ATMEGA640 datasheet(429/436 Pages) MICROCHIP

429 / 436 page

ATmega640/V-1280/V-1281/V-2560/V-2561/V [DATASHEET]

2549Q–AVR–02/2014

Table of Contents

Features .................................................................................................... 1

Pin Configurations ................................................................................... 2

Overview ................................................................................................... 5

2.1Block Diagram ...........................................................................................................5

2.2Comparison Between ATmega1281/2561 and ATmega640/1280/2560 ...................7

2.3Pin Descriptions .........................................................................................................7

Resources ............................................................................................... 10

About Code Examples ........................................................................... 10

Data Retention ........................................................................................ 10

Capacitive touch sensing ...................................................................... 10

AVR CPU Core ........................................................................................ 11

7.1Introduction ..............................................................................................................11

7.2Architectural Overview .............................................................................................11

7.3ALU – Arithmetic Logic Unit .....................................................................................12

7.4Status Register ........................................................................................................12

7.5General Purpose Register File ................................................................................13

7.6Stack Pointer ...........................................................................................................15

7.7Instruction Execution Timing ...................................................................................16

7.8Reset and Interrupt Handling ...................................................................................17

AVR Memories ........................................................................................ 20

8.1In-System Reprogrammable Flash Program Memory .............................................20

8.2SRAM Data Memory ................................................................................................20

8.3EEPROM Data Memory ..........................................................................................22

8.4I/O Memory ..............................................................................................................26

External Memory Interface .................................................................... 27

9.1Overview ..................................................................................................................27

9.2Register Description ................................................................................................34

9.3General Purpose registers .......................................................................................36

9.4External Memory registers .......................................................................................36

10 System Clock and Clock Options ......................................................... 39

10.1Overview ................................................................................................................39

10.2Clock Systems and their Distribution .....................................................................39

ATMEGA640 Datasheet(PDF) 429 Page - Microchip Technology