05

Table 3-7.

Bit

FPSLIC System Control Register (Continued)

Description

0 = Disable I/O Tri-state

1 = I/O Tri-state During (Internal and External) Configuration Download.

SCR31 forces all user defined I/O pins to go tri-state during configuration

download. Tri-state is released at the end of configuration download on the rising

edge of CON, if set.

SCR31

SCR32 - SCR34 Reserved

0 = AVR Reset Pin Disabled

SCR35

1 = AVR Reset Pin Enabled (active Low Reset)

SCR35 allows the AVR Reset pin to reset the AVR only.

0 = Protect AVR Program SRAM

SCR36

SCR37

1 = Allow Writes to AVR Program SRAM (Excluding Boot Block)

SCR36 protects AVR program code from writes by the FPGA.

0 = AVR Program SRAM Boot Block Protect

1 = AVR Program SRAM Boot Block Allows Overwrite

0 = (default) Frame Clock Inverted to AVR Data/Program SRAM

1 = Non-inverting Clock Into AVR Data/Program SRAM

SCR38

SCR39

Reserved

SCR41 = 0, SCR40 = 0 16 Kbytes x 16 Program/4 Kbytes x 8 Data

SCR41 = 0, SCR40 = 1 14 Kbytes x 16 Program/8 Kbytes x 8 Data

SCR41 = 1, SCR40 = 0 12 Kbytes x 16 Program/12 Kbytes x 8 Data

SCR41 = 1, SCR40 = 1 10 Kbytes x 16 Program/16 Kbytes x 8 Data

SCR40 : SCR41 AVR program/data SRAM partitioning (set by using the AT94K

Device Options in System Designer).

SCR40 - SCR41

SCR 42 -

SCR47

Reserved

0 = EXT-INT0 Driven By Port E<4>

SCR48

SCR49

SCR50

SCR51

SCR52

1 = EXT-INT0 Driven By INTP0 pad

SCR48 : SCR53 Defaults dependent on package selected.

0 = EXT-INT1 Driven By Port E<5>

1 = EXT-INT1 Driven By INTP1 pad

SCR48 : SCR53 Defaults dependent on package selected.

0 = EXT-INT2 Driven By Port E<6>

1 = EXT-INT2 Driven By INTP2 pad

SCR48 : SCR53 Defaults dependent on package selected.

0 = EXT-INT3 Driven By Port E<7>

1 = EXT-INT3 Driven By INTP3 pad

SCR48 : SCR53 Defaults dependent on package selected.

0 = UART0 Pins Assigned to Port E<1:0>

1 = UART0 Pins Assigned to UART0 pads

SCR48 : SCR53 Defaults dependent on package selected.

0 = UART1 Pins Assigned to Port E<3:2>

1 = UART1 Pins Assigned to UART1 pads

SCR48 : SCR53 Defaults dependent on package selected.

SCR53

On packages less than 144-pins, there is reduced access to AVR ports. Port D is

not available externally in the smallest package and Port E becomes dual-purpose

I/O to maintain access to the UARTs and external interrupt pins. The Pin List (East

Side) on page 189 shows exactly which pins are available in each package.

32

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 3-7.

Bit

FPSLIC System Control Register (Continued)

Description

0 = AVR Port D I/O With 6 mA Drive

1 = AVR Port D I/O With 20 mA Drive

SCR54

SCR55

SCR56

SCR57

0 = AVR Port E I/O With 6 mA Drive

1 = AVR Port E I/O With 20 mA Drive

0 = Disable XTAL Pin (R_feedback

)

1 = Enable XTAL Pin (R_feedback

)

0 = Disable TOSC2 Pin (R_feedback

1 = Enable TOSC2 Pin (R_feedback

)

SCR58 - SCR59 Reserved

SCR61 = 0, SCR60 = 0 “1”

SCR61 = 0, SCR60 = 1 AVR System Clock

SCR61 = 1, SCR60 = 0 Timer Oscillator Clock (TOSC1)⁽¹⁾

SCR61 = 1, SCR60 = 1 Watchdog Clock

SCR60 - SCR61

Global Clock 6 mux select (set by using the AT94K Device Options in System

Designer).

Note:

1. The AS2 bit must be set in the ASSR register.

0 = Disable CacheLogic Writes to FPGA by AVR

1 = Enable CacheLogic Writes to FPGA by AVR

SCR62

SCR63

0 = Disable Access (Read and Write) to SRAM by FPGA

1 = Enable Access (Read and Write) to SRAM by FPGA

33

1138H–FPSLI–6/05

4. AVR Core and Peripherals

• AVR Core

• Watchdog Timer/On-chip Oscillator

• Oscillator-to-Internal Clock Circuit

• Oscillator-to-Timer/Counter for Real-time Clock

• 16-bit Timer/Counter and Two 8-bit Timer/Counters

• Interrupt Unit

• Multiplier

• UART (0)

• UART (1)

• I/O Port D (full 8 bits available on 144-pin or higher devices)

• I/O Port E

The embedded AVR core is a low-power CMOS 8-bit microcontroller based on the AVR RISC

architecture. The embedded AVR core achieves throughputs approaching 1 MIPS per MHz by

executing powerful instructions in a single-clock-cycle, and allows the system architect to opti-

mize power consumption versus processing speed.

The AVR core is based on an enhanced RISC architecture that combines a rich instruction set

with 32 x 8 general-purpose working registers. All the 32 x 8 registers are directly connected to

the Arithmetic Logic Unit (ALU), allowing two independent register bytes to be accessed in one

single instruction executed in one clock cycle. The resulting architecture is more code efficient

while achieving throughputs up to ten times faster than conventional CISC microcontrollers.

The embedded AVR core provides the following features: 16 general-purpose I/O lines, 32 x 8

general-purpose working registers, Real-time Counter (RTC), 3 flexible timer/counters with com-

pare modes and PWM, 2 UARTs, programmable Watchdog Timer with internal oscillator, 2-wire

serial port, and three software-selectable Power-saving modes. The Idle mode stops the CPU

while allowing the SRAM, timer/counters, two-wire serial port, and interrupt system to continue

functioning. The Power-down mode saves the register contents but freezes the oscillator, dis-

abling all other chip functions until the next interrupt or hardware reset. In Power-save mode, the

timer oscillator continues to run, allowing the user to maintain a timer base while the rest of the

device is sleeping.

The embedded AVR core is supported with a full suite of program and system development

tools, including C compilers, macro assemblers, program debugger/simulators and evaluation

kits.

34

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.1

Instruction Set Nomenclature (Summary)

The complete “AVR Instruction Set” document is available on the Atmel web site, at

http://www.atmel.com/atmel/acrobat/doc0856.pdf.

4.1.1

Status Register (SREG)

SREG:

Status register

C:

Z:

N:

V:

S:

H:

T:

I:

Carry flag in status register

Zero flag in status register

Negative flag in status register

Two’s complement overflow indicator

N

V, For signed tests

Half-carry flag in the status register

Transfer bit used by BLD and BST instructions

Global interrupt enable/disable flag

4.1.2

Registers and Operands

Rd:

Destination (and source) register in the register file

Source register in the register file

Rr:

R:

Result after instruction is executed

Constant data

K:

k:

Constant address

b:

Bit in the register file or I/O register (0 ≤ b ≤ 7)

Bit in the status register (0 ≤ s ≤ 2)

Indirect address register (X = R27:R26, Y = R29:R28 and Z = R31:R30)

I/O location address

s:

X,Y,Z:

A:

q:

Displacement for direct addressing (0 ≤ q ≤ 63)

4.1.3

I/O Registers

4.1.3.1

Stack

STACK:

Stack for return address and pushed registers

Stack Pointer to STACK

SP:

4.1.3.2

Flags

:

Flag affected by instruction

Flag cleared by instruction

Flag set by instruction

0:

1:

-:

Flag not affected by instruction

The instructions EIJMP, EICALL, ELPM, GPM, ESPM (from the megaAVR Instruction Set) are

not supported in the FPSLIC device.

35

1138H–FPSLI–6/05

Table 4-1.

Conditional Branch Summary

Test

Boolean

Z•(N V) = 0

(N V) = 0

Z = 1

Mnemonic

BRLT

Complementary

Rd ≤ Rr

Boolean

Z+(N V) = 1

(N V) = 1

Z = 0

Mnemonic

BRGE

Comment

Signed

Rd > Rr

Rd ≥ Rr

Rd = Rr

Rd ≤ Rr

Rd < Rr

Rd > Rr

Rd ≥ Rr

Rd = Rr

Rd ≤ Rr

Rd < Rr

Carry

BRGE

Rd < Rr

BRLT

Signed

BREQ

Rd ≠ Rr

BRNE

Signed

Z+(N V) = 1

(N V) = 1

C + Z = 0

C = 0

BRGE

Rd > Rr

Z•(N V) = 0

(N V) = 0

C + Z = 1

C = 1

BRLT

Signed

BRLT

Rd ≥ Rr

BRGE

Signed

BRLO

Rd ≤ Rr

BRSH

Unsigned

Simple

BRSH/BRCC

BREQ

Rd < Rr

BRLO/BRCS

BRNE

Z = 1

Rd ≠ Rr

Z = 0

C + Z = 1

C = 1

BRSH

Rd > Rr

C + Z = 0

C = 0

BRLO

BRLO/BRCS

BRCS

Rd ≥ Rr

BRSH/BRCC

BRCC

C = 1

No Carry

Positive

C = 0

Negative

Overflow

Zero

N = 1

BRMI

N = 0

BRPL

Simple

V = 1

BRVS

No Overflow

Not Zero

V = 0

BRVC

Simple

Z = 1

BREQ

Z = 0

BRNE

Simple

4.2

Complete Instruction Set Summary

Table 4-2.

Mnemonics

Instruction Set Summary

Operands Description

Operation

Flags

#Clock

Arithmetic and Logic Instructions

Rd ← Rd + Rr

ADD

ADC

ADIW

SUB

SUBI

SBC

SBCI

SBIW

AND

ANDI

OR

Rd, Rr

Rd, K

Rd, Rr

Rd, K

Rd, Rr

Rd, K

Rd, Rr

Rd, K

Rd, Rr

Rd, K

Rd, Rr

Rd

Add without Carry

Add with Carry

Z,C,N,V,S,H

1

2

1

2

1

Rd ← Rd + Rr + C

Z,C,N,V,S,H

Z,C,N,V,S

Z,C,N,V,S,H

Z,C,N,V,S

Z,N,V,S

Add Immediate to Word

Subtract without Carry

Subtract Immediate

Subtract with Carry

Rd+1:Rd ← Rd+1:Rd + K

Rd ← Rd - Rr

Rd ← Rd - K

Rd ← Rd - Rr - C

Rd ← Rd - K - C

Rd+1:Rd ← Rd+1:Rd - K

Rd ← Rd • Rr

Subtract Immediate with Carry

Subtract Immediate from Word

Logical AND

Logical AND with Immediate

Logical OR

Rd ← Rd • K

Z,N,V,S

Rd ← Rd v Rr

Z,N,V,S

ORI

Logical OR with Immediate

Exclusive OR

Rd ← Rd v K

Z,N,V,S

EOR

COM

NEG

SBR

CBR

Rd ← Rd Rr

Z,N,V,S

One’s Complement

Rd ← $FF - Rd

Rd ← $00 - Rd

Rd ← Rd v K

Z,C,N,V,S

Z,C,N,V,S,H

Z,N,V,S

Rd

Two’s Complement

Rd, K

Set Bit(s) in Register

Clear Bit(s) in Register

Rd ← Rd • ($FFh - K)

Z,N,V,S

36

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 4-2.

Mnemonics

INC

Instruction Set Summary (Continued)

Operands Description

Operation

Flags

Z,N,V,S

None

Z,C

#Clock

Rd

Increment

Rd ← Rd + 1

1

2

DEC

Rd

Decrement

Rd ← Rd - 1

TST

Rd

Test for Zero or Minus

Clear Register

Rd ← Rd • Rd

CLR

Rd

Rd ← Rd Rd

SER

Rd

Set Register

Rd ← $FF

MUL

Rd, Rr

Multiply Unsigned

Multiply Signed

R1:R0 ← Rd × Rr (UU)

R1:R0 ← Rd × Rr (SS)

R1:R0 ← Rd × Rr (SU)

R1:R0 ← (Rd × Rr)<<1 (UU)

R1:R0 ← (Rd × Rr)<<1 (SS)

MULS

MULSU

FMUL

FMULS

Z,C

Multiply Signed with Unsigned

Fractional Multiply Unsigned

Fractional Multiply Signed

Z,C

Fractional Multiply Signed with

Unsigned

FMULSU

Rd, Rr

R1:R0 ← (Rd × Rr)<<1 (SU)

Z,C

2

Branch Instructions

RJMP

IJMP

JMP

k

Relative Jump

PC ← PC + k + 1

None

2

Indirect Jump to (Z)

Jump

PC(15:0) ← Z

None

2

k

PC ← k

None

3

RCALL

ICALL

CALL

RET

Relative Call Subroutine

Indirect Call to (Z)

PC ← PC + k + 1

None

3

PC(15:0) ← Z

None

3

k

Call Subroutine

PC ← k

None

4

Subroutine Return

PC ← STACK

None

4

RETI

CPSE

CP

Interrupt Return

PC ← STACK

I

4

Rd, Rr

Rd, K

Rr, b

A, b

s, k

k

Compare, Skip if Equal

Compare

if (Rd = Rr) PC ← PC + 2 or 3

Rd - Rr

None

1 / 2 / 3

1

Z,C,N,V,S,H

None

CPC

Compare with Carry

Compare with Immediate

Skip if Bit in Register Cleared

Skip if Bit in Register Set

Skip if Bit in I/O Register Cleared

Skip if Bit in I/O Register Set

Branch if Status Flag Set

Branch if Status Flag Cleared

Branch if Equal

Rd - Rr - C

1

CPI

Rd - K

1

SBRC

SBRS

SBIC

SBIS

BRBS

BRBC

BREQ

BRNE

BRCS

BRCC

BRSH

if (Rr(b) = 0) PC ← PC + 2 or 3

if (Rr(b) = 1) PC ← PC + 2 or 3

if(I/O(A,b) = 0) PC ← PC + 2 or 3

If(I/O(A,b) = 1) PC ← PC + 2 or 3

if (SREG(s) = 1) then PC ←PC+k+1

if (SREG(s) = 0) then PC ←PC+k+1

if (Z = 1) then PC ← PC + k + 1

if (Z = 0) then PC ← PC + k + 1

if (C = 1) then PC ← PC + k + 1

if (C = 0) then PC ← PC + k + 1

1 / 2 / 3

1 / 2

None

k

Branch if Not Equal

Branch if Carry Set

Branch if Carry Cleared

Branch if Same or Higher

None

k

None

k

None

k

None

37

1138H–FPSLI–6/05

Table 4-2.

Mnemonics

BRLO

BRMI

Instruction Set Summary (Continued)

Operands Description

Operation

Flags

None

#Clock

1 / 2

k

Branch if Lower

if (C = 1) then PC ← PC + k + 1

if (N = 1) then PC ← PC + k + 1

if (N = 0) then PC ← PC + k + 1

if (N V= 0) then PC ← PC + k + 1

if (N V= 1) then PC ← PC + k + 1

if (H = 1) then PC ← PC + k + 1

if (H = 0) then PC ← PC + k + 1

if (T = 1) then PC ← PC + k + 1

if (T = 0) then PC ← PC + k + 1

if (V = 1) then PC ← PC + k + 1

if (V = 0) then PC ← PC + k + 1

if (I = 1) then PC ← PC + k + 1

if (I = 0) then PC ← PC + k + 1

Branch if Minus

BRPL

Branch if Plus

BRGE

BRLT

Branch if Greater or Equal, Signed

Branch if Less Than, Signed

Branch if Half-carry Flag Set

Branch if Half-carry Flag Cleared

Branch if T Flag Set

BRHS

BRHC

BRTS

BRTC

Branch if T Flag Cleared

Branch if Overflow Flag is Set

Branch if Overflow Flag is Cleared

Branch if Interrupt Enabled

Branch if Interrupt Disabled

BRVS

BRVC

BRIE

BRID

Data Transfer Instructions

MOV

MOVW

LDI

LDS

LD

Rd, Rr

Rd, K

Rd, k

Copy Register

Rd ← Rr

None

1

2

Copy Register Pair

Rd+1:Rd ← Rr+1:Rr

Rd ← K

Load Immediate

Load Direct from Data Space

Load Indirect

Rd ← (k)

Rd, X

Rd, X+

Rd, -X

Rd, Y

Rd, Y+

Rd, -Y

Rd, Y+q

Rd, Z

Rd ← (X)

LD

Load Indirect and Post-Increment

Load Indirect and Pre-Decrement

Load Indirect

Rd ← (X), X ← X + 1

X ← X - 1, Rd ← (X)

Rd ← (Y)

LD

Load Indirect and Post-Increment

Load Indirect and Pre-Decrement

Load Indirect with Displacement

Load Indirect

Rd ← (Y), Y ← Y + 1

Y ← Y - 1, Rd ← (Y)

Rd ← (Y + q)

LD

LDD

LD

Rd ← (Z)

LD

Rd, Z+

Rd, -Z

Rd, Z+q

k, Rr

Load Indirect and Post-Increment

Load Indirect and Pre-Decrement

Load Indirect with Displacement

Store Direct to Data Space

Store Indirect

Rd ← (Z), Z ← Z+1

Z ← Z - 1, Rd ← (Z)

Rd ← (Z + q)

LD

LDD

STS

ST

Rd ← (k)

X, Rr

(X) ← Rr

ST

X+, Rr

-X, Rr

Y, Rr

Store Indirect and Post-Increment

Store Indirect and Pre-Decrement

Store Indirect

(X) ← Rr, X ← X + 1

X ← X - 1, (X) ← Rr

(Y) ← Rr

ST

Y+, Rr

-Y, Rr

Store Indirect and Post-Increment

Store Indirect and Pre-Decrement

(Y) ← Rr, Y ← Y + 1

Y ← Y - 1, (Y) ← Rr

ST

38

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 4-2.

Mnemonics

STD

Instruction Set Summary (Continued)

Operands Description

Operation

Flags

None

#Clock

Y+q, Rr

Z, Rr

Store Indirect with Displacement

Store Indirect

(Y + q) ← Rr

(Z) ← Rr

2

3

ST

Z+, Rr

-Z, Rr

Store Indirect and Post-Increment

Store Indirect and Pre-Decrement

Store Indirect with Displacement

Load Program Memory

(Z) ← Rr, Z ← Z + 1

Z ← Z - 1, (Z) ← Rr

(Z + q) ← Rr

R0 ← (Z)

ST

STD

Z+q, Rr

LPM

Rd, Z

Load Program Memory

Rd ← (Z)

Load Program Memory and Post-

Increment

LPM

Rd, Z+

Rd ← (Z), Z ← Z + 1

None

3

IN

Rd, A

A, Rr

Rr

In From I/O Location

Out To I/O Location

Rd ← I/O(A)

I/O(A) ← Rr

STACK ← Rr

Rd ← STACK

None

1

2

OUT

PUSH

POP

Push Register on Stack

Pop Register from Stack

Rd

Bit and Bit-test Instructions

LSL

Rd

s

Logical Shift Left

Rd(n+1)←Rd(n),Rd(0)←0,C←Rd(7)

Z,C,N,V,H

1

2

1

LSR

ROL

ROR

ASR

SWAP

BSET

BCLR

SBI

Logical Shift Right

Rotate Left Through Carry

Rotate Right Through Carry

Arithmetic Shift Right

Swap Nibbles

Rd(n)←Rd(n+1),Rd(7)←0,C←Rd(0)

Z,C,N,V

Rd(0)←C,Rd(n+1)←Rd(n),C←Rd(7)

Z,C,N,V,H

Rd(7)←C,Rd(n)←Rd(n+1),C←Rd(0)

Z,C,N,V

Rd(n) ← Rd(n+1), n=0..6

Rd(3..0) ↔ Rd(7..4)

SREG(s) ← 1

SREG(s) ← 0

I/O(A, b) ← 1

I/O(A, b) ← 0

T ← Rr(b)

Rd(b) ← T

C ← 1

Z,C,N,V

None

Flag Set

SREG(s)

s

Flag Clear

SREG(s)

A, b

Rr, b

Rd, b

Set Bit in I/O Register

Clear Bit in I/O Register

Bit Store from Register to T

Bit load from T to Register

Set Carry

None

CBI

None

BST

BLD

SEC

CLC

SEN

CLN

SEZ

CLZ

SEI

T

None

C

N

Z

I

Clear Carry

C ← 0

Set Negative Flag

Clear Negative Flag

Set Zero Flag

N ← 1

N ← 0

Z ← 1

Clear Zero Flag

Z ← 0

Global Interrupt Enable

Global Interrupt Disable

Set Signed Test Flag

Clear Signed Test Flag

I ← 1

CLI

I ← 0

I

SES

CLS

S ← 1

S

S ← 0

39

1138H–FPSLI–6/05

Table 4-2.

Mnemonics

SEV

Instruction Set Summary (Continued)

Operands Description

Set Two’s Complement Overflow

Clear Two’s Complement Overflow

Set T in SREG

Operation

V ← 1

Flags

V

#Clock

1

CLV

V ← 0

V

1

SET

T ← 1

T

1

CLT

Clear T in SREG

T ← 0

T

1

SEH

Set Half-carry Flag in SREG

Clear Half-carry Flag in SREG

No Operation

H ← 1

H ← 0

H

1

CLH

H

1

NOP

None

1

SLEEP

WDR

Sleep

(See specific description for Sleep)

(See specific description for WDR)

For on-chip debug only

1

Watchdog Reset

1

BREAK

Break

N/A

4.3

Pin Descriptions

4.3.1

V_CC

Supply voltage

4.3.2

4.3.3

GND

Ground

PortD (PD7..PD0)

Port D is an 8-bit bi-directional I/O port with internal programmable pull-up resistors. The Port D

output buffers can be programmed to sink/source either 6 or 20 mA (SCR54 – see “System Con-

trol Register – FPGA/AVR” on page 30). As inputs, Port D pins that are externally pulled Low will

source current if the programmable pull-up resistors are activated.

The Port D pins are input with pull-up when a reset condition becomes active, even if the clock is

not running. On lower pin count packages Port D may not be available. Check the Pin List for

details.

4.3.4

PortE (PE7..PE0)

Port E is an 8-bit bi-directional I/O port with internal programmable pull-up resistors. The Port E

output buffers can be programmed to sink/source either 6 or 20 mA (SCR55 – see “System Con-

trol Register – FPGA/AVR” on page 30). As inputs, Port E pins that are externally pulled Low will

source current if the pull-up resistors are activated.

Port E also serves the functions of various special features. See Table 4-35 on page 160.

The Port E pins are input with pull-up when a reset condition becomes active, even if the clock is

not running

4.3.5

4.3.6

RX0

TX0

Input (receive) to UART(0) – See SCR52

Output (transmit) from UART(0) – See SCR52

40

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.3.7

RX1

Input (receive) to UART(1) – See SCR53

4.3.8

TX1

Output (transmit) from UART(1) – See SCR53

4.3.9

XTAL1

XTAL2

TOSC1

TOSC2

SCL

Input to the inverting oscillator amplifier and input to the internal clock operating circuit.

Output from the inverting oscillator amplifier

4.3.10

4.3.11

4.3.12

4.3.13

4.3.14

Input to the inverting timer/counter oscillator amplifier

Output from the inverting timer/counter oscillator amplifier

2-wire serial input/output clock

SDA

2-wire serial input/output data

4.4

Clock Options

4.4.1

Crystal Oscillator

XTAL1 and XTAL2 are input and output, respectively, of an inverting amplifier, which can be

configured for use as an on-chip oscillator, as shown in Figure 4-1. Either a quartz crystal or a

ceramic resonator may be used.

Figure 4-1. Oscillator Connections

MAX 1 HC BUFFER

HC

C2

C1

C2 = 27 pf

C1 = 33 pf

XTAL2

R_BIAS

XTAL1

GND

41

1138H–FPSLI–6/05

4.4.2

External Clock

To drive the device from an external clock source, XTAL2 should be left unconnected while

XTAL1 is driven as shown in Figure 4-2.

Figure 4-2. External Clock Drive Configuration

XTAL2

XTAL1

GND

NC

EXTERNAL

OSCILLATOR

SIGNAL

4.4.3

No Clock/Oscillator Source

When not in use, for low static IDD, add a pull-down resistor to XTAL1.

Figure 4-3. No Clock/Oscillator Connections

R_PD= 4.7 KΩ

XTAL2

NC

XTAL1

R_PD

GND

4.4.4

Timer Oscillator

For the timer oscillator pins, TOSC1 and TOSC2, the crystal is connected directly between the

pins. The oscillator is optimized for use with a 32.768 kHz watch crystal. An external clock signal

applied to this pin goes through the same amplifier having a bandwidth of 1 MHz. The external

clock signal should therefore be in the range

0 Hz – 1 MHz.

Figure 4-4. Time Oscillator Connections

C₁= 33 pF

C₂= 27 pF

R_B= 10M

R_S= 200K

R_S

C₁

C₂

TOSC2

TOSC1

R_B

42

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.5

Architectural Overview

The AVR uses a Harvard architecture concept – with separate memories and buses for program

and data. The program memory is accessed with a single level pipeline. While one instruction is

being executed, the next instruction is pre-fetched from the program memory. This concept

enables instructions to be executed in every clock-cycle. The program memory is in-system pro-

grammable SRAM memory. With a few exceptions, AVR instructions have a single 16-bit word

format, meaning that every program memory address contains a single 16-bit instruction.

During interrupts and subroutine calls, the return address program counter (PC) is stored on the

stack. The stack is effectively allocated in the general data SRAM, as a consequence, the stack

size is only limited by the total SRAM size and the usage of the SRAM. All user programs must

initialize the Stack Pointer (SP) in the reset routine (before subroutines or interrupts are exe-

cuted). The 16-bit stack pointer is read/write accessible in the I/O space.

The data SRAM can be easily accessed through the five different addressing modes supported

in the AVR architecture.

A flexible interrupt module has its control registers in the I/O space with an additional global

interrupt enable bit in the status register. All the different interrupts have a separate interrupt

vector in the interrupt vector table at the beginning of the program memory. The different inter-

rupts have priority in accordance with their interrupt vector position. The lower the interrupt

vector address, the higher the priority.

The memory spaces in the AVR architecture are all linear and regular memory maps.

43

1138H–FPSLI–6/05

4.6

General-purpose Register File

Figure 4-5 shows the structure of the 32 x 8 general-purpose working registers in the CPU.

Figure 4-5. AVR CPU General-purpose Working Registers

7

0

Addr.

$00

R0

R1

$01

R2

$02

. . .

R13

R14

R15

R16

R17

. . .

$0D

$0E

$0F

$10

$11

General-purpose

Working Registers

R26

R27

R28

R29

R30

R31

$1A

$1B

$1C

$1D

$1E

$1F

AVR X-register Low Byte

AVR X-register High Byte

AVR Y-register Low Byte

AVR Y-register High Byte

AVR Z-register Low Byte

AVR Z-register High Byte

All the register operating instructions in the instruction set have direct- and single-cycle access

to all registers. The only exception is the five constant arithmetic and logic instructions SBCI,

SUBI, CPI, ANDI and ORI between a constant and a register and the LDI instruction for load-

immediate constant data. These instructions apply to the second half of the registers in the reg-

ister file – R16..R31. The general SBC, SUB, CP, AND and OR and all other operations between

two registers or on a single-register apply to the entire register file.

As shown in Figure 4-5 each register is also assigned a data memory address, mapping the reg-

isters directly into the first 32 locations of the user Data Space. Although not being physically

implemented as SRAM locations, this memory organization provides great flexibility in access of

the registers, as the X, Y and Z registers can be set to index any register in the file.

The 4 to 16 Kbytes of data SRAM, as configured during FPSLIC download, are available for gen-

eral data are implemented starting at address $0060 as follows:

4 Kbytes

8 Kbytes

12 Kbytes

16 Kbytes

$0060 : $0FFF

$0060 : $1FFF

$0060 : $2FFF

$0060 : $3FFF

Addresses beyond the maximum amount of data SRAM are unavailable for write or read and will

return unknown data if accessed. Ghost memory is not implemented.

44

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.7

4.8

4.9

X-register, Y-register and Z-register

Registers R26..R31 have some added functions to their general-purpose usage. These registers

are address pointers for indirect addressing of the SRAM. The three indirect address registers X,

Y and Z have functions as fixed displacement, automatic increment and decrement (see the

descriptions for the different instructions).

ALU – Arithmetic Logic Unit

The high-performance AVR ALU operates in direct connection with all the 32 general-purpose

working registers. Within a single clock cycle, ALU operations between registers in the register

file are executed. The ALU operations are divided into three main categories – arithmetic, logical

and bit-functions.

Multiplier Unit

The high-performance AVR Multiplier operates in direct connection with all the 32 general-pur-

pose working registers. This unit performs 8 x 8 multipliers every two clock cycles. See multiplier

details on page 112.

4.10 SRAM Data Memory

External data SRAM (or program) cannot be used with the FPSLIC AT94K family.

The five different addressing modes for the data memory cover: Direct, Indirect with Displace-

ment, Indirect, Indirect with Pre-decrement and Indirect with Post-increment. In the register file,

registers R26 to R31 feature the indirect addressing pointer registers.

The Indirect with Displacement mode features a 63 address locations reach from the base

address given by the Y- or Z-register.

When using register indirect addressing modes with automatic Pre-decrement and Post-incre-

ment, the address registers X, Y and Z are decremented and incremented.

The entire data address space including the 32 general-purpose working registers and the 64

I/O registers are all accessible through all these addressing modes. See the next section for a

detailed description of the different addressing modes.

4.10.1

Program and Data Addressing Modes

The embedded AVR core supports powerful and efficient addressing modes for access to the

program memory (SRAM) and data memory (SRAM, Register File and I/O Memory). This sec-

tion describes the different addressing modes supported by the AVR architecture.

Register Direct, Single-register Rd

The operand is contained in register d (Rd).

Register Direct, Two Registers Rd and Rr

Operands are contained in register r (Rr) and d (Rd). The result is stored in register d (Rd).

I/O Direct

Operand address is contained in 6 bits of the instruction word. n is the destination or source reg-

ister address.

45

1138H–FPSLI–6/05

Data Direct

A 16-bit data address is contained in the 16 LSBs of a two-word instruction. Rd/Rr specify the

destination or source register.

Data Indirect with Displacement

Operand address is the result of the Y- or Z-register contents added to the address contained in

6 bits of the instruction word.

Data Indirect

Operand address is the contents of the X-, Y- or the Z-register.

Data Indirect with Pre-decrement

The X-, Y- or the Z-register is decremented before the operation. Operand address is the decre-

mented contents of the X, Y or the Z-register.

Data Indirect with Post-increment

The X-, Y- or the Z-register is incremented after the operation. The operand address is the con-

tent of the X-, Y- or the Z-register prior to incrementing.

Direct Program Address, JMP and CALL

Program execution continues at the address immediate in the instruction words.

Indirect Program Addressing, IJMP and ICALL

Program execution continues at address contained by the Z-register (i.e., the PC is loaded with

the contents of the Z-register).

Relative Program Addressing, RJMP and RCALL

Program execution continues at address PC + k + 1. The relative address k is -2048 to 2047.

4.10.2

Memory Access Times and Instruction Execution Timing

This section describes the general access timing concepts for instruction execution and internal

memory access.

The AVR CPU is driven by the XTAL1 input directly generated from the external clock crystal for

the chip. No internal clock division is used.

Figure 4-6 shows the parallel instruction fetches and instruction executions enabled by the Har-

vard architecture and the fast-access register file concept. This is the basic pipelining concept to

obtain up to 1 MIPS per MHz with the corresponding unique results for functions per cost, func-

tions per clocks and functions per power-unit.

46

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-6. The Parallel Instruction Fetches and Instruction Executions

T1

T2

T3

T4

AVR CLK

1st Instruction Fetch

1st Instruction Execute

2nd Instruction Fetch

2nd Instruction Execute

3rd Instruction Fetch

3rd Instruction Execute

4th Instruction Fetch

Figure 4-7 shows the internal timing concept for the register file. In a single clock cycle an ALU

operation using two register operands is executed, and the result is stored back to the destina-

tion register.

Figure 4-7. Single Cycle ALU Operation

T1

T2

T3

T4

AVR CLK

Total ExecutionTime

Register Operands Fetch

ALU Operation Execute

Result Write Back

The internal data SRAM access is performed in two system clock cycles as described in

Figure 4-8.

Figure 4-8. On-chip Data SRAM Access Cycles

T1

T2

T3

T4

AVR CLK

Address

Data

Prev. Address

Address

WR

Data

RD

47

1138H–FPSLI–6/05

4.11 Memory-mapped I/O

The I/O space definition of the embedded AVR core is shown in the following table:

4.11.1

AT94K Register Summary

Reference

Page

Address

Name

Bit 7

I

Bit 6

T

Bit 5

H

Bit 4

S

Bit 3

V

Bit 2

N

Bit 1

Z

Bit 0

C

$3F ($5F)

$3E ($5E)

$3D ($5D)

$3C ($5C)

$3B ($5B)

$3A ($5A)

$39 ($59)

$38 ($58)

$37 ($57)

$36 ($56)

$35 ($55)

$34 ($54)

$33 ($53)

$32 ($52)

$31 ($51)

$30 ($50)

$2F ($4F)

$2E ($4E)

$2D ($4D)

$2C ($4C)

$2B ($4B)

$2A ($4A)

$29 ($49)

$28 ($48)

$27 ($47)

$26 ($46)

$25 ($45)

$24 ($44)

$23 ($43)

$22 ($42)

$21 ($41)

$20 ($40)

$1F ($3F)

$1E ($3E)

$1D ($3D)

$1C ($3C)

$1B ($3B)

$1A ($3A)

$19 ($39)

$18 ($38)

$17 ($37)

SREG

51

57

51

SPH

SP15

SP7

SP14

SP6

SP13

SP5

SP12

SP4

SP11

SP3

SP10

SP2

SP9

SP1

SP8

SP0

SPL

Reserved

EIMF

INTF3

INTF2

INTF1

INTF0

INT3

FMXOR

TICIE1

ICF1

INT2

WDTS

OCIE2

OCF2

INT1

DBG

INT0

SRST

OCIE0

OCF0

62

51

62

63

SFTCR

TIMSK

TIFR

TOIE1

TOV1

OCIE1A

OCF1A

OCIE1B

OCF1B

TOIE2

TOV2

TOIE0

TOV0

Reserved

TWCR

MCUR

Reserved

TCCR0

TCNT0

OCR0

TWINT

JTRF

TWEA

JTD

TWSTA

SE

TWSTO

SM1

TWWC

SM0

TWEN

PORF

TWIE

110

51

WDRF

CS01

EXTRF

FOC0

PWM0

COM01

COM00

CTC0

CS02

CS00

69

70

Timer/Counter0 (8-bit)

Timer/Counter0 Output Compare Register

71

SFIOR

TCCR1A

TCCR1B

TCNT1H

TCNT1L

OCR1AH

OCR1AL

OCR1BH

OCR1BL

TCCR2

ASSR

PSR2

PWM11

CS11

PSR10

PWM10

CS10

66

COM1A1

ICNC1

COM1A0

ICES1

COM1B1

ICPE

COM1B0

FOC1A

CTC1

FOC1B

CS12

76

77

Timer/Counter1 - Counter Register High Byte

Timer/Counter1 - Counter Register Low Byte

78

Timer/Counter1 - Output Compare Register A High Byte

Timer/Counter1 - Output Compare Register A Low Byte

Timer/Counter1 - Output Compare Register B High Byte

Timer/Counter1 - Output Compare Register B Low Byte

79

FOC2

PWM2

COM21

COM20

CTC2

AS2

CS22

CS21

CS20

69

TCN20B

OCR2UB

TCR2UB

73

ICR1H

ICR1L

Timer/Counter1 - Input Capture Register High Byte

Timer/Counter1 - Input Capture Register Low Byte

Timer/Counter2 (8-bit)

80

TCNT2

OCR2

70

Timer/Counter 2 Output Compare Register

71

WDTCR

UBRRHI

TWDR

TWAR

WDTOE

WDE

WDP2

WDP1

WDP0

83

UART1 Baud Rate High Nibble [11..8]

2-wire Serial Data Register

UART0 Baud Rate Low Nibble [11..8]

105

111

112

109

52

2-wire Serial Address Register

TWSR

2-wire Serial Status Register

TWBR

2-wire Serial Bit Rate Register

FPGAD

FPGAZ

FPGAY

FPGAX

FISUD

FPGA Cache Data Register (D7 - D0)

FPGA Cache Z Address Register (T3 - T0) (Z3 - Z0)

FPGA Cache Y Address Register (Y7 - Y0)

FPGA Cache X Address Register (X7 - X0)

53

FPGA I/O Select, Interrupt Mask/Flag Register D (Reserved on AT94K05)

54, 56

48

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.11.1

AT94K Register Summary (Continued)

Reference

Address

Name

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Page

54, 56

53

$16 ($36)

$15 ($35)

$14 ($34)

$13 ($33)

$12 ($32)

$11 ($31)

$10 ($30)

$0F ($2F)

$0E ($2E)

$0D ($2D)

$0C ($2C)

$0B ($2B)

$0A ($2A)

$09 ($29)

FISUC

FPGA I/O Select, Interrupt Mask/Flag Register C (Reserved on AT94K05)

FPGA I/O Select, Interrupt Mask/Flag Register B

FPGA I/O Select, Interrupt Mask/Flag Register A

FIADR

FISUB

FISUA

FISCR

XFIS1

PORTD1

DDRD1

PIND1

XFIS0

PORTD0

DDRD0

PIND0

PORTD

DDRD

PORTD7

DDRD7

PIND7

PORTD6

DDRD6

PIND6

PORTD5

DDRD5

PIND5

PORTD4

DDRD4

PIND4

PORTD3

DDRD3

PIND3

PORTD2

DDRD2

PIND2

124

PIND

124

Reserved

UDR0

UART0 I/O Data Register

101

103

105

UCSR0A

UCSR0B

UBRR0

RXC0

TXC0

UDRE0

UDRIE0

FE0

OR0

U2X0

MPCM0

TXB80

RXCIE0

TXCIE0

RXEN0

TXEN0

CHR90

RXB80

UART0 Baud-rate Register

IDRD

OCDR

(Reserved)

$08 ($28)

Reserved⁽¹⁾

$07 ($27)

$06 ($26)

$05 ($25)

$04 ($24)

$03 ($23)

$02 ($22)

$01 ($21)

$00 ($20)

PORTE

DDRE

PORTE7

DDRE7

PINE7

PORTE6

DDRE6

PINE6

PORTE5

DDRE5

PINE5

PORTE4

DDRE4

PINE4

PORTE3

DDRE3

PINE3

PORTE2

DDRE2

PINE2

PORTE1

DDRE1

PINE1

PORTE0

DDRE0

PINE0

126

PINE

Reserved

UDR1

UART1 I/O Data Register

101

103

105

UCSR1A

UCSR1B

UBRR1

RXC1

TXC1

UDRE1

UDRIE1

FE1

OR1

U2X1

MPCM1

TXB81

RXCIE1

TXCIE1

RXEN1

TXEN1

CHR91

RXB81

UART1 Baud-rate Register

Note:

1. The On-chip Debug Register (OCDR) is detailed on the “FPSLIC On-chip Debug System” distributed within Atmel and select

third-party vendors only under Non-Disclosure Agreement (NDA). Contact fpslic@atmel.com for a copy of this document.

The embedded AVR core I/Os and peripherals, and all the virtual FPGA peripherals are placed

in the I/O space. The different I/O locations are directly accessed by the IN and OUT instructions

transferring data between the 32 x 8 general-purpose working registers and the I/O space. I/O

registers within the address range $00 – $1F are directly bit-accessible using the SBI and CBI

instructions. In these registers, the value of single bits can be checked by using the SBIS and

SBIC instructions. When using the I/O specific instructions IN, OUT, the I/O register address

$00 – $3F are used, see Figure 4-9. When addressing I/O registers as SRAM, $20 must be

added to this address. All I/O register addresses throughout this document are shown with the

SRAM address in parentheses.

49

1138H–FPSLI–6/05

Figure 4-9. Memory-mapped I/O

SRAM Space

$5F

I/O Space

Memory-mapped

I/O

$3F

$1F

$00

Registers r0 - r31

$00

Used for In/Out

Instructions

Used for all

Other Instructions

For single-cycle access (In/Out Commands) to I/O, the instruction has to be less than 16 bits:

opcode

register

address

r0 - 31 ($1F)

5 bits

r0 - 63 ($3F)

6 bits

5 bits

In the data SRAM, the registers are located at memory addresses $00 - $1F and the I/O space is

located at memory addresses $20 - $5F.

As there are only 6 bits available to refer to the I/O space, the address is re-mapped down 2 bits.

This means the In/Out commands access $00 to $3F which goes directly to the I/O and maps to

$20 to $5F in SRAM. All other instructions access the I/O space through the $20 - $5F

addressing.

For compatibility with future devices, reserved bits should be written zero if accessed. Reserved

I/O memory addresses should never be written.

The status flags are cleared by writing a logic 1 to them. Note that the CBI and SBI instructions

will operate on all bits in the I/O register, writing a one back into any flag read as set, thus clear-

ing the flag. The CBI and SBI instructions work with registers $00 to $1F only.

50

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Status Register – SREG

The AVR status register⁽¹⁾– SREG – at I/O space location $3F ($5F) is defined as:

BitM

7

6

5

4

3

2

1

0

$3F ($5F)

Read/Write

Initial Value

I

T

H

S

V

N

Z

C

SREG

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

Note:

1. Note that the status register is not automatically stored when entering an interrupt routine and

restored when returning from an interrupt routine. This must be handled by software.

• Bit 7 - I: Global Interrupt Enable

The global interrupt enable bit must be set (one) for the interrupts to be enabled. The individual

interrupt enable control is then performed in separate control registers. If the global interrupt

enable register is cleared (zero), none of the interrupts are enabled independent of the individual

interrupt enable settings. The I-bit is cleared by the hardware after an interrupt has occurred,

and is set by the RETI instruction to enable subsequent interrupts.

• Bit 6 - T: Bit Copy Storage

The bit copy instructions BLD (Bit LoaD) and BST (Bit STore) use the T-bit as source and desti-

nation for the operated bit. A bit from a register in the register file can be copied into T by the

BST instruction, and a bit in T can be copied into a bit in a register in the register file by the BLD

instruction.

• Bit 5 - H: Half-carry Flag

The half-carry flag H indicates a half-carry in some arithmetic operations.

• Bit 4 - S: Sign Bit, S = N

V

The S-bit is always an exclusive or between the negative flag N and the two’s complement over-

flow flag V.

• Bit 3 - V: Two’s Complement Overflow Flag

The two’s complement overflow flag V supports two’s complement arithmetics.

• Bit 2 - N: Negative Flag

The negative flag N indicates a negative result from an arithmetical or logical operation.

• Bit 1 - Z: Zero Flag

The zero flag Z indicates a zero result from an arithmetical or logical operation.

• Bit 0 - C: Carry Flag

The carry flag C indicates a carry in an arithmetical or logical operation.

51

1138H–FPSLI–6/05

Stack Pointer – SP

The general AVR 16-bit Stack Pointer is effectively built up of two 8-bit registers in the I/O space

locations $3E ($5E) and $3D ($5D). Future versions of FPSLIC may support up to 64K Bytes of

memory; therefore, all 16 bits are used.

Bit

15

14

13

12

11

10

9

8

$3E ($5E)

$3D ($5D)

SP15

SP7

7

SP14

SP6

6

SP13

SP5

5

SP12

SP4

4

SP11

SP3

3

SP10

SP2

2

SP9

SP1

1

SP8

SP0

0

SPH

SPL

Read/Write

Initial Value

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

The Stack Pointer points to the data SRAM stack area where the Subroutine and Interrupt

Stacks are located. This Stack space in the data SRAM must be defined by the program before

any subroutine calls are executed or interrupts are enabled. The stack pointer must be set to

point above $60. The Stack Pointer is decremented by one when data is pushed onto the Stack

with the PUSH instruction, and it is decremented by two when an address is pushed onto the

Stack with subroutine calls and interrupts. The Stack Pointer is incremented by one when data is

popped from the Stack with the POP instruction, and it is incremented by two when an address

is popped from the Stack with return from subroutine RET or return from interrupt RETI.

4.12 Software Control of System Configuration

The software control register will allow the software to manage select system level configuration

bits.

Software Control Register – SFTCR

Bit

7

-

6

-

5

-

4

-

3

2

1

0

$3A ($5A)

Read/Write

Initial Value

FMXOR

R/W

0

WDTS

R/W

0

DBG

R/W

0

SRST

R/W

0

SFTCR

R

0

R

0

R

0

R

0

• Bits 7..4 - Res: Reserved Bits

These bits are reserved in the AT94K and always read as zero.

• Bit 3 - FMXOR: Frame Mode XOR (Enable/Disable)

This bit is XORed with the System Control Register’s Enable Frame Interface bit. The behavior

when this bit is set to 1 is dependent on how the SCR was initialized. If the Enable Frame Inter-

face bit in the SCR is 0, the FMXOR bit enables the Frame Interface when set to 1. If the Enable

Frame Interface bit in the SCR is 1, the FMXOR bit disables the Frame Interface when set to 1.

During AVR reset, the FMXOR bit is cleared by the hardware.

• Bit 2 - WDTS: Software Watchdog Test Clock Select

When this bit is set to 1, the test clock signal is selected to replace the AVR internal oscillator

into the associated watchdog timer logic. During AVR reset, the WDTS bit is cleared by the

hardware.

• Bit 1 - DBG: Debug Mode

52

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

When this bit is set to 1, the AVR can write its own program SRAM. During AVR reset, the DBG

bit is cleared by the hardware.

• Bit 0 - SRST: Software Reset

When this bit is set (one), a reset request is sent to the system configuration external to the

AVR. Appropriate reset signals are generated back into the AVR and configuration download is

initiated. A software reset will cause the EXTRF bit in the MCUR register to be set (one), which

remains set throughout the AVR reset and may be read by the restarted program upon reset

complete. The external reset flag is set (one) since the requested reset is issued from the sys-

tem configuration external to the AVR core. During AVR reset, the SRST bit is cleared by the

hardware.

MCU Control Status/Register – MCUR

The MCU Register contains control bits for general MCU functions and status bits to indicate the

source of an MCU reset.

Bit

7

6

5

4

3

2

1

0

$35 ($55)

Read/Write

Initial Value

JTRF

R/W

0

JTD

R/W

0

SE

R/W

0

SM1

R/W

0

SM0

R/W

0

PORF

R/W

1

WDRF

R/W

0

EXTRF

R/W

1

MCUR

• Bit 7 - JTRF: JTAG Reset Flag

This flag is set (one) upon issuing the AVR_RESET ($C) JTAG instruction. The flag can only be

cleared (zero) by writing a zero to the JTRF bit or by a power-on reset. The bit will not be cleared

by hardware during AVR reset.

• Bit 6 - JTD: JTAG Disable

When this bit is cleared (zero), and the System Control Register JTAG Enable bit is set (one),

the JTAG interface is disabled. To avoid unintentional disabling or enabling of the JTAG inter-

face, a timed sequence must be followed when changing this bit: the application software must

write this bit to the desired value twice within four cycles to change its value.

• Bit 5 - SE: Sleep Enable

The SE bit must be set (one) to make the MCU enter the Sleep mode when the SLEEP instruc-

tion is executed. To avoid the MCU entering the Sleep mode unless it is the programmers

purpose, it is recommended to set the Sleep Enable SE bit just before the execution of the

SLEEP instruction.

• Bits 4, 3 - SM1/SM0: Sleep Mode Select Bits 1 and 0

This bit selects between the three available Sleep modes as shown in Table 4-3.

• Bit 2 - PORF: Power-on Reset Flag

This flag is set (one) upon power-up of the device. The flag can only be cleared (zero) by writing

a zero to the PORF bit. The bit will not be cleared by the hardware during AVR reset.

• Bit 1 - WDRF: Watchdog Reset Flag

This bit is set if a watchdog reset occurs. The bit is cleared by writing a logic 0 to the flag.

53

1138H–FPSLI–6/05

• Bit 0 - EXTRF: External (Software) Reset Flag

This flag is set (one) in three separate circumstances: power-on reset, use of Resetn/AVRRe-

setn and writing a one to the SRST bit in the Software Control Register – SFTCR. The PORF

flag can be checked to eliminate power-on reset as a cause for this flag to be set. There is no

way to differentiate between use of Resetn/AVRResetn and software reset. The flag can only be

cleared (zero) by writing a zero to the EXTRF bit. The bit will not be cleared by the hardware dur-

ing AVR reset.

Table 4-3.

Sleep Mode Select

SM1

SM0

Sleep Mode

Idle

0

1

0

1

0

1

Reserved

Power-down

Power-save

4.13 FPGA Cache Logic

FPGA Cache Data Register – FPGAD

Bit

7

6

5

4

3

2

1

0

$1B ($3B)

Read/Write

Initial Value

MSB

W

LSB

W

FPGAD

W

N/A

The FPGAD I/O Register address is not supported by a physical register; it is simply the I/O

address that, if written to, generates the FPGA Cache I/O write strobe. The CACHEIOWE signal

is a qualified version of the AVR IOWE signal. It will only be active if an OUT or ST (store to)

instruction references the FPGAD I/O address. The FPGAD I/O address is write-sensitive-only;

an I/O read to this location is ignored. If the AVR Cache Interface bit in the SCR [BIT62] is set

(one), the data being “written” to this address is cached to the FPGA address specified by the

FPGAX..Z registers (see below) during the active CACHEIOWE strobe.

FPGA Cache Z Address Registers – FPGAX..Z

Bit

7

6

5

4

3

2

1

0

$18 ($38)

$19 ($39)

$1A ($3A)

Read/Write

Initial Value

FCX7

FCY7

FCT3

R/W

0

FCX6

FCY6

FCT2

R/W

0

FCX5

FCY5

FCT1

R/W

0

FCX4

FCY4

FCT0

R/W

0

FCX3

FCY3

FCZ3

R/W

0

FCX2

FCY2

FCZ2

R/W

0

FCX1

FCY1

FCZ1

R/W

0

FCX0

FCY0

FCZ0

R/W

0

FPGAX

FPGAY

FPGAZ

The three FPGA Cache address registers combine to form the 24-bit address, CAC-

HEADDR[23:0], delivered to the FPGA cache logic outside the AVR block during a write to the

FPGAD I/O Register (see above).

54

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.14 FPGA I/O Selection by AVR

Sixteen select signals are sent to the FPGA for I/O addressing. These signals are decoded from

four I/O registry addresses (FISUA...D) and extended to sixteen with two bits from the FPGA I/O

Select Control Register (FISCR). In addition, the FPGAIORE and FPGAIOWE signals are quali-

fied versions of the IORE and IOWE signals. Each will only be active if one of the four base I/O

addresses are referenced. It is necessary for the FPGA design to implement any required regis-

ters for each select line; each qualified with either the FPGAIORE or FPGAIOWE strobe. Refer

to the FPGA/AVR Interface section for more details. Only the FISCR registers physically exist.

The FISUA...D I/O addresses for the purpose of FPGA I/O selection are NOT supported by AVR

Core I/O space registers; they are simply I/O addresses (available to 1 cycle IN/OUT instruc-

tions) which trigger appropriate enabling of the FPGA select lines and the FPGA IORE/IOWE

strobes (see Figure 3-1 on page 21).

FPGA I/O Select Control Register – FISCR

Bit

7

6

-

5

-

4

-

3

-

2

-

1

0

$13 ($33)

Read/Write

Initial Value

FIADR

R/W

0

XFIS1

R/W

0

XFIS0

R/W

0

FISCR

R

0

R

0

R

0

R

0

R

0

• Bit 7 - FIADR: FPGA Interrupt Addressing Enable

When FIADR is set (one), the four dual-purpose I/O addresses, FISUA..D, are mapped to four

physical registers that provide memory space for FPGA interrupt masking and interrupt flag sta-

tus. When FIADR is cleared (zero), an I/O read or write to one of the four dual-purpose I/O

addresses, FISUA..D, will access its associated group of four FPGA I/O select lines. The XFIS1

and XFIS0 bits (see Table 4-4) further determine which one select line in the accessed group is

set (one). A read will assign the FPGA I/O read enable to the AVR I/O read enable (FPGAIORE

← IORE) and a write, the FPGA I/O write enable to the AVR I/O write enable (FPGAIOWE ←

IOWE). FPGA macros utilizing one or more FPGA I/O select lines must use the FPGA I/O

read/write enables, FPGAIORE or FPGAIOWE, to qualify each select line. The FIADR bit

will be cleared (zero) during AVR reset.

• Bits 6..2 - Res: Reserved Bits

These bits are reserved and always read as zero.

• Bits 1, 0 - XFIS1, 0: Extended FPGA I/O Select Bits 1, 0

XFIS[1:0] determines which one of the four FPGA I/O select lines will be set (one) within the

accessed group. An I/O read or write to one of the four dual-purpose I/O addresses, FISUA..D,

will access one of four groups. Table 4-4 details the FPGA I/O selection scheme.

55

1138H–FPSLI–6/05

Table 4-4.

FPGA I/O Select Line Scheme

FISCR Register

FPGA I/O Select Lines

Read or Write

I/O Address

XFIS1

XFIS0

15..12

0000

0001

0010

0100

1000

11..8

0000

0001

0010

0100

1000

0000

7..4

3..0

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0000

0001

0010

0100

1000

0000

0001

0010

0100

1000

0000

FISUA $14 ($34)

FISUB $15 ($35)

FISUC $16 ($36)⁽¹⁾

FISUD $17 ($37)⁽¹⁾

Note:

1. Not available on AT94K05.

In summary, 16 select signals are sent to the FPGA for I/O addressing. These signals are

decoded from four base I/O Register addresses (FISUA..D) and extended to 16 with two bits

from the FPGA I/O Select Control Register, XFIS1 and XFIS0. The FPGA I/O read and write sig-

nals, FPGAIORE and FPGAIOWE, are qualified versions of the AVR IORE and IOWE signals.

Each will only be active if one of the four base I/O addresses is accessed.

Reset: all select lines become active and an FPGAIOWE strobe is enabled. This is to allow the

FPGA design to load zeros (8’h00) from the D-bus into appropriate registers.

56

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.14.1

General AVR/FPGA I/O Select Procedure

I/O select depends on the FISCR register setup and the FISUA..D register written to or read

from.

The following FISCR setups and writing data to the FISUA..D registers will result in the shown

I/O select lines and data presented on the 8-bit AVR–FPGA data bus.

Table 4-5.

FISCR Register Setups and I/O Select Lines.

FISCR Register

I/O Select Lines⁽¹⁾

FIADR(b7)

b6-2

XFIS1(b1)

XFIS0(b0)

FISUA

IOSEL 0

IOSEL 1

IOSEL 2

IOSEL 3

FISUB

FISUC

IOSEL 8

IOSEL 9

IOSEL 10

IOSEL 11

FISUD

0

-

0

1

0

1

0

1

IOSEL 4

IOSEL 5

IOSEL 6

IOSEL 7

IOSEL 12

IOSEL 13

IOSEL 14

IOSEL 15

Note:

1. IOSEL 15..8 are not available on AT94K05.

;---------------------------------------------

io_select0_write:

ldi r16,0x00

out FISCR,r16

out FISUA,r17;

;FIADR=0,XFIS1=0,XFIS0=0 ->I/O select line=0

;load I/O select values into FISCR register

;select line 0 high. Place data on AVR<->FPGA bus

; from r17 register. (out going data is assumed

; to be present in r17 before calling this subroutine)

ret

;---------------------------------------------

io_select13_read:

ldi r16,0x01

out FISCR,r16

in r18,FISUD

;FIADR=0,XFIS1=0,XFIS0=1 ->I/O select line=13

;load I/O select values into FISCR register

;select line 13 high. Read data on AVR<->FPGA bus

;which was placed into register FISUD.

ret

57

1138H–FPSLI–6/05

Figure 4-10. Out Instruction – AVR Writing to the FPGA

AVR INST

AVR CLOCK

AVR IOWE

OUT INSTRUCTION

AVR IOADR

(FISUA, B, C or D)

AVR DBUS

WRITE DATA VALID

(FPGA DATA IN)

FPGA IOWE

FPGA I/O

SELECT "n"

FPGA CLOCK

(SET TO AVR

(1)

SYSTEM CLOCK)

Note:

1. AVR expects Write to be captured by the FPGA upon posedge of the AVR clock.

Figure 4-11. In Instruction – AVR Reading FPGA

AVR INST

AVR CLOCK

AVR IORE

IN INSTRUCTION

(1)

(2)

AVR IOADR

(FISUA, B, C or D)

AVR DBUS

READ DATA VALID

(FPGA DATA OUT)

FPGA IORE

FPGA I/O

SELECT "n"

Notes: 1. AVR captures read data upon posedge of the AVR clock.

2. At the end of an FPGA read cycle, there is a chance for the AVR data bus contention between

the FPGA and another peripheral to start to drive (active IORE at new address versus

FPGAIORE + Select “n”), but since the AVR clock would have already captured the data from

AVR DBUS (= FPGA Data Out), this is a “don’t care” situation.

58

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.15 FPGA I/O Interrupt Control by AVR

This is an alternate memory space for the FPGA I/O Select addresses. If the FIADR bit in the

FISCR register is set to logic 1, the four I/O addresses, FISUA - FISUD, are mapped to physical

registers and provide memory space for FPGA interrupt masking and interrupt flag status. If the

FIADR bit in the FISCR register is cleared to a logic 0, the I/O register addresses will be

decoded into FPGA select lines.

All FPGA interrupt lines into the AVR are negative edge triggered. See page 60 for interrupt

priority.

Interrupt Control Registers – FISUA..D

Bit

7

6

5

4

3

2

1

0

$14 ($34)

$15 ($35)

$16 ($36)

$17 ($37)

Read/Write

Initial Value

FIF3

FIF7

FIF11

FIF15

R/W

0

FIF2

FIF6

FIF10

FIF14

R/W

0

FIF1

FIF5

FIF9

FIF13

R/W

0

FIF0

FIF4

FIF8

FIF12

R/W

0

FINT3

FINT7

FINT11

FINT15

R/W

FINT2

FINT6

FINT10

FINT14

R/W

FINT1

FINT5

FINT9

FINT13

R/W

0

FINT0

FINT4

FINT8

FINT12

R/W

0

FISUA

FSUB

FISUC

FISUD

0

• Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0

The 16 FPGA interrupt flag bits all work the same. Each is set (one) by a valid negative edge

transition on its associated interrupt line from the FPGA. Valid transitions are defined as any

change in state preceded by at least two cycles of the old state and succeeded by at least two

cycles of the new state. Therefore, it is required that interrupt lines transition from 1 to 0 at

least two cycles after the line is stable High; the line must then remain stable Low for at

least two cycles following the transition. Each bit is cleared by the hardware when executing

the corresponding interrupt handling vector. Alternatively, each bit will be cleared by writing a

logic 1 to it. When the I-bit in the Status Register, the corresponding FPGA interrupt mask bit

and the given FPGA interrupt flag bit are set (one), the associated interrupt is executed.

• Bits 7..4 - FIF7 - 4: FPGA Interrupt Flags 7 - 4

See Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0.

• Bits 7..4 - FIF11 - 8: FPGA Interrupt Flags 11 - 8

See Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0. Not available on the AT94K05.

• Bits 7..4 - FIF15 - 12: FPGA Interrupt Flags 15 - 12

See Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0. Not available on the AT94K05.

• Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0⁽¹⁾

The 16 FPGA interrupt mask bits all work the same. When a mask bit is set (one) and the I-bit in

the Status Register is set (one), the given FPGA interrupt is enabled. The corresponding inter-

rupt handling vector is executed when the given FPGA interrupt flag bit is set (one) by a negative

edge transition on the associated interrupt line from the FPGA.

Note:

1. FPGA interrupts 3 - 0 will cause a wake-up from the AVR Sleep modes. These interrupts are

treated as low-level triggered in the Power-down and Power-save modes, see “Sleep Modes”

on page 69.

• Bits 3..0 - FINT7 - 4: FPGA Interrupt Masks 7 - 4

See Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0.

59

1138H–FPSLI–6/05

• Bits 3..0 - FINT11 - 8: FPGA Interrupt Masks 11 - 8

See Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0. Not available on the AT94K05.

• Bits 3..0 - FINT15 - 12: FPGA Interrupt Masks 15 -12

See Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0. Not available on the AT94K05.

4.16 Reset and Interrupt Handling

The embedded AVR and FPGA core provide 35 different interrupt sources. These interrupts and

the separate reset vector each have a separate program vector in the program memory space.

All interrupts are assigned individual enable bits (masks) which must be set (one) together with

the I-bit in the status register in order to enable the interrupt.

The lowest addresses in the program memory space must be defined as the Reset and Interrupt

vectors. The complete list of vectors is shown in Table 4-6. The list also determines the priority

levels of the different interrupts. The lower the address the higher the priority level. RESET has

the highest priority, and next is FPGA_INT0 – the FPGA Interrupt Request 0 etc.

Table 4-6.

Vector No.

Reset and Interrupt Vectors

Program

(hex)

Address

Source

Interrupt Definition

Reset Handle: Program

Execution Starts Here

01

$0000

RESET

02

03

04

05

06

07

08

09

$0002

$0004

$0006

$0008

$000A

$000C

$000E

$0010

FPGA_INT0

EXT_INT0

FPGA_INT1

EXT_INT1

FPGA_INT2

EXT_INT2

FPGA_INT3

EXT_INT3

FPGA Interrupt0 Handle

External Interrupt0 Handle

FPGA Interrupt1 Handle

External Interrupt1 Handle

FPGA Interrupt2 Handle

External Interrupt2 Handle

FPGA Interrupt3 Handle

External Interrupt3 Handle

Timer/Counter2 Compare

Match Interrupt Handle

0A

0B

0C

0D

0E

0F

10

$0012

$0014

$0016

$0018

$001A

$001C

$001E

TIM2_COMP

TIM2_OVF

Timer/Counter2 Overflow

Interrupt Handle

Timer/Counter1 Capture

Event Interrupt Handle

TIM1_CAPT

TIM1_COMPA

TIM1_COMPB

TIM1_OVF

Timer/Counter1 Compare

Match A Interrupt Handle

Timer/Counter1 Compare

Match B Interrupt Handle

Timer/Counter1 Overflow

Interrupt Handle

Timer/Counter0 Compare

Match Interrupt Handle

TIM0_COMP

60

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 4-6.

Vector No.

Reset and Interrupt Vectors (Continued)

Program

Address

(hex)

Source

Interrupt Definition

Timer/Counter0 Overflow

Interrupt Handle

11

$0020

TIM0_OVF

12

13

14

15

$0022

$0024

$0026

$0028

FPGA_INT4

FPGA_INT5

FPGA_INT6

FPGA_INT7

FPGA Interrupt4 Handle

FPGA Interrupt5 Handle

FPGA Interrupt6 Handle

FPGA Interrupt7 Handle

UART0 Receive Complete

Interrupt Handle

16

17

18

19

1A

1B

1C

1D

1E

1F

20

21

22

$002A

$002C

$002E

$0030

$0032

$0034

$0036

$0038

$003A

$003C

$003E

$0040

$0042

UART0_RXC

UART0_DRE

UART0_TXC

FPGA_INT8

FPGA_INT9

FPGA_INT10

FPGA_INT11

UART1_RXC

UART1_DRE

UART1_TXC

FPGA_INT12

FPGA_INT13

FPGA_INT14

UART0 Data Register Empty

Interrupt Handle

UART0 Transmit Complete

Interrupt Handle

FPGA Interrupt8 Handle

(not available on AT94K05)

FPGA Interrupt9 Handle

(not available on AT94K05)

FPGA Interrupt10 Handle

(not available on AT94K05)

FPGA Interrupt11 Handle

(not available on AT94K05)

UART1 Receive Complete

Interrupt Handle

UART1 Data Register Empty

Interrupt Handle

UART1 Transmit Complete

Interrupt Handle

FPGA Interrupt12 Handle

(not available on AT94K05)

FPGA Interrupt13 Handle

(not available on AT94K05)

FPGA Interrupt14 Handle

(Not Available on AT94K05)

FPGA Interrupt15 Handle

(not available on AT94K05)

23

24

$0044

$0046

FPGA_INT15

TWS_INT

2-wire Serial Interrupt

61

1138H–FPSLI–6/05

The most typical program setup for the Reset and Interrupt Vector Addresses are:

Address Labels

Code

Comments

$0000

$0002

$0004

$0006

$0008

$000A

$000C

$000E

$0010

$0012

$0014

$0016

$0018

$001A

$001C

$001E

$0020

$0022

$0024

$0026

$0028

$002A

$002C

$002E

$0030

$0032

$0034

$0036

$0038

$003A

$003C

$003E

$0040

$0042

$0044

$0046

;

jmp

RESET

Reset Handle: Program Execution Starts Here

; FPGA Interrupt0 Handle

FPGA_INT0

EXT_INT0

FPGA_INT1

EXT_INT1

FPGA_INT2

EXT_INT2

FPGA_INT3

EXT_INT3

TIM2_COMP

TIM2_OVF

TIM1_CAPT

TIM1_COMPA

TIM1_COMPB

TIM1_OVF

TIM0_COMP

TIM0_OVF

FPGA_INT4

FPGA_INT5

FPGA_INT6

FPGA_INT7

UART0_RXC

UART0_DRE

UART0_TXC

FPGA_INT8

FPGA_INT9

FPGA_INT10

FPGA_INT11

UART1_RXC

UART1_DRE

UART1_TXC

FPGA_INT12

FPGA_INT13

FPGA_INT14

FPGA_INT15

TWS_INT

; External Interrupt0 Handle

; FPGA Interrupt1 Handle

; External Interrupt1 Handle

; FPGA Interrupt2 Handle

; External Interrupt2 Handle

; FPGA Interrupt3 Handle

; External Interrupt3 Handle

; Timer/Counter2 Compare Match Interrupt Handle

; Timer/Counter2 Overflow Interrupt Handle

; Timer/Counter1 Capture Event Interrupt Handle

; Timer/Counter1 Compare Match A Interrupt Handle

; Timer/Counter1 Compare Match B Interrupt Handle

; Timer/Counter1 Overflow Interrupt Handle

; Timer/Counter0 Compare Match Interrupt Handle

; Timer/Counter0 Overflow Interrupt Handle

; FPGA Interrupt4 Handle

; FPGA Interrupt5 Handle

; FPGA Interrupt6 Handle

; FPGA Interrupt7 Handle

; UART0 Receive Complete Interrupt Handle

; UART0 Data Register Empty Interrupt Handle

; UART0 Transmit Complete Interrupt Handle

; FPGA Interrupt8 Handle⁽¹⁾

; FPGA Interrupt9 Handle⁽¹⁾

; FPGA Interrupt10 Handle⁽¹⁾

; FPGA Interrupt11 Handle⁽¹⁾

; UART1 Receive Complete Interrupt Handle

; UART1 Data Register Empty Interrupt Handle

; UART1 Transmit Complete Interrupt Handle

; FPGA Interrupt12 Handle⁽¹⁾

; FPGA Interrupt13 Handle⁽¹⁾

; FPGA Interrupt14 Handle⁽¹⁾

; FPGA Interrupt15 Handle⁽¹⁾

; 2-wire Serial Interrupt

RESET:

$0048

$0049

$004A

$004B

$004C

...

ldi

r16,high(RAMEND) ; Main program start

out

SPH,r16

r16,low(RAMEND)

SPL,r16

xxx

ldi

out

<instr>

...

Note:

1. Not Available on AT94K05. However, the vector jump table positions must be maintained for

appropriate UART and 2-wire serial interrupt jumps.

62

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.16.1

Reset Sources

The embedded AVR core has five sources of reset:

• External Reset. The MCU is reset immediately when a low-level is present on the RESET or

AVR RESET pin.

• Power-on Reset. The MCU is reset upon chip power-up and remains in reset until the FPGA

configuration has entered Idle mode.

• Watchdog Reset. The MCU is reset when the Watchdog Timer period expires and the

watchdog is enabled.

• Software Reset. The MCU is reset when the SRST bit in the Software Control register is set

(one).

• JTAG AVR Reset. The MCU is reset as long as there is a logic one in the Reset Register, one

of the scan chains of the JTAG system. See “IEEE 1149.1 (JTAG) Boundary-scan” on page

76.

During reset, all I/O registers except the MCU Status register are then set to their Initial Values,

and the program starts execution from address $0000. The instruction placed in address $0000

must be a JMP – absolute jump instruction to the reset handling routine. If the program never

enables an interrupt source, the interrupt vectors are not used, and regular program code can be

placed at these locations. The circuit diagram in Figure 4-12 shows the reset logic. Table 4-7

defines the timing and electrical parameters of the reset circuitry.

Figure 4-12. Reset Logic

DATA BUS

MCU STATUS

POR

FPGA

CONFIG

LOGIC

RESET/

AVR RESET

INTERNAL

RESET

S

Q

SFTCR

BIT 0

WATCHDOG

JTAG RESET

REGISTER

TIMER

FULL

R

INTERNAL

OSCILLATOR

DELAY COUNTERS

SYSTEM

CLOCK

SEL [4:0] CONTROLLED

BY FPGA CONFIGURATION

63

1138H–FPSLI–6/05

Table 4-7.

Symbol

Reset Characteristics (V_CC= 3.3V)

Parameter

Minimum

Typical

Maximum

Units

Power-on Reset Threshold

(Rising)

1.0

0.4

1.4

1.8

V

V_POT(1)

Power-on Reset Threshold

(Falling)

0.6

0.8

V

RESET Pin Threshold

Voltage

V_RST

V_CC/2

CPU

cycles

5

T_TOUT

Reset Delay Time-out Period

0.4

3.2

0.5

4.0

0.6

4.8

ms

12.8

16.0

19.2

Note:

Power-on Reset

1. The Power-on Reset will not work unless the supply voltage has been below V_POT(falling).

4.16.2

A Power-on Reset (POR) circuit ensures that the device is reset from power-on. As shown in

Figure 4-12, an internal timer clocked from the Watchdog Timer oscillator prevents the MCU

from starting until after a certain period after V_CChas reached the Power-on Threshold voltage –

V

_POT, regardless of the V_CCrise time (see Figure 4-13 and Figure 4-14).

Figure 4-13. MCU Start-up, RESET Tied to V_CC

V_POT

V_CC

V_RST

RESET

TIME-OUT

t_TOUT

INTERNAL RESET

Figure 4-14. Watchdog Reset during Operation

V_CC(HIGH)

RESET (HIGH)

1 XTAL CYCLE

WDT TIME-OUT

t_TOUT

RESET TIME-OUT

INTERNAL RESET

64

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

The MCU after five CPU clock-cycles, and can be used when an external clock signal is applied

to the XTAL1 pin. This setting does not use the WDT oscillator, and enables very fast start-up

from the Sleep, Power-down or Power-save modes if the clock signal is present during sleep.

RESET can be connected to V_CCdirectly or via an external pull-up resistor. By holding the pin

Low for a period after V_CChas been applied, the Power-on Reset period can be extended. Refer

to Figure 4-15 for a timing example on this.

Figure 4-15. MCU Start-up, RESET Controlled Externally

V_CC

V_POT

V_RST

RESET

t_TOUT

TIME-OUT

INTERNAL RESET

4.16.3

4.16.4

External Reset

An external reset is generated by a low-level on the AVRRESET pin. When the applied signal

reaches the Reset Threshold Voltage – V_RST– on its positive edge, the delay timer starts the

MCU after the Time-out period t_TOUThas expired.

Watchdog Reset

When the Watchdog times out, it will generate a short reset pulse of 1 XTAL cycle duration. On

the falling edge of this pulse, the delay timer starts counting the Time-out period t_TOUT. Time-out

period t_TOUTis approximately 3 µs – at V_CC= 3.3V. the period of the time out is voltage

dependent.

4.16.5

4.16.6

Software Reset

See “Software Control of System Configuration” on page 52.

Interrupt Handling

The embedded AVR core has one dedicated 8-bit Interrupt Mask control register: TIMSK –

Timer/Counter Interrupt Mask Register. In addition, other enable and mask bits can be found in

the peripheral control registers.

When an interrupt occurs, the Global Interrupt Enable I-bit is cleared (zero) and all interrupts are

disabled. The user software can set (one) the I-bit to enable nested interrupts. The I-bit is set

(one) when a Return from Interrupt instruction (RETI) is executed.

When the Program Counter is vectored to the actual interrupt vector in order to execute the

interrupt handling routine, the hardware clears the corresponding flag that generated the inter-

rupt. Some of the interrupt flags can also be cleared by writing a logic 1 to the flag bit position(s)

to be cleared.

65

1138H–FPSLI–6/05

If an interrupt condition occurs when the corresponding interrupt enable bit is cleared (zero), the

interrupt flag will be set and remembered until the interrupt is enabled, or the flag is cleared by

software.

If one or more interrupt conditions occur when the global interrupt enable bit is cleared (zero),

the corresponding interrupt flag(s) will be set and remembered until the global interrupt enable

bit is set (one), and will be executed by order of priority.

The status register is not automatically stored when entering an interrupt routine and restored

when returning from an interrupt routine. This must be handled by software.

External Interrupt Mask/Flag Register – EIMF

Bit

7

6

5

4

3

2

1

0

$3B ($5B)

Read/Write

Initial Value

INTF3

R/W

0

INTF2

R/W

0

INTF1

R/W

0

INTF0

R/W

0

INT3

R/W

0

INT2

R/W

0

INT1

R/W

0

INT0

R/W

0

EIMF

• Bits 3..0 - INT3, 2, 1, 0: External Interrupt Request 3, 2, 1, 0 Enable

When an INT3 - INT0 bit is set (one) and the I-bit in the Status Register (SREG) is set (one), the

corresponding external pin interrupt is enabled. The external interrupts are always negative

edge triggered interrupts, see “Sleep Modes” on page 69.

• Bits 7..4 - INTF3, 2, 1, 0: External Interrupt 3, 2, 1, 0 Flags

When a falling edge is detected on the INT3, 2, 1, 0 pins, an interrupt request is triggered. The

corresponding interrupt flag, INTF3, 2, 1, 0 becomes set (one). If the I-bit in SREG and the cor-

responding interrupt enable bit, INT3, 2, 1, 0 in EIMF, are set (one), the MCU will jump to the

interrupt vector. The flag is cleared when the interrupt routine is executed. Alternatively, the flag

is cleared by writing a logic 1 to it.

Timer/Counter Interrupt Mask Register – TIMSK

Bit

7

6

5

4

3

2

1

0

$39 ($39)

Read/Write

Initial Value

TOIE1

R/W

0

OCIE1A OCIE1B TOIE2

TICIE1

R/W

0

OCIE2

R/W

0

TOIE0

R/W

0

OCIE0

R/W

0

TIMSK

R/W

0

R/W

0

R/W

0

• Bit 7 - TOIE1: Timer/Counter1 Overflow Interrupt Enable

When the TOIE1 bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter1 Overflow interrupt is enabled. The corresponding interrupt is executed if an

overflow in Timer/Counter1 occurs, i.e., when the TOV1 bit is set in the Timer/Counter Interrupt

Flag Register – TIFR.

• Bit 6 - OCIE1A: Timer/Counter1 Output CompareA Match Interrupt Enable

When the OCIE1A bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter1 CompareA Match interrupt is enabled. The corresponding interrupt is executed

if a CompareA match in Timer/Counter1 occurs, i.e., when the OCF1A bit is set in the

Timer/Counter Interrupt Flag Register – TIFR.

66

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

• Bit 5 - OCIE1B: Timer/Counter1 Output CompareB Match Interrupt Enable

When the OCIE1B bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter1 CompareB Match interrupt is enabled. The corresponding interrupt is executed

if a CompareB match in Timer/Counter1 occurs, i.e., when the OCF1B bit is set in the

Timer/Counter Interrupt Flag Register – TIFR.

• Bit 4 - TOIE2: Timer/Counter2 Overflow Interrupt Enable

When the TOIE2 bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter2 overflow interrupt is enabled. The corresponding interrupt is executed if an over-

flow in Timer/Counter2 occurs, i.e., when the TOV2 bit is set in the Timer/Counter interrupt flag

register – TIFR.

• Bit 3 - TICIE1: Timer/Counter1 Input Capture Interrupt Enable

When the TICIE1 bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter1 input capture event interrupt is enabled. The corresponding interrupt is exe-

cuted if a capture-triggering event occurs on pin 29, (IC1), i.e., when the ICF1 bit is set in the

Timer/Counter interrupt flag register – TIFR.

• Bit 2 - OCIE2: Timer/Counter2 Output Compare Interrupt Enable

When the OCIE2 bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter2 Compare Match interrupt is enabled. The corresponding interrupt is executed if

a Compare match in Timer/Counter2 occurs, i.e., when the OCF2 bit is set in the Timer/Counter

interrupt flag register – TIFR.

• Bit 1 - TOIE0: Timer/Counter0 Overflow Interrupt Enable

When the TOIE0 bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter0 Overflow interrupt is enabled. The corresponding interrupt is executed if an

overflow in Timer/Counter0 occurs, i.e., when the TOV0 bit is set in the Timer/Counter Interrupt

Flag Register – TIFR.

• Bit 0 - OCIE0: Timer/Counter0 Output Compare Interrupt Enable

When the OCIE0 bit is set (one) and the I-bit in the Status Register is set (one), the

Timer/Counter0 Compare Match interrupt is enabled. The corresponding interrupt is executed if

a Compare match in Timer/Counter0 occurs, i.e., when the OCF0 bit is set in the Timer/Counter

Interrupt Flag Register – TIFR.

Timer/Counter Interrupt Flag Register – TIFR

Bit

7

6

5

4

3

2

1

0

$38 ($58)

Read/Write

Initial Value

TOV1

R/W

0

OCF1A

R/W

0

OCF1B

R/W

0

TOV2

R/W

0

ICF1

R/W

0

OCF2

R/W

0

TOV0

R/W

0

OCF0

R/W

0

TIFR

• Bit 7 - TOV1: Timer/Counter1 Overflow Flag

The TOV1 is set (one) when an overflow occurs in Timer/Counter1. TOV1 is cleared by the hard-

ware when executing the corresponding interrupt handling vector. Alternatively, TOV1 is cleared

by writing a logic 1 to the flag. When the I-bit in SREG, and TOIE1 (Timer/Counter1 Overflow

Interrupt Enable), and TOV1 are set (one), the Timer/Counter1 Overflow Interrupt is executed. In

PWM mode, this bit is set when Timer/Counter1 advances from $0000.

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• Bit 6 - OCF1A: Output Compare Flag 1A

The OCF1A bit is set (one) when compare match occurs between the Timer/Counter1 and the

data in OCR1A – Output Compare Register 1A. OCF1A is cleared by the hardware when exe-

cuting the corresponding interrupt handling vector. Alternatively, OCF1A is cleared by writing a

logic 1 to the flag. When the I-bit in SREG, and OCIE1A (Timer/Counter1 Compare Interrupt

Enable), and the OCF1A are set (one), the Timer/Counter1 Compare A match Interrupt is

executed.

• Bit 5 - OCF1B: Output Compare Flag 1B

The OCF1B bit is set (one) when compare match occurs between the Timer/Counter1 and the

data in OCR1B – Output Compare Register 1B. OCF1B is cleared by the hardware when exe-

cuting the corresponding interrupt handling vector. Alternatively, OCF1B is cleared by writing a

logic 1 to the flag. When the I-bit in SREG, and OCIE1B (Timer/Counter1 Compare match Inter-

rupt Enable), and the OCF1B are set (one), the Timer/Counter1 Compare B match Interrupt is

executed.

• Bit 4 - TOV2: Timer/Counter2 Overflow Flag

The TOV2 bit is set (one) when an overflow occurs in Timer/Counter2. TOV2 is cleared by the

hardware when executing the corresponding interrupt handling vector. Alternatively, TOV2 is

cleared by writing a logic 1 to the flag. When the I-bit in SREG, and TOIE2 (Timer/Counter1

Overflow Interrupt Enable), and TOV2 are set (one), the Timer/Counter2 Overflow Interrupt is

executed. In PWM mode, this bit is set when Timer/Counter2 advances from $00.

• Bit 3 - ICF1: Input Capture Flag 1

The ICF1 bit is set (one) to flag an input capture event, indicating that the Timer/Counter1 value

has been transferred to the input capture register – ICR1. ICF1 is cleared by the hardware when

executing the corresponding interrupt handling vector. Alternatively, ICF1 is cleared by writing a

logic 1 to the flag. When the SREG I-bit, and TICIE1 (Timer/Counter1 Input Capture Interrupt

Enable), and ICF1 are set (one), the Timer/Counter1 Capture Interrupt is executed.

• Bit 2 - OCF2: Output Compare Flag 2

The OCF2 bit is set (one) when compare match occurs between Timer/Counter2 and the data in

OCR2 – Output Compare Register 2. OCF2 is cleared by the hardware when executing the cor-

responding interrupt handling vector. Alternatively, OCF2 is cleared by writing a logic 1 to the

flag. When the I-bit in SREG, and OCIE2 (Timer/Counter2 Compare Interrupt Enable), and the

OCF2 are set (one), the Timer/Counter2 Output Compare Interrupt is executed.

• Bit 1 - TOV0: Timer/Counter0 Overflow Flag

The TOV0 bit is set (one) when an overflow occurs in Timer/Counter0. TOV0 is cleared by the

hardware when executing the corresponding interrupt handling vector. Alternatively, TOV0 is

cleared by writing a logic 1 to the flag. When the SREG I-bit, and TOIE0 (Timer/Counter0 Over-

flow Interrupt Enable), and TOV0 are set (one), the Timer/Counter0 Overflow interrupt is

executed. In PWM mode, this bit is set when Timer/Counter0 advances from $00.

• Bit 0 - OCF0: Output Compare Flag 0

The OCF0 bit is set (one) when compare match occurs between Timer/Counter0 and the data in

OCR0 – Output Compare Register 0. OCF0 is cleared by the hardware when executing the cor-

responding interrupt handling vector. Alternatively, OCF0 is cleared by writing a logic 1 to the

flag. When the I-bit in SREG, and OCIE0 (Timer/Counter2 Compare Interrupt Enable), and the

OCF0 are set (one), the Timer/Counter0 Output Compare Interrupt is executed.

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4.16.7

Interrupt Response Time

The interrupt execution response for all the enabled AVR interrupts is four clock cycles mini-

mum. Four clock cycles after the interrupt flag has been set, the program vector address for the

actual interrupt handling routine is executed. During this four clock-cycle period, the Program

Counter (2 bytes) is pushed onto the Stack, and the Stack Pointer is decremented by 2. The

vector is normally a jump to the interrupt routine, and this jump takes three clock cycles. If an

interrupt occurs during execution of a multi-cycle instruction, this instruction is completed before

the interrupt is serviced.

A return from an interrupt handling routine (same as for a subroutine call routine) takes four

clock cycles. During these four clock cycles, the Program Counter (2 bytes) is popped back from

the Stack, and the Stack Pointer is incremented by 2. When the AVR exits from an interrupt, it

will always return to the main program and execute one more instruction before any pending

interrupt is serviced.

4.17 Sleep Modes

To enter any of the three Sleep modes, the SE bit in MCUR must be set (one) and a SLEEP

instruction must be executed. The SM1 and SM0 bits in the MCUR register select which Sleep

mode (Idle, Power-down, or Power-save) will be activated by the SLEEP instruction, see Table

4-3 on page 54.

In Power-down and Power-save modes, the four external interrupts, EXT_INT0...3, and FPGA

interrupts, FPGA INT0...3, are triggered as low level-triggered interrupts. If an enabled interrupt

occurs while the MCU is in a Sleep mode, the MCU awakes, executes the interrupt routine, and

resumes execution from the instruction following SLEEP. The contents of the register file,

SRAM, and I/O memory are unaltered. If a reset occurs during Sleep mode, the MCU wakes up

and executes from the Reset vector

4.17.1

Idle Mode

When the SM1/SM0 bits are set to 00, the SLEEP instruction makes the MCU enter the Idle

mode, stopping the CPU but allowing UARTs, Timer/Counters, Watchdog 2-wire Serial and the

Interrupt System to continue operating. This enables the MCU to wake-up from external trig-

gered interrupts as well as internal ones like the Timer Overflow and UART Receive Complete

interrupts. When the MCU wakes up from Idle mode, the CPU starts program execution

immediately.

4.17.2

Power-down Mode

When the SM1/SM0 bits are set to 10, the SLEEP instruction makes the MCU enter the Power-

down mode. In this mode, the external oscillator is stopped, while the external interrupts and the

watchdog (if enabled) continue operating. Only an external reset, a watchdog reset (if enabled),

or an external level interrupt can wake-up the MCU.

In Power-down and Power-save modes, the four external interrupts, EXT_INT0...3, and FPGA

interrupts, FPGA_INT0...3, are treated as low-level triggered interrupts.

If a level-triggered interrupt is used for wake-up from Power-down mode, the changed level must

be held for some time to wake-up the MCU. This makes the MCU less sensitive to noise. The

changed level is sampled twice by the watchdog oscillator clock, and if the input has the required

level during this time, the MCU will wake-up. The period of the watchdog oscillator is 1 µs (nom-

inal) at 3.3V and 25°C. The frequency of the watchdog oscillator is voltage dependent.

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When waking up from Power-down mode, there is a delay from the wake-up condition occurs

until the wake-up becomes effective. This allows the clock to restart and become stable after

having been stopped. The wake-up period is defined by the same time-set bits that define the

reset time-out period. The wake-up period is equal to the clock reset period, as shown in

Figure 1 on page 93.

If the wake-up condition disappears before the MCU wakes up and starts to execute, the inter-

rupt causing the wake-up will not be executed.

4.17.3

Power-save Mode

When the SM1/SM0 bits are 11, the SLEEP instruction makes the MCU enter the Power-save

mode. This mode is identical to power-down, with one exception:

If Timer/Counter2 is clocked asynchronously, i.e., the AS2 bit in ASSR is set, Timer/Counter2

will run during sleep. In addition to the power-down wake-up sources, the device can also wake-

up from either Timer Overflow or Output Compare event from Timer/Counter2 if the correspond-

ing Timer/Counter2 interrupt enable bits are set in TIMSK. To ensure that the part executes the

Interrupt routine when waking up, also set the global interrupt enable bit in SREG.

When waking up from Power-save mode by an external interrupt, two instruction cycles are exe-

cuted before the interrupt flags are updated. When waking up by the asynchronous timer, three

instruction cycles are executed before the flags are updated. During these cycles, the processor

executes instructions, but the interrupt condition is not readable, and the interrupt routine has

not started yet. See Table 2-1 on page 15 for clock activity during Power-down, Power-save and

Idle modes.

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4.18 JTAG Interface and On-chip Debug System

4.18.1

Features

• JTAG (IEEE std. 1149.1 Compliant) Interface

• AVR I/O Boundary-scan Capabilities According to the JTAG Standard

• Debugger Access to:

– All Internal Peripheral Units

– AVR Program and Data SRAM

– The Internal Register File

– Program Counter/Instruction

– FPGA/AVR Interface

• Extensive On-chip Debug Support for Break Conditions, Including

– Break on Change of Program Memory Flow

– Single Step Break

– Program Memory Breakpoints on Single Address or Address Range

– Data Memory Breakpoints on Single Address or Address Range

– FPGA Hardware Break

– Frame Memory Breakpoint on Single Address

• On-chip Debugging Supported by AVR Studio version 4 or above

4.18.2

Overview

The AVR IEEE std. 1149.1 compliant JTAG interface is used for on-chip debugging.

The On-Chip Debug support is considered being private JTAG instructions, and distributed

within ATMEL and to selected third-party vendors only.

Figure 4-16 shows a block diagram of the JTAG interface and the On-Chip Debug system. The

TAP Controller is a state machine controlled by the TCK and TMS signals. The TAP Controller

selects either the JTAG Instruction Register or one of several Data Registers as the scan chain

(shift register) between the TDI - input and TDO - output. The Instruction Register holds JTAG

instructions controlling the behavior of a Data Register.

Of the Data Registers, the ID-Register, Bypass Register, and the AVR I/O Boundary-Scan Chain

are used for board-level testing. The Internal Scan Chain and Break-Point Scan Chain are used

for On-Chip debugging only.

4.18.3

The Test Access Port – TAP

The JTAG interface is accessed through four of the AVR’s pins. In JTAG terminology, these pins

constitute the Test Access Port - TAP. These pins are:

• TMS: Test Mode Select. This pin is used for navigating through the TAP-controller state

machine.

• TCK: Test Clock. JTAG operation is synchronous to TCK

• TDI: Test Data In. Serial input data to be shifted in to the Instruction Register or Data Register

(Scan Chains)

• TDO: Test Data Out. Serial output data from Instruction register or Data Register

The IEEE std. 1149.1 also specifies an optional TAP signal; TRST - Test ReSeT - which is not

provided.

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When the JTAGEN bit is unprogrammed, these four TAP pins revert to normal operation. When

programmed, the input TAP signals are internally pulled High and the JTAG is enabled for

Boundary-Scan. System Designer sets this bit by default.

For the On-Chip Debug system, in addition the RESET pin is monitored by the debugger to be

able to detect external reset sources. The debugger can also pull the RESET pin Low to reset

the whole system, assuming only open collectors on reset line are used in the application.

Figure 4-16. Block Diagram

PORT E

DEVICE BOUNDARY

AVR BOUNDARY-SCAN CHAIN

FPGA-AVR

SCAN CHAIN

TDI

FPGA-SRAM

SCAN CHAIN

TDO

TCK

TMS

TAP

CONTROLLER

AVR CPU

INTERNAL

SCAN

CHAIN

PROGRAM/DATA

SRAM

PC

JTAG INSTRUCTION

Instruction

REGISTER

DEVICE ID

REGISTER

BREAKPOINT

UNIT

M

U

X

FLOW CONTROL

UNIT

BYPASS

REGISTER

DIGITAL

PERIPHERAL

UNITS

M

U

X

BREAKPOINT

SCAN CHAIN

OCD / AVR CORE

COMMUNICATION

INTERFACE

ADDRESS

DECODER

OCD STATUS

AND CONTROL

AVR RESET

SCAN CHAIN

RESET CONTROL

UNIT

2-wire Serial

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Figure 4-17. TAP Controller State Diagram

1

Test-Logic-Reset

0

1

0

Run-Test/Idle

Select-DR Scan

Select-IR Scan

0

1

Capture-DR

Capture-IR

0

Shift-IR

1

Shift-DR

0

1

Exit1-DR

0

1

Exit1-IR

0

Pause-DR

1

0

Pause-IR

1

0

Exit2-DR

1

Exit2-IR

1

Update-DR

Update-IR

1

0

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4.18.3.1

TAP Controller

The TAP controller is a 16-state finite state machine that controls the operation of the Boundary-

Scan circuitry and On-Chip Debug system. The state transitions depicted in Figure 4-17 depend

on the signal present on TMS (shown adjacent to each state transition) at the time of the rising

edge at TCK. The initial state after a Power-On Reset is Test-Logic-Reset.

As a definition in this document, the LSB is shifted in and out first for all shift registers.

Assuming Run-Test/Idle is the present state, a typical scenario for using the JTAG interface is

• At the TMS input, apply the sequence 1, 1, 0, 0 at the rising edges of TCK to enter the Shift

Instruction Register - Shift-IR state. While TMS is Low, shift the 4 bit JTAG instructions into

the JTAG instruction register from the TDI input at the rising edge of TCK, while the captured

IR-state 0x01 is shifts out on the TDO pin. The JTAG Instruction selects a particular Data

Register as path between TDI and TDO and controls the circuitry surrounding the selected

Data Register.

• Apply the TMS sequence 1, 1, 0 to re-enter the Run-Test/Idle state. The instruction is latched

onto the parallel output from the shift register path in the Update-IR state. The Exit-IR, Pause-

IR, and Exit2-IR states are only used for navigating the state machine.

• At the TMS input, apply the sequence 1, 0, 0 at the rising edges of TCK to enter the Shift

Data Register - Shift-DR state. While TMS is Low, upload the selected Data Register

(selected by the present JTAG instruction in the JTAG Instruction Register) from the TDI input

at the rising edge of TCK. At the same time, the parallel inputs to the Data Register captured

in the Capture-DR state shifts out on the TDO pin.

• Apply the TMS sequence 1, 1, 0 to re-enter the Run-Test/Idle state. If the selected Data

Register has a latched parallel-output, the latching takes place in the Update-DR state. The

Exit-DR, Pause-DR, and Exit2-DR states are only used for navigating the state machine.

As shown in Figure 4-17 on page 73, the Run-Test/Idle⁽¹⁾state need not be entered between

selecting JTAG instruction and using Data Registers, and some JTAG instructions may select

certain functions to be performed in the Run-Test/Idle, making it unsuitable as an Idle state.

Note:

1. Independent of the initial state of the TAP Controller, the Test-Logic-Reset state can always be

entered by holding TMS High for 5 TCK clock periods.

4.18.4

4.18.5

Using the Boundary-scan Chain

A complete description of the Boundary-Scan capabilities are given in the section “IEEE 1149.1

(JTAG) Boundary-scan” on page 76.

Using the On-chip Debug System

As shown in Figure 4-16, the hardware support for On-Chip Debugging consists mainly of

• A scan chain on the interface between the internal AVR CPU and the internal peripheral units

• A breakpoint unit

• A communication interface between the CPU and JTAG system

• A scan chain on the interface between the internal AVR CPU and the FPGA

• A scan chain on the interface between the internal Program/Data SRAM and the FPGA

All read or modify/write operations needed for implementing the Debugger are done by applying

AVR instructions via the internal AVR CPU Scan Chain. The CPU sends the result to an I/O

memory mapped location which is part of the communication interface between the CPU and the

JTAG system.

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The Breakpoint Unit implements Break on Change of Program Flow, Single Step Break, 2 Pro-

gram Memory Breakpoints, and 2 combined break points. Together, the 4 break-points can be

configured as either:

• 4 single Program Memory break points

• 3 Single Program Memory break point + 1 single Data Memory break point

• 2 single Program Memory break points + 2 single Data Memory break points

• 2 single Program Memory break points + 1 Program Memory break point with mask (‘range

break point’)

• 2 single Program Memory break points + 1 Data Memory break point with mask (‘range break

point’)

• 1 single Frame Memory break point is available parallel to all the above combinations

A list of the On-Chip Debug specific JTAG instructions is given in “On-chip Debug Specific JTAG

Instructions”. Atmel supports the On-Chip Debug system with the AVR Studio front-end software

for PCs. The details on hardware implementation and JTAG instructions are therefore irrelevant

for the user of the On-Chip Debug system.

The JTAG Enable bit must be set (one) in the System Control Register to enable the JTAG Test

Access Port. In addition, the On-chip Debug Enable bit must be set (one).

The AVR Studio enables the user to fully control execution of programs on an AVR device with

On-Chip Debug capability, AVR In-Circuit Emulator, or the built-in AVR Instruction Set Simula-

tor. AVR Studio supports source level execution of Assembly programs assembled with Atmel

Corporation’s AVR Assembler and C programs compiled with third-party vendors’ compilers.

AVR Studio runs under Microsoft^®Windows^®95/98/2000 and Microsoft WindowsNT^®.

All necessary execution commands are available in AVR Studio, both on source level and on

disassembly level. The user can execute the program, single step through the code either by

tracing into or stepping over functions, step out of functions, place the cursor on a statement and

execute until the statement is reached, stop the execution, and reset the execution target. In

addition, the user can have up to 2 data memory breakpoints, alternatively combined as a mask

(range) break-point.

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4.18.6

On-chip Debug Specific JTAG Instructions

The On-Chip debug support is considered being private JTAG instructions, and distributed

within ATMEL and to selected third-party vendors only. Table 4-8 lists the instruction opcode.

Table 4-8.

JTAG Instruction and Code

JTAG Instruction

EXTEST

4-bit Code

$0 (0000)

Selected Scan Chain

AVR I/O Boundary

Device ID

# Bits

69

IDCODE

$1 (0001)

$2 (0010)

$3 (0011)

$4 (0100)

$5 (0101)

$6 (0110)

$7 (0111)

$8 (1000)

$9 (1001)

$A (1010)

$B (1011)

$C (1100)

$D (1101)

$E (1110)

$F (1111)

32

69

–

SAMPLE_PRELOAD

RESERVED

PRIVATE

AVR I/O Boundary

N/A

FPSLIC On-chip Debug System

N/A

–

PRIVATE

–

PRIVATE

–

RESERVED

PRIVATE

–

FPSLIC On-chip Debug System

AVR Reset

–

PRIVATE

–

PRIVATE

–

PRIVATE

–

AVR_RESET

RESERVED

BYPASS

1

N/A

–

N/A

–

Bypass

1

4.19 IEEE 1149.1 (JTAG) Boundary-scan

4.19.1

Features

• JTAG (IEEE std. 1149.1 compliant) Interface

• Boundary-scan Capabilities According to the JTAG Standard

• Full Scan of All Port Functions

• Supports the Optional IDCODE Instruction

• Additional Public AVR_RESET Instruction to Reset the AVR

4.19.2

System Overview

The Boundary-Scan chain has the capability of driving and observing the logic levels on the

AVR’s digital I/O pins. At system level, all ICs having JTAG capabilities are connected serially by

the TDI/TDO signals to form a long shift register. An external controller sets up the devices to

drive values at their output pins, and observe the input values received from other devices. The

controller compares the received data with the expected result. In this way, Boundary-Scan pro-

vides a mechanism for testing interconnections and integrity of components on Printed Circuits

Boards by using the 4 TAP signals only.

The four IEEE 1149.1 defined mandatory JTAG instructions IDCODE, BYPASS, SAMPLE/PRE-

LOAD, and EXTEST, as well as the AVR specific public JTAG instruction AVR_RESET can be

used for testing the Printed Circuit Board. Initial scanning of the data register path will show the

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ID-code of the device, since IDCODE is the default JTAG instruction. It may be desirable to have

the AVR device in reset during test mode. If not reset, inputs to the device may be determined by

the scan operations, and the internal software may be in an undetermined state when exiting the

test mode. If needed, the BYPASS instruction can be issued to make the shortest possible scan

chain through the device. The AVR can be set in the reset state either by pulling the external

AVR RESET pin Low, or issuing the AVR_RESET instruction with appropriate setting of the

Reset Data Register.

The EXTEST instruction is used for sampling external pins and loading output pins with data.

The data from the output latch will be driven out on the pins as soon as the EXTEST instruction

is loaded into the JTAG IR-register. Therefore, the SAMPLE/PRELOAD should also be used for

setting initial values to the scan ring, to avoid damaging the board when issuing the EXTEST

instruction for the first time. SAMPLE/PRELOAD can also be used for taking a snapshot of the

AVR’s external pins during normal operation of the part.

The JTAG Enable bit must be programmed and the JTD bit in the I/O register MCUR must be

cleared to enable the JTAG Test Access Port.

When using the JTAG interface for Boundary-Scan, using a JTAG TCK clock frequency higher

than the internal chip frequency is possible. The chip clock is not required to run.

4.19.3

Data Registers

The Data Registers are selected by the JTAG instruction registers described in section “Bound-

ary-scan Specific JTAG Instructions” on page 79. The data registers relevant for Boundary-Scan

operations are:

• Bypass Register

• Device Identification Register

• AVR Reset Register

• AVR Boundary-Scan Chain

4.20 Bypass Register

The Bypass register consists of a single shift-register stage. When the Bypass register is

selected as path between TDI and TDO, the register is reset to 0 when leaving the Capture-DR

controller state. The Bypass register can be used to shorten the scan chain on a system when

the other devices are to be tested.

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4.21 Device Identification Register

Figure 4-18 shows the structure of the Device Identification register.

Figure 4-18. The format of the Device Identification Register

MSB

LSB

0

Bit

31

28

27

12

11

1

Device ID

Version

4 bits

Part Number

16 bits

Manufacturer ID

1

11 bits

1 bit

Version

Version is a 4-bit number identifying the revision of the component. The relevant version num-

bers are shown in Table 4-9.

Table 4-9.

Device

JTAG Part Version

Version (Binary Digits)

AT94K05

AT94K10

AT94K40

–

0010

–

Part Number

The part number is a 16 bit code identifying the component. The JTAG Part Number for AVR

devices is listed in Table 4-10.

Table 4-10. JTAG Part Number

Device

Part Number (Hex)

0xdd77

AT94K05

AT94K10

AT94K40

0xdd73

0xdd76

Manufacturer ID

The manufacturer ID for ATMEL is 0x01F (11 bits).

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4.22 AVR Reset Register

The AVR Reset Register is a Test Data Register used to reset the AVR. A high value in the

Reset Register corresponds to pulling the external AVRResetn Low. The AVR is reset as long as

there is a high value present in the AVR Reset Register. Depending on the Bit settings for the

clock options, the CPU will remain reset for a Reset Time-Out Period after releasing the AVR

Reset Register. The output from this Data Register is not latched, so the reset will take place

immediately, see Figure 4-19.

Figure 4-19. Reset Register

To

TDO

From other internal and

external reset sources

From

TDI

Internal AVR Reset

D

Q

ClockDR · AVR_RESET

4.22.1

4.22.2

Boundary-scan Chain

The Boundary-scan Chain has the capability of driving and observing the logic levels on the

AVR’s digital I/O pins.

See “Boundary-scan Chain” on page 80 for a complete description.

Boundary-scan Specific JTAG Instructions

The instruction register is 4-bit wide, supporting up to 16 instructions. Listed below are the JTAG

instructions useful for Boundary-Scan operation. Note that the optional HIGHZ instruction is not

implemented.

As a definition in this data sheet, the LSB is shifted in and out first for all shift registers.

The OPCODE for each instruction is shown behind the instruction name in hex format. The text

describes which data register is selected as path between TDI and TDO for each instruction.

4.22.2.1

EXTEST; $0

Mandatory JTAG instruction for selecting the Boundary-Scan Chain as Data Register for testing

circuitry external to the AVR package. For port-pins, Pull-up Disable, Output Control, Output

Data, and Input Data are all accessible in the scan chain. For Analog circuits having off-chip

connections, the interface between the analog and the digital logic is in the scan chain. The con-

tents of the latched outputs of the Boundary-Scan chain are driven out as soon as the JTAG IR-

register is loaded by the EXTEST instruction.

The active states are:

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• Capture-DR: Data on the external pins are sampled into the Boundary-Scan Chain.

• Shift-DR: The Internal Scan Chain is shifted by the TCK input.

• Update-DR: Data from the scan chain is applied to output pins.

4.22.2.2

IDCODE; $1

Optional JTAG instruction selecting the 32-bit ID register as Data Register. The ID register con-

sists of a version number, a device number and the manufacturer code chosen by JEDEC. This

is the default instruction after power-up.

The active states are:

• Capture-DR: Data in the IDCODE register is sampled into the Boundary-Scan Chain.

• Shift-DR: The IDCODE scan chain is shifted by the TCK input.

4.22.2.3

SAMPLE_PRELOAD; $2

Mandatory JTAG instruction for pre-loading the output latches and taking a snap-shot of the

input/output pins without affecting the system operation. However, the output latches are not

connected to the pins. The Boundary-Scan Chain is selected as Data Register.

The active states are:

• Capture-DR: Data on the external pins are sampled into the Boundary-Scan Chain.

• Shift-DR: The Boundary-Scan Chain is shifted by the TCK input.

• Update-DR: Data from the Boundary-Scan chain is applied to the output latches. However,

the output latches are not connected to the pins.

4.22.2.4

AVR_RESET; $C

The AVR specific public JTAG instruction for forcing the AVR device into the Reset Mode or

releasing the JTAG reset source. The TAP controller is not reset by this instruction. The one bit

Reset Register is selected as Data Register. Note that the reset will be active as long as there is

a logic “1” in the Reset Chain. The output from this chain is not latched.

The active state is:

• Shift-DR: The Reset Register is shifted by the TCK input.

4.22.2.5

BYPASS; $F

Mandatory JTAG instruction selecting the Bypass Register for Data Register.

The active states are:

• Capture-DR: Loads a logic “0” into the Bypass Register.

• Shift-DR: The Bypass Register cell between TDI and TDO is shifted.

4.22.3

Boundary-scan Chain

The Boundary-Scan chain has the capability of driving and observing the logic levels on the

AVR’s digital I/O pins.

4.22.3.1

Scanning the Digital Port Pins

Figure 4-20 shows the boundary-scan cell for bi-directional port pins with pull-up function. The

cell consists of a standard boundary-scan cell for the pull-up function, and a bi-directional pin

cell that combines the three signals Output Control (OC), Output Data (OD), and Input Data (ID),

into only a two-stage shift register.

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AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-20. Boundary-scan Cell For Bi-directional Port Pin with Pull-up Function

ShiftDR

To Next Cell

EXTEST

Vcc

Pullup Disable (PLD)

0

1

FF2

Q

LD2

0

1

D

Q

G

Output Control (OC)

FF1

D Q

LD1

0

1

0

1

D

G

Q

Output Data (OD)

0

1

FF0

D

LD0

0

1

0

1

Q

D

G

Q

Input Data (ID)

From Last Cell

ClockDR

UpdateDR

81

1138H–FPSLI–6/05

Figure 4-21 shows a simple digital Port Pin as described in the section “I/O Ports” on page 158.

The Boundary-Scan details from Figure 4-20 replaces the dashed box in Figure 4-21.

Figure 4-21. General Port Pin Schematic Diagram

RD

PLD

PULL-UP

PUD

RESET

Q

D

DDXn

C

WD

OC

RESET

OD

Q

D

PXn

PORTXn

C

ID

RL

WP

RP

WP: WRITE PORTX

WD: WRITE DDRX

RL: READ PORTX LATCH

RP: READ PORTX PIN

RD: READ DDRX

n:

0-7

PUD: PULL-UP DISABLE

PuD: JTAG PULL-UP DISABLE

OC: JTAG OUTPUT CONTROL

OD: JTAG OUTPUT DATA

ID: JTAG INPUT DATA

82

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

When no alternate port function is present, the Input Data - ID corresponds to the PINn register

value, Output Data corresponds to the PORTn register, Output Control corresponds to the Data

Direction (DDn) register, and the PuLL-up Disable (PLD) corresponds to logic expression (DDn

OR NOT(PORTBn)).

Digital alternate port functions are connected outside the dashed box in Figure 4-21 to make the

scan chain read the actual pin value.

4.22.3.2

Scanning AVR RESET

Multiple sources contribute to the internal AVR reset; therefore, the AVR reset pin is not

observed. Instead, the internal AVR reset signal output from the Reset Control Unit is observed,

see Figure 4-22. The scanned signal is active High if AVRResetn is Low and enabled or the

device is in general reset (Resetn or power-on) or configuration download.

Figure 4-22. Observe-only Cell

To

Cell

RESET CONTROL

UNIT

To System Logic

FF1

0

1

D

Q

From

ClockDR

83

1138H–FPSLI–6/05

4.22.3.3

Scanning 2-wire Serial

The SCL and SDA pins are open drain, bi-directional and enabled separately. The “Enable Out-

put” bits (active High) in the scan chain are supported by general boundary-scan cells. Enabling

the output will drive the pin Low from a tri-state. External pull-ups on the 2-wire bus are required

to pull the pins High if the output is disabled. The “Data Out/In” and “Clock Out/In” bits in the

scan chain are observe-only cells. Figure 4-23 shows how each pin is connected in the scan

chain.

Figure 4-23. Boundary-scan Cells for 2-wire Serial

From Previous Cell

To 2-wire

Serial Logic

Data or Clock Out/In

(Observe Only Cell)

SDA or

SCL

From 2-wire

Serial Logic

Enable Output

(General Boundary

Scan Cell)

To Next Cell

4.22.3.4

Scanning the Clock Pins

Figure 4-24 shows how each oscillator with external connection is supported in the scan chain.

The Enable signal is supported with a general boundary-scan cell, while the oscillator/clock out-

put is attached to an observe-only cell. In addition to the main clock, the timer oscillator is

scanned in the same way. The output from the internal RC-Oscillator is not scanned, as this

oscillator does not have external connections.

Figure 4-24. Boundary-scan Cells for Oscillators and Clock Options

XTAL1/TOSC1 XTAL2/TOSC2

To

ShiftDR

EXTEST

Oscillator

ShiftDR

From digital logic

0

1

To system logic

OUTPUT

ENABLE

FF1

D Q

0

1

D Q

G

0

1

UpdateDR

ClockDR

From

previous cell

ClockDR

From

previous cell

84

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Scanning an oscillator output gives unpredictable results as there is a frequency drift between

the internal oscillator and the JTAG TCK clock.

The clock configuration is programmed in the SCR. As an SCR bit is not changed run-time, the

clock configuration is considered fixed for a given application. The user is advised to scan the

same clock option as to be used in the final system. The enable signals are supported in the

scan chain because the system logic can disable clock options in sleep modes, thereby discon-

necting the oscillator pins from the scan path if not provided.

The XTAL or TOSC “Clock In” Scan chain bit will always capture “1” if the oscillator is disabled

(“Enable Clock” bit is active Low).

4.22.4

FPSLIC Boundary-scan Order

Table 4-11 shows the Scan order between TDI and TDO when the Boundary-Scan chain is

selected as data path. Bit 0 is the LSB; the first bit scanned in, and the first bit scanned out. In

Figure 4-20, “Data Out/In – PXn” corresponds to FF0, “Enable Output – PXn” corresponds to

FF1, and “Pull-up – PXn” corresponds to FF2.

Table 4-11. AVR I/O Boundary Scan – JTAG Instructions $0/$2

I/O Ports

Description

Data Out/In - PE7

Enable Output - PE7

Pull-up - PE7

Bit

68

67

66

65

64

63

62

61

60

59

58

57

56

55

54

53

52

51

50

49

48

47

46

45

<- TDI

Data Out/In - PE6

Enable Output - PE6

Pull-up - PE6

Data Out/In - PE5

Enable Output - PE5

Pull-up - PE5

Data Out/In - PE4

Enable Output - PE4

Pull-up - PE4

PORTE

Data Out/In - PE3

Enable Output - PE3

Pull-up - PE3

Data Out/In - PE2

Enable Output - PE2

Pull-up - PE2

Data Out/In - PE1

Enable Output - PE1

Pull-up - PE1

Data Out/In - PE0

Enable Output - PE0

Pull-up - PE0

85

1138H–FPSLI–6/05

Table 4-11. AVR I/O Boundary Scan – JTAG Instructions $0/$2 (Continued)

I/O Ports

Description

Data Out/In - PD7

Enable Output - PD7

Pull-up - PD7

Bit

44

43

42

Data Out/In - PD6

Enable Output - PD6

Pull-up - PD6

41

40

39

Data Out/In - PD5

Enable Output - PD5

Pull-up - PD5

38

37

36

Data Out/In - PD4

Enable Output - PD4

Pull-up - PD4

35

34

33

PORTD

Data Out/In - PD3

Enable Output - PD3

Pull-up - PD3

32

31

30

Data Out/In - PD2

Enable Output - PD2

Pull-up - PD2

29

28

27

Data Out/In - PD1

Enable Output - PD1

Pull-up - PD1

26

25

24

Data Out/In - PD0

Enable Output - PD0

Pull-up - PD0

23

22

21

Input with Pull-up - INTP3

Input with Pull-up - INTP2

Input with Pull-up - INTP1

Input with Pull-up - INTP0

Data Out/In - TX1

Enable Output - TX1

Pull-up - TX1

20⁽¹⁾

19⁽¹⁾

18⁽¹⁾

17⁽¹⁾

16

EXT. INTERRUPTS

15

UART1

14

Input with Pull-up - RX1

Data Out/In - TX0

Enable Output - TX0

Pull-up - TX0

13⁽¹⁾

12

11

UART0

XTAL

10

Input with Pull-up - RX0

Clock In - XTAL1

9⁽¹⁾

8⁽¹⁾

7

Enable Clock - XTAL 1

86

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 4-11. AVR I/O Boundary Scan – JTAG Instructions $0/$2 (Continued)

I/O Ports

Description

Clock In - TOSC 1

Enable Clock - TOSC 1

Data Out/In - SDA

Enable Output - SDA

Clock Out/In - SCL

Enable Output - SCL

AVR Reset

Bit

6⁽¹⁾

5

TOSC

4⁽¹⁾

3

2-wire Serial

2⁽¹⁾

1

(2)

0⁽¹⁾

-> TDO

Notes: 1. Observe-only scan cell.

2. AVR Reset is High (one) if AVRResetn activated (Low) and enabled or the device is in

general reset (Resetn or power-on) or configuration download.

Table 4-12. Bit EXTEST and SAMPLE_PRELOAD

Bit Type EXTEST

SAMPLE_PRELOAD

Capture-DR grabs signal from

pad if output disabled, or from the

AVR if the output drive is enabled.

Defines value driven if enabled.

Capture-DR grabs signal on pad.

Data Out/In - PXn

1 = output drive enabled.

Enable Output - PXn Capture-DR grabs output enable

scan latch.

Capture-DR grabs output enable

from the AVR.

1 = pull-up disabled.

Pull-up - PXn Capture-DR grabs pull-up control

from the AVR.

Capture-DR grabs pull-up control

from the AVR.

Observe only. Capture-DR grabs

Input with Pull-up - INTPn

Capture-DR grabs signal from

pad.

signal from pad.

Capture-DR always grabs “0”

since Tx input is NC and tied to

ground internally.

Defines value driven if enabled.

Data Out - TXn

Capture-DR grabs signal on pad.

1 = output drive enabled.

Enable Output - TXn Capture-DR grabs output enable

scan latch.

Capture-DR grabs output enable

from the AVR.

1 = pull-up disabled.

Pull-up - TXn Capture-DR grabs pull-up control

from the AVR.

Capture-DR grabs pull-up control

from the AVR.

Observe only. Capture-DR grabs

Input with Pull-up - RXn

Capture-DR grabs signal from

pad.

signal from pad.

Capture-DR grabs signal from

pad if clock is enabled, “1” if

disabled.

Observe only. Capture-DR grabs

Clock In - XTAL1

signal from pad.

1 = clock disabled. Capture-DR

Enable Clock - XTAL 1

Capture-DR grabs enable from

the AVR.

grabs clock enable from the AVR.

Capture-DR grabs signal from

pad if clock is enabled, “1” if

disabled.

Observe only. Capture-DR grabs

Clock In - TOSC 1

signal from pad.

87

1138H–FPSLI–6/05

Table 4-12. Bit EXTEST and SAMPLE_PRELOAD (Continued)

Bit Type EXTEST SAMPLE_PRELOAD

1 = clock disabled. Capture-DR

Capture-DR grabs enable from

the AVR.

Enable Clock - TOSC 1

grabs clock enable from the AVR.

Observe only. Capture-DR grabs

signal from pad.

Capture-DR grabs signal from

pad.

Data Out/In - SDA

1 = drive “0”

0 = drive disabled, bus pull-up

Capture-DR grabs output enable

scan latch.

Capture-DR grabs output enable

from the AVR.

Enable Output - SDA

Clock Out/In - SCL

Enable Output - SCL

Observe only. Capture-DR grabs

signal from pad.

Capture-DR grabs signal from

pad.

1 = drive “0”

0 = drive disabled, bus pull-up

Capture-DR grabs output enable

scan latch.

Capture-DR grabs output enable

from the AVR.

Internal, observe only.

AVR Reset Capture-DR grabs internal AVR

reset signal.

Capture-DR grabs internal AVR

reset signal.

4.22.5

Boundary-scan Description Language Files

Boundary-Scan Description Language (BSDL) files describe Boundary-Scan capable devices in

a standard format used by automated test-generation software. The order and function of bits in

the Boundary-Scan data register are included in this description. A BSDL file for AT94K Family

is available.

88

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.23 Timer/Counters

The FPSLIC provides three general-purpose Timer/Counters: two 8-bit T/Cs and one 16-bit T/C.

Timer/Counter2 can optionally be asynchronously clocked from an external oscillator. This oscil-

lator is optimized for use with a 32.768 kHz watch crystal, enabling use of Timer/Counter2 as a

Real-time Clock (RTC). Timer/Counters 0 and 1 have individual prescaling selection from the

same 10-bit prescaling timer. Timer/Counter2 has its own prescaler. Both these prescalers can

be reset by setting the corresponding control bits in the Special Functions I/O Register (SFIOR).

See “Special Function I/O Register – SFIOR” on page 90 for a detailed description. These

Timer/Counters can either be used as a timer with an internal clock time-base or as a counter

with an external pin connection which triggers the counting.

4.24 Timer/Counter Prescalers

For Timer/Counters 0 and 1, see Figure 4-25, the four prescaled selections are: CK/8, CK/64,

CK/256 and CK/1024, where CK is the oscillator clock. For the two Timer/Counters 0 and 1, CK,

external source, and stop, can also be selected as clock sources. Setting the PSR10 bit in

SFIOR resets the prescaler. This allows the user to operate with a predictable prescaler. Note

that Timer/Counter1 and Timer/Counter0 share the same prescaler and a prescaler reset will

affect both Timer/Counters.

Figure 4-25. Prescaler for Timer/Counter0 and 1

Clear

PSR10

TCK1

TCK0

The clock source for Timer/Counter2 prescaler, see Figure 4-26, is named PCK2. PCK2 is by

default connected to the main system clock CK. By setting the AS2 bit in ASSR, Timer/Counter2

is asynchronously clocked from the TOSC1 pin. This enables use of Timer/Counter2 as a Real-

time Clock (RTC). When AS2 is set, pins TOSC1 and TOSC2 are disconnected from Port D. A

crystal can then be connected between the TOSC1 and TOSC2 pins to serve as an independent

clock source for Timer/Counter2. The oscillator is optimized for use with a 32.768 kHz crystal.

Alternatively, an external clock signal can be applied to TOSC1. The frequency of this clock

must be lower than one fourth of the CPU clock and not higher than 1 MHz. Setting the PSR2 bit

in SFIOR resets the prescaler. This allows the user to operate with a predictable prescaler.

89

1138H–FPSLI–6/05

Figure 4-26. Timer/Counter2 Prescaler

CK

PCK2

10-BIT T/C PRESCALER

Clear

TOSC1

AS2

PSR2

0

CS20

CS21

CS22

TIMER/COUNTER2 CLOCK SOURCE

TCK2

Special Function I/O Register – SFIOR

Bit

7

-

6

-

5

-

4

-

3

-

2

-

1

0

$30 ($50)

Read/Write

Initial Value

PSR2

R/W

0

PSR10

R/W

0

SFIOR

R

0

R

0

R

0

R

0

R

0

R

0

• Bits 7..2 - Res: Reserved Bits

These bits are reserved bits in the FPSLIC and are always read as zero.

• Bit 1 - PSR2: Prescaler Reset Timer/Counter2

When this bit is set (one) the Timer/Counter2 prescaler will be reset. The bit will be cleared by

the hardware after the operation is performed. Writing a zero to this bit will have no effect. This

bit will always be read as zero if Timer/Counter2 is clocked by the internal CPU clock. If this bit is

written when Timer/Counter2 is operating in asynchronous mode; however, the bit will remain as

one until the prescaler has been reset. See “Asynchronous Operation of Timer/Counter2” on

page 99 for a detailed description of asynchronous operation.

• Bit 0 - PSR10: Prescaler Reset Timer/Counter1 and Timer/Counter0

When this bit is set (one) the Timer/Counter1 and Timer/Counter0 prescaler will be reset. The bit

will be cleared by the hardware after the operation is performed. Writing a zero to this bit will

have no effect. Note that Timer/Counter1 and Timer/Counter0 share the same prescaler and a

reset of this prescaler will affect both timers. This bit will always be read as zero.

4.25 8-bit Timers/Counters T/C0 and T/C2

Figure 4-27 shows the block diagram for Timer/Counter0. Figure 4-28 shows the block diagram

for Timer/Counter2.

90

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-27. Timer/Counter0 Block Diagram

T/C0 OVER- T/C0 COMPARE

FLOW IRQ MATCH IRQ

TIMER INT. MASK

REGISTER (TIMSK)

TIMER INT. FLAG

REGISTER (TIFR)

T/C0 CONTROL

REGISTER (TCCR0)

SPECIAL FUNCTIONS

IO REGISTER (SFIOR)

7

0

T/C CLEAR

TIMER/COUNTER0

(TCNT0)

T/C CLK SOURCE

UP/DOWN

CK

CONTROL

LOGIC

T0

8-BIT COMPARATOR

OUTPUT COMPARE

REGISTER0 (OCR0)

Figure 4-28. Timer/Counter2 Block Diagram

T/C2 OVER- T/C2 COMPARE

FLOW IRQ MATCH IRQ

8-BIT DATA BUS

8-BIT ASYNCH T/C2 DATA BUS

SPECIAL FUNCTIONS

IO REGISTER (SFIOR)

T/C2 CONTROL

REGISTER (TCCR2)

TIMER INT. MASK

REGISTER (TIMSK)

TIMER INT. FLAG

REGISTER (TIFR)

7

0

T/C CLEAR

TIMER/COUNTER2

(TCNT2)

T/C CLK SOURCE

UP/DOWN

CK

CONTROL

LOGIC

TOSC1

8-BIT COMPARATOR

OUTPUT COMPARE

REGISTER2 (OCR2)

ASYNCH. STATUS

REGISTER (ASSR)

CK

TCK2

SYNCH UNIT

91

1138H–FPSLI–6/05

The 8-bit Timer/Counter0 can select the clock source from CK, prescaled CK, or an external pin.

The 8-bit Timer/Counter2 can select the clock source from CK, prescaled CK or external

TOSC1.

Both Timers/Counters can be stopped as described in section “Timer/Counter0 Control Register

– TCCR0” on page 92 and “Timer/Counter2 Control Register – TCCR2” on page 92.

The various status flags (overflow and compare match) are found in the Timer/Counter Interrupt

Flag Register (TIFR). Control signals are found in the Timer/Counter Control Register (TCCR0

and TCCR2). The interrupt enable/disable settings are found in the Timer/Counter Interrupt

Mask Register – TIMSK.

When Timer/Counter0 is externally clocked, the external signal is synchronized with the oscilla-

tor frequency of the CPU. To assure proper sampling of the external clock, the minimum time

between two external clock transitions must be at least one internal CPU clock period. The

external clock signal is sampled on the rising edge of the internal CPU clock.

The 8-bit Timer/Counters feature both a high-resolution and a high-accuracy usage with the

lower prescaling opportunities. Similarly, the high prescaling opportunities make the

Timer/Counter0 useful for lower speed functions or exact-timing functions with infrequent

actions.

Timer/Counters 0 and 2 can also be used as 8-bit Pulse Width Modulators (PWM). In this mode,

the Timer/Counter and the output compare register serve as a glitch-free, stand-alone PWM with

centered pulses. See “Timer/Counter 0 and 2 in PWM Mode” on page 95 for a detailed descrip-

tion on this function.

Timer/Counter0 Control Register – TCCR0

Bit

7

6

5

4

3

2

1

0

$33 ($53)

Read/Write

Initial Value

FOC0

R/W

0

PWM0

R/W

0

COM01

R/W

0

COM00

R/W

0

CTC0

R/W

0

CS02

R/W

0

CS01

R/W

0

CS00

R/W

0

TCCR0

Timer/Counter2 Control Register – TCCR2

Bit

7

6

5

4

3

2

1

0

$27 ($47)

Read/Write

Initial Value

FOC2

R/W

0

PWM2

R/W

0

COM21

R/W

0

COM20

R/W

0

CTC2

R/W

0

CS22

R/W

0

CS21

R/W

0

CS20

R/W

0

TCCR2

• Bit 7 - FOC0/FOC2: Force Output Compare

Writing a logic 1 to this bit forces a change in the compare match output pin PE1

(Timer/Counter0) and PE3 (Timer/Counter2) according to the values already set in COMn1 and

COMn0. If the COMn1 and COMn0 bits are written in the same cycle as FOC0/FOC2, the new

settings will not take effect until next compare match or Forced Output Compare match occurs.

The Force Output Compare bit can be used to change the output pin without waiting for a com-

pare match in the timer. The automatic action programmed in COMn1 and COMn0 happens as if

a Compare Match had occurred, but no interrupt is generated and the Timer/Counters will not be

cleared even if CTC0/CTC2 is set. The FOC0/FOC2 bits will always be read as zero. The setting

of the FOC0/FOC2 bits has no effect in PWM mode.

92

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

• Bit 6 - PWM0/PWM2: Pulse Width Modulator Enable

When set (one) this bit enables PWM mode for Timer/Counter0 or Timer/Counter2. This mode is

described on page 95.

• Bits 5,4 - COM01, COM00/COM21, COM20: Compare Output Mode, Bits 1 and 0

The COMn1 and COMn0 control bits determine any output pin action following a compare match

in Timer/Counter0 or Timer/Counter2. Output pin actions affect pins PE1(OC0) or PE3(OC2).

This is an alternative function to an I/O port, and the corresponding direction control bit must be

set (one) to control an output pin. The control configuration is shown in Table 1.

Table 1. Compare Output Mode Select⁽¹⁾

COMn1

COMn0

Description

0

1

0

1

0

1

Timer/Counter disconnected from output pin OCn⁽²⁾

Toggles the OCn⁽²⁾output line.

Clears the OCn⁽²⁾output line (to zero).

Sets the OCn⁽²⁾output line (to one).

Notes: 1. In PWM mode, these bits have a different function. Refer to Table 4-15 for a detailed

description.

2. n = 0 or 2

• Bit 3 - CTC0/CTC2: Clear Timer/Counter on Compare Match

When the CTC0 or CTC2 control bit is set (one), Timer/Counter0 or Timer/Counter2 is reset to

$00 in the CPU clock-cycle after a compare match. If the control bit is cleared, Timer/Counter

continues counting and is unaffected by a compare match. When a prescaling of 1 is used, and

the compare register is set to C, the timer will count as follows if CTC0/CTC2 is set:

... | C-1 | C | 0 | 1 | ...

When the prescaler is set to divide by 8, the timer will count like this:

... | C-1, C-1, C-1, C-1, C-1, C-1, C-1, C-1 | C, C, C, C, C, C, C, C | 0, 0, 0, 0, 0, 0, 0, 0 | 1, 1, 1, ...

In PWM mode, this bit has a different function. If the CTC0 or CTC2 bit is cleared in PWM mode,

the Timer/Counter acts as an up/down counter. If the CTC0 or CTC2 bit is set (one), the

Timer/Counter wraps when it reaches $FF. Refer to page 95 for a detailed description.

• Bits 2,1,0 - CS02, CS01, CS00/ CS22, CS21, CS20: Clock Select Bits 2,1 and 0

The Clock Select bits 2,1 and 0 define the prescaling source of Timer/Counter0 and

Timer/Counter2, see Table 4-13 and Table 4-14.

93

1138H–FPSLI–6/05

Table 4-13. Clock 0 Prescale Select

CS02

CS01

CS00

Description

0

1

0

1

0

1

0

1

0

1

0

1

0

1

Stop, the Timer/Counter0 is stopped

CK

CK/8

CK/64

CK/256

CK/1024

External pin PE0(T0), falling edge

External pin PE0(T0), rising edge

Table 4-14. Clock 2 Prescale Select

CS22

CS21

CS20

Description

0

1

0

1

0

1

0

1

0

1

0

1

0

1

Stop, the Timer/Counter2 is stopped

PCK2

PCK2/8

PCK2/32

PCK2/64

PCK2/128

PCK2/256

PCK2/1024

The Stop condition provides a Timer Enable/Disable function. The prescaled modes are scaled

directly from the CK oscillator clock for Timer/Counter0 and PCK2 for Timer/Counter2. If the

external pin modes are used for Timer/Counter0, transitions on PE0/(T0) will clock the counter

even if the pin is configured as an output. This feature can give the user SW control of the

counting.

Timer Counter0 – TCNT0

Bit

7

6

5

4

3

2

1

0

$32 ($52)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

TCNT0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

Timer/Counter2 – TCNT2

Bit

7

6

5

4

3

2

1

0

$23 ($43)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

TCNT2

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

These 8-bit registers contain the value of the Timer/Counters.

94

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Both Timer/Counters are realized as up or up/down (in PWM mode) counters with read and write

access. If the Timer/Counter is written to and a clock source is selected, it continues counting in

the timer clock cycle following the write operation.

Timer/Counter0 Output Compare Register – OCR0

Bit

7

6

5

4

3

2

1

0

$31 ($51)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

OCR0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

Timer/Counter2 Output Compare Register – OCR2

Bit

7

6

5

4

3

2

1

0

$22 ($42)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

OCR2

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

The output compare registers are 8-bit read/write registers. The Timer/Counter Output Compare

Registers contains the data to be continuously compared with the Timer/Counter. Actions on

compare matches are specified in TCCR0 and TCCR2. A compare match does only occur if the

Timer/Counter counts to the OCR value. A software write that sets Timer/Counter and Output

Compare Register to the same value does not generate a compare match.

A compare match will set the compare interrupt flag in the CPU clock-cycle following the com-

pare event.

4.25.1

Timer/Counter 0 and 2 in PWM Mode

When PWM mode is selected, the Timer/Counter either wraps (overflows) when it reaches $FF

or it acts as an up/down counter.

If the up/down mode is selected, the Timer/Counter and the Output Compare Registers – OCR0

or OCR2 form an 8-bit, free-running, glitch-free and phase correct PWM with outputs on the

PE1(OC0/PWM0) or PE3(OC2/PWM2) pin.

If the overflow mode is selected, the Timer/Counter and the Output Compare Registers – OCR0

or OCR2 form an 8-bit, free-running and glitch-free PWM, operating with twice the speed of the

up/down counting mode.

4.25.2

PWM Modes (Up/Down and Overflow)

The two different PWM modes are selected by the CTC0 or CTC2 bit in the Timer/Counter Con-

trol Registers – TCCR0 or TCCR2 respectively.

If CTC0/CTC2 is cleared and PWM mode is selected, the Timer/Counter acts as an up/down

counter, counting up from $00 to $FF, where it turns and counts down again to zero before the

cycle is repeated. When the counter value matches the contents of the Output Compare Regis-

ter, the PE1(OC0/PWM0) or PE3(OC2/PWM2) pin is set or cleared according to the settings of

the COMn1/COMn0 bits in the Timer/Counter Control Registers TCCR0 or TCCR2.

If CTC0/CTC2 is set and PWM mode is selected, the Timer/Counters will wrap and start count-

ing from $00 after reaching $FF. The PE1(OC0/PWM0) or PE3(OC2/PWM2) pin will be set or

cleared according to the settings of COMn1/COMn0 on a Timer/Counter overflow or when the

counter value matches the contents of the Output Compare Register. Refer to Table 4-15 for

details.

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Table 4-15. Compare Mode Select in PWM Mode

CTCn⁽¹⁾

COMn1⁽¹⁾

COMn0⁽¹⁾

Effect on Compare Pin

Frequency

x⁽²⁾

0

x⁽²⁾

Not connected

–

Cleared on compare match, up-counting. Set

on compare match, down-counting (non-

inverted PWM)

0

1

0

1

f_TCK0/2/510

Cleared on compare match, down-counting.

Set on compare match, up-counting (inverted

PWM)

f_TCK0/2/510

Cleared on compare match,

set on overflow

1

0

1

f_TCK0/2/256

Set on compare match, cleared on overflow

Notes: 1. n = 0 or 2

2. x = don’ t care

In PWM mode, the value to be written to the Output Compare Register is first transferred to a

temporary location, and then latched into the OCR when the Timer/Counter reaches $FF. This

prevents the occurrence of odd-length PWM pulses (glitches) in the event of an unsynchronized

OCR0 or OCR2 write. See Figure 4-29 and Figure 4-30 for examples.

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Figure 4-29. Effects of Unsynchronized OCR Latching in Up/Down Mode

Compare Value Changes

Counter Value

Compare Value

PWM Output OCn⁽¹⁾

Synchronized OCn⁽¹⁾Latch

Compare Value Changes

Counter Value

Compare Value

PWM Output OCn⁽¹⁾

Unsynchronized OCn⁽¹⁾Latch

Glitch

Note:

1. n = 0 or 2

Figure 4-30. Effects of Unsynchronized OCR Latching in Overflow Mode.

Compare Value Changes

Counter Value

Compare Value

PWM Output OCn⁽¹⁾

Synchronized OCn⁽¹⁾Latch

Compare Value Changes

Counter Value

Compare Value

PWM Output OCn⁽¹⁾

Glitch

Unsynchronized OCn⁽¹⁾Latch

Note:

1. n = 0 or 2

During the time between the write and the latch operation, a read from the Output Compare

Registers will read the contents of the temporary location. This means that the most recently

written value always will read out of OCR0 and OCR2.

When the Output Compare Register contains $00 or $FF, and the up/down PWM mode is

selected, the output PE1(OC0/PWM0)/PE3(OC2/PWM2) is updated to Low or High on the next

compare match according to the settings of COMn1/COMn0. This is shown in Table 4-16. In

overflow PWM mode, the output PE1(OC0/PWM0)/PE3(OC2/PWM2) is held Low or High only

when the Output Compare Register contains $FF.

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Table 4-16. PWM Outputs OCRn = $00 or $FF⁽¹⁾

COMn1⁽²⁾

COMn0⁽²⁾

OCRn⁽²⁾

$00

Output PWMn⁽²⁾

1

0

1

L

H

L

$FF

$00

$FF

Notes: 1. n overflow PWM mode, this table is only valid for OCRn = $FF

2. n = 0 or 2

In up/down PWM mode, the Timer Overflow Flag, TOV0 or TOV2, is set when the counter

advances from $00. In overflow PWM mode, the Timer Overflow Flag is set as in normal

Timer/Counter mode. Timer Overflow Interrupts 0 and 2 operate exactly as in normal

Timer/Counter mode, i.e. they are executed when TOV0 or TOV2 are set provided that Timer

Overflow Interrupt and global interrupts are enabled. This does also apply to the Timer Output

Compare flag and interrupt.

Asynchronous Status Register – ASSR

Bit

7

-

6

-

5

-

4

-

3

2

1

0

$26 ($46)

Read/Write

Initial Value

AS2

R/W

0

TCN2UB

OCR2UB TCR2UB

ASSR

R

0

R

0

R

0

R

0

R

0

R

0

R

0

• Bit 7..4 - Res: Reserved Bits

These bits are reserved bits in the FPSLIC and are always read as zero.

• Bit 3 - AS2: Asynchronous Timer/Counter2 Mode

When this bit is cleared (zero) Timer/Counter2 is clocked from the internal system clock, CK. If

AS2 is set, the Timer/Counter2 is clocked from the TOSC1 pin. When the value of this bit is

changed the contents of TCNT2, OCR2 and TCCR2 might get corrupted.

• Bit 2 - TCN2UB: Timer/Counter2 Update Busy

When Timer/Counter2 operates asynchronously and TCNT2 is written, this bit becomes set

(one). When TCNT2 has been updated from the temporary storage register, this bit is cleared

(zero) by the hardware. A logic 0 in this bit indicates that TCNT2 is ready to be updated with a

new value.

• Bit 1 - OCR2UB: Output Compare Register2 Update Busy

When Timer/Counter2 operates asynchronously and OCR2 is written, this bit becomes set

(one). When OCR2 has been updated from the temporary storage register, this bit is cleared

(zero) by the hardware. A logic 0 in this bit indicates that OCR2 is ready to be updated with a

new value.

• Bit 0 - TCR2UB: Timer/Counter Control Register2 Update Busy

When Timer/Counter2 operates asynchronously and TCCR2 is written, this bit becomes set

(one). When TCCR2 has been updated from the temporary storage register, this bit is cleared

(zero) by the hardware. A logic 0 in this bit indicates that TCCR2 is ready to be updated with a

new value.

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If a write is performed to any of the three Timer/Counter2 registers while its update busy flag is

set (one), the updated value might get corrupted and cause an unintentional interrupt to occur.

The mechanisms for reading TCNT2, OCR2 and TCCR2 are different. When reading TCNT2,

the actual timer value is read. When reading OCR2 or TCCR2, the value in the temporary stor-

age register is read.

4.25.3

Asynchronous Operation of Timer/Counter2

When Timer/Counter2 operates asynchronously, some considerations must be taken:

• When switching between asynchronous and synchronous clocking of Timer/Counter2, the

timer registers TCNT2, OCR2 and TCCR2 might get corrupted. A safe procedure for

switching the clock source is:

1. Disable the Timer/Counter2 interrupts by clearing OCIE2 and TOIE2.

2. Select clock source by setting AS2 as appropriate.

3. Write new values to TCNT2, OCR2 and TCCR2.

4. To switch to asynchronous operation: Wait for TCN2UB, OCR2UB, and TCR2UB.

5. Enable interrupts, if needed.

• The oscillator is optimized for use with a 32.768 kHz watch crystal. An external clock signal

applied to this pin goes through the same amplifier having a bandwidth of 256 kHz. The

external clock signal should therefore be in the interval

0 Hz – 1 MHz. The frequency of the clock signal applied to the TOSC1 pin must be lower

than one fourth of the CPU main clock frequency.

• When writing to one of the registers TCNT2, OCR2, or TCCR2, the value is transferred to a

temporary register, and latched after two positive edges on TOSC1. The user should not

write a new value before the contents of the temporary register have been transferred to its

destination. Each of the three mentioned registers have their individual temporary register,

which means that, e.g., writing to TCNT2 does not disturb an OCR2 write in progress. To

detect that a transfer to the destination register has taken place, an Asynchronous Status

Register – ASSR has been implemented.

• When entering Power-save mode after having written to TCNT2, OCR2, or TCCR2, the user

must wait until the written register has been updated if Timer/Counter2 is used to wake-up

the device. Otherwise, the MCU will go to sleep before the changes have had any effect. This

is extremely important if the Output Compare2 interrupt is used to wake-up the device;

Output compare is disabled during write to OCR2 or TCNT2. If the write cycle is not finished

(i.e., the MCU enters Sleep mode before the OCR2UB bit returns to zero), the device will

never get a compare match and the MCU will not wake-up.

• If Timer/Counter2 is used to wake-up the device from Power-save mode, precautions must be

taken if the user wants to re-enter Power-save mode: The interrupt logic needs one TOSC1

cycle to be reset. If the time between wake-up and reentering Power-save mode is less than

one TOSC1 cycle, the interrupt will not occur and the device will fail to wake up. If the user is

in doubt whether the time before re-entering power-save is sufficient, the following algorithm

can be used to ensure that one TOSC1 cycle has elapsed:

1. Write a value to TCCR2, TCNT2, or OCR2.

2. Wait until the corresponding Update Busy flag in ASSR returns to zero.

3. Enter Power-save mode.

• When asynchronous operation is selected, the 32.768 kHz oscillator for Timer/Counter2 is

always running, except in Power-down mode. After a power-up reset or wake-up from power-

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down, the user should be aware of the fact that this oscillator might take as long as one

second to stabilize. Therefore, the contents of all Timer2 registers must be considered lost

after a wake-up from power-down, due to the unstable clock signal. The user is advised to

wait for at least one second before using Timer/Counter2 after power-up or wake-up from

power-down.

• Description of wake-up from Power-save mode when the timer is clocked asynchronously.

When the interrupt condition is met, the wake-up process is started on the following cycle of

the timer clock, that is, the timer is always advanced by at least one before the processor can

read the counter value. The interrupt flags are updated three processor cycles after the

processor clock has started. During these cycles, the processor executes instructions, but

the interrupt condition is not readable, and the interrupt routine has not started yet.

• During asynchronous operation, the synchronization of the interrupt flags for the

asynchronous timer takes three processor cycles plus one timer cycle. The timer is therefore

advanced by at least one before the processor can read the timer value causing the setting of

the interrupt flag. The output compare pin is changed on the timer clock and is not

synchronized to the processor clock.

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4.26 Timer/Counter1

Figure 4-31 shows the block diagram for Timer/Counter1.

Figure 4-31. Timer/Counter1 Block Diagram

T/C1 OVER- T/C1 COMPARE

T/C1 COMPARE

MATCHB IRQ

T/C1 INPUT

CAPTURE IRQ

FLOW IRQ

MATCHA IRQ

TIMER INT. MASK

REGISTER (TIMSK)

TIMER INT. FLAG

REGISTER (TIFR)

T/C1 CONTROL

REGISTER A (TCCR1A)

T/C1 CONTROL

REGISTER B (TCCR1B)

SPECIAL FUNCTIONS

IO REGISTER (SFIOR)

15

8

7

0

CK

T/C1 INPUT CAPTURE REGISTER (ICR1)

CONTROL

LOGIC

T1

CAPTURE

TRIGGER

15

8

7

T/C CLEAR

T/C CLOCK SOURCE

UP/DOWN

TIMER/COUNTER1 (TCNT1)

15

8

7

0

15

8

0

7

16 BIT COMPARATOR

8

7

15

8

7

TIMER/COUNTER1 OUTPUT COMPARE REGISTER A

TIMER/COUNTER1 OUTPUT COMPARE REGISTER B

The 16-bit Timer/Counter1 can select the clock source from CK, prescaled CK, or an external

pin. In addition it can be stopped as described in section “Timer/Counter1 Control Register B –

TCCR1B” on page 104. The different status flags (overflow, compare match and capture event)

are found in the Timer/Counter Interrupt Flag Register – TIFR. Control signals are found in the

Timer/Counter1 Control Registers – TCCR1A and TCCR1B. The interrupt enable/disable set-

tings for Timer/Counter1 are found in the Timer/Counter Interrupt Mask Register – TIMSK.

When Timer/Counter1 is externally clocked, the external signal is synchronized with the oscilla-

tor frequency of the CPU. To assure proper sampling of the external clock, the minimum time

between two external clock transitions must be at least one internal CPU clock period. The

external clock signal is sampled on the rising edge of the internal CPU clock.

The 16-bit Timer/Counter1 features both a high-resolution and a high-accuracy usage with the

lower prescaling opportunities. Similarly, the high-prescaling opportunities makes the

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1138H–FPSLI–6/05

Timer/Counter1 useful for lower speed functions or exact-timing functions with infrequent

actions.

The Timer/Counter1 supports two Output Compare functions using the Output Compare Regis-

ter 1 A and B – OCR1A and OCR1B as the data sources to be compared to the Timer/Counter1

contents. The Output Compare functions include optional clearing of the counter on compareA

match, and actions on the Output Compare pins on both compare matches.

Timer/Counter1 can also be used as a 8-, 9- or 10-bit Pulse Width Modulator. In this mode, the

counter and the OCR1A/OCR1B registers serve as a dual-glitch-free stand-alone PWM with

centered pulses. Alternatively, the Timer/Counter1 can be configured to operate at twice the

speed in PWM mode, but without centered pulses. Refer to page 107 for a detailed description

on this function.

The Input Capture function of Timer/Counter1 provides a capture of the Timer/Counter1 con-

tents to the Input Capture Register – ICR1, triggered by an external event on the Input Capture

Pin – PE7(ICP). The actual capture event settings are defined by the Timer/Counter1 Control

Register – TCCR1B.

Figure 4-32. ICP Pin Schematic Diagram

ICPE

ICPE: Input Capture Pin Enable

If the noise canceler function is enabled, the actual trigger condition for the capture event is

monitored over four samples, and all four must be equal to activate the capture flag.

Timer/Counter1 Control Register A – TCCR1A

Bit

7

6

5

4

3

2

1

0

$2F ($4F)

Read/Write

Initial Value

COM1A1

COM1A0

COM1B1

COM1B0

FOC1A

R/w

0

FOC1B

R/W

0

PWM11

R/W

0

PWM10

R/W

0

TCCR1A

R/W

0

R/W

0

R/W

0

R/W

0

• Bits 7,6 - COM1A1, COM1A0: Compare Output Mode1A, Bits 1 and 0

The COM1A1 and COM1A0 control bits determine any output pin action following a compare

match in Timer/Counter1. Any output pin actions affect pin OC1A – Output CompareA pin PE6.

This is an alternative function to an I/O port, and the corresponding direction control bit must be

set (one) to control an output pin. The control configuration is shown in Table 4-17.

• Bits 5,4 - COM1B1, COM1B0: Compare Output Mode1B, Bits 1 and 0

The COM1B1 and COM1B0 control bits determine any output pin action following a compare

match in Timer/Counter1. Any output pin actions affect pin OC1B – Output CompareB pin PE5.

This is an alternative function to an I/O port, and the corresponding direction control bit must be

set (one) to control an output pin. The following control configuration is given:

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AT94KAL Series FPSLIC

Table 4-17. Compare 1 Mode Select⁽¹⁾

COM1X1⁽²⁾

COM1X0⁽²⁾

Description

0

1

0

1

0

1

Timer/Counter1 disconnected from output pin OC1X

Toggles the OC1X output line

Clears the OC1X output line (to zero)

Sets the OC1X output line (to one)

Notes: 1. In PWM mode, these bits have a different function. Refer to Table 4-21 for a detailed

description.

2. X = A or B

• Bit 3 - FOC1A: Force Output Compare1A

Writing a logic 1 to this bit forces a change in the compare match output pin PE6 according to

the values already set in COM1A1 and COM1A0. If the COM1A1 and COM1A0 bits are written

in the same cycle as FOC1A, the new settings will not take effect until next compare match or

forced compare match occurs. The Force Output Compare bit can be used to change the output

pin without waiting for a compare match in the timer. The automatic action programmed in

COM1A1 and COM1A0 happens as if a Compare Match had occurred, but no interrupt is gener-

ated and it will not clear the timer even if CTC1 in TCCR1B is set. The FOC1A bit will always be

read as zero. The setting of the FOC1A bit has no effect in PWM mode.

• Bit 2 - FOC1B: Force Output Compare1B

Writing a logic 1 to this bit forces a change in the compare match output pin PE5 according to

the values already set in COM1B1 and COM1B0. If the COM1B1 and COM1B0 bits are written

in the same cycle as FOC1B, the new settings will not take effect until next compare match or

forced compare match occurs. The Force Output Compare bit can be used to change the output

pin without waiting for a compare match in the timer. The automatic action programmed in

COM1B1 and COM1B0 happens as if a Compare Match had occurred, but no interrupt is gener-

ated. The FOC1B bit will always be read as zero. The setting of the FOC1B bit has no effect in

PWM mode.

• Bits 1..0 - PWM11, PWM10: Pulse Width Modulator Select Bits

These bits select PWM operation of Timer/Counter1 as specified in Table 4-18. This mode is

described on page 107.

Table 4-18. PWM Mode Select

PWM11

PWM10

Description

0

1

0

1

0

1

PWM operation of Timer/Counter1 is disabled

Timer/Counter1 is an 8-bit PWM

Timer/Counter1 is a 9-bit PWM

Timer/Counter1 is a 10-bit PWM

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Timer/Counter1 Control Register B – TCCR1B

Bit

7

6

5

4

-

3

2

1

0

$2E ($4E)

Read/Write

Initial Value

ICNC1

R/W

0

ICES1

R/W

0

ICPE

R/W

0

CTC1

R/W

0

CS12

R/W

0

CS11

R/W

0

CS10

R/W

0

TCCR1B

R

0

• Bit 7 - ICNC1: Input Capture1 Noise Canceler (4 CKs)

When the ICNC1 bit is cleared (zero), the input capture trigger noise canceler function is dis-

abled. The input capture is triggered at the first rising/falling edge sampled on the PE7(ICP) –

input capture pin – as specified. When the ICNC1 bit is set (one), four successive samples are

measured on the PE7(ICP) – input capture pin, and all samples must be High/Low according to

the input capture trigger specification in the ICES1 bit. The actual sampling frequency is XTAL

clock frequency.

• Bit 6 - ICES1: Input Capture1 Edge Select

While the ICES1 bit is cleared (zero), the Timer/Counter1 contents are transferred to the Input

Capture Register – ICR1 – on the falling edge of the input capture pin – PE7(ICP). While the

ICES1 bit is set (one), the Timer/Counter1 contents are transferred to the Input Capture Register

– ICR1 – on the rising edge of the input capture pin – PE7(ICP).

• Bit 5 - ICPE: Input Captive Pin Enable

This bit must be set by the user to enable the Input Capture Function of timer1. Disabling pre-

vents unnecessary register copies during normal use of the PE7 port.

• Bit 4 - Res: Reserved Bit

This bit is reserved in the FPSLIC and will always read zero.

• Bit 3 - CTC1: Clear Timer/Counter1 on Compare Match

When the CTC1 control bit is set (one), the Timer/Counter1 is reset to $0000 in the clock cycle

after a compareA match. If the CTC1 control bit is cleared, Timer/Counter1 continues counting

and is unaffected by a compare match. When a prescaling of 1 is used, and the compareA reg-

ister is set to C, the timer will count as follows if CTC1 is set:

... | C-1 | C | 0 | 1 | ...

When the prescaler is set to divide by 8, the timer will count like this:

... | C-1, C-1, C-1, C-1, C-1, C-1, C-1, C-1 | C, C, C, C, C, C, C, C | 0, 0, 0, 0, 0, 0, 0, 0 | ...

In PWM mode, this bit has a different function. If the CTC1 bit is cleared in PWM mode, the

Timer/Counter1 acts as an up/down counter. If the CTC1 bit is set (one), the Timer/Counter

wraps when it reaches the TOP value. Refer to page 107 for a detailed description.

• Bits 2,1,0 - CS12, CS11, CS10: Clock Select1, Bits 2, 1 and 0

The Clock Select1 bits 2,1 and 0 define the prescaling source of Timer/Counter1.

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Table 4-19. Clock 1 Prescale Select

CS12

CS11

CS10

Description

0

1

0

1

0

1

0

1

0

1

0

1

0

1

Stop, the Timer/Counter1 is stopped

CK

CK/8

CK/64

CK/256

CK/1024

External pin PE4 (T1), falling edge

External pin PE4 (T1), rising edge

The Stop condition provides a Timer Enable/Disable function. The CK down-divided modes are

scaled directly from the CK oscillator clock. If the external pin modes are used for

Timer/Counter1, transitions on PE4/(T1) will clock the counter even if the pin is configured as an

output. This feature can give the user SW control of the counting.

Timer/Counter1 Register – TCNT1H AND TCNT1L

Bit

15

14

13

12

11

10

9

8

$2D ($4D)

$2C ($4C)

MSB

TCNT1H

TCNT1L

LSB

0

7

6

5

4

3

2

1

Read/Write

Initial Value

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

This 16-bit register contains the prescaled value of the 16-bit Timer/Counter1. To ensure that

both the High and low bytes are read and written simultaneously when the CPU accesses these

registers, the access is performed using an 8-bit temporary register (TEMP). This temporary reg-

ister is also used when accessing OCR1A, OCR1B and ICR1. If the main program and also

interrupt routines perform access to registers using TEMP, interrupts must be disabled during

access from the main program and interrupt routines.

4.26.1

4.26.2

TCNT1 Timer/Counter1 Write

When the CPU writes to the high byte TCNT1H, the written data is placed in the TEMP register.

Next, when the CPU writes the low byte TCNT1L, this byte of data is combined with the byte

data in the TEMP register, and all 16 bits are written to the TCNT1 Timer/Counter1 register

simultaneously. Consequently, the high byte TCNT1H must be accessed first for a full 16-bit reg-

ister write operation.

TCNT1 Timer/Counter1 Read

When the CPU reads the low byte TCNT1L, the data of the low byte TCNT1L is sent to the CPU

and the data of the high byte TCNT1H is placed in the TEMP register. When the CPU reads the

data in the high byte TCNT1H, the CPU receives the data in the TEMP register. Consequently,

the low byte TCNT1L must be accessed first for a full 16-bit register read operation.

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1138H–FPSLI–6/05

The Timer/Counter1 is realized as an up or up/down (in PWM mode) counter with read and write

access. If Timer/Counter1 is written to and a clock source is selected, the Timer/Counter1 con-

tinues counting in the timer clock-cycle after it is preset with the written value.

Timer/Counter1 Output Compare Register – OCR1AH AND OCR1AL

Bit

15

14

13

12

11

10

9

8

$2B ($4B)

$2A ($4A)

MSB

OCR1AH

OCR1AL

LSB

0

7

6

5

4

3

2

1

Read/Write

Initial Value

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

Timer/Counter1 Output Compare Register – OCR1BH AND OCR1BL

Bit

15

14

13

12

11

10

9

8

$29 ($49)

$28 ($48)

MSB

OCR1BH

OCR1BL

LSB

0

7

6

5

4

3

2

1

Read/Write

Initial Value

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

The output compare registers are 16-bit read/write registers.

The Timer/Counter1 Output Compare Registers contain the data to be continuously compared

with Timer/Counter1. Actions on compare matches are specified in the Timer/Counter1 Control

and Status register. A compare match does only occur if Timer/Counter1 counts to the OCR

value. A software write that sets TCNT1 and OCR1A or OCR1B to the same value does not gen-

erate a compare match.

A compare match will set the compare interrupt flag in the CPU clock cycle following the com-

pare event.

Since the Output Compare Registers – OCR1A and OCR1B – are 16-bit registers, a temporary

register TEMP is used when OCR1A/B are written to ensure that both bytes are updated simul-

taneously. When the CPU writes the high byte, OCR1AH or OCR1BH, the data is temporarily

stored in the TEMP register. When the CPU writes the low byte, OCR1AL or OCR1BL, the

TEMP register is simultaneously written to OCR1AH or OCR1BH. Consequently, the high byte

OCR1AH or OCR1BH must be written first for a full 16-bit register write operation.

The TEMP register is also used when accessing TCNT1, and ICR1. If the main program and

also interrupt routines perform access to registers using TEMP, interrupts must be disabled dur-

ing access from the main program and interrupt routines.

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AT94KAL Series FPSLIC

Timer/Counter1 Input Capture Register – ICR1H AND ICR1L

Bit

15

14

13

12

11

10

9

8

$25 ($45)

$24 ($44)

MSB

ICR1H

ICR1L

LSB

0

7

6

5

4

3

2

1

Read/Write

Initial Value

R

0

R

0

R

0

R

0

R

0

R

0

R

0

R

0

The input capture register is a 16-bit read-only register.

When the rising or falling edge (according to the input capture edge setting – ICES1) of the sig-

nal at the input capture pin – PE7(ICP) – is detected, the current value of the Timer/Counter1

Register – TCNT1 is transferred to the Input Capture Register – ICR1. In the same cycle, the

input capture flag – ICF1 – is set (one).

Since the Input Capture Register – ICR1 – is a 16-bit register, a temporary register TEMP is

used when ICR1 is read to ensure that both bytes are read simultaneously. When the CPU

reads the low byte ICR1L, the data is sent to the CPU and the data of the high byte ICR1H is

placed in the TEMP register. When the CPU reads the data in the high byte ICR1H, the CPU

receives the data in the TEMP register. Consequently, the low byte ICR1L must be accessed

first for a full 16-bit register read operation.

The TEMP register is also used when accessing TCNT1, OCR1A and OCR1B. If the main pro-

gram and also interrupt routines perform access to registers using TEMP, interrupts must be

disabled during access from the main program and interrupt routine.

4.26.3

Timer/Counter1 in PWM Mode

When the PWM mode is selected, Timer/Counter1 and the Output Compare Register1A –

OCR1A and the Output Compare Register1B – OCR1B, form a dual 8-, 9- or 10-bit, free-run-

ning, glitch-free and phase correct PWM with outputs on the PE6(OC1A) and PE5(OC1B) pins.

In this mode the Timer/Counter1 acts as an up/down counter, counting up from $0000 to TOP

(see Table 4-20), where it turns and counts down again to zero before the cycle is repeated.

When the counter value matches the contents of the 8, 9 or 10 least significant bits (depends of

the resolution) of OCR1A or OCR1B, the PD6(OC1A)/PE5(OC1B) pins are set or cleared

according to the settings of the COM1A1/COM1A0 or COM1B1/COM1B0 bits in the

Timer/Counter1 Control Register TCCR1A. Refer to Table 4-21 for details.

Alternatively, the Timer/Counter1 can be configured to a PWM that operates at twice the speed

as in the mode described above. Then the Timer/Counter1 and the Output Compare Register1A

– OCR1A and the Output Compare Register1B – OCR1B, form a dual 8-, 9- or 10-bit, free-run-

ning and glitch-free PWM with outputs on the PE6(OC1A) and PE5(OC1B) pins.

As shown in Table 4-20, the PWM operates at either 8-, 9- or 10-bit resolution. Note the unused

bits in OCR1A, OCR1B and TCNT1 will automatically be written to zero by the hardware. For

example, bit 9 to 15 will be set to zero in OCR1A, OCR1B and TCNT1 if the 9-bit PWM resolu-

tion is selected. This makes it possible for the user to perform read-modify-write operations in

any of the three resolution modes and the unused bits will be treated as “don’t care”.

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Table 4-20. Timer TOP Values and PWM Frequency

CTC1

PWM11

PWM10

PWM Resolution

Timer TOP Value

$00FF (255)

$01FF (511)

$03FF(1023)

$00FF (255)

$01FF (511)

$03FF(1023)

Frequency

0

1

0

1

0

1

0

1

0

1

8-bit

9-bit

f_TCK1/510

f

_TCK1/1022

f_TCK1/2046

_TCK1/256

10-bit

8-bit

f

9-bit

f_TCK1/512

10-bit

f_TCK1/1024

Table 4-21. Compare1 Mode Select in PWM Mode

OTC1⁽¹⁾

COM1X1⁽¹⁾

COM1X0⁽¹⁾

Effect on OCX1

x⁽²⁾

0

x⁽²⁾

Not connected

Cleared on compare match, up-counting. Set on

compare match, down-counting (non-inverted PWM)

0

1

0

1

Cleared on compare match, down-counting. Set on

compare match, up-counting (inverted PWM)

1

0

1

Cleared on Compare Match, Set on overflow

Set on Compare Match, cleared on overflow

Notes: 1. X = A or B

2. x = Don’t care

In the PWM mode, the 8, 9 or 10 least significant OCR1A/OCR1B bits (depends of resolution),

when written, are transferred to a temporary location. They are latched when Timer/Counter1

reaches the value TOP. This prevents the occurrence of odd-length PWM pulses (glitches) in

the event of an unsynchronized OCR1A/OCR1B write. See Figure 4-33 and Figure 4-34 for an

example in each mode.

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Figure 4-33. Effects on Unsynchronized OCR1 Latching

Compare Value Changes

Counter alue

V

Compare V

alue

OutputOC1X⁽¹⁾

PWM

Synchronized

OCR1X⁽¹⁾Latch

Compare Value Changes

Counter

Value

Compare Value

PWM OutputOC1X⁽¹⁾

OCR1X⁽¹⁾Latch

Glitch

Unsynchronized

Note:

1. X = A or B

Figure 4-34. Effects of Unsynchronized OCR1 Latching in Overflow Mode

Compare Value Changes

PWM Output OC1x⁽¹⁾

Synchronized OC1x⁽¹⁾Latch

Compare Value Changes

PWM Output OC1x⁽¹⁾

Unsynchronized OC1x⁽¹⁾Latch

Note:

1. X = A or B

During the time between the write and the latch operation, a read from OCR1A or OCR1B will

read the contents of the temporary location. This means that the most recently written value

always will read out of OCR1A/B.

When the OCR1X contains $0000 or TOP, and the up/down PWM mode is selected, the output

OC1A/OC1B is updated to Low or High on the next compare match according to the settings of

COM1A1/COM1A0 or COM1B1/COM1B0. This is shown in Table 4-22. In overflow PWM mode,

the output OC1A/OC1B is held Low or High only when the Output Compare Register contains

TOP.

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Table 4-22. PWM Outputs OCR1X = $0000 or TOP⁽¹⁾

COM1X1⁽²⁾

COM1X0⁽²⁾

OCR1X⁽²⁾

$0000

TOP

Output OC1X⁽²⁾

1

0

1

L

H

L

$0000

TOP

Notes: 1. In overflow PWM mode, this table is only valid for OCR1X = TOP.

2. X = A or B

In up/down PWM mode, the Timer Overflow Flag1, TOV1, is set when the counter advances

from $0000. In overflow PWM mode, the Timer Overflow flag is set as in normal Timer/Counter

mode. Timer Overflow Interrupt1 operates exactly as in normal Timer/Counter mode, i.e., it is

executed when TOV1 is set provided that Timer Overflow Interrupt1 and global interrupts are

enabled. This also applies to the Timer Output Compare1 flags and interrupts.

4.27 Watchdog Timer

The Watchdog Timer is clocked from a separate on-chip oscillator which runs at 1 MHz. This is

the typical value at V_CC= 3.3V. See characterization data for typical values at other V_CClevels.

By controlling the Watchdog Timer prescaler, the watchdog reset interval can be adjusted, see

Table 4-23 on page 111 for a detailed description. The WDR (watchdog reset) instruction resets

the Watchdog Timer. Eight different clock cycle periods can be selected to determine the reset

period. If the reset period expires without another watchdog reset, the FPSLIC resets and exe-

cutes from the reset vector.

To prevent unintentional disabling of the watchdog, a special turn-off sequence must be followed

when the watchdog is disabled, see Figure 4-35.

Figure 4-35. Watchdog Timer

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Watchdog Timer Control Register – WDTCR

Bit

7

-

6

-

5

-

4

3

2

1

0

$21 ($41)

Read/Write

Initial Value

WDTOE

R/W

0

WDE

R/W

0

WDP2

R/W

0

WDP1

R/W

0

WDP0

R/W

0

WDTCR

R

0

R

0

R

0

• Bits 7..5 - Res: Reserved Bits

These bits are reserved bits in the FPSLIC and will always read as zero.

• Bit 4 - WDTOE: Watchdog Turn-off Enable

This bit must be set (one) when the WDE bit is cleared. Otherwise, the watchdog will not be dis-

abled. Once set, the hardware will clear this bit to zero after four clock cycles. Refer to the

description of the WDE bit below for a watchdog disable procedure.

• Bit 3 - WDE: Watchdog Enable

When the WDE is set (one) the Watchdog Timer is enabled, but if the WDE is cleared (zero), the

Watchdog Timer function is disabled. WDE can only be cleared if the WDTOE bit is set (one). To

disable an enabled Watchdog Timer, the following procedure must be followed:

1. In the same operation, write a logic 1 to WDTOE and WDE. A logic 1 must be written

to WDE even though it is set to one before the disable operation starts.

2. Within the next four clock cycles, write a logic 0 to WDE. This disables the watchdog.

• Bits 2..0 - WDP2, WDP1, WDP0: Watchdog Timer Prescaler 2, 1 and 0

The WDP2, WDP1 and WDP0 bits determine the Watchdog Timer prescaling when the Watch-

dog Timer is enabled. The different prescaling values and their corresponding Time-out periods

are shown in Table 4-23.

Table 4-23. Watchdog Timer Prescale Select

Number of WDT

Typical Time-out

at V_CC= 3.0V

WDP2

WDP1

WDP0

Oscillator Cycles⁽¹⁾

0

1

0

1

0

1

0

1

0

1

0

1

0

1

16K

32K

15 ms

30 ms

60 ms

0.12s

0.24s

0.49s

0.97s

1.9s

64K

128K

256K

512K

1,024K

2,048K

Note:

1. The frequency of the watchdog oscillator is voltage dependent as shown in the Electrical Char-

acteristics section. The WDR (watchdog reset) instruction should always be executed before

the Watchdog Timer is enabled. This ensures that the reset period will be in accordance with

the Watchdog Timer prescale settings. If the Watchdog Timer is enabled without reset, the

Watchdog Timer may not start counting from zero.

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4.28 Multiplier

The multiplier is capable of multiplying two 8-bit numbers, giving a 16-bit result using only two

clock cycles. The multiplier can handle both signed and unsigned integer and fractional numbers

without speed or code size penalty. Below are some examples of using the multiplier for 8-bit

arithmetic.

To be able to use the multiplier, six new instructions are added to the AVR instruction set. These

are:

• MUL, multiplication of unsigned integers

• MULS, multiplication of signed integers

• MULSU, multiplication of a signed integer with an unsigned integer

• FMUL, multiplication of unsigned fractional numbers

• FMULS, multiplication of signed fractional numbers

• FMULSU, multiplication of a signed fractional number and with an unsigned fractional

number

The MULSU and FMULSU instructions are included to improve the speed and code density for

multiplication of 16-bit operands. The second section will show examples of how to efficiently

use the multiplier for 16-bit arithmetic.

The component that makes a dedicated digital signal processor (DSP) specially suitable for sig-

nal processing is the multiply-accumulate (MAC) unit. This unit is functionally equivalent to a

multiplier directly connected to an arithmetic logic unit (ALU). The FPSLIC-based AVR Core is

designed to give FPSLIC the ability to effectively perform the same multiply-accumulate

operation.

The multiply-accumulate operation (sometimes referred to as multiply-add operation) has one

critical drawback. When adding multiple values to one result variable, even when adding positive

and negative values to some extent, cancel each other; the risk of the result variable to overrun

its limits becomes evident, i.e. if adding 1 to a signed byte variable that contains the value +127,

the result will be -128 instead of +128. One solution often used to solve this problem is to intro-

duce fractional numbers, i.e. numbers that are less than 1 and greater than or equal to -1. Some

issues regarding the use of fractional numbers are discussed.

A list of all implementations with key performance specifications is given in Table 4-24.

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Table 4-24. Performance Summary

8-bit x 8-bit Routines:

Word (Cycles)

1 (2)

Unsigned Multiply 8 x 8 = 16 bits

Signed Multiply 8 x 8 = 16 bits

1 (2)

Fractional Signed/Unsigned Multiply 8 x 8 = 16 bits

Fractional Signed Multiply-accumulate 8 x 8 + = 16 bits

16-bit x 16-bit Routines:

1 (2)

3 (4)

Word (Cycles)

6 (9)

Signed/Unsigned Multiply 16 x 16 = 32 bits

UnSigned Multiply 16 x 16 = 32 bits

Signed Multiply 16 x 16 = 32 bits

13 (17)

15 (19)

19 (23)

16 (20)

Signed Multiply-accumulate 16 x 16 + = 32 bits

Fractional Signed Multiply 16 x 16 = 32 bits

Fractional Signed Multiply-accumulate 16 x 16 + = 32 bits

21 (25)

4.28.1

8-bit Multiplication

Doing an 8-bit multiply using the hardware multiplier is simple: just load the operands into two

registers (or only one for square multiply) and execute one of the multiply instructions. The result

will be placed in register pair R1:R0. However, note that only the MUL instruction does not have

register usage restrictions. Figure 4-36 shows the valid (operand) register usage for each of the

multiply instructions.

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4.28.1.1

Example 1 – Basic Usage

The first example shows an assembly code that reads the port B input value and multiplies this

value with a constant (5) before storing the result in register pair R17:R16.

in

r16,PINB

; Read pin values

; Load 5 into r17

; r1:r0 = r17 * r16

ldi r17,5

mul r16,r17

movw r17:r16,r1:r0; Move the result to the r17:r16

; register pair

Note the use of the MOVW instruction. This example is valid for all of the multiply instructions.

Figure 4-36. Valid Register Usage

MUL

MULS

MULSU

FMUL

FMULS

FMULSU

R0

R1

R2

R3

R4

R5

R6

R7

R8

R9

R10

R11

R12

R13

R14

R15

R16

R17

R18

R19

R20

R21

R22

R23

R24

R25

R26

R27

R28

R29

R30

R31

R16

R17

R18

R19

R20

R21

R22

R23

R24

R25

R26

R27

R28

R29

R30

R31

R16

R17

R18

R19

R20

R21

R22

R23

4.28.1.2

Example 2 – Special Cases

This example shows some special cases of the MUL instruction that are valid.

lds r0,variableA ; Load r0 with SRAM variable A

lds r1,variableB ; Load r1 with SRAM variable B

mul r1,r0

; r1:r0 = variable A * variable B

lds r0,variableA ; Load r0 with SRAM variable A

mul r0,r0 ; r0:r0 = square(variable A)

Even though the operand is put in the result register pair R1:R0, the operation gives the correct

result since R1 and R0 are fetched in the first clock cycle and the result is stored back in the sec-

ond clock cycle.

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4.28.1.3

Example 3 – Multiply-accumulate Operation

The final example of 8-bit multiplication shows a multiply-accumulate operation. The general for-

mula can be written as:

c(n) = a(n) × b + c(n – 1)

; r17:r16 = r18 * r19 + r17:r16

in

r18,PINB; Get the current pin value on port B

; Load constant b into r19

ldi r19,b

muls r19,r18 ; r1:r0 = variable A * variable B

add r16,r0 ; r17:r16 += r1:r0

adc r17,r1

Typical applications for the multiply-accumulate operation are FIR (Finite Impulse Response)

and IIR (Infinite Impulse Response) filters, PID regulators and FFT (Fast Fourier Transform). For

these applications the FMULS instruction is particularly useful. The main advantage of using the

FMULS instruction instead of the MULS instruction is that the 16-bit result of the FMULS opera-

tion always may be approximated to a (well-defined) 8-bit format, see “Using Fractional

Numbers” on page 118.

4.28.2

16-bit Multiplication

The new multiply instructions are specifically designed to improve 16-bit multiplication. This sec-

tion presents solutions for using the hardware multiplier to do multiplication with 16-bit operands.

Figure 4-37 schematically illustrates the general algorithm for multiplying two 16-bit numbers

with a 32-bit result (C = A • B). AH denotes the high byte and AL the low byte of the A operand.

CMH denotes the middle high byte and CML the middle low byte of the result C. Equal notations

are used for the remaining bytes.

The algorithm is basic for all multiplication. All of the partial 16-bit results are shifted and added

together. The sign extension is necessary for signed numbers only, but note that the carry prop-

agation must still be done for unsigned numbers.

Figure 4-37. 16-bit Multiplication, General Algorithm

AH AL

X

BH BL

AL * BL

(sign ext)

(sign

ext)

AL * BH

AH * BL

+

(sign

ext)

AH * BH

CMH CML

CH

CL

=

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4.28.3

16-bit x 16-bit = 16-bit Operation

This operation is valid for both unsigned and signed numbers, even though only the unsigned

multiply instruction (MUL) is needed, see Figure 4-38. A mathematical explanation is given:

When A and B are positive numbers, or at least one of them is zero, the algorithm is clearly cor-

rect, provided that the product C = A • B is less than 2¹⁶if the product is to be used as an

unsigned number, or less than 2¹⁵if the product is to be used as a signed number.

When both factors are negative, the two’s complement notation is used:

A = 2¹⁶- |A| and B = 2¹⁶- |B|:

C = A • B = (2¹⁶- |A|) • (2¹⁶- |B|) = |A • B| + 2³²- 2¹⁶• (|A| + |B|)

Here we are only concerned with the 16 LSBs; the last part of this sum will be discarded and we

will get the (correct) result C = |A • B|.

Figure 4-38. 16-bit Multiplication, 16-bit Result

AH AL

X

BH BL

AL * BL

1

2

3

AL * BH

AH * BL

+

CH CL

=

When one factor is negative and one factor is positive, for example, A is negative and B is

positive:

C = A • B = (2¹⁶- |A|) • |B| = (2¹⁶• |B|) - |A • B| = (2¹⁶- |A • B|) + 2¹⁶• (|B| - 1)

The MSBs will be discarded and the correct two’s complement notation result will be

C = 2¹⁶- |A • B|.

The product must be in the range 0 ≤ C ≤ 2¹⁶- 1 if unsigned numbers are used, and in the range

-2¹⁵≤ C ≤ 2¹⁵- 1 if signed numbers are used.

When doing integer multiplication in C language, this is how it is done. The algorithm can be

expanded to do 32-bit multiplication with 32-bit result.

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4.28.4

16-bit x 16-bit = 32-bit Operation

4.28.4.1

Example 4 – Basic Usage 16-bit x 16-bit = 32-bit Integer Multiply

Below is an example of how to call the 16 x 16 = 32 multiply subroutine. This is also illustrated in

Figure 4-39.

ldi R23,HIGH(672)

ldi R22,LOW(672) ; Load the number 672 into r23:r22

ldi R21,HIGH(1844)

ldi R20,LOW(1844); Load the number 1844 into r21:r20

callmul16x16_32 ; Call 16bits x 16bits = 32bits

; multiply routine

Figure 4-39. 16-bit Multiplication, 32-bit Result

AH AL

X

BH BL

(sign

ext)

AL * BH

AH * BL

3

(sign

ext)

4

+

AH * BH AL * BL

1 + 2

+

CMH CML

CH

CL

=

The 32-bit result of the unsigned multiplication of 672 and 1844 will now be in the registers

R19:R18:R17:R16. If “muls16x16_32” is called instead of “mul16x16_32”, a signed multiplication

will be executed. If “mul16x16_16” is called, the result will only be 16 bits long and will be stored

in the register pair R17:R16. In this example, the 16-bit result will not be correct.

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4.28.5

16-bit Multiply-accumulate Operation

Figure 4-40. 16-bit Multiplication, 32-bit Accumulated Result

AH AL

X

BH BL

AL * BL

(sign ext)

(sign

ext)

AL * BH

AH * BL

+

(sign

ext)

AH * BH

CMH CML

CH

CL ( Old )

CL ( New )

CMH CML

=

4.28.6

Using Fractional Numbers

Unsigned 8-bit fractional numbers use a format where numbers in the range [0, 2> are allowed.

Bits 6 - 0 represent the fraction and bit 7 represents the integer part (0 or 1), i.e. a 1.7 format.

The FMUL instruction performs the same operation as the MUL instruction, except that the result

is left-shifted 1 bit so that the high byte of the 2-byte result will have the same 1.7 format as the

operands (instead of a 2.6 format). Note that if the product is equal to or higher than 2, the result

will not be correct.

To fully understand the format of the fractional numbers, a comparison with the integer number

format is useful: Table 20 illustrates the two 8-bit unsigned numbers formats. Signed fractional

numbers, like signed integers, use the familiar two’s complement format. Numbers in the range

[-1, 1> may be represented using this format.

If the byte “1011 0010” is interpreted as an unsigned integer, it will be interpreted as 128 + 32 +

16 + 2 = 178. On the other hand, if it is interpreted as an unsigned fractional number, it will be

interpreted as 1 + 0.25 + 0.125 + 0.015625 = 1.390625. If the byte is assumed to be a signed

number, it will be interpreted as 178 - 256 = -122 (integer) or as 1.390625 - 2 = -0.609375 (frac-

tional number).

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Table 4-25. Comparison of Integer and Fractional Formats

Unsigned Integer

Bit Significance

Unsigned Fractional Number

Bit Significance

Bit Number

7

6

5

4

3

2

1

0

2⁷= 128

2⁶= 64

2⁵= 32

2⁴= 16

2³= 8

2⁰= 1

2^-1= 0.5

2^-2= 0.25

2^-3= 0.125

2^-4= 0.0625

2^-5= 0.3125

2^-6= 0.015625

2^-7= 0.0078125

2²= 4

2¹= 2

2⁰= 1

Using the FMUL, FMULS and FMULSU instructions should not be more complex than the MUL,

MULS and MULSU instructions. However, one potential problem is to assign fractional variables

right values in a simple way. The fraction 0.75 (= 0.5 + 0.25) will, for example, be “0110 0000” if

8 bits are used.

To convert a positive fractional number in the range [0, 2> (for example 1.8125) to the format

used in the AVR, the following algorithm, illustrated by an example, should be used:

Is there a “1” in the number?

Yes, 1.8125 is higher than or equal to 1.

Byte is now “1xxx xxxx”

Is there a “0.5” in the rest?

0.8125 / 0.5 = 1.625

Yes, 1.625 is higher than or equal to 1.

Byte is now “11xx xxxx”

Is there a “0.25” in the rest?

0.625 / 0.5 = 1.25

Yes, 1.25 is higher than or equal to 1.

Byte is now “111x xxxx”

Is there a “0.125” in the rest?

0.25 / 0.5 = 0.5

No, 0.5 is lower than 1.

Byte is now “1110 xxxx”

Is there a “0.0625” in the rest?

0.5 / 0.5 = 1

Yes, 1 is higher than or equal to 1.

Byte is now “1110 1xxx”

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Since we do not have a rest, the remaining three bits will be zero, and the final result is “1110

1000”, which is 1 + 0.5 + 0.25 + 0.0625 = 1.8125.

To convert a negative fractional number, first add 2 to the number and then use the same algo-

rithm as already shown.

16-bit fractional numbers use a format similar to that of 8-bit fractional numbers; the high 8 bits

have the same format as the 8-bit format. The low 8 bits are only an increase of accuracy of the

8-bit format; while the 8-bit format has an accuracy of ± 2^-8, the16-bit format has an accuracy of

± 2^-16. Then again, the 32-bit fractional numbers are an increase of accuracy to the

16-bit fractional numbers. Note the important difference between integers and fractional num-

bers when extra byte(s) are used to store the number: while the accuracy of the numbers is

increased when fractional numbers are used, the range of numbers that may be represented is

extended when integers are used.

As mentioned earlier, using signed fractional numbers in the range [-1, 1> has one main advan-

tage to integers: when multiplying two numbers in the range [-1, 1>, the result will be in the

range [-1, 1], and an approximation (the highest byte(s)) of the result may be stored in the same

number of bytes as the factors, with one exception: when both factors are -1, the product should

be 1, but since the number 1 cannot be represented using this number format, the FMULS

instruction will instead place the number -1 in R1:R0. The user should therefore assure that at

least one of the operands is not -1 when using the FMULS instruction. The

16-bit x 16-bit fractional multiply also has this restriction.

4.28.6.1

Example 5 – Basic Usage 8-bit x 8-bit = 16-bit Signed Fractional Multiply

This example shows an assembly code that reads the port E input value and multiplies this

value with a fractional constant (-0.625) before storing the result in register pair R17:R16.

in

r16,PINE

; Read pin values

ldi r17,$B0

fmulsr16,r17

; Load -0.625 into r17

; r1:r0 = r17 * r16

movw r17:r16,r1:r0; Move the result to the r17:r16

; register pair

Note that the usage of the FMULS (and FMUL) instructions is very similar to the usage of the

MULS and MUL instructions.

4.28.6.2

Example 6 – Multiply-accumulate Operation

The example below uses data from the ADC. The ADC should be configured so that the format

of the ADC result is compatible with the fractional two’s complement format. For the

ATmega83/163, this means that the ADLAR bit in the ADMUX I/O register is set and a differen-

tial channel is used. The ADC result is normalized to one.

ldir23,$62

ldir22,$C0

; Load highbyte of

; fraction 0.771484375

; Load lowbyte of

; fraction 0.771484375

; Get lowbyte of ADC conversion

; Get highbyte of ADC conversion

in r20,ADCL

in r21,ADCH

callfmac16x16_32 ;Call routine for signed fractional

; multiply accumulate

120

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

The registers R19:R18:R17:R16 will be incremented with the result of the multiplication of

0.771484375 with the ADC conversion result. In this example, the ADC result is treated as a

signed fraction number. We could also treat it as a signed integer and call it “mac16x16_32”

instead of “fmac16x16_32”. In this case, the 0.771484375 should be replaced with an integer.

4.28.7

Implementations

4.28.7.1

mul16x16_16

Description

Multiply of two 16-bit numbers with a 16-bit result.

Usage

R17:R16 = R23:R22 • R21:R20

Statistics

Cycles: 9 + ret

Words: 6 + ret

Register usage: R0, R1 and R16 to R23 (8 registers)⁽¹⁾

Note:

1. Full orthogonality, i.e., any register pair can be used as long as the result and the two oper-

ands do not share register pairs. The routine is non-destructive to the operands.

mul16x16_16:

mul r22, r20

movw r17:r16, r1:r0

; al * bl

; ah * bl

; bh * al

mul

add

mul

add

ret

r23, r20

r17, r0

r21, r22

r17, r0

121

1138H–FPSLI–6/05

4.28.7.2

mul16x16_32

Description

Unsigned multiply of two 16-bit numbers with a 32-bit result.

Usage

R19:R18:R17:R16 = R23:R22 • R21:R20

Statistics

Cycles: 17 + ret

Words: 13 + ret

Register usage: R0 to R2 and R16 to R23 (11 registers)⁽¹⁾

Note:

1. Full orthogonality, i.e., any register pair can be used as long as the result and the two oper-

ands do not share register pairs. The routine is non-destructive to the operands.

mul16x16_32:

clr r2

mul r23, r21

movw r19:r18, r1:r0

mul r22, r20

movw r17:r16, r1:r0

; ah * bh

; al * bl

; ah * bl

mul

add

adc

mul

add

adc

ret

r23, r20

r17, r0

r18, r1

r19, r2

r21, r22

r17, r0

r18, r1

r19, r2

; bh * al

122

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.28.7.3

muls16x16_32

Description

Signed multiply of two 16-bit numbers with a 32-bit result.

Usage

R19:R18:R17:R16 = R23:R22 • R21:R20

Statistics

Cycles: 19 + ret

Words: 15 + ret

Register usage: R0 to R2 and R16 to R23 (11 registers)⁽¹⁾

Note: 1. The routine is non-destructive to the operands.

muls16x16_32:

clr r2

muls r23, r21

; (signed)ah * (signed)bh

movw r19:r18, r1:r0

mul

r22, r20

; al * bl

movw r17:r16, r1:r0

mulsu r23, r20

; (signed)ah * bl

; Sign extend

sbc

add

adc

r19, r2

r17, r0

r18, r1

r19, r2

mulsu r21, r22

; (signed)bh * al

; Sign Extend

sbc

add

adc

ret

r19, r2

r17, r0

r18, r1

r19, r2

123

1138H–FPSLI–6/05

4.28.7.4

mac16x16_32

Description

Signed multiply-accumulate of two 16-bit numbers with a 32-bit result.

Usage

R19:R18:R17:R16 += R23:R22 • R21:R20

Statistics

Cycles: 23 + ret

Words: 19 + ret

Register usage: R0 to R2 and R16 to R23 (11 registers)

mac16x16_32:

clr r2

; Register Usage Optimized

muls r23, r21

; (signed)ah * (signed)bh

add

adc

r18, r0

r19, r1

mul

add

adc

r22, r20

r16, r0

r17, r1

r18, r2

r19, r2

; al * bl

mulsu r23, r20

; (signed)ah * bl

sbc

add

adc

r19, r2

r17, r0

r18, r1

r19, r2

mulsu r21, r22

; (signed)bh * al

; Sign extend

sbc

add

adc

r19, r2

r17, r0

r18, r1

r19, r2

ret

mac16x16_32_method_B:

Size

; uses two temporary registers (r4,r5), Speed /

Optimized

; but reduces cycles/words by 1

clr

r2

muls r23, r21

; (signed)ah * (signed)bh

movw r5:r4,r1:r0

124

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

mul

r22, r20

; al * bl

add

adc

r16, r0

r17, r1

r18, r4

r19, r5

mulsu r23, r20

; (signed)ah * bl

; Sign extend

sbc

add

adc

r19, r2

r17, r0

r18, r1

r19, r2

mulsu r21, r22

; (signed)bh * al

; Sign extend

sbc

add

adc

r19, r2

r17, r0

r18, r1

r19, r2

ret

125

1138H–FPSLI–6/05

4.28.7.5

fmuls16x16_32

Description

Signed fractional multiply of two 16-bit numbers with a 32-bit result.

Usage

R19:R18:R17:R16 = (R23:R22 • R21:R20) << 1

Statistics

Cycles: 20 + ret

Words: 16 + ret

Register usage: R0 to R2 and R16 to R23 (11 registers)⁽¹⁾

Note:

1. The routine is non-destructive to the operands.

fmuls16x16_32:

clr

r2

fmuls r23, r21

; ( (signed)ah * (signed)bh ) << 1

; ( al * bl ) << 1

movw r19:r18, r1:r0

fmul r22, r20

adc

r18, r2

movw r17:r16, r1:r0

fmulsu

r23, r20

r19, r2

; ( (signed)ah * bl ) << 1

; Sign extend

sbc

add

r17, r0

r18, r1

r19, r2

adc

fmulsu

sbc

r21, r22

; ( (signed)bh * al ) << 1

; Sign extend

r19, r2

r17, r0

r18, r1

r19, r2

add

adc

ret

126

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.28.7.6

fmac16x16_32

Description

Signed fractional multiply-accumulate of two 16-bit numbers with a 32-bit result.

Usage

R19:R18:R17:R16 += (R23:R22 • R21:R20) << 1

Statistics

Cycles: 25 + ret

Words: 21 + ret

Register usage: R0 to R2 and R16 to R23 (11 registers)

fmac16x16_32:

clr r2

; Register usage optimized

fmuls r23, r21

; ( (signed)ah * (signed)bh ) << 1

add

adc

r18, r0

r19, r1

fmul r22, r20

; ( al * bl ) << 1

adc

add

adc

r18, r2

r19, r2

r16, r0

r17, r1

r18, r2

r19, r2

fmulsu

sbc

r23, r20

; ( (signed)ah * bl ) << 1

r19, r2

r17, r0

r18, r1

r19, r2

add

adc

fmulsu

sbc

r21, r22

; ( (signed)bh * al ) << 1

r19, r2

r17, r0

r18, r1

r19, r2

add

adc

ret

fmac16x16_32_method_B

speed/Size

; uses two temporary registers (r4,r5),

optimized

; but reduces cycles/words by 2

clr

r2

127

1138H–FPSLI–6/05

fmuls r23, r21

movw r5:r4,r1:r0

fmul r22, r20

; ( (signed)ah * (signed)bh ) << 1

; ( al * bl ) << 1

adc

r4, r2

add

r16, r0

adc

r17, r1

r18, r4

r19, r5

r23, r20

r19, r2

r17, r0

r18, r1

r19, r2

fmulsu

sbc

; ( (signed)ah * bl ) << 1

add

adc

fmulsu

r21, r22

; ( (signed)bh * al ) << 1

sbc

add

adc

r19, r2

r17, r0

r18, r1

r19, r2

ret

4.28.7.7

Comment on Implementations

All 16-bit x 16-bit = 32-bit functions implemented here start by clearing the R2 register, which is

just used as a “dummy” register with the “add with carry” (ADC) and “subtract with carry” (SBC)

operations. These operations do not alter the contents of the R2 register. If the R2 register is not

used elsewhere in the code, it is not necessary to clear the R2 register each time these functions

are called, but only once prior to the first call to one of the functions.

128

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.29 UARTs

The FPSLIC features two full duplex (separate receive and transmit registers) Universal Asyn-

chronous Receiver and Transmitter (UART). The main features are:

• Baud-rate Generator Generates any Baud-rate

• High Baud-rates at Low XTAL Frequencies

• 8 or 9 Bits Data

• Noise Filtering

• Overrun Detection

• Framing Error Detection

• False Start Bit Detection

• Three Separate Interrupts on TX Complete, TX Data Register Empty and RX Complete

• Multi-processor Communication Mode

• Double Speed UART Mode

4.29.1

Data Transmission

A block schematic of the UART transmitter is shown in Figure 4-41. The two UARTs are identical

and the functionality is described in general for the two UARTs.

Figure 4-41. UART Transmitter⁽¹⁾

DATA BUS

BAUD x 16

UART I/O DATA

REGISTER (UDRn)

BAUD RATE

GENERATOR

/16

XTAL

STORE UDRn

SHIFT ENABLE

PIN CONTROL

LOGIC

TXDn

BAUD

10(11)-BIT TX

SHIFT REGISTER

PE0/

PE2

CONTROL LOGIC

IDLE

UART CONTROL AND

STATUS REGISTER

(UCSRnB)

UART CONTROL AND

STATUS REGISTER

(UCSRnA)

DATA BUS

TXCn

IRQ

UDREn

IRQ

Note:

1. n = 0, 1

129

1138H–FPSLI–6/05

Data transmission is initiated by writing the data to be transmitted to the UART I/O Data Regis-

ter, UDRn. Data is transferred from UDRn to the Transmit shift register when:

• A new character has been written to UDRn after the stop bit from the previous character has

been shifted out. The shift register is loaded immediately.

• A new character has been written to UDRn before the stop bit from the previous character

has been shifted out. The shift register is loaded when the stop bit of the character currently

being transmitted has been shifted out.

If the 10(11)-bit Transmitter shift register is empty, data is transferred from UDRn to the shift reg-

ister. At this time the UDREn (UART Data Register Empty) bit in the UART Control and Status

Register, UCSRnA, is set. When this bit is set (one), the UART is ready to receive the next char-

acter. At the same time as the data is transferred from UDRn to the 10(11)-bit shift register, bit 0

of the shift register is cleared (start bit) and bit 9 or 10 is set (stop bit). If a 9-bit data word is

selected (the CHR9n bit in the UART Control and Status Register, UCSRnB is set), the TXB8 bit

in UCSRnB is transferred to bit 9 in the Transmit shift register.

On the Baud-rate clock following the transfer operation to the shift register, the start bit is shifted

out on the TXDn pin. Then follows the data, LSB first. When the stop bit has been shifted out,

the shift register is loaded if any new data has been written to the UDRn during the transmission.

During loading, UDREn is set. If there is no new data in the UDRn register to send when the stop

bit is shifted out, the UDREn flag will remain set until UDRn is written again. When no new data

has been written, and the stop bit has been present on TXDn for one bit length, the TX Complete

flag, TXCn, in UCSRnA is set.

The TXENn bit in UCSRnB enables the UART transmitter when set (one). When this bit is

cleared (zero), the PE0 (UART0) or PE2 (UART1) pin can be used for general I/O. When TXENn

is set, the UART Transmitter will be connected to PE0 (UART0) or PE2 (UART1), which is

forced to be an output pin regardless of the setting of the DDE0 bit in DDRE (UART0) or DDE2

in DDRE (UART1).

130

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.29.2

Data Reception

Figure 4-42 shows a block diagram of the UART Receiver.

Figure 4-42. UART Receiver⁽¹⁾

DATA BUS

UART I/O DATA

REGISTER (UDRn)

BAUD x 16

BAUD

BAUD RATE

XTAL

/16

GENERATOR

STORE UDRn

PIN CONTROL

LOGIC

RXDn

10(11)-BIT RX

SHIFT REGISTER

PE1/

PE3

DATA RECOVERY

LOGIC

UART CONTROL AND

STATUS REGISTER

(UCSRnB)

UART CONTROL AND

STATUS REGISTER

(UCSRnA)

DATA BUS

RXCn

IRQ

Note:

1. n = 0, 1

The receiver front-end logic samples the signal on the RXDn pin at a frequency 16 times the

baud-rate. While the line is idle, one single sample of logic 0 will be interpreted as the falling

edge of a start bit, and the start bit detection sequence is initiated. Let sample 1 denote the first

zero-sample. Following the 1-to-0 transition, the receiver samples the RXDn pin at samples 8, 9

and 10. If two or more of these three samples are found to be logic 1s, the start bit is rejected as

a noise spike and the receiver starts looking for the next 1-to-0 transition.

131

1138H–FPSLI–6/05

If however, a valid start bit is detected, sampling of the data bits following the start bit is per-

formed. These bits are also sampled at samples 8, 9 and 10. The logical value found in at least

two of the three samples is taken as the bit value. All bits are shifted into the transmitter shift reg-

ister as they are sampled. Sampling of an incoming character is shown in Figure 4-43. Note that

the description above is not valid when the UART transmission speed is doubled. See “Double

Speed Transmission” on page 138 for a detailed description.

Figure 4-43. Sampling Received Data⁽¹⁾

Note:

1. This figure is not valid when the UART speed is doubled. See “Double Speed Transmis-

sion” on page 138 for a detailed description.

When the stop bit enters the receiver, the majority of the three samples must be one to accept

the stop bit. If two or more samples are logic 0s, the Framing Error (FEn) flag in the UART Con-

trol and Status Register (UCSRnA) is set. Before reading the UDRn register, the user should

always check the FEn bit to detect Framing Errors.

Whether or not a valid stop bit is detected at the end of a character reception cycle, the data is

transferred to UDRn and the RXCn flag in UCSRnA is set. UDRn is in fact two physically sepa-

rate registers, one for transmitted data and one for received data. When UDRn is read, the

Receive Data register is accessed, and when UDRn is written, the Transmit Data register is

accessed. If the 9-bit data word is selected (the CHR9n bit in the UART Control and Status Reg-

ister, UCSRnB is set), the RXB8n bit in UCSRnB is loaded with bit 9 in the Transmit shift register

when data is transferred to UDRn.

If, after having received a character, the UDRn register has not been read since the last receive,

the OverRun (ORn) flag in UCSRnB is set. This means that the last data byte shifted into to the

shift register could not be transferred to UDRn and has been lost. The ORn bit is buffered, and is

updated when the valid data byte in UDRn is read. Thus, the user should always check the ORn

bit after reading the UDRn register in order to detect any overruns if the baud-rate is High or

CPU load is High.

When the RXEN bit in the UCSRnB register is cleared (zero), the receiver is disabled. This

means that the PE1 (n=0) or PE3 (n=1) pin can be used as a general I/O pin. When RXEN_nis

set, the UART Receiver will be connected to PE1 (UART0) or PE3 (UART1), which is forced to

be an input pin regardless of the setting of the DDE1 in DDRE (UART0) or DDB2 bit in DDRB

(UART1). When PE1 (UART0) or PE3 (UART1) is forced to input by the UART, the PORTE1

(UART0) or PORTE3 (UART1) bit can still be used to control the pull-up resistor on the pin.

When the CHR9n bit in the UCSRnB register is set, transmitted and received characters are 9

bits long plus start and stop bits. The 9th data bit to be transmitted is the TXB8n bit in UCSRnB

register. This bit must be set to the wanted value before a transmission is initiated by writing to

the UDRn register. The 9th data bit received is the RXB8n bit in the UCSRnB register.

132

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.29.3

Multi-processor Communication Mode

The Multi-processor Communication Mode enables several Slave MCUs to receive data from a

Master MCU. This is done by first decoding an address byte to find out which MCU has been

addressed. If a particular Slave MCU has been addressed, it will receive the following data bytes

as normal, while the other Slave MCUs will ignore the data bytes until another address byte is

received.

For an MCU to act as a Master MCU, it should enter 9-bit transmission mode (CHR9n in UCS-

RnB set). The 9-bit must be one to indicate that an address byte is being transmitted, and zero

to indicate that a data byte is being transmitted.

For the Slave MCUs, the mechanism appears slightly different for 8-bit and 9-bit Reception

mode. In 8-bit Reception mode (CHR9n in UCSRnB cleared), the stop bit is one for an address

byte and zero for a data byte. In 9-bit Reception mode (CHR9n in UCSRnB set), the 9-bit is one

for an address byte and zero for a data byte, whereas the stop bit is always High.

The following procedure should be used to exchange data in Multi-processor Communication

mode:

1. All Slave MCUs are in Multi-processor Communication Mode (MPCMn in UCSRnA is

set).

2. The Master MCU sends an address byte, and all Slaves receive and read this byte.

In the Slave MCUs, the RXCn flag in UCSRnA will be set as normal.

3. Each Slave MCU reads the UDRn register and determines if it has been selected. If

so, it clears the MPCMn bit in UCSRnA, otherwise it waits for the next address byte.

4. For each received data byte, the receiving MCU will set the receive complete flag

(RXCn in UCSRnA. In 8-bit mode, the receiving MCU will also generate a framing

error (FEn in UCSRnA set), since the stop bit is zero. The other Slave MCUs, which

still have the MPCMn bit set, will ignore the data byte. In this case, the UDRn register

and the RXCn, FEn, or flags will not be affected.

5. After the last byte has been transferred, the process repeats from step 2.

4.29.4

UART Control

UART0 I/O Data Register – UDR0

Bit

7

6

5

4

3

2

1

0

$0C ($2C)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

UDR0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

UART1 I/O Data Register – UDR1

Bit

7

6

5

4

3

2

1

0

$03 ($23)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

UDR1

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

The UDRn register is actually two physically separate registers sharing the same I/O address.

When writing to the register, the UART Transmit Data register is written. When reading from

UDRn, the UART Receive Data register is read.

133

1138H–FPSLI–6/05

UART0 Control and Status Registers – UCSR0A

Bit

7

6

5

4

3

2

-

1

0

$0B ($2B)

Read/Write

Initial Value

RXC0

TXC0

R/W

0

UDRE0

FE0

R

OR0

R

U2X0

R/W

0

MPCM0

R/W

0

UCSR0A

R

0

R

1

R

0

UART1 Control and Status Registers – UCSR1A

Bit

7

6

5

4

3

2

-

1

0

$02 ($22)

Read/Write

Initial Value

RXC1

TXC1

R/W

0

UDRE1

FE1

R

OR1

R

U2X1

R/W

0

MPCM1

R/W

0

UCSR1A

R

0

R

1

R

0

• Bit 7 - RXC0/RXC1: UART Receive Complete

This bit is set (one) when a received character is transferred from the Receiver Shift register to

UDRn. The bit is set regardless of any detected framing errors. When the RXCIEn bit in UCS-

RnB is set, the UART Receive Complete interrupt will be executed when RXCn is set (one).

RXCn is cleared by reading UDRn. When interrupt-driven data reception is used, the UART

Receive Complete Interrupt routine must read UDRn in order to clear RXCn, otherwise a new

interrupt will occur once the interrupt routine terminates.

• Bit 6 - TXC0/TXC1: UART Transmit Complete

This bit is set (one) when the entire character (including the stop bit) in the Transmit Shift regis-

ter has been shifted out and no new data has been written to UDRn. This flag is especially useful

in half-duplex communications interfaces, where a transmitting application must enter receive

mode and free the communications bus immediately after completing the transmission.

When the TXCIEn bit in UCSRnB is set, setting of TXCn causes the UART Transmit Complete

interrupt to be executed. TXCn is cleared by the hardware when executing the corresponding

interrupt handling vector. Alternatively, the TXCn bit is cleared (zero) by writing a logic 1 to the

bit.

• Bit 5 - UDRE0/UDRE1: UART Data Register Empty

This bit is set (one) when a character written to UDRn is transferred to the Transmit shift register.

Setting of this bit indicates that the transmitter is ready to receive a new character for

transmission.

When the UDRIEn bit in UCSRnB is set, the UART Transmit Complete interrupt will be executed

as long as UDREn is set and the global interrupt enable bit in SREG is set. UDREn is cleared by

writing UDRn. When interrupt-driven data transmittal is used, the UART Data Register Empty

Interrupt routine must write UDRn in order to clear UDREn, otherwise a new interrupt will occur

once the interrupt routine terminates.

UDREn is set (one) during reset to indicate that the transmitter is ready.

• Bit 4 - FE0/FE1: Framing Error

This bit is set if a Framing Error condition is detected, i.e., when the stop bit of an incoming char-

acter is zero.

The FEn bit is cleared when the stop bit of received data is one.

• Bit 3 - OR0/OR1: OverRun

134

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

This bit is set if an Overrun condition is detected, i.e., when a character already present in the

UDRn register is not read before the next character has been shifted into the Receiver Shift reg-

ister. The ORn bit is buffered, which means that it will be set once the valid data still in UDRn is

read.

The ORn bit is cleared (zero) when data is received and transferred to UDRn.

• Bit 2 - Res: Reserved Bit

This bit is reserved in the AT94K and will always read as zero.

• Bits 1 - U2X0/U2X1: Double the UART Transmission Speed

When this bit is set (one) the UART speed will be doubled. This means that a bit will be transmit-

ted/received in eight CPU clock periods instead of 16 CPU clock periods. For a detailed

description, see “Double Speed Transmission” on page 138”.

• Bit 0 - MPCM0/MPCM1: Multi-processor Communication Mode

This bit is used to enter Multi-processor Communication Mode. The bit is set when the Slave

MCU waits for an address byte to be received. When the MCU has been addressed, the MCU

switches off the MPCMn bit, and starts data reception.

For a detailed description, see “Multi-processor Communication Mode” on page 133.

UART0 Control and Status Registers – UCSR0B

Bit

7

6

5

4

3

2

1

0

$0A ($2A)

Read/Write

Initial Value

RXCIE0

R/W

0

TXCIE0

R/W

0

UDRIE0

R/W

0

RXEN0

R/W

0

TXEN0

R/W

0

CHR90

R/W

0

RXB80

TXB80

R/W

0

UCSR0B

R

1

UART1 Control and Status Registers – UCSR1B

Bit

7

6

5

4

3

2

1

0

$01 ($21)

Read/Write

Initial Value

RXCIE1

R/W

0

TXCIE1

R/W

0

UDRIE1

R/W

0

RXEN1

R/W

0

TXEN1

R/W

0

CHR91

R/W

0

RXB81

TXB81

R/W

0

UCSR1B

R

1

• Bit 7 - RXCIE0/RXCIE1: RX Complete Interrupt Enable

When this bit is set (one), a setting of the RXCn bit in UCSRnA will cause the Receive Complete

interrupt routine to be executed provided that global interrupts are enabled.

• Bit 6 - TXCIE0/TXCIE1: TX Complete Interrupt Enable

When this bit is set (one), a setting of the TXCn bit in UCSRnA will cause the Transmit Complete

interrupt routine to be executed provided that global interrupts are enabled.

• Bit 5 - UDRIE0/UDREI1: UART Data Register Empty Interrupt Enable

When this bit is set (one), a setting of the UDREn bit in UCSRnA will cause the UART Data Reg-

ister Empty interrupt routine to be executed provided that global interrupts are enabled.

• Bit 4 - RXEN0/RXEN1: Receiver Enable

This bit enables the UART receiver when set (one). When the receiver is disabled, the TXCn,

ORn and FEn status flags cannot become set. If these flags are set, turning off RXENn does not

cause them to be cleared.

135

1138H–FPSLI–6/05

• Bit 3 - TXEN0/TXEN1: Transmitter Enable

This bit enables the UART transmitter when set (one). When disabling the transmitter while

transmitting a character, the transmitter is not disabled before the character in the shift register

plus any following character in UDRn has been completely transmitted.

• Bit 2 - CHR90/CHR91: 9-bit Characters

When this bit is set (one) transmitted and received characters are 9-bit long plus start and stop

bits. The 9-bit is read and written by using the RXB8n and TXB8n bits in UCSRnB, respectively.

The 9th data bit can be used as an extra stop bit or a parity bit.

• Bit 1 - RXB80/RXB81: Receive Data Bit 8

When CHR9n is set (one), RXB8n is the 9th data bit of the received character.

• Bit 0 - TXB80/TXB81: Transmit Data Bit 8

When CHR9n is set (one), TXB8n is the 9th data bit in the character to be transmitted.

4.29.5

Baud-rate Generator

The baud-rate generator is a frequency divider which generates baud-rates according to the fol-

lowing equation⁽¹⁾:

f

CK

BAUD = ---------------------------------

16(UBR + 1)

• BAUD = Baud-rate

• f_CK= Crystal Clock Frequency

• UBR = Contents of the UBRRHI and UBRRn Registers, (0 - 4095)

Note:

1. This equation is not valid when the UART transmission speed is doubled. See “Double Speed

Transmission” on page 138 for a detailed description.

For standard crystal frequencies, the most commonly used baud-rates can be generated by

using the UBR settings in Table 2. UBR values which yield an actual baud-rate differing less

than 2% from the target baud-rate, are bold in the table. However, using baud-rates that have

more than 1% error is not recommended. High error ratings give less noise resistance.

136

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 2. UBR Settings at Various Crystal Frequencies

Clock UBRRHI

MHz 7:4 or 3:0 UBRRn

UBR

HEX UBR

019

00C

006

003

002

001

Actual

Freq

Desired

Freq.

%

Clock

UBRRHI

7:4 or 3:0 UBRRn

UBR

HEX

02F

017

00B

007

005

003

002

001

000

Actual

Freq

Desired

Freq.

%

Error

Error MHz

UBR

1 0000

0000

00011001

00001100

00000110

00000011

00000010

00000001

00000000

25

12

6

3

2

1

0

2404

4808

8929

2400

4800

9600

14400

19200

28880

38400 22.9

57600 7.8

0.2 1.8432 0000

00101111

00010111

00001011

00000111

00000101

00000011

00000010

00000001

00000000

47

23

11

7

5

3

2

1

0

2400

4800

9600

2400

4800

9600

14400

19200

28880

38400

57600

0.0

0.2

7.5

7.8

7.6

0000

0.0

0.3

0.0

15625

20833

31250

62500

14400

19200

28800

38400

57600

115200

000

76800 22.9

115200 84.3

76800 33.3

115200 0.0

0

Clock UBRRHI

MHz 7:4 or 3:0 UBRRn

9.216 0000

UBR

HEX UBR

Actual

Freq

Desired

Freq.

%

Clock

UBRRHI

7:4 or 3:0 UBRRn

UBR

HEX

1DF

0EF

077

04F

03B

027

01D

013

00E

009

004

001

000

Actual

Freq

Desired

Freq.

%

Error

0.0

Error MHz

UBR

11101111

01110111

00111011

00100111

00011101

00010011

00001110

00001001

00000111

00000100

00000001

00000000

0EF

077

03B

027

01D

013

00E

009

007

004

001

000

239

119

59

39

29

19

14

9

7

4

1

0

2400

4800

9600

2400

4800

9600

14400

19200

28880

38400

57600

76800

115200

0.0 18.432 0001

11011111

11101111

01110111

01001111

00111011

00100111

00011101

00010011

00001110

00001001

00000100

00000001

00000000

479

239

119

79

59

39

29

19

14

9

2400

4800

9600

2400

4800

9600

0000

0.0

0.3

0.0

6.7

0.0

0000

0.0

0.3

0.0

14400

19200

28800

38400

57600

72000

115200

288000

576000

14400

19200

28800

38400

57600

76800

115200

230400

576000

14400

19200

28880

38400

57600

76800

115200

230400

230400 20.0

460800 20.0

912600 58.4

4

1

0

460800 20.0

912600 20.8

0

1152000

Clock UBRRHI

MHz 7:4 or 3:0 UBRRn

UBR

HEX UBR

Actual

Freq

Desired

Freq.

%

Clock

UBRRHI

7:4 or 3:0 UBRRn

40 0100

UBR

HEX

411

208

103

0AC

081

056

040

02A

020

015

00A

004

002

Actual

Freq

Desired

Freq.

%

Error

Error MHz

0.0

UBR

25.576 0010

0001

10011001

01001100

10100110

01101110

01010010

00110110

00101001

00011011

00010100

00001101

00000110

00000011

00000001

299

14C

0A6

06E

052

036

029

01B

014

00D

006

003

001

665

2400

4800

9572

2400

4800

9600

00010001

00001000

00000011

10101100

10000001

01010110

01000000

00101010

00100000

00010101

00001010

00000100

00000010

1041

520

259

172

129

86

2399

4798

9615

2400

4800

9600

0.0

332

166

110

82

54

41

27

20

13

6

0.0

0.3

0.0

0.3

0.6

0.9

0010

0001

0000

0.0

0.2

0.4

0.2

0.5

0.2

0.9

1.4

7.8

9.5

0000

14401

19259

29064

38060

57089

76119

114179

228357

399625

799250

14400

19200

28880

38400

57600

76800

115200

230400

14451

19231

28736

38462

58140

75758

113636

227273

500000

833333

14400

19200

28880

38400

57600

76800

115200

230400

460800

912600

0000

64

42

32

21

10

4

2

0000

0.9

0000

3

1

460800 15.3

912600 14.2

UART0 and UART1 High Byte Baud-rate Register UBRRHI

Bit

7

6

5

4

3

2

1

0

$20 ($40)

Read/Write

Initial Value

MSB1

R/W

0

LSB1

R/W

0

MSB0

R/W

0

LSB0

R/W

0

UBRRHI

R/W

0

R/W

0

R/W

0

R/W

0

The UART baud register is a 12-bit register. The 4 most significant bits are located in a separate

register, UBRRHI. Note that both UART0 and UART1 share this register. Bit 7 to bit 4 of

UBRRHI contain the 4 most significant bits of the UART1 baud register. Bit 3 to bit 0 contain the

4 most significant bits of the UART0 baud register.

137

1138H–FPSLI–6/05

UART0 Baud-rate Register Low Byte – UBRR0

Bit

7

6

5

4

3

2

1

0

$09 ($29)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

UBRR0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

UART1 Baud-rate Register Low Byte – UBRR1

Bit

7

6

5

4

3

2

1

0

$00 ($20)

Read/Write

Initial Value

MSB

R/W

0

LSB

R/W

0

UBRR1

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

R/W

0

UBRRn stores the 8 least significant bits of the UART baud-rate register.

4.29.6

Double Speed Transmission

The FPSLIC provides a separate UART mode that allows the user to double the communication

speed. By setting the U2X bit in UART Control and Status Register UCSRnA, the UART speed

will be doubled. The data reception will differ slightly from normal mode. Since the speed is dou-

bled, the receiver front-end logic samples the signals on the RXDn pin at a frequency 8 times the

baud-rate. While the line is idle, one single sample of logic 0 will be interpreted as the falling

edge of a start bit, and the start bit detection sequence is initiated. Let sample 1 denote the first

zero-sample. Following the 1-to-0 transition, the receiver samples the RXDn pin at samples 4, 5

and 6. If two or more of these three samples are found to be logic 1s, the start bit is rejected as

a noise spike and the receiver starts looking for the next 1-to-0 transition.

If however, a valid start bit is detected, sampling of the data bits following the start bit is per-

formed. These bits are also sampled at samples 4, 5 and 6. The logical value found in at least

two of the three samples is taken as the bit value. All bits are shifted into the transmitter shift reg-

ister as they are sampled. Sampling of an incoming character is shown in Figure 4-44.

Figure 4-44. Sampling Received Data when the Transmission Speed is Doubled

RXD

START BIT

D0

D1

D2

D3

D4

D5

D6

D7

STOP BIT

RECEIVER

SAMPLING

4.29.7

The Baud-rate Generator in Double UART Speed Mode

Note that the baud-rate equation is different from the equation⁽¹⁾at page 136 when the UART

speed is doubled:

f

CK

BAUD = ------------------------------

8(UBR + 1)

• BAUD = Baud-rate

• f_CK= Crystal Clock Frequency

• UBR = Contents of the UBRRHI and UBRRn Registers, (0 - 4095)

Note:

1. This equation is only valid when the UART transmission speed is doubled.

For standard crystal frequencies, the most commonly used baud-rates can be generated by

using the UBR settings in Table 2. UBR values which yield an actual baud-rate differing less

than 1.5% from the target baud-rate, are bold in the table. However since the number of samples

138

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

are reduced and the system clock might have some variance (this applies especially when using

resonators), it is recommended that the baud-rate error is less than 0.5%. See Table 3 for the

UBR settings at various crystal frequencies in double UART speed mode.

Table 3. UBR Settings at Various Crystal Frequencies in Double UART Speed Mode

Clock UBRRHI

UBR

Actual Desired

%

Clock UBRRHI

UBR

Actual Desired

%

MHz 7:4 or 3:0 UBRRn HEX UBR

Freq

2404

4808

Freq. Error MHz 7:4 or 3:0 UBRRn

HEX UBR

Freq

2400

4800

Freq. Error

1

1.843

0000

00110011 033 51

00011001 019 25

00001100 00C 12

2400

4800

9600

0.2

0000

01011111 05F

95

47

23

15

2400

4800

9600

0.0

00101111 02F

00010111 017

00001111 00F

9615

9600

00001000 008

00000110 006

00000011 003

00000010 002

00000001 001

00000000 000

8

6

3

2

1

0

13889

17857

31250

41667

62500

14400 3.7

19200 7.5

28880 7.6

38400 7.8

57600 7.8

76800 22.9

14400

19200

28800

38400

57600

76800

14400 0.0

19200 0.0

28880 0.3

38400 0.0

57600 0.0

76800 0.0

00001011 00B 11

00000111 007

00000101 005

00000011 003

00000010 002

00000001 001

7

5

3

2

1

125000 115200 7.8

115200 115200 0.0

Clock UBRRHI

UBR

Actual Desired

%

Clock UBRRHI

UBR

Actual Desired

%

MHz 7:4 or 3:0 UBRRn HEX UBR

Freq

2400

4800

Freq. Error MHz 7:4 or 3:0 UBRRn

HEX UBR

10111111 3BF 959

11011111 1DF 479

11101111 0EF 239

10011111 09F 159

01110111 077 119

Freq

2400

4800

Freq. Error

9.216

18.43

0001

0000

11011111 1DF 479

11101111 0EF 239

01110111 077 119

01001111 04F 79

00111011 03B 59

00100111 027 39

00011101 01D 29

00010011 013 19

00001110 00E 14

2400

4800

9600

14400 0.0

19200 0.0

28880 0.3

38400 0.0

57600 0.0

76800 0.0

0.0

0011

0001

0000

2400

4800

9600

0.0

9600

14400

19200

28800

38400

57600

76800

115200 115200 0.0

230400 230400 0.0

384000 460800 20.0

1152000 912600 20.8

14400

19200

28800

38400

57600

76800

115200 115200 0.0

230400 230400 0.0

460800 460800 0.0

14400 0.0

19200 0.0

28880 0.3

38400 0.0

57600 0.0

76800 0.0

01001111 04F

00111011 03B 59

00100111 027 39

00011101 01D 29

00010011 013

00001001 009

00000100 004

00000010 002

79

00001001 009

00000100 004

00000010 002

00000000 000

9

4

2

0

19

9

4

2

912600 18.8

768000

Clock UBRRHI

UBR

Actual Desired

%

Clock UBRRHI

UBR

Actual Desired

%

MHz 7:4 or 3:0 UBRRn HEX UBR

Freq

2400

4800

Freq. Error MHz 7:4 or 3:0 UBRRn

HEX UBR

00100010 822 2082

00010001 411 1041

00001000 208 520

01011010 15A 346

00000011 103 259

10101100 0AC 172

10000001 081 129

Freq

2400

4798

Freq. Error

25.576

40

0101

0010

0001

0000

00110011 533 1331

10011001 299 665

01001110 14E 334

11011101 0DD 221

10100110 0A6 166

01101110 06E 110

01010010 052 82

00110111 037 55

00101001 029 41

00011011 01B 27

00001101 00D 13

2400

4800

9600

14400 0.0

19200 0.3

28880 0.3

38400 0.3

57600 0.9

76800 0.9

0.0

0.6

1000

0100

0010

0001

0000

2400

4800

9600

0.0

9543

9597

14401

19144

28802

38518

57089

76119

114179 115200 0.9

228357 230400 0.9

456714 460800 0.9

799250 912600 14.2

14409

19231

28902

38462

57471

76923

116279 115200 0.9

227273 230400 1.4

454545 460800 1.4

1000000 912600 8.7

14400 0.1

19200 0.2

28880 0.1

38400 0.2

57600 0.2

76800 0.2

01010110 056

01000000 040

00101010 02A

00010101 015

00001010 00A

00000100 004

86

64

42

21

10

4

00000110 006

00000011 003

6

3

139

1138H–FPSLI–6/05

4.30 2-wire Serial Interface (Byte Oriented)

The 2-wire Serial Bus is a bi-directional two-wire serial communication standard. It is designed

primarily for simple but efficient integrated circuit (IC) control. The system is comprised of two

lines, SCL (Serial Clock) and SDA (Serial Data) that carry information between the ICs con-

nected to them. Various communication configurations can be designed using this bus.

Figure 4-45 shows a typical 2-wire Serial Bus configuration. Any device connected to the bus

can be Master or Slave.

Figure 4-45. 2-wire Serial Bus Configuration

V_CC

Device 1

Device 2

Device 3

.......

Device n

R1

R2

SCL

SDA

The 2-wire Serial Interface provides a serial interface that meets the 2-wire Serial Bus specifica-

tion and supports Master/Slave and Transmitter/Receiver operation at up to 400 kHz bus clock

rate. The 2-wire Serial Interface has hardware support for the 7-bit addressing, but is easily

extended to 10-bit addressing format in software. When operating in 2-wire Serial mode, i.e.,

when TWEN is set, a glitch filter is enabled for the input signals from the pins SCL and SDA, and

the output from these pins are slew-rate controlled. The 2-wire Serial Interface is byte oriented.

The operation of the serial 2-wire Serial Bus is shown as a pulse diagram in Figure 4-46, includ-

ing the START and STOP conditions and generation of ACK signal by the bus receiver.

Figure 4-46. 2-wire Serial Bus Timing Diagram

ACKNOWLEDGE

FROM RECEIVER

STOP CONDITION

SDA

SCL

MSB

1

R/W

BIT

2

7

8

9

1

2

8

9

ACK

START

CONDITION

REPEATED START CONDITION

The block diagram of the 2-wire Serial Bus interface is shown in Figure 4-47.

140

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-47. Block diagram of the 2-wire Serial Bus Interface

ADDRESS REGISTER

AND

COMPARATOR

TWAR

INPUT

DATA SHIFT

REGISTER

SDA

ACK

OUTPUT

TWDR

START/STOP

AND SYNC

TIMING

AND

INPUT

SCL

OUTPUT

ARBITRATION

CONTROL

SERIAL CLOCK

GENERATOR

CONTROL

REGISTER

TWCR

STATUS

STATE MACHINE

AND

STATUS

REGISTER

STATUS DECODER

TWSR

The CPU interfaces with the 2-wire Serial Interface via the following five I/O registers: the 2-wire

Serial Bit-rate Register (TWBR), the 2-wire Serial Control Register (TWCR), the 2-wire Serial

Status Register (TWSR), the 2-wire Serial Data Register (TWDR), and the 2-wire Serial Address

Register (TWAR, used in Slave mode).

The 2-wire Serial Bit-rate Register – TWBR

Bit

7

6

5

4

3

2

1

0

$1C ($3C)

Read/Write

Initial Value

TWBR7

R/W

0

TWBR6

R/W

0

TWBR5

R/W

0

TWBR4

R/W

0

TWBR3

R/W

0

TWBR2

R/W

0

TWBR1

R/W

0

TWBR0

R/W

0

TWBR

141

1138H–FPSLI–6/05

• Bits 7..0 - 2-wire Serial Bit-rate Register

TWBR selects the division factor for the bit-rate generator. The bit-rate generator is a frequency

divider which generates the SCL clock frequency in the Master modes according to the following

equation:

f

CK

Bit-rate = -------------------------------------

16 + 2(TWBR)

• Bit-rate = SCL frequency

• f_CK= CPU Clock frequency

• TWBR = Contents of the 2-wire Serial Bit Rate Register

Both the receiver and the transmitter can stretch the Low period of the SCL line when waiting for

user response, thereby reducing the average bit rate.

The 2-wire Serial Control Register – TWCR

Bit

7

6

5

4

3

2

1

-

0

$36 ($56)

Read/Write

Initial Value

TWINT

R/W

0

TWEA

R/W

0

TWSTA

R/W

0

TWSTO

R/W

0

TWWC

TWEN

R/W

0

TWIE

R/W

0

TWCR

R

0

R

0

• Bit 7 - TWINT: 2-wire Serial Interrupt Flag

This bit is set by the hardware when the 2-wire Serial Interface has finished its current job and

expects application software response. If the I-bit in the SREG and TWIE in the TWCR register

are set (one), the MCU will jump to the interrupt vector at address $0046. While the TWINT flag

is set, the bus SCL clock line Low period is stretched. The TWINT flag must be cleared by soft-

ware by writing a logic 1 to it. Note that this flag is not automatically cleared by the hardware

when executing the interrupt routine. Also note that clearing this flag starts the operation of the

2-wire Serial Interface, so all accesses to the 2-wire Serial Address Register – TWAR, 2-wire

Serial Status Register – TWSR, and 2-wire Serial Data Register – TWDR must be complete

before clearing this flag.

• Bit 6 - TWEA: 2-wire Serial Enable Acknowledge Flag

TWEA flag controls the generation of the acknowledge pulse. If the TWEA bit is set, the ACK

pulse is generated on the 2-wire Serial Bus if the following conditions are met:

• The device’s own Slave address has been detected

• A general call has been received, while the TWGCE bit in the TWAR is set

• A data byte has been received in Master Receiver or Slave Receiver mode

By setting the TWEA bit Low the device can be virtually disconnected from the 2-wire Serial Bus

temporarily. Address recognition can then be resumed by setting the TWEA bit again.

• Bit 5 - TWSTA: 2-wire Serial Bus START Condition Flag

The TWSTA flag is set by the CPU when it desires to become a Master on the 2-wire Serial Bus.

The 2-wire serial hardware checks if the bus is available, and generates a Start condition on the

bus if the bus is free. However, if the bus is not free, the 2-wire Serial Interface waits until a

STOP condition is detected, and then generates a new Start condition to claim the bus Master

status.

142

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

• Bit 4 - TWSTO: 2-wire Serial Bus STOP Condition Flag

TWSTO is a stop condition flag. In Master mode, setting the TWSTO bit in the control register

will generate a STOP condition on the 2-wire Serial Bus. When the STOP condition is executed

on the bus, the TWSTO bit is cleared automatically. In Slave mode, setting the TWSTO bit can

be used to recover from an error condition. No stop condition is generated on the bus then, but

the 2-wire Serial Interface returns to a well-defined unaddressed Slave mode.

• Bit 3 - TWWC: 2-wire Serial Write Collision Flag

Set when attempting to write to the 2-wire Serial Data Register – TWDR when TWINT is Low.

This flag is updated at each attempt to write the TWDR register.

• Bit 2 - TWEN: 2-wire Serial Interface Enable Flag

The TWEN bit enables 2-wire serial operation. If this flag is cleared (zero), the bus outputs SDA

and SCL are set to high impedance state and the input signals are ignored. The interface is acti-

vated by setting this flag (one).

• Bit 1 - Res: Reserved Bit

This bit is reserved in the AT94K and will always read as zero.

• Bit 0 - TWIE: 2-wire Serial Interrupt Enable

When this bit is enabled and the I-bit in SREG is set, the 2-wire Serial Interrupt will be activated

for as long as the TWINT flag is High.

The TWCR is used to control the operation of the 2-wire Serial Interface. It is used to enable the

2-wire Serial Interface, to initiate a Master access, to generate a receiver acknowledge, to gen-

erate a stop condition, and control halting of the bus while the data to be written to the bus are

written to the TWDR. It also indicates a write collision if data is attempted written to TWDR while

the register is inaccessible.

The 2-wire Serial Status Register – TWSR

Bit

7

6

5

4

3

2

-

1

-

0

-

$1D ($3D)

Read/Write

Initial Value

TWS7

TWS6

TWS5

TWS4

TWS3

TWSR

R

1

R

1

R

1

R

1

R

1

R

0

R

0

R

0

• Bits 7..3 - TWS: 2-wire Serial Status

These 5 bits reflect the status of the 2-wire Serial Logic and the 2-wire Serial Bus.

• Bits 2..0 - Res: Reserved Bits

These bits are reserved in the AT94K and will always read as zero

TWSR is read only. It contains a status code which reflects the status of the 2-wire Serial Logic

and the 2-wire Serial Bus. There are 26 possible status codes. When TWSR contains $F8, no

relevant state information is available and no 2-wire Serial Interrupt is requested. A valid status

code is available in TWSR one CPU clock cycle after the 2-wire Serial Interrupt flag (TWINT) is

set by the hardware and is valid until one CPU clock cycle after TWINT is cleared by software.

Table 4-29 to Table 4-33 give the status information for the various modes.

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The 2-wire Serial Data Register – TWDR

Bit

7

6

5

4

3

2

1

0

$1F ($3F)

Read/Write

Initial Value

MSB

R/W

1

LSB

R/W

1

TWDR

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

• Bits 7..0 - TWD: 2-wire Serial Data Register

These eight bits constitute the next data byte to be transmitted, or the latest data byte received

on the 2-wire Serial Bus.

In transmit mode, TWDR contains the next byte to be transmitted. In receive mode, the TWDR

contains the last byte received. It is writable while the 2-wire Serial Interface is not in the process

of shifting a byte. This occurs when the 2-wire Serial Interrupt flag (TWINT) is set by the hard-

ware. Note that the data register cannot be initialized by the user before the first interrupt occurs.

The data in TWDR remains stable as long as TWINT is set. While data is shifted out, data on the

bus is simultaneously shifted in. TWDR always contains the last byte present on the bus, except

after a wake up from Power-down Mode, or Power-save Mode by the 2-wire Serial Interrupt. For

example, in the case of the lost bus arbitration, no data is lost in the transition from Master-to-

Slave. Receiving the ACK flag is controlled by the 2-wire Serial Logic automatically, the CPU

cannot access the ACK bit directly.

The 2-wire Serial (Slave) Address Register – TWAR

Bit

7

6

5

4

3

2

1

0

$1E ($3E)

Read/Write

Initial Value

MSB

R/W

1

LSB

R/W

1

TWGCE TWAR

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

0

• Bits 7..1 - TWA: 2-wire Serial Slave Address Register

These seven bits constitute the Slave address of the 2-wire Serial Bus interface unit.

• Bit 0 - TWGCE: 2-wire Serial General Call Recognition Enable Bit

This bit enables, if set, the recognition of the General Call given over the 2-wire Serial Bus.

The TWAR should be loaded with the 7-bit Slave address (in the seven most significant bits of

TWAR) to which the 2-wire Serial Interface will respond when programmed as a Slave transmit-

ter or receiver, and not needed in the Master modes. The LSB of TWAR is used to enable

recognition of the general call address ($00). There is an associated address comparator that

looks for the Slave address (or general call address if enabled) in the received serial address. If

a match is found, an interrupt request is generated.

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AT94KAL Series FPSLIC

4.30.1

2-wire Serial Modes

The 2-wire Serial Interface can operate in four different modes:

• Master Transmitter

• Master Receiver

• Slave Receiver

• Slave Transmitter

Data transfer in each mode of operation is shown in Figure 4-48 to Figure 4-51. These figures

contain the following abbreviations:

S: START condition

R: Read bit (High level at SDA)

W: Write bit (Low level at SDA)

A: Acknowledge bit (Low level at SDA)

A: Not acknowledge bit (High level at SDA)

Data: 8-bit data byte

P: STOP condition

In Figure 4-48 to Figure 4-51, circles are used to indicate that the 2-wire Serial Interrupt flag is

set. The numbers in the circles show the status code held in TWSR. At these points, an interrupt

routine must be executed to continue or complete the 2-wire Serial Transfer. The 2-wire Serial

Transfer is suspended until the 2-wire Serial Interrupt flag is cleared by software.

The 2-wire Serial Interrupt flag is not automatically cleared by the hardware when executing the

interrupt routine. Also note that the 2-wire Serial Interface starts execution as soon as this bit is

cleared, so that all access to TWAR, TWDR and TWSR must have been completed before clear-

ing this flag.

When the 2-wire Serial Interrupt flag is set, the status code in TWSR is used to determine the

appropriate software action. For each status code, the required software action and details of

the following serial transfer are given in Table 4-29 to Table 4-33.

4.30.1.1

Master Transmitter Mode

In the Master Transmitter mode, a number of data bytes are transmitter to a Slave Receiver, see

Figure 4-48. Before the Master Transmitter mode can be entered, the TWCR must be initialized

as shown in Table 4-26.

Table 4-26. TWCR: Master Transmitter Mode Initialization

TWCR

TWINT

TWEA

TWSTA

TWSTO

TWWC

TWEN

-

TWIE

value

0

X

0

1

0

X

TWEN must be set to enable the 2-wire Serial Interface, TWSTA and TWSTO must be cleared.

The Master Transmitter mode may now be entered by setting the TWSTA bit. The 2-wire Serial

Logic will now test the 2-wire Serial Bus and generate a START condition as soon as the bus

becomes free. When a START condition is transmitted, the 2-wire Serial Interrupt flag (TWINT)

is set by the hardware, and the status code in TWSR will be $08. TWDR must then be loaded

with the Slave address and the data direction bit (SLA+W). The TWINT flag must then be

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cleared by software before the 2-wire Serial Transfer can continue. The TWINT flag is cleared by

writing a logic 1 to the flag.

When the Slave address and the direction bit have been transmitted and an acknowledgment bit

has been received, TWINT is set again and a number of status codes in TWSR are possible.

Status codes $18, $20, or $38 apply to Master mode, and status codes $68, $78, or $B0 apply to

Slave mode. The appropriate action to be taken for each of these status codes is detailed in

Table 4-29. The data must be loaded when TWINT is High only. If not, the access will be dis-

carded, and the Write Collision bit, TWWC, will be set in the TWCR register. This scheme is

repeated until a STOP condition is transmitted by writing a logic 1 to the TWSTO bit in the

TWCR register.

After a repeated START condition (state $10) the 2-wire Serial Interface may switch to the Mas-

ter Receiver mode by loading TWDR with SLA+R.

4.30.1.2

Master Receiver Mode

In the Master Receiver mode, a number of data bytes are received from a Slave Transmitter,

see Figure 4-49. The transfer is initialized as in the Master Transmitter mode. When the START

condition has been transmitted, the TWINT flag is set by the hardware. The software must then

load TWDR with the 7-bit Slave address and the data direction bit (SLA+R). The 2-wire Serial

Interrupt flag must then be cleared by software before the 2-wire Serial Transfer can continue.

When the Slave address and the direction bit have been transmitted and an acknowledgment bit

has been received, TWINT is set again and a number of status codes in TWSR are possible.

Status codes $40, $48, or $38 apply to Master mode, and status codes $68, $78, or $B0 apply to

Slave mode. The appropriate action to be taken for each of these status codes is detailed in

Table 4-30. Received data can be read from the TWDR register when the TWINT flag is set High

by the hardware. This scheme is repeated until a STOP condition is transmitted by writing a logic

1 to the TWSTO bit in the TWCR register.

After a repeated START condition (state $10), the 2-wire Serial Interface may switch to the Mas-

ter Transmitter mode by loading TWDR with SLA+W.

4.30.1.3

Slave Receiver Mode

In the Slave Receiver mode, a number of data bytes are received from a Master Transmitter,

see Figure 4-50. To initiate the Slave Receiver mode, TWAR and TWCR must be initialized as

follows:

Table 4-27. TWAR: Slave Receiver Mode Initialization

TWAR

TWA6

TWA5

TWA4

TWA3

TWA2

TWA1

TWA0

TWGCE

value

Device’s own Slave address

The upper 7 bits are the address to which the 2-wire Serial Interface will respond when

addressed by a Master. If the LSB is set, the 2-wire Serial Interface will respond to the general

call address ($00), otherwise it will ignore the general call address.

Table 4-28. TWCR: Slave Receiver Mode Initialization

TWCR

TWINT

TWEA

TWSTA

TWSTO

TWWC

TWEN

-

TWIE

value

0

1

0

1

0

X

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TWEN must be set to enable the 2-wire Serial Interface. The TWEA bit must be set to enable the

acknowledgment of the device’s own Slave address or the general call address. TWSTA and

TWSTO must be cleared.

When TWAR and TWCR have been initialized, the 2-wire Serial Interface waits until it is

addressed by its own Slave address (or the general call address if enabled) followed by the data

direction bit which must be “0” (write) for the 2-wire Serial Interface to operate in the Slave

Receiver mode. After its own Slave address and the write bit have been received, the 2-wire

Serial Interrupt flag is set and a valid status code can be read from TWSR. The status code is

used to determine the appropriate software action. The appropriate action to be taken for each

status code is detailed in Table 4-31. The Slave Receiver mode may also be entered if arbitra-

tion is lost while the 2-wire Serial Interface is in the Master mode (see states $68 and $78).

If the TWEA bit is reset during a transfer, the 2-wire Serial Interface will return a “Not Acknowl-

edged” (1) to SDA after the next received data byte. While TWEA is reset, the 2-wire Serial

Interface does not respond to its own Slave address. However, the 2-wire Serial Bus is still mon-

itored and address recognition may resume at any time by setting TWEA. This implies that the

TWEA bit may be used to temporarily isolate the 2-wire Serial Interface from the 2-wire serial

bus.

In ADC Noise Reduction Mode, Power-down Mode and Power-save Mode, the clock system to

the 2-wire Serial Interface is turned off. If the Slave Receiver mode is enabled, the interface can

still acknowledge a general call and its own Slave address by using the 2-wire serial bus clock

as a clock source. The part will then wake up from sleep and the 2-wire Serial Interface will hold

the SCL clock Low during the wake up and until the TWCINT flag is cleared.

Note that the 2-wire Serial Data Register – TWDR does not reflect the last byte present on the

bus when waking up from these Sleep Modes.

4.30.1.4

Slave Transmitter Mode

In the Slave Transmitter mode, a number of data bytes are transmitted to a Master Receiver

(see Figure 4-51). The transfer is initialized as in the Slave Receiver mode. When TWAR and

TWCR have been initialized, the 2-wire Serial Interface waits until it is addressed by its own

Slave address (or the general call address if enabled) followed by the data direction bit which

must be “1” (read) for the 2-wire Serial Interface to operate in the Slave Transmitter mode. After

its own Slave address and the read bit have been received, the 2-wire Serial Interrupt flag is set

and a valid status code can be read from TWSR. The status code is used to determine the

appropriate software action. The appropriate action to be taken for each status code is detailed

in Table 4-32. The Slave Transmitter mode may also be entered if arbitration is lost while the 2-

wire Serial Interface is in the Master mode (see state $B0).

If the TWEA bit is reset during a transfer, the 2-wire Serial Interface will transmit the last byte of

the transfer and enter state $C0 or state $C8. the 2-wire Serial Interface is switched to the not

addressed Slave mode, and will ignore the Master if it continues the transfer. Thus the Master

Receiver receives all “1” as serial data. While TWEA is reset, the 2-wire Serial Interface does not

respond to its own Slave address. However, the 2-wire serial bus is still monitored and address

recognition may resume at any time by setting TWEA. This implies that the TWEA bit may be

used to temporarily isolate the 2-wire Serial Interface from the 2-wire serial bus.

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4.30.1.5

Miscellaneous States

There are two status codes that do not correspond to a defined 2-wire Serial Interface state: Sta-

tus $F8 and Status $00, see Table 4-33.

Status $F8 indicates that no relevant information is available because the 2-wire Serial Interrupt

flag (TWINT) is not set yet. This occurs between other states, and when the 2-wire Serial Inter-

face is not involved in a serial transfer.

Status $00 indicates that a bus error has occurred during a 2-wire serial transfer. A bus error

occurs when a START or STOP condition occurs at an illegal position in the format frame.

Examples of such illegal positions are during the serial transfer of an address byte, a data byte

or an acknowledge bit. When a bus error occurs, TWINT is set. To recover from a bus error, the

TWSTO flag must set and TWINT must be cleared by writing a logic 1 to it. This causes the 2-

wire Serial Interface to enter the not addressed Slave mode and to clear the TWSTO flag (no

other bits in TWCR are affected). The SDA and SCL lines are released and no STOP condition

is transmitted.

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Table 4-29. Status Codes for Master Transmitter Mode

Application Software Response

To TWCR

Status

Code

(TWSR)

Status of the 2-wire

Serial Bus and 2-wire

Serial Hardware

Next Action Taken by 2-wire

To/From TWDR

STA

STO

TWINT

TWEA

Serial Hardware

SLA+W will be transmitted;

A START condition

has been transmitted

$08

$10

Load SLA+W

X

0

1

X

ACK or NOT ACK will be received

SLA+W will be transmitted;

Load SLA+W or

Load SLA+R

X

0

1

X

A repeated START

condition has been

transmitted

ACK or NOT ACK will be received

SLA+R will be transmitted;

Logic will switch to Master Receiver mode

Data byte will be transmitted and ACK or NOT

ACK will be received

Load data byte or

0

1

X

Repeated START will be transmitted

SLA+W has been

transmitted;

ACK has been

received

No TWDR action or

1

0

1

X

STOP condition will be transmitted and

TWSTO flag will be reset

$18

$20

$28

STOP condition followed by a START

condition will be transmitted and TWSTO flag

will be reset

No TWDR action

Load data byte or

1

0

1

0

1

X

Data byte will be transmitted and ACK or NOT

ACK will be received

Repeated START will be transmitted

SLA+W has been

transmitted;

NOT ACK has been

received

No TWDR action or

1

0

1

X

STOP condition will be transmitted and

TWSTO flag will be reset

STOP condition followed by a START

condition will be transmitted and TWSTO flag

will be reset

No TWDR action

Load data byte or

1

0

1

0

1

X

Data byte will be transmitted and ACK or NOT

ACK will be received

Repeated START will be transmitted

Data byte has been

transmitted;

ACK has been

received

No TWDR action or

1

0

1

X

STOP condition will be transmitted and

TWSTO flag will be reset

STOP condition followed by a START

condition will be transmitted and TWSTO flag

will be reset

No TWDR action

Load data byte or

1

0

1

0

1

X

Data byte will be transmitted and ACK or NOT

ACK will be received

Repeated START will be transmitted

Data byte has been

transmitted;

NOT ACK has been

received

No TWDR action or

1

0

1

X

STOP condition will be transmitted and

TWSTO flag will be reset

$30

$38

STOP condition followed by a START

condition will be transmitted and TWSTO flag

will be reset

No TWDR action

1

X

2-wire serial bus will be released and not

addressed Slave mode entered

No TWDR action or

No TWDR action

0

1

0

1

X

Arbitration lost in

SLA+W or data bytes

A START condition will be transmitted when

the bus becomes free

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Figure 4-48. Formats and States in the Master Transmitter Mode

MT

Successfull

S

SLA

W

A

DATA

A

P

transmission

to a slave

receiver

$08

$18

$28

Next transfer

started with a

repeated start

condition

S

SLA

W

R

$10

Not acknowledge

received after the

slave address

A

P

$20

MR

Not acknowledge

received after a data

byte

A

P

$30

Arbitration lost in slave

address or data byte

Other master

continues

Other master

continues

A or A

$38

A

$38

Arbitration lost and

addressed as slave

Other master

continues

To corresponding

states in slave mode

$68 $78 $B0

Any number of data bytes

and their associated acknowledge bits

From master to slave

From slave to master

DATA

A

This number (contained in TWSR) corresponds

to a defined state of the 2-wire serial bus

n

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AT94KAL Series FPSLIC

Table 4-30. Status Codes for Master Receiver Mode

Application Software Response

To TWCR

Status

Code

(TWSR)

Status of the 2-wire

Serial Bus and 2-wire

Serial Hardware

Next Action Taken by 2-wire Serial

To/From TWDR

STA

STO

TWINT

TWEA

Hardware

SLA+R will be transmitted

A START condition has

been transmitted

$08

$10

Load SLA+R

X

0

1

X

ACK or NOT ACK will be received

SLA+R will be transmitted

Load SLA+R or

Load SLA+W

X

0

1

X

A repeated START

condition has been

transmitted

ACK or NOT ACK will be received

SLA+W will be transmitted

Logic will switch to Master Transmitter mode

2-wire serial bus will be released and not

addressed Slave mode will be entered

No TWDR action or

No TWDR action

No TWDR action or

No TWDR action

0

1

0

1

X

0

1

Arbitration lost in

SLA+R or NOT ACK bit

$38

$40

A START condition will be transmitted when

the bus becomes free

Data byte will be received and NOT ACK will

be returned

SLA+R has been

transmitted;

ACK has been received

Data byte will be received and ACK will be

returned

Repeated START will be transmitted

No TWDR action or

1

0

1

X

SLA+R has been

transmitted;

NOT ACK has been

received

STOP condition will be transmitted and

TWSTO flag will be reset

$48

$50

$58

STOP condition followed by a START

condition will be transmitted and TWSTO flag

will be reset

No TWDR action

1

X

Data byte will be received and NOT ACK will

be returned

Read data byte or

Read data byte

0

1

0

1

Data byte has been

received;

ACK has been returned

Data byte will be received and ACK will be

returned

Repeated START will be transmitted

Read data byte or

1

0

1

X

Data byte has been

received;

NOT ACK has been

returned

STOP condition will be transmitted and

TWSTO flag will be reset

STOP condition followed by a START

condition will be transmitted and TWSTO flag

will be reset

Read data byte

1

X

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Figure 4-49. Formats and States in the Master Receiver Mode

MR

Successfull

S

SLA

R

A

DATA

A

DATA

A

P

reception

from a slave

receiver

$08

$40

$50

$58

Next transfer

started with a

repeated start

condition

S

SLA

R

$10

Not acknowledge

received after the

slave address

W

A

P

$48

MT

Arbitration lost in slave

address or data byte

Other master

continues

Other master

continues

A or A

A

$38

A

$38

Arbitration lost and

addressed as slave

Other master

continues

To corresponding

states in slave mode

$68 $78 $B0

Any number of data bytes

and their associated acknowledge bits

From master to slave

From slave to master

DATA

A

This number (contained in TWSR) corresponds

to a defined state of the 2-wire serial bus

n

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AT94KAL Series FPSLIC

Table 4-31. Status Codes for Slave Receiver Mode

Application Software Response

To TWCR

Status

Code

(TWSR)

Status of the 2-wire

Serial Bus and 2-wire

Serial Hardware

Next Action Taken by 2-wire

To/From TWDR

No TWDR action or

No TWDR action

STA

X

STO

TWINT

TWEA

Serial Hardware

Data byte will be received and NOT ACK

will be returned

0

1

0

1

Own SLA+W has been

received;

ACK has been returned

$60

$68

$70

$78

$80

Data byte will be received and ACK will be

returned

X

Arbitration lost in

Data byte will be received and NOT ACK

will be returned

No TWDR action or

No TWDR action

X

0

1

0

1

SLA+R/W as Master;

own SLA+W has been

received;

Data byte will be received and ACK will be

returned

ACK has been returned

Data byte will be received and NOT ACK

will be returned

No TWDR action or

No TWDR action

X

0

1

0

1

General call address

has been received;

ACK has been returned

Data byte will be received and ACK will be

returned

Arbitration lost in

Data byte will be received and NOT ACK

will be returned

No TWDR action or

No TWDR action

X

0

1

0

1

SLA+R/W as Master;

General call address

has been received;

ACK has been returned

Data byte will be received and ACK will be

returned

Data byte will be received and NOT ACK

will be returned

Previously addressed

with own SLA+W; data

has been received;

No TWDR action or

No TWDR action

X

0

1

0

1

Data byte will be received and ACK will be

returned

ACK has been returned

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA

Read data byte or

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”

Previously addressed

with own SLA+W; data

has been received;

NOT ACK has been

returned

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA; a

START condition will be transmitted when

the bus becomes free

$88

Read data byte or

Read data byte

1

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”; a START condition

will be transmitted when the bus becomes

free

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Table 4-31. Status Codes for Slave Receiver Mode (Continued)

Application Software Response

Status

Code

(TWSR)

Status of the 2-wire

Serial Bus and 2-wire

Serial Hardware

To TWCR

Next Action Taken by 2-wire

Serial Hardware

To/From TWDR

Read data byte or

Read data byte

STA

X

STO

TWINT

TWEA

Data byte will be received and NOT ACK

will be returned

Previously addressed

with general call; data

has been received;

0

1

0

1

$90

Data byte will be received and ACK will be

returned

X

ACK has been returned

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA

Read data byte or

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”

Previously addressed

with general call; data

has been received;

NOT ACK has been

returned

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA; a

START condition will be transmitted when

the bus becomes free

$98

Read data byte or

Read data byte

1

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”; a START condition

will be transmitted when the bus becomes

free

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA

Read data byte or

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”

A STOP condition or

repeated START

condition has been

received while still

addressed as Slave

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA; a

START condition will be transmitted when

the bus becomes free

$A0

Read data byte or

Read data byte

1

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”; a START condition

will be transmitted when the bus becomes

free

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Figure 4-50. Formats and States in the Slave Receiver Mode

Reception of the own

S

SLA

W

A

DATA

A

DATA

A

P or S

slave address and one or

more data bytes. All are

acknowledged

$60

$80

$A0

A

Last data byte received

is not acknowledged

P or S

$88

Arbitration lost as master

and addressed as slave

A

$68

A

Reception of the general call

address and one or more data

bytes

General Call

DATA

A

DATA

A

P or S

$70

$90

$A0

A

Last data byte received is

not acknowledged

P or S

$98

Arbitration lost as master and

addressed as slave by general call

A

$78

Any number of data bytes

and their associated acknowledge bits

From master to slave

From slave to master

DATA

A

This number (contained in TWSR) corresponds

to a defined state of the 2-wire serial bus

n

155

1138H–FPSLI–6/05

Table 4-32. Status Codes for Slave Transmitter Mode

Application Software Response

To TWCR

Status

Code

(TWSR)

Status of the 2-wire

Serial Bus and 2-wire

Serial Hardware

Next Action Taken by 2-wire

Serial Hardware

To/From TWDR

Load data byte or

Load data byte

STA

X

STO

TWINT

TWEA

Last data byte will be transmitted and NOT

ACK should be received

0

1

0

1

Own SLA+R has been

received;

ACK has been returned

$A8

$B0

$B8

Data byte will be transmitted and ACK should

be received

X

Arbitration lost in

Last data byte will be transmitted and NOT

ACK should be received

Load data byte or

Load data byte

X

0

1

0

1

SLA+R/W as Master;

own SLA+R has been

received;

Data byte will be transmitted and ACK should

be received

ACK has been returned

Last data byte will be transmitted and NOT

ACK should be received

Load data byte or

Load data byte

X

0

1

0

1

Data byte in TWDR has

been transmitted;

ACK has been received

Data byte will be transmitted and ACK should

be received

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA

No TWDR action or

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”

Data byte in TWDR has

been transmitted;

NOT ACK has been

received

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA; a START

condition will be transmitted when the bus

becomes free

$C0

No TWDR action or

No TWDR action

1

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”; a START condition

will be transmitted when the bus becomes

free

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA

No TWDR action or

0

1

0

1

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”

Last data byte in TWDR

has been transmitted

(TWAE = “0”);

Switched to the not addressed Slave mode;

no recognition of own SLA or GCA; a START

condition will be transmitted when the bus

becomes free

$C8

No TWDR action or

No TWDR action

1

0

1

0

1

ACK has been received

Switched to the not addressed Slave mode;

own SLA will be recognized; GCA will be

recognized if GC = “1”; a START condition

will be transmitted when the bus becomes

free

156

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-51. Formats and States in the Slave Transmitter Mode

Reception of the own

slave address and one or

more data bytes

S

SLA

R

A

DATA

A

DATA

A

P or S

$A8

A

$B8

$C0

Arbitration lost as master

and addressed as slave

$B0

Last data byte transmitted.

A

All 1's

P or S

$C8

Any number of data bytes

and their associated acknowledge bits

From master to slave

From slave to master

DATA

A

This number (contained in TWSR) corresponds

to a defined state of the 2-wire serial bus

n

Table 4-33. Status Codes for Miscellaneous States

Application Software Response

To TWCR

Status

Code

(TWSR)

Status of the 2-wire

Serial Bus and 2-wire

Serial Hardware

Next Action Taken by 2-wire

Serial Hardware

To/From TWDR

STA

STO

TWINT

TWEA

No relevant state

information available;

TWINT = “0”

$F8

$00

No TWDR action

No TWCR action

Wait or proceed current transfer

Only the internal hardware is affected; no

STOP condition is sent on the bus. In all

cases, the bus is released and TWSTO is

cleared.

Bus error due to an

illegal START or STOP

condition

No TWDR action

0

1

X

157

1138H–FPSLI–6/05

4.31 I/O Ports

All AVR ports have true read-modify-write functionality when used as general I/O ports. This

means that the direction of one port pin can be changed without unintentionally changing the

direction of any other pin with the SBI and CBI instructions. The same applies for changing drive

value (if configured as output) or enabling/disabling of pull-up resistors (if configured as input).

4.31.1

PortD

PortD is an 8-bit bi-directional I/O port with internal pull-up resistors.

Three I/O memory address locations are allocated for the PortD, one each for the Data Register

– PORTD, $12($32), Data Direction Register – DDRD, $11($31) and the Port D Input Pins –

PIND, $10($30). The Port D Input Pins address is read only, while the Data Register and the

Data Direction Register are read/write.

The PortD output buffers can sink 20 mA. As inputs, PortD pins that are externally pulled Low

will source current if the pull-up resistors are activated.

PortD Data Register – PORTD

Bit

7

6

5

4

3

2

1

0

$12

PORTD7

PORTD6

PORTD5

PORTD4

PORTD3

PORTD2

PORTD1

PORTD0

PORTD

Read/Write

Initial Value

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

PortD Data Direction Register – DDRD

Bit

7

6

5

4

3

2

1

0

$11

DDD7

R/W

0

DDD6

R/W

0

DDD5

R/W

0

DDD4

R/W

0

DDD3

R/W

0

DDD2

R/W

0

DDD1

R/W

0

DDD0

R/W

0

DDRD

Read/Write

Initial Value

PortD Input Pins Address – PIND

Bit

7

6

5

4

3

2

1

0

$10

PIND7

R

PIND6

R

PIND5

R

PIND4

R

PIND3

R

PIND2

R

PIND1

R

PIND0

R

PIND

Read/Write

Initial Value

Pull1

The PortD Input Pins address – PIND – is not a register, and this address enables access to the

physical value on each PortD pin. When reading PORTD, the PortD Data Latch is read, and

when reading PIND, the logical values present on the pins are read.

4.31.1.1

PortD as General Digital I/O

PDn, General I/O pin: The DDDn bit in the DDRD register selects the direction of this pin. If

DDDn is set (one), PDn is configured as an output pin. If DDDn is cleared (zero), PDn is config-

ured as an input pin. If PDn is set (one) when configured as an input pin the MOS pull-up resistor

is activated. To switch the pull-up resistor off the PDn has to be cleared (zero) or the pin has to

be configured as an output pin. The port pins are input with pull-up when a reset condition

becomes active, even if the clock is not running, see Table 4-34.

158

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 4-34. DDDn⁽¹⁾Bits on PortD Pins

DDDn⁽¹⁾

PORTDn⁽¹⁾

I/O

Pull-up

Comment

0

Input

No

Tri-state (High-Z)

PDn will source current if

external pulled low (default)

0

1

Input

Yes

1

0

1

Output

No

Push-pull zero output

Push-pull one output

Note:

1. n: 7,6...0, pin number

Figure 4-52. PortD Schematic Diagram

MOS

PULLUP

DL

RESET

RD

RESET

R

Q

D

DDD*

DL

GTS

WD

RL

RESET

PD*

R

Q

D

PORTD*

WL

RP

GTS: Global Tri-State

DL: Configuration Download

WL: Write PORTD

WD: Write DDRD

RL: Read PORTD Latch

RD: Read DDRD

RP: Read PORTD Pin

4.31.2

PortE

PortE is an 8-bit bi-directional I/O port with internal pull-up resistors.

Three I/O memory address locations are allocated for the PortE, one each for the Data Register

– PORTE, $07($27), Data Direction Register – DDRE, $06($26) and the PortE Input Pins –

PINE, $05($25). The PortE Input Pins address is read only, while the Data Register and the

Data Direction Register are read/write.

The PortE output buffers can sink 20 mA. As inputs, PortE pins that are externally pulled Low

will source current if the pull-up resistors are activated.

All PortE pins have alternate functions as shown in Table 4-35.

159

1138H–FPSLI–6/05

Table 4-35. PortE Pins Alternate Functions Controlled by SCR and AVR I/O Registers

Port Pin

Alternate Function

Input

Output

TX0

PE0

External Timer0 clock

-

(UART0 transmit pin)

RX0

Output compare

Timer0/PWM0

PE1

PE2

PE3

PE4

PE5

PE6

PE7

-

(UART0 receive pin)

TX1

-

(UART1 transmit pin)

RX1

Output compare

Timer2/PWM2

-

(UART1 receive pin)

INT0

External Timer1 clock

-

(external Interrupt0 input)

INT1

Output compare

Timer1B/PWM1B

-

(external Interrupt0 input)

INT2

Output compare

Timer1A/PWM1A

-

(external Interrupt0 input)

INT3

Input capture Counter1

(external Interrupt0 input)

When the pins are used for the alternate function the DDRE and PORTE register has to be set

according to the alternate function description.

PortE Data Register – PORTE

Bit

7

6

5

4

3

2

1

0

$07 ($27)

Read/Write

Initial Value

PORTE7 PORTE6 PORTE5 PORTE4 PORTE3 PORTE2 PORTE1 PORTE0 PORTE

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

R/W

1

PortE Data Direction Register – DDRE

Bit

7

6

5

4

3

2

1

0

$06 ($26)

Read/Write

Initial Value

DDE7

R/W

0

DDE6

R/W

0

DDE5

R/W

0

DDE4

DDE3

R/W

0

DDE2

R/W

0

DDE1

R/W

0

DDE0

R/W

0

DDRE

R/W

0

PortE Input Pins Address – PINE

Bit

7

6

5

4

3

2

1

0

$05 ($25)

Read/Write

Initial Value

PINE7

R

PINE6

R

PINE5

R

PINE4

R

PINE3

R

PINE2

R

PINE1

R

PINE0

R

PINE

Pull1

The PortE Input Pins address – PINE – is not a register, and this address enables access to the

physical value on each PortE pin. When reading PORTE, the PortE Data Latch is read, and

when reading PINE, the logical values present on the pins are read.

160

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

4.31.2.1

LowPortE as General Digital I/O

PEn, General I/O pin: The DDEn bit in the DDRE register selects the direction of this pin. If

DDEn is set (one), PEn is configured as an output pin. If DDEn is cleared (zero), PEn is config-

ured as an input pin. If PEn is set (one) when configured as an input pin, the MOS pull-up

resistor is activated. To switch the pull-up resistor off the PEn has to be cleared (zero) or the pin

has to be configured as an output pin. The port pins are input with pull-up when a reset condition

becomes active, even if the clock is not running.

Table 4-36. DDEn⁽¹⁾Bits on PortE Pins

DDEn⁽¹⁾

PORTEn⁽¹⁾

I/O

Pull-up

Comment

0

Input

No

Tri-state (High-Z)

PDn⁽¹⁾will source current

if external pulled Low (default).

0

1

Input

Yes

1

0

1

Output

No

Push-pull zero output

Push-pull one output

Note:

1. n: 7,6...0, pin number

4.31.2.2

Alternate Functions of PortE

• PortE, Bit 0

UART0 Transmit Pin.

• PortE, Bit 1

UART0 Receive Pin. Receive Data (Data input pin for the UART0). When the UART0 receiver is

enabled this pin is configured as an input regardless of the value of DDRE0. When the UART0

forces this pin to be an input, a logic 1 in PORTE0 will turn on the internal pull-up.

• PortE, Bit 2

UART1 Transmit Pin. The alternate functions of Port E as UART0 pins are enabled by setting bit

SCR52 in the FPSLIC System Control Register. This is necessary only in smaller pinout pack-

ages where the UART signals are not bonded out. The alternate functions of Port E as UART1

pins are enabled by setting bit SCR53 in the FPSLIC System Control Register.

• PortE, Bit 3

UART1 Receive Pin. Receive Data (Data input pin for the UART1). When the UART1 receiver is

enabled this pin is configured as an input regardless of the value of DDRE2. When the UART1

forces this pin to be an input, a logic 1 in PORTE2 will turn on the internal pull-up.

• PortE, Bit 4-7

External Interrupt sources 0/1/2/3: The PE4 – PE7 pins can serve as external interrupt sources

to the MCU. Interrupts can be triggered by low-level on these pins. The internal pull-up MOS

resistors can be activated as described above.

The alternate functions of PortE as Interrupt pins by setting a bit in the System Control Register.

INT0 is controlled by SCR48. INT1 is controlled by SCR49. INT2 is controlled by SCR50. INT3 is

controlled by SCR51.

PortE, Bit 7 also shares a pin with the configuration control signal CHECK. Lowering CON to ini-

tiate an FPSLIC download (whether for loading or Checking) causes the PE7/CHECK pin to

161

1138H–FPSLI–6/05

immediately tri-state. This function happens only if the Check pin has been enabled in the sys-

tem control register. The use of the Check pin will NOT disable the use of that pin as an input to

PE7 nor as an input as alternate INT3.

4.31.2.3

4.31.2.4

Alternate I/O Functions of PortE

PortE may also be used for various Timer/Counter functions, such as External Input Clocks

(TC0 and TC1), Input Capture (TC1), Pulse Width Modulation (TC0, TC1 and TC2), and toggling

upon an Output Compare (TC0, TC1 and TC2). For a detailed pinout description, consult Table

4-35 on page 160. For more information on the function of each pin, See “Timer/Counters” on

page 89.

PortE Schematics

Note that all port pins are synchronized. The synchronization latches are, however, not shown in

the figures.

Figure 4-53. PortE Schematic Diagram (Pin PE0)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE0

DL

GTS

WD

TX0ENABLE

SCR(52)

RL

0

TX0D

RESET

PE0

R

1

Q

D

PORTE0

WL

RP

T0

GTS: Global Tri-state

DL: Configuration Download

WL: Write PORTE

TX0ENABLE

SCR(52)

WD: Write DDRE

MOS

PULL-UP

RL: Read PORTE Latch

RD: Read DDRE

DL

RP: Read PORTE Pin

RESET

TX0D: UART 0 Transmit Data

TX0ENABLE: UART 0 Transmit Enable

SCR: System Control Register

T0: Timer/Counter0 Clock

DL

GTS

TX0

TX0D

162

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-54. PortE Schematic Diagram (Pin PE1)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE1

DL

WD

GTS

SCR(52)

RL

0

RESET

PE1

R

OC0/PMW0

1

Q

D

PORTE1

COM00

COM01

WL

RP

GTS: Global Tri-State

DL: Configuration Download

WL: Write PORTE

SCR(52)

WD: Write DDRE

MOS

PULL-UP

RL: Read PORTE Latch

RD: Read DDRE

0

1

RP: Read PORTE Pin

RX0D: UART 0 Receive Data

SCR: System Control Register

RX0D

OC0/PMW0: Timer/Counter 0 Output Compare

COM0*: Timer/Counter0 Control Bits

RX0

163

1138H–FPSLI–6/05

Figure 4-55. PortE Schematic Diagram (Pin PE2)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE2

DL

GTS

WD

TX1ENABLE

SCR(53)

RL

0

1

TX1D

RESET

PE2

R

Q

D

PORTE2

WL

RP

TX1ENABLE

SCR(53)

MOS

PULL-UP

GTS: Global Tri-State

DL

DL: Configuration Download

WL: Write PORTE

RESET

WD: Write DDRE

RL: Read PORTE Latch

RD: Read DDRE

DL

GTS

TX1

TX1D

RP: Read PORTE Pin

TX1D: UART 1 Transmit Data

TX1ENABLE: UART 1 Transmit Enable

SCR: System Control Register

164

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-56. PortE Schematic Diagram (Pin PE3)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE3

DL

WD

GTS

SCR(53)

RL

0

RESET

PE3

R

OC2/PMW2

1

Q

D

PORTE3

COM20

COM21

WL

RP

SCR(53)

GTS: Global Tri-State

MOS

DL: Configuration Download

WL: Write PORTE

PULL-UP

0

1

RX1D

WD: Write DDRE

RL: Read PORTE Latch

RD: Read DDRE

RP: Read PORTE Pin

RX1D: UART 1 Receive Data

SCR: System Control Register

RX1

OC2/PMW2: Timer/Counter 2 Output Compare

COM2*: Timer/Counter2 Control Bits

165

1138H–FPSLI–6/05

Figure 4-57. PortE Schematic Diagram (Pin PE4)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE4

DL

WD

GTS

SCR(48)

RL

RESET

PE4

R

Q

D

PORTE4

WL

RP

T1

SCR(48)

MOS

PULL-UP

0

GTS: Global Tri-State

DL: Configuration Download

WL: Write PORTE

extintp0

WD: Write DDRE

RL: Read PORTE Latch

RD: Read DDRE

1

RP: Read PORTE Pin

extintp0: External Interrupt 0

SCR: System Control Register

T1: Timer/Counter1 External Clock

INTP0

166

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-58. PortE Schematic Diagram (Pin PE5)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE5

DL

WD

GTS

SCR(49)

RL

0

RESET

PE5

R

OC1B

1

Q

D

PORTE5

COM1B0

COM1B1

WL

RP

GTS: Global Tri-State

DL: Configuration Download

WL: Write PORTE

WD: Write DDRE

SCR(49)

RL: Read PORTE Latch

RD: Read DDRE

MOS

PULL-UP

0

RP: Read PORTE Pin

extintp1: External Interrupt 1

SCR: System Control Register

extintp1

OC1B: Timer/Counter1 Output Compare B

COM1B*: Timer/Counter1 B Control Bits

1

INTP1

167

1138H–FPSLI–6/05

Figure 4-59. PortE Schematic Diagram (Pin PE6)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE6

DL

WD

GTS

SCR(50)

RL

0

RESET

PE6

R

OC1A

1

Q

D

PORTE6

COM1A0

COM1A1

WL

RP

GTS: Global Tri-State

DL: Configuration Download

WL: Write PORTE

SCR(50)

WD: Write DDRE

MOS

PULL-UP

RL: Read PORTE Latch

RD: Read DDRE

0

RP: Read PORTE Pin

extintp2: External Interrupt 2

SCR: System Control Register

extintp2

1

OC1A: Timer/Counter1 Output Compare A

COM1A*: Timer/Counter1 A Control Bits

INTP2

168

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Figure 4-60. PortE Schematic Diagram (Pin PE7)

MOS

PULL-UP

DL

RESET

RD

RESET

R

Q

D

DDE7

DL

WD

GTS

SCR(51)

RL

RESET

PE7

R

Q

D

PORTE7

WL

RP

ICP

SCR(51)

MOS

PULL-UP

0

GTS: Global Tri-State

DL: Configuration Download

WL: Write PORTE

extintp3

WD: Write DDRE

RL: Read PORTE Latch

RD: Read DDRE

1

RP: Read PORTE Pin

extintp3: External Interrupt 3

SCR: System Control Register

INTP3

ICP: Timer/Counter Input Capture Pin

169

1138H–FPSLI–6/05

5. AC & DC Timing Characteristics

5.1

Absolute Maximum Ratings*⁽¹⁾

*NOTICE:

Stresses beyond those listed under Absolute

Maximum Ratings may cause permanent dam-

age to the device. This is a stress rating only and

functional operation of the device at these or any

other conditions beyond those listed under oper-

ating conditions is not implied. Exposure to Abso-

lute Maximum Rating conditions for extended

periods of time may affect device reliability.

Operating Temperature.................................. -55°C to +125°C

Storage Temperature..................................... -65°C to +150°C

Voltage⁽²⁾on Any Pin

with Respect to Ground.....................................-0.5V to +5.0V

Supply Voltage (V_CC) .........................................-0.5V to +5.0V

Maximum Soldering Temp. (10 sec. @ 1/16 in.).............250°C

ESD (R_ZAP= 1.5K, C_ZAP= 100 pF)................................. 2000V

Notes: 1. For AL parts only

2. Minimum voltage of -0.5V DC which may undershoot to -2.0V for pulses of less than 20 ns.

5.2

DC and AC Operating Range – 3.3V Operation

AT94K

Commercial

Industrial

Operating Temperature (Case)

0°C - 70°C

3.3V ± 0.3V

-40°C - 85°C

3.3V ± 0.3V

V_CCPower Supply

High (V_IHC

)

70% - 100% V_CC

0 - 30% V_CC

70% - 100% V_CC

0 - 30% V_CC

Input Voltage Level (CMOS)

Low (V_ILC

)

170

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

5.3

DC Characteristics – 3.3V Operation – Commercial/Industrial (Preliminary)

T_A= -40°C to 85°C, V_CC= 2.7V to 3.6V (unless otherwise noted⁽¹⁾)

Symbol

Parameter

Conditions

CMOS

XTAL

Minimum⁽³⁾

Typical

Maximum⁽²⁾

5.5

Units

V_IH

High-level Input Voltage

Input High-voltage

Low-level Input Voltage

Input Low-voltage

0.7 V_CC

–

V

(3)

V_IH1

V_IH2

V_IL

0.7 V_CC

V_CC+ 0.5

30% V_CC

0.1⁽²⁾

(3)

RESET

CMOS

XTAL

0.85 V_CC

-0.3

-0.5

V_IL1

I

_OH= 4 mA

2.1

–

V

V_CC= V_CCMinimum

I_OH= 12 mA

V_CC= 3.0V

V_OH

High-level Output Voltage

Low-level Output Voltage

I_OH= 16 mA

V

–

_CC= 3.0V

I_OL= -4 mA

0.4

V_CC= 3.0V

I_OL= -12 mA

V_CC= 3.0V

V_OL

–

I_OL= -16 mA

V_CC= 3.0V

–

RRST

R_I/O

Reset Pull-up

I/O Pin Pull-up

100

35

–

500

120

10

kΩ

µA

mA

µA

V

_IN= V_CCMaximum

With Pull-down, V_IN= V_CC

_IN= V_SS

–

I_IH

High-level Input Current

Low-level Input Current

75

150

–

300

–

V

-10

-300

I_IL

With Pull-up, V_IN= V_SS

-150

-75

10

Without Pull-down, V_IN= V_CCMaximum

With Pull-down, V_IN= V_CCMaximum

Without Pull-up, V_IN= V_SS

High-level Tri-state Output

Leakage Current

I_OZH

75

-10

-300

–

150

300

Low-level Tri-state Output

Leakage Current

I_OZL

With Pull-up, V_IN= V_SS

-150

0.6

80⁽⁴⁾

–

-75

0.5

–

Standby Current Consumption

Power Supply Current

Standby, Unprogrammed

Active, V_CC= 3V⁽¹⁾25 MHz

Idle, V_CC= 3V⁽¹⁾

–

1.0

500

Power-down, V_CC= 3V⁽¹⁾WDT Enable

–

60

Power-down, V_CC= 3V⁽¹⁾

WDT Disable

I_CC

–

30

50

200

400

µA

Power-save, V_CC= 3V⁽¹⁾

WDT Disable

FPGA Core Current

Consumption

–

2

–

mA/MHz

pF

C_IN

Input Capacitance

All Pins

10

Notes: 1. Complete FPSLIC device with static FPGA core (no clock in FPGA active).

2. “Maximum” is the highest value where the pin is guaranteed to be read as Low.

3. “Minimum” is the lowest value where the pin is guaranteed to be read as High.

4. 54 mA for AT94K05 devices.

171

1138H–FPSLI–6/05

6. Power-On Power Supply Requirements

Atmel FPGAs require a minimum rated power supply current capacity to insure proper initializa-

tion, and the power supply ramp-up time does affect the current required. A fast ramp-up time

requires more current than a slow ramp-up time.

Table 6-1.

Device

Power-On Power Supply Requirements⁽¹⁾

Description

Maximum Current⁽²⁾⁽³⁾

50 mA

AT94K05AL

AT94K10AL

Maximum Current Supply

AT94K40AL

100 mA

Notes: 1. This specification applies to Commercial and Industrial grade products only.

2. Devices are guaranteed to initialize properly at 50% of the minimum current listed above. A

larger capacity power supply may result in a larger initialization current.

3. Ramp-up time is measured from 0 V DC to 3.6 V DC. Peak current required lasts less than 2

ms, and occurs near the internal power on reset threshold voltage.

172

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

6.1

FPSLIC Dual-port SRAM Characteristics

The Dual-port SRAM operates in single-edge clock controlled mode during read operations, and

a double-edge controlled mode during write operations. Addresses are clocked internally on the

rising edge of the clock signal (ME). Any change of address without a rising edge of ME is not

considered.

In read mode, the rising clock edge triggers data read without any significant constraint on the

length of the clock pulse. The WE signal must be changed and held Low before the rising edge

of ME to signify a read cycle. The WE signal should then remain Low until the falling edge of the

clock.

In write mode, data applied to the inputs is latched on either the falling edge of WE or the falling

edge of the clock, whichever comes earlier, and written to memory. Also, WE must be High

before the rising edge of ME to signify a write cycle. If data inputs change during a write cycle,

only the value present at the write cycle end is considered and written to the address clocked at

the ME rise. A write cycle ending on WE fall does not turn into a read cycle – the next cycle will

be a read cycle if WE remains Low during rising edge of ME.

Figure 6-1. SRAM Read Cycle Timing Diagram

ADDR

Address Valid

t_ADH

t_ADS- Address Setup

t_ADS

t_ADH- Address Hold

t_MEL

t_RDS- Read Cycle Setup

t_RDH- Read Cycle Hold

t_ACC- Access Time from posedge ME

t_MEH- Minimum ME High

t_MEL- Minimum ME Low

CLK (ME)

WE

t_MEH

t_RDH

t_RDS

t_ACC

Previous Data

DATA READ

Output Valid

Figure 6-2. SRAM Write Cycle Timing Diagram

ADDR

Address Valid

t_ADS

- Address Setup

t_ADH

t_ADS

t_ADH

- Address Hold

t

_WRS- Write Cycle Setup

_MPW- Minimum Write Duration

_WDS- Data Setup to Write End

_WDH- Data Hold to Write End

CLK (ME)

t_MPW

t_WRS

WE

t_WDS

t_WDH

Data Valid

DATA WRITE

173

1138H–FPSLI–6/05

6.1.1

Frame Interface

The FPGA Frame Clock phase is selectable (see “System Control Register – FPGA/AVR” on

page 30). This document refers to the clock at the FPGA/Dual-port SRAM interface as ME (the

relation of ME to data, address and write enable does not change). By default, FrameClock is

inverted (ME = ~FrameClock). Selecting the non-inverted phase assigns ME = FrameClock.

Recall, the Dual-port SRAM operates in single-edge clock controlled mode during read opera-

tions, and double-edge clock controlled mode during writes. Addresses are clocked internally on

the rising edge of the clock signal (ME). Any change of address without a rising edge of ME is

not considered.

Table 6-2.

SRAM Read Cycle Timing Numbers

Commercial 3.3V ± 10%/Industrial 3.3V ± 10%

Commercial

Industrial

Symbol Parameter

Minimum

Typical

0.8

0.9

0

Maximum Minimum

Typical

0.8

0.9

0

Maximum Units

t_ADS

t_ADH

t_RDS

t_RDH

t_ACC

t_MEH

t_MEl

Address Setup

0.6

0.7

0

1.1

1.3

0

0.5

0.6

0

1.2

1.5

0

ns

Address Hold

Read Cycle Setup

Read Cycle Hold

0

Access Time from Posedge ME

Minimum ME High

Minimum ME Low

3.4

0.7

0.6

4.2

0.9

0.8

5.9

1.3

1.1

2.9

0.6

4.2

0.9

0.8

6.9

1.5

1.3

Table 6-3.

SRAM Write Cycle Timing Numbers

Commercial 3.3V ± 10%/Industrial 3.3V ± 10%

Commercial

Industrial

Typical

0.8

Symbol Parameter

Minimum

Typical

0.8

Maximum Minimum

Maximum Units

t_ADS

t_ADH

t_WRS

t_MPW

t_WDS

t_WDH

Address Setup

0.6

0.7

0

1.1

1.3

0

0.5

0.6

0

1.2

1.5

0

ns

Address Hold

0.9

Write Cycle Setup

0

Minimum Write Duration

Data Setup to Write End

Data Hold to Write End

1.4

4.6

0.6

1.8

2.5

8.0

1.1

1.2

3.9

0.5

1.8

3.0

9.4

1.3

5.7

0.8

174

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 6-4.

FPSLIC Interface Timing Information⁽¹⁾

3.3V Commercial ± 10%

Maximu

3.3V Industrial ± 10%

Maximu

m

Symbol

Parameter

Minimum

Typical

m

Minimum

Typical

Units

Clock Delay From XTAL2 Pad

to GCK_5 Access to FPGA Core

t_IXG4

3.6

4.8

7.6

3.4

4.8

7.9

8.8

6.9

7.8

ns

Clock Delay From XTAL2 Pad

to GCK_6 Access to FPGA Core

t_IXG5

t_IXC

t_IXI

3.9

2.8

3.5

5.2

3.7

4.7

8.1

6.3

7.5

3.6

2.5

3.2

5.2

3.7

4.7

ns

Clock Delay From XTAL2 Pad

to AVR Core Clock

Clock Delay From XTAL2 Pad

to AVR I/O Clock

AVR Core Clock to FPGA

I/O Read Enable

t_CFIR

t_CFIW

5.3

5.2

6.6

7.9

4.4

6.6

9.2

ns

AVR Core Clock to

FPGA I/O Write Enable

AVR Core Clock to

FPGA I/O Select Active

t_CFIS

t_FIRQ

6.3

0.2

7.8

0.2

9.4

0.3

5.3

0.1

7.8

0.2

11.0

0.3

ns

FPGA Interrupt Net

Propagation Delay to AVR Core

FPGA SRAM Clock to

On-chip SRAM

t_IFS

6.1

4.4

5.4

1.3

0.2

7.7

5.5

6.7

1.7

0.2

7.7

5.5

6.7

2.0

0.2

4.9

3.7

4.3

1.3

0.2

7.7

5.5

6.7

1.7

0.2

7.7

5.5

6.7

2.0

0.2

ns

FPGA SRAM Write

Stobe to On-chip SRAM

t_FRWS

t_FAS

t_FDWS

t_FDRS

Note:

FPGA SRAM Address Valid to

On-chip SRAM Address Valid

FPGA Write Data Valid

to On-chip SRAM Data Valid

On-chip SRAM Data Valid to

FPGA Read Data Valid

1. Insertion delays are specified from XTAL2. These delays are more meaningful because the XTAL1-to-XTAL2 delay is sensi-

tive to system loading on XTAL2. If it is necessary to drive external devices with the system clock, devices should use XTAL2

output pin. Remember that XTAL2 is inverted in comparison to XTAL1.

175

1138H–FPSLI–6/05

6.2

External Clock Drive Waveforms

Figure 6-3. External Clock Drive Waveforms

VIH1

VIL1

Table 6-5.

Symbol

1/t_CLCL

t_CLCL

External Clock Drive, V_CC= 3.0V to 3.6V

Parameter

Oscillator Frequency

Clock Period

High Time

Minimum

Maximum

Units

MHz

ns

0

40

15

–

25

–

t_CHCX

–

ns

t_CLCX

Low Time

–

ns

t_CLCH

Rise Time

1.6

µs

t_CHCL

Fall Time

–

µs

176

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

6.3

AC Timing Characteristics – 3.3V Operation

Delays are based on fixed loads and are described in the notes.

Maximum times based on worst case: V_CC= 3.00V, temperature = 70°C

Minimum times based on best case: V_CC= 3.60V, temperature = 0°C

Maximum delays are the average of t_PDLHand t_PDHL

Cell Function Parameter

Core

.

Path

-25

Units

Notes

2 Input Gate

3 Input Gate

4 Input Gate

Fast Carry

DFF

t

_PD(Maximum)

x/y -> x/y

x/y/z -> x/y

x/y/w -> x/y

x/y/w/z -> x/y

y -> y

2.9

2.8

3.4

2.3

2.9

3.0

2.3

3.4

2.4

2.8

–

ns

–

1 Unit Load

–

t_PD(Maximum)

x -> y

t_PD(Maximum)

y -> x

t_PD(Maximum)

x -> x

w -> y

t_PD(Maximum)

w -> x

t_PD(Maximum)

z -> y

z -> x

t_PD(Maximum)

q -> x/y

x/y -> clk

R -> x/y

S -> x/y

q -> w

DFF

t_setup(Minimum)

t_hold(Minimum)

DFF

–

DFF

t_PD(Maximum)

3.2

3.0

2.7

2.4

2.8

2.4

ns

1 Unit Load

–

DFF

t_PD(Maximum)

DFF

incremental -> L

Local Output Enable

t_PD(Maximum)

x/y -> L

oe -> L

–

t_PZX(Maximum)

t_PXZ(Maximum)

1 Unit Load

177

1138H–FPSLI–6/05

6.4

AC Timing Characteristics – 3.3V Operation

Delays are based on fixed loads and are described in the notes.

Maximum times based on worst case: V_CC= 3.0V, temperature = 70°C

Minimum times based on best case: V_CC= 3.6V, temperature = 0°C

Maximum delays are the average of t_PDLHand t_PDHL

All input IO characteristics measured from a V_IHof 50% of V_DDat the pad (CMOS threshold) to the internal V_IHof 50% of V_DD. All

output IO characteristics are measured as the average of t_PDLHand t_PDHLto the pad V_IHof 50% of V_DD

.

Cell Function

Parameter

Path

-25

Units

Notes

Repeaters

Repeater

t_PD(Maximum)

L -> E

E -> E

L -> L

2.2

1.4

ns

1 Unit Load

t_PD(Maximum)

E -> L

E -> IO

L -> IO

t_PD(Maximum)

All input IO characteristics measured from a V_IHof 50% of V_DDat the pad (CMOS threshold) to the internal V_IHof 50% of

_DD. All output IO characteristics are measured as the average of t_PDLHand t_PDHLto the pad V_IHof 50% of V_DD

V

.

Cell Function

Parameter

Path

-25

Units

Notes

IO

Input

t_PD(Maximum)

pad -> x/y

x/y/E/L -> pad

oe -> pad

1.9

5.8

11.5

17.4

9.1

7.6

6.2

9.5

2.1

7.4

2.7

5.9

2.4

ns

No Extra Delay

1 Extra Delay

2 Extra Delays

3 Extra Delays

50 pf Load

Input

t_PD(Maximum)

Input

t_PD(Maximum)

Input

Output, Slow

Output, Medium

Output, Fast

Output, Slow

Output, Medium

Output, Fast

t_PD(Maximum)

50 pf Load

t_PZX(Maximum)

50 pf Load

t_PXZ(Maximum)

t_PZX(Maximum)

oe -> pad

50 pf Load

oe -> pad

50 pf Load

t

_PXZ(Maximum)

oe -> pad

50 pf Load

t_PZX(Maximum)

t_PXZ(Maximum)

oe -> pad

50 pf Load

oe -> pad

50 pf Load

178

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

6.5

AC Timing Characteristics – 3.3V Operation

Delays are based on fixed loads and are described in the notes.

Maximum times based on worst case: V_CC= 3.0V, temperature = 70°C

Minimum times based on best case: V_CC= 3.6V, temperature = 0°C

Maximum delays are the average of t_PDLHand t_PDHL

.

Clocks and Reset Input buffers are measured from a V_IHof 1.5V at the input pad to the internal V_IHof 50% of V_CC

Maximum times for clock input buffers and internal drivers are measured for rising edge delays only.

.

Cell Function

Parameter

Path

Device

-25

Units

Notes

Global Clocks and Set/Reset

AT94K05

AT94K10

AT94K40

1.2

1.5

1.9

pad -> clock

ns

t_PD

(Maximum)

GCK Input Buffer

Rising Edge Clock

–

AT94K05

AT94K10

AT94K40

0.7

0.8

0.9

pad -> clock

ns

t_PD

(Maximum)

FCK Input Buffer

AT94K05

AT94K10

AT94K40

1.3

1.8

2.5

clock -> colclk

ns

t_PD

(Maximum)

Clock Column Driver

Clock Sector Driver

GSRN Input Buffer

AT94K05

AT94K10

AT94K40

1.0

colclk -> secclk

ns

t_PD

(Maximum)

AT94K05

AT94K10

AT94K40

colclk -> secclk

5.4

8.2

ns

t_PD

(Maximum)

Rising Edge Clock

Fully Loaded Clock Tree

Rising Edge DFF

AT94K05

AT94K10

AT94K40

12.6

13.4

14.5

clock pad -> out

t_PD

(Maximum)

ns

Global Clock to Output

Fast Clock to Output

20 mA Output Buffer

50 pf Pin Load

Rising Edge Clock

Fully Loaded Clock Tree

Rising Edge DFF

AT94K05

AT94K10

AT94K40

12.1

12.7

13.5

clock pad -> out

ns

t_PD

(Maximum)

20 mA Output Buffer

50 pf Pin Load

179

1138H–FPSLI–6/05

6.6

AC Timing Characteristics – 3.3V Operation

Delays are based on fixed loads and are described in the notes.

Maximum times based on worst case: V_CC= 3.0V, temperature = 70°C

Minimum times based on best case: V_CC= 3.6V, temperature = 0°C

Cell Function

Parameter

Path

-25

Units

Notes

Async RAM

Write

t_WECYC(Minimum)

cycle time

12.0

5.0

5.3

0.0

5.0

0.0

8.7

6.3

2.9

3.5

ns

–

Write

t

_WEL(Minimum)

we

Pulse Width Low

Pulse Width High

Write

t_WEH(Minimum)

t_setup(Minimum)

we

Write

wr addr setup-> we

wr addr hold -> we

din setup -> we

din hold -> we

oe hold -> we

din -> dout

Write

t

_hold(Minimum)

–

Write

t_setup(Minimum)

t_hold(Minimum)

Write

–

Write

t_hold(Minimum)

Write/Read

Read

t_PD(Maximum)

rd addr = wr addr

–

rd addr -> dout

oe -> dout

Read

t_PZX(Maximum)

Read

t_PXZ(Maximum)

oe -> dout

Sync RAM

Write

t_CYC(Minimum)

t_CLKL(Minimum)

t_CLKH(Minimum)

cycle time

12.0

5.0

3.2

0.0

5.0

0.0

3.9

0.0

8.7

5.8

6.3

2.9

3.5

ns

Write

clk

–

Write

clk

Pulse Width High

Write

t

_setup(Minimum)

we setup-> clk

we hold -> clk

wr addr setup-> clk

wr addr hold -> clk

wr data setup-> clk

wr data hold -> clk

din -> dout

Write

t_hold(Minimum)

t_setup(Minimum)

–

Write

t_hold(Minimum)

Write

t_setup(Minimum)

t_hold(Minimum)

Write

–

Write/Read

Read

t

_PD(Maximum)

rd addr = wr addr

t_PD(Maximum)

clk -> dout

rd addr -> dout

oe -> dout

Read

t

_PZX(Maximum)

–

Read

t_PXZ(Maximum)

oe -> dout

CMOS buffer delays are measured from a V_IHof 1/2 V_CCat the pad to the internal V_IHat A. The input buffer load is con-

stant. Buffer delay is to a pad voltage of 1.5V with one output switching. Parameter based on characterization and

simulation; not tested in production. An FPGA power calculation is available in Atmel’s System Designer software (see also

page 171).

180

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

7. Packaging and Pin List Information

FPSLIC devices should be laid out to support a split power supply for both AL and AX families.

Please refer to the “Designing in Split Power Supply Support for AT94KAL and AT94SAL

Devices” application note, available on the Atmel web site.

Table 7-1.

Part #

Part and Package Combinations Available

Package

AJ

AT94K05

AT94K10

46

AT94K40

PLCC 84

TQ 100

LQ144

46

58

82

96

AQ

58

BQ

84

PQ 208

DQ

116

120

Table 7-2.

AT94K JTAG ICE Pin List

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

TDI

IO34

IO38

IO43

IO44

IO50

IO98

TDO

TMS

TCK

IO54

IO102

IO63

IO123

IO64

IO124

Table 7-3.

AT94K Pin List

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

West Side

GND

12

13

14

1

2

3

1

2

4

I/O1, GCK1

(A16)

I/O1, GCK1

(A16)

I/O1, GCK1

(A16)

I/O2 (A17)

I/O3

I/O2 (A17)

I/O3

I/O2 (A17)

I/O3

3

4

5

6

7

5

6

7

8

9

I/O4

I/O5 (A18)

I/O6 (A19)

I/O5 (A18)

I/O6 (A19)

I/O5 (A18)

I/O6 (A19)

GND

15

16

4

5

I/O7

I/O8

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

181

1138H–FPSLI–6/05

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

I/O9

I/O10

I/O11

I/O12

VCC⁽¹⁾

GND

I/O13

I/O14

I/O7

I/O8

I/O7

I/O8

I/O15

10

11

12

13

I/O16

I/O9

I/O17

I/O10

I/O18

GND

I/O19

I/O20

I/O11

I/O12

I/O21

I/O22

I/O23

I/O24

GND

I/O13, FCK1

I/O14

GND

8

14

15

16

17

18

I/O9, FCK1

I/O10

I/O25, FCK1

I/O26

9

10

11

12

I/O11 (A20)

I/O12 (A21)

I/O15 (A20)

I/O16 (A21)

VCC⁽¹⁾

I/O27 (A20)

I/O28 (A21)

VCC⁽¹⁾

I/O29

17

18

6

7

I/O17

I/O18

I/O30

GND

I/O31

I/O32

I/O33

I/O34

I/O35

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

182

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

I/O36

GND

VCC⁽¹⁾

I/O37

I/O38

I/O39

I/O40

I/O19

I/O20

I/O41

19

20

I/O42

GND

I/O13

I/O14

I/O21

I/O22

I/O43

13

14

21

22

I/O44

8

I/O45

I/O46

I/O15 (A22)

I/O16 (A23)

GND

I/O23 (A22)

I/O24 (A23)

GND

I/O47 (A22)

I/O48 (A23)

GND

19

20

21

22

23

24

9

15

16

17

18

19

20

23

24

25

26

27

28

10

11

12

13

14

VDD⁽²⁾

I/O49 (A24)

I/O50 (A25)

I/O51

I/O17 (A24)

I/O18 (A25)

I/O25 (A24)

I/O26 (A25)

I/O52

I/O19

I/O20

I/O27

I/O28

I/O53

15

21

22

29

30

I/O54

GND

I/O29

I/O30

I/O55

31

32

I/O56

I/O57

I/O58

I/O59

I/O60

VCC⁽¹⁾

GND

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

183

1138H–FPSLI–6/05

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

I/O61

I/O62

I/O63

I/O64

I/O65

I/O66

GND

I/O31

I/O32

I/O67

I/O68

VDD⁽²⁾

I/O69 (A26)

I/O70 (A27)

I/O71

I/O21 (A26)

I/O22 (A27)

I/O23

I/O33 (A26)

I/O34 (A27)

I/O35

25

26

16

17

23

24

25

26

27

33

34

35

36

37

I/O24, FCK2

GND

I/O36, FCK2

GND

I/O72, FCK2

GND

I/O73

I/O74

I/O37

I/O38

I/O75

I/O76

I/O77

I/O78

GND

I/O79

I/O80

I/O39

I/O40

I/O41

I/O42

I/O81

38

39

40

41

I/O82

I/O25

I/O26

I/O83

I/O84

GND

VCC⁽¹⁾

I/O85

I/O86

I/O87

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

184

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

I/O88

I/O27 (A28)

I/O28

I/O43 (A28)

I/O44

I/O89 (A28)

I/O90

27

18

19

28

29

42

43

GND

I/O91

I/O92

I/O29

I/O30

I/O45

I/O46

I/O93

30

31

32

44

45

46

I/O94

I/O31 (OTS)

I/O47 (OTS)

I/O95 (OTS)

28

29

20

21

I/O32, GCK2

(A29)

I/O48, GCK2

(A29)

I/O96, GCK2

(A29)

33

47

AVRRESET

GND

AVRRESET

GND

AVRRESET

GND

30

31

32

22

23

24

34

35

36

48

49

50

M0

South Side

VCC⁽¹⁾

M2

VCC⁽¹⁾

M2

VCC⁽¹⁾

M2

33

34

35

25

26

27

37

38

39

55

56

57

I/O33, GCK3

I/O49, GCK3

I/O97, GCK3

I/O98

(HDC/TDI)

I/O34 (HDC/TDI)

I/O50 (HDC/TDI)

36

28

40

58

I/O35

I/O36

I/O51

I/O52

I/O99

41

42

59

60

I/O100

I/O37

Not a User I/O

I/O53

Not a User I/O

I/O101

29

30

43

44

61

62

I/O38

(LDC/TDO)

I/O54

(LDC/TDO)

I/O102

(LDC/TDO)

37

GND

I/O103

I/O104

I/O105

I/O106

I/O107

I/O108

VCC⁽¹⁾

GND

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

185

1138H–FPSLI–6/05

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

I/O109

I/O110

I/O111

I/O112

I/O113

I/O114

GND

PC84

TQ100

PQ144

PQ208

63

I/O39

I/O40

I/O55

I/O56

I/O57

I/O58

64

65

66

I/O115

I/O116

I/O117

I/O118

I/O119

I/O120

GND

I/O59

I/O60

GND

I/O41

GND

I/O61

45

46

47

48

49

67

68

69

70

71

I/O121

I/O122

I/O123/TMS

I/O124/TCK

VCC⁽¹⁾

I/O125

I/O126

GND

I/O42

I/O62

I/O43/TMS

I/O44/TCK

I/O63/TMS

I/O64/TCK

VCC⁽¹⁾

I/O65

38

39

31

32

72

73

I/O66

I/O127

I/O128

I/O129

I/O130

I/O131

I/O132

GND

VCC⁽¹⁾

I/O133

I/O134

I/O135

I/O67

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

186

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

I/O68

I/O69

I/O70

I/O136

I/O45

I/O46

I/O137

33

34

50

51

74

75

I/O138

GND

I/O139

I/O140

I/O141

I/O142

I/O47 (TD7)

I/O48 (InitErr)

VDD⁽²⁾

I/O71 (TD7)

I/O72 (InitErr)

VDD⁽²⁾

I/O143 (TD7)

I/O144 (InitErr)

VDD⁽²⁾

40

41

42

43

44

45

35

36

37

38

39

40

52

53

54

55

56

57

76

77

78

79

80

81

GND

I/O49 (TD6)

I/O50 (TD5)

I/O73 (TD6)

I/O74 (TD5)

I/O145 (TD6)

I/O146 (TD5)

I/O147

I/O148

I/O149

I/O150

GND

I/O51

I/O52

I/O75

I/O76

I/O77

I/O78

I/O151

41

42

58

59

82

83

84

85

I/O152

I/O153

I/O154

I/O155

I/O156

VCC⁽¹⁾

GND

I/O157

I/O158

I/O159

I/O160

I/O161

I/O162

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

187

1138H–FPSLI–6/05

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

GND

I/O79

I/O80

I/O163

I/O164

VCC⁽¹⁾

I/O53 (TD4)

I/O54 (TD3)

I/O55

I/O81 (TD4)

I/O82 (TD3)

I/O83

I/O165 (TD4)

I/O166 (TD3)

I/O167

46

47

43

44

60

61

62

63

64

86

87

88

89

90

I/O56

I/O84

I/O168

GND

I/O169

I/O170

I/O85

I/O86

I/O171

I/O172

I/O173

I/O174

GND

I/O175

I/O176

I/O87

I/O88

I/O89

I/O90

I/O177

91

92

93

94

I/O178

I/O57

I/O58

I/O179

I/O180

GND

VCC⁽¹⁾

I/O181

I/O182

I/O59 (TD2)

I/O60 (TD1)

I/O91 (TD2)

I/O92 (TD1)

I/O183 (TD2)

I/O184 (TD1)

I/O185

48

49

45

46

65

66

95

96

I/O186

GND

I/O187

I/O188

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

188

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

67

PQ208

97

I/O61

I/O62

I/O93

I/O94

I/O189

I/O190

68

98

I/O63 (TD0)

I/O64, GCK4

GND

I/O95 (TD0)

I/O96, GCK4

GND

I/O191 (TD0)

I/O192, GCK4

GND

50

51

52

53

47

48

49

50

69

99

70

100

101

103

71

CON

72

East Side

VCC⁽¹⁾

RESET

PE0

VCC⁽¹⁾

RESET

PE0

VCC⁽¹⁾

RESET

PE0

54

55

56

57

51

52

53

54

73

74

75

76

77

78

106

108

109

110

111

112

PE1

PD0

PD1

GND

VCC⁽¹⁾

GND

PE2

PD2

PE2

PD2

PE2

58

55

56

79

80

113

114

PD2

GND

No Connect

PD3

No Connect

PD3

No Connect

PD3

81

82

83

119

120

121

PD4

VCC⁽¹⁾

PE3

VCC⁽¹⁾

PE3

59

60

57

58

84

85

122

123

CS0, Cs0n

GND

VCC⁽¹⁾

SDA

SCL

SDA

SCL

124

125

SCL

GND

PD5

PD6

PD5

PD6

PD5

59

60

86

87

126

127

PD6

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

189

1138H–FPSLI–6/05

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

61

TQ100

PQ144

88

PQ208

128

PE4

PE5

PE4

PE5

PE4

61

62

63

64

65

PE5

62

89

129

VDD⁽²⁾

GND

PE6

VDD⁽²⁾

GND

PE6

VDD⁽²⁾

GND

63

90

130

64

91

131

PE6

65

92

132

PE7

(CHECK)

PE7 (CHECK)

66

67

93

133

PD7

INTP0

GND

94

95

134

135

INTP0

VCC⁽¹⁾

GND

XTAL1

XTAL2

XTAL1

XTAL2

VDD⁽²⁾

RX0

XTAL1

XTAL2

VDD⁽²⁾

RX0

67

68

69

96

97

138

139

RX0

TX0

98

99

140

141

142

TX0

GND

100

GND

INTP1

INTP2

INTP1

INTP2

INTP1

INTP2

GND

145

146

VCC⁽¹⁾

TOSC1

TOSC2

GND

TOSC1

TOSC2

TOSC1

TOSC2

69

70

71

101

102

147

148

RX1

TX1

RX1

TX1

RX1

103

104

105

106

107

108

149

150

151

152

153

154

TX1

D0

71

72

73

74

72

73

74

75

INTP3 (CSOUT)

CCLK

INTP3 (CSOUT)

CCLK

INTP3 (CSOUT)

CCLK

VCC⁽¹⁾

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

190

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

I/O65:95

I/O97:144

I/O193:288

Are Unbonded⁽³⁾

North Side

Testclock

GND

Testclock

GND

Testclock

GND

75

76

77

76

77

78

109

110

111

159

160

161

I/O97 (A0)

I/O145 (A0)

I/O289 (A0)

I/O98, GCK7

(A1)

I/O146, GCK7

(A1)

I/O290, GCK7

(A1)

78

79

112

162

I/O99

I/O147

I/O148

I/O291

I/O292

I/O293

I/O294

GND

113

114

163

164

I/O100

I/O295

I/O296

I/O101 (CS1,

A2)

I/O149 (CS1,

A2)

I/O297 (CS1,

A2)

79

80

81

115

116

165

166

I/O102 (A3)

I/O150 (A3)

I/O298 (A3)

I/O299

I/O300

VCC⁽¹⁾

GND

Shortedto

Testclock

Shortedto

Testclock

Shortedto

Testclock

Shortedto

Testclock

I/O104

I/O103

I/O151

I/O301

I/O152

I/O153

I/O154

I/O302

I/O303

I/O304

I/O305

I/O306

GND

117

167

168

I/O307

I/O308

I/O309

I/O310

I/O311

I/O155

I/O156

169

170

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

191

1138H–FPSLI–6/05

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

I/O312

GND

PC84

TQ100

PQ144

PQ208

GND

118

119

120

171

172

173

I/O105

I/O106

I/O157

I/O158

I/O159

I/O160

VCC⁽¹⁾

I/O313

I/O314

I/O315

I/O316

VCC⁽¹⁾

I/O317

I/O318

GND

I/O319

I/O320

I/O321

I/O322

I/O323

I/O324

GND

VCC⁽¹⁾

I/O325 (A4)

I/O326 (A5)

GND

I/O107 (A4)

I/O108 (A5)

I/O161 (A4)

I/O162 (A5)

81

82

83

121

122

174

175

I/O163

I/O164

I/O165

I/O166

I/O327

I/O328

I/O329

I/O330

GND

176

177

178

179

I/O109

I/O110

84

85

123

124

I/O331

I/O332

I/O333

I/O334

I/O335 (A6)

I/O336 (A7)

GND

I/O111 (A6)

I/O112 (A7)

GND

I/O167 (A6)

I/O168 (A7)

GND

83

84

1

86

87

88

125

126

127

180

181

182

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

192

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

89

PQ144

128

PQ208

183

VDD⁽²⁾

2

3

4

I/O113 (A8)

I/O114 (A9)

I/O169 (A8)

I/O170 (A9)

I/O337 (A8)

I/O338 (A9)

I/O339

I/O340

I/O341

I/O342

GND

90

129

184

91

130

185

I/O115

I/O116

I/O171

I/O172

I/O343

I/O344

I/O345

I/O346

I/O347 (A10)

I/O348 (A11)

VCC⁽¹⁾

92

93

131

132

186

187

188

189

190

191

I/O173

I/O174

I/O117 (A10)

I/O118 (A11)

I/O175 (A10)

I/O176 (A11)

5

6

94

95

133

134

GND

I/O349

I/O350

I/O351

I/O352

I/O353

I/O354

GND

I/O355

I/O356

VDD⁽²⁾

I/O177

I/O178

I/O179

I/O180

GND

I/O357

I/O358

I/O359

I/O360

GND

I/O119

I/O120

GND

135

136

137

192

193

194

I/O361

I/O362

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

193

1138H–FPSLI–6/05

Table 7-3.

AT94K Pin List (Continued)

Packages

AT94K05

AT94K10

AT94K40

96 FPGA I/O

192 FPGA I/O

384 FPGA I/O

PC84

TQ100

PQ144

PQ208

195

I/O181

I/O182

I/O363

I/O364

196

I/O365

I/O366

GND

I/O367

I/O368

I/O121

I/O122

I/O183

I/O184

I/O369

197

198

199

200

I/O370

I/O123 (A12)

I/O124 (A13)

I/O185 (A12)

I/O186 (A13)

I/O371 (A12)

I/O372 (A13)

GND

7

8

96

97

138

139

VCC⁽¹⁾

I/O373

I/O374

I/O375

I/O376

I/O377

I/O378

GND

I/O187

I/O188

I/O379

I/O380

I/O125

I/O126

I/O189

I/O381

140

141

142

201

202

203

I/O190

I/O382

I/O127 (A14)

I/O191 (A14)

I/O383 (A14)

9

98

99

I/O128, GCK8

(A15)

I/O192, GCK8

(A15)

I/O384, GCK8

(A15)

10

11

143

144

204

205

VCC⁽¹⁾

100

Notes: 1. VCC is I/O high voltage. Please refer to the “Designing in Split Power Supply Support for

AT94KAL and AT94SAL Devices” application note.

2. VDD is core high voltage. Please refer to the “Designing in Split Power Supply Support

for AT94KAL and AT94SAL Devices” application note.

3. Unbonded pins are No Connects.

194

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

8. Ordering Information

Usable Gates

Speed Grade

Ordering Code

Package

Operation Range

AT94K05AL-25AJC

AT94K05AL-25AQC

AT94K05AL-25BQC

AT94K05AL-25DQC

84J

Commercial

100A

144L1

208Q1

(0°C - 70°C)

5,000

-25 MHz

AT94K05AL-25AJI

AT94K05AL-25AQI

AT94K05AL-25BQI

AT94K05AL-25DQI

84J

Industrial

100A

144L1

208Q1

(-40°C - 85°C)

AT94K10AL-25AJC

AT94K10AL-25AQC

AT94K10AL-25BQC

AT94K10AL-25DQC

84J

Commercial

100A

144L1

208Q1

(0°C - 70°C)

10,000

40,000

-25 MHz

AT94K10AL-25AJI

AT94K10AL-25AQI

AT94K10AL-25BQI

AT94K10AL-25DQI

84J

Industrial

100A

144L1

208Q1

(-40°C - 85°C)

Commercial

AT94K40AL-25BQC

AT94K40AL-25DQC

144L1

208Q1

(0°C - 70°C)

Industrial

AT94K40AL-25BQI

AT94K40AL-25DQI

144L1

208Q1

(-40°C - 85°C)

Package Type

84J

84-lead, Plastic J-leaded Chip Carrier (PLCC)

100A

100-lead, Thin (1.0 mm) Plastic Quad Flat Package (TQFP)

144-lead, Low Profile Plastic Gull Wing Quad Flat Package (LQFP)

208-lead, Plastic Gull Wing Quad Flat Package (PQFP)

144L1

208Q1

195

1138H–FPSLI–6/05

9. Packaging Information

9.1

84J – PLCC

1.14(0.045) X 45˚

PIN NO. 1

1.14(0.045) X 45˚

0.318(0.0125)

0.191(0.0075)

IDENTIFIER

D2/E2

E1

E

B1

B

e

A2

A1

D1

D

A

0.51(0.020)MAX

45˚ MAX (3X)

COMMON DIMENSIONS

(Unit of Measure = mm)

MIN

4.191

MAX

4.572

3.048

–

NOM

NOTE

SYMBOL

A

–

A1

A2

D

2.286

–

0.508

–

30.099

29.210

30.099

29.210

–

30.353

D1

E

–

29.413 Note 2

30.353

–

Notes:

1. This package conforms to JEDEC reference MS-018, Variation AF.

2. Dimensions D1 and E1 do not include mold protrusion.

Allowable protrusion is .010"(0.254 mm) per side. Dimension D1

and E1 include mold mismatch and are measured at the extreme

material condition at the upper or lower parting line.

E1

–

29.413 Note 2

28.702

D2/E2 27.686

–

B

0.660

0.330

–

0.813

3. Lead coplanarity is 0.004" (0.102 mm) maximum.

B1

e

0.533

1.270 TYP

10/04/01

DRAWING NO. REV.

TITLE

2325 Orchard Parkway

San Jose, CA 95131

84J, 84-lead, Plastic J-leaded Chip Carrier (PLCC)

84J

B

R

196

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

9.2

100A – TQFP

PIN 1

B

PIN 1 IDENTIFIER

E1

E

e

D1

D

C

0˚~7˚

A2

A

A1

L

COMMON DIMENSIONS

(Unit of Measure = mm)

MIN

–

MAX

1.20

NOM

NOTE

SYMBOL

A

–

A1

A2

D

0.05

0.95

15.75

13.90

15.75

13.90

0.17

0.09

0.45

0.15

1.00

16.00

14.00

16.00

14.00

–

1.05

16.25

D1

E

14.10 Note 2

16.25

Notes:

1. This package conforms to JEDEC reference MS-026, Variation AED.

2. Dimensions D1 and E1 do not include mold protrusion. Allowable

protrusion is 0.25 mm per side. Dimensions D1 and E1 are maximum

plastic body size dimensions including mold mismatch.

E1

B

14.10 Note 2

0.27

C

–

0.20

3. Lead coplanarity is 0.08 mm maximum.

L

–

0.75

e

0.50 TYP

10/5/2001

TITLE

DRAWING NO. REV.

2325 Orchard Parkway

San Jose, CA 95131

100A, 100-lead, 14 x 14 mm Body Size, 1.0 mm Body Thickness,

0.5 mm Lead Pitch, Thin Profile Plastic Quad Flat Package (TQFP)

100A

C

R

197

1138H–FPSLI–6/05

9.3

144L1 – LQFP

D1

D

XX

e

E1

E

N

b

Bottom View

Top View

COMMON DIMENSIONS

(Unit of Measure = mm)

MIN

0.05

1.35

MAX

0.15

1.45

NOM

NOTE

SYMBOL

A1

A2

D

6

A2

1.40

22.00 BSC

20.00 BSC

22.00 BSC

20.00 BSC

0.50 BSC

0.22

A1

D1

E

2, 3

4, 5

L1

Side View

E1

e

b

0.17

0.27

L1

1.00 REF

1. This drawing is for general information only; refer to JEDEC Drawing MS-026 for additional information.

2. The top package body size may be smaller than the bottom package size by as much as 0.15 mm.

Notes:

3. Dimensions D1 and E1 do not include mold protrusions. Allowable protrusion is 0.25 mm per side. D1 and E1 are maximum plastic

body size dimensions including mold mismatch.

4. Dimension b does not include Dambar protrusion. Allowable Dambar protrusion shall not cause the lead width to exceed the maximum

b dimension by more than 0.08 mm. Dambar cannot be located on the lower radius or the foot. Minimum space between protrusion and

an adjacent lead is 0.07 mm for 0.4 and 0.5 mm pitch packages.

5. These dimensions apply to the flat section of the lead between 0.10 mm and 0.25 mm from the lead tip.

6. A1 is defined as the distance from the seating place to the lowest point on the package body.

11/30/01

TITLE

144L1, 144-lead (20 x 20 x 1.4 mm Body), Low Profile

Plastic Quad Flat Pack (LQFP)

DRAWING NO.

REV.

2325 Orchard Parkway

San Jose, CA 95131

144L1

A

R

198

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

9.4

208Q1 – PQFP

D1

A2

L1

A1

E1

Side View

e

b

Top View

D

COMMON DIMENSIONS

(Unit of Measure = mm)

MIN

0.25

3.20

MAX

0.50

3.60

NOM

–

NOTE

SYMBOL

A1

A2

D

3.40

E

30.60 BSC

28.00 BSC

30.60 BSC

28.00 BSC

0.50 BSC

–

D1

E

2, 3

4

E1

e

b

0.17

0.27

L1

1.30 REF

Bottom View

Notes: 1. This drawing is for general information only; refer to JEDEC Drawing MS-129, Variation FA-1, for proper dimensions, tolerances, datums, etc.

2. The top package body size may be smaller than the bottom package size by as much as 0.15 mm.

3. Dimensions D1 and E1 do not include mold protrusions. Allowable protrusion is 0.25 mm per side. D1 and E1 are maximum plastic

body size dimensions including mold mismatch.

4. Dimension b does not include Dambar protrusion. Allowable Dambar protrusion shall not cause the lead width to exceed the maximum b

dimension by more than 0.08 mm. Dambar cannot be located on the lower radius or the foot. Minimum space between protrusion

and an adjacent lead is 0.07 mm.

03/10/05

TITLE

DRAWING NO.

REV.

2325 Orchard Parkway

San Jose, CA 95131

208Q1, 208-lead (28 x 28 mm Body, 2.6 Form Opt.),

Plastic Quad Flat Pack (PQFP)

208Q1

C

R

199

1138H–FPSLI–6/05

10. Thermal Coefficient Table

Theta J-A

0 LFPM

Theta J-A

225 LFPM

Theta J-A

500 LPFM

Package Style

PLCC

Lead Count

Theta J-C

84

37

47

33

32

30

39

27

28

25

33

23

24

12

22

8.5

10

TQFP

100

144

208

LQFP

PQFP

200

AT94KAL Series FPSLIC

1138H–FPSLI–6/05

AT94KAL Series FPSLIC

Table of Contents

Features..................................................................................................... 1

1 Description .................................................................................................. 2

2 FPGA Core .................................................................................................. 4

2.1 Fast, Flexible and Efficient SRAM .........................................................................4

2.2 Fast, Efficient Array and Vector Multipliers ...........................................................4

2.3 Cache Logic Design ..............................................................................................4

2.4 Automatic Component Generators ........................................................................5

2.5 The Symmetrical Array ..........................................................................................5

2.6 The Busing Network ..............................................................................................6

2.7 Cell Connections ...................................................................................................8

2.8 The Cell .................................................................................................................8

2.9 RAM ....................................................................................................................10

2.10 Clocking and Set/Reset .......................................................................................14

3 FPGA/AVR Interface and System Control .............................................. 21

3.1 FPGA/AVR Interface – Memory-mapped Peripherals .........................................21

3.2 Program and Data SRAM ...................................................................................22

3.3 Data SRAM Access by FPGA – FPGAFrame Mode ...........................................24

3.4 SRAM Access by FPGA/AVR .............................................................................24

3.5 AVR Cache Mode ...............................................................................................29

3.6 Resets .................................................................................................................29

3.7 System Control ....................................................................................................30

4 AVR Core and Peripherals ....................................................................... 34

4.1 Instruction Set Nomenclature (Summary) ...........................................................35

4.2 Complete Instruction Set Summary ....................................................................36

4.3 Pin Descriptions ..................................................................................................40

4.4 Clock Options ......................................................................................................41

4.5 Architectural Overview ........................................................................................43

4.6 General-purpose Register File ............................................................................44

4.7 X-register, Y-register and Z-register ....................................................................45

4.8 ALU – Arithmetic Logic Unit ................................................................................45

4.9 Multiplier Unit ......................................................................................................45

4.10 SRAM Data Memory ...........................................................................................45

4.11 Memory-mapped I/O ...........................................................................................48

i

1138H–FPSLI–2/3/05

4.12 Software Control of System Configuration ..........................................................52

4.13 FPGA Cache Logic .............................................................................................54

4.14 FPGA I/O Selection by AVR ................................................................................55

4.15 FPGA I/O Interrupt Control by AVR ....................................................................59

4.16 Reset and Interrupt Handling ..............................................................................60

4.17 Sleep Modes .......................................................................................................69

4.18 JTAG Interface and On-chip Debug System .......................................................71

4.19 IEEE 1149.1 (JTAG) Boundary-scan ..................................................................76

4.20 Bypass Register ..................................................................................................77

4.21 Device Identification Register ..............................................................................78

4.22 AVR Reset Register ............................................................................................79

4.23 Timer/Counters ...................................................................................................89

4.24 Timer/Counter Prescalers ...................................................................................89

4.25 8-bit Timers/Counters T/C0 and T/C2 .................................................................90

4.26 Timer/Counter1 .................................................................................................101

4.27 Watchdog Timer ................................................................................................110

4.28 Multiplier ............................................................................................................112

4.29 UARTs ...............................................................................................................129

4.30 2-wire Serial Interface (Byte Oriented) ..............................................................140

4.31 I/O Ports ............................................................................................................158

5 AC & DC Timing Characteristics ........................................................... 170

5.1 Absolute Maximum Ratings*⁽¹⁾..........................................................................170

5.2 DC and AC Operating Range – 3.3V Operation ...............................................170

5.3 DC Characteristics – 3.3V Operation – Commercial/Industrial (Preliminary) ....171

6 Power-On Power Supply Requirements ............................................... 172

6.1 FPSLIC Dual-port SRAM Characteristics ..........................................................173

6.2 External Clock Drive Waveforms ......................................................................176

6.3 AC Timing Characteristics – 3.3V Operation ....................................................177

6.4 AC Timing Characteristics – 3.3V Operation ....................................................178

6.5 AC Timing Characteristics – 3.3V Operation ....................................................179

6.6 AC Timing Characteristics – 3.3V Operation ....................................................180

7 Packaging and Pin List Information ..................................................... 181

8 Ordering Information ............................................................................. 195

9 Packaging Information ........................................................................... 196

ii

AT94KAL Series FPSLIC

1138H–FPSLI–2/3/05

AT94KAL Series FPSLIC

9.1 84J – PLCC .......................................................................................................196

9.2 100A – TQFP ....................................................................................................197

9.3 144L1 – LQFP ...................................................................................................198

9.4 208Q1 – PQFP ..................................................................................................199

10 Thermal Coefficient Table ..................................................................... 200

Table of Contents....................................................................................... i

iii

1138H–FPSLI–2/3/05

Atmel Corporation

Atmel Operations

2325 Orchard Parkway

San Jose, CA 95131, USA

Tel: 1(408) 441-0311

Fax: 1(408) 487-2600

Memory

RF/Automotive

Theresienstrasse 2

Postfach 3535

74025 Heilbronn, Germany

Tel: (49) 71-31-67-0

Fax: (49) 71-31-67-2340

2325 Orchard Parkway

San Jose, CA 95131, USA

Tel: 1(408) 441-0311

Fax: 1(408) 436-4314

Regional Headquarters

Microcontrollers

2325 Orchard Parkway

San Jose, CA 95131, USA

Tel: 1(408) 441-0311

Fax: 1(408) 436-4314

1150 East Cheyenne Mtn. Blvd.

Colorado Springs, CO 80906, USA

Tel: 1(719) 576-3300

Europe

Atmel Sarl

Route des Arsenaux 41

Case Postale 80

CH-1705 Fribourg

Switzerland

Tel: (41) 26-426-5555

Fax: (41) 26-426-5500

Fax: 1(719) 540-1759

Biometrics/Imaging/Hi-Rel MPU/

High Speed Converters/RF Datacom

Avenue de Rochepleine

La Chantrerie

BP 70602

44306 Nantes Cedex 3, France

Tel: (33) 2-40-18-18-18

Fax: (33) 2-40-18-19-60

BP 123

38521 Saint-Egreve Cedex, France

Tel: (33) 4-76-58-30-00

Fax: (33) 4-76-58-34-80

Asia

Room 1219

Chinachem Golden Plaza

77 Mody Road Tsimshatsui

East Kowloon

Hong Kong

Tel: (852) 2721-9778

Fax: (852) 2722-1369

ASIC/ASSP/Smart Cards

Zone Industrielle

13106 Rousset Cedex, France

Tel: (33) 4-42-53-60-00

Fax: (33) 4-42-53-60-01

1150 East Cheyenne Mtn. Blvd.

Colorado Springs, CO 80906, USA

Tel: 1(719) 576-3300

Japan

9F, Tonetsu Shinkawa Bldg.

1-24-8 Shinkawa

Chuo-ku, Tokyo 104-0033

Japan

Tel: (81) 3-3523-3551

Fax: (81) 3-3523-7581

Fax: 1(719) 540-1759

Scottish Enterprise Technology Park

Maxwell Building

East Kilbride G75 0QR, Scotland

Tel: (44) 1355-803-000

Fax: (44) 1355-242-743

Literature Requests

www.atmel.com/literature

Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any

intellectual property right is granted by this document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN ATMEL’S TERMS AND CONDI-

TIONS OF SALE LOCATED ON ATMEL’S WEB SITE, ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY

WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR

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intended, authorized, or warranted for use as components in applications intended to support or sustain life.

marks or trademarks of Atmel Corporation or its subsidiaries. Microsoft^®, Windows^®and Windows NT^®are the registered trademarks of

Microsoft Corporation. Other terms and product names may be trademarks of others.

Printed on recycled paper.

1138H–FPSLI–2/3/05


型号：	AT94K10AL-25AJJ
厂家：	ATMEL
描述：	Field Programmable Gate Array, 576 CLBs, 10000 Gates, CMOS, PQCC84, PLASTIC, LCC-84 栅可编程逻辑
文件：	总204页 (文件大小：2975K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

AT94K10AL-25AJJ [ATMEL]

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