ATmega644

目录

产品特点..................................................................................................... 1

1

引脚配置................................................ ................................... 2

1.1Disclaimer ..................................................................................................................3

2

概述................................................. .................................................. 3

2.1Block图...........................................................................................................3

2.2Pin说明........................................................................................................4

3

4

5

资源................................................. ................................................ 7

代码例子............................................... .............................. 8

AVR CPU内核

.......................................................................................... 9

5.1Introduction ................................................................................................................9

5.2Architectural概述............................................... ............................................... 9

5.3ALU - 算术逻辑单元............................................ ........................................ 10

5.4Status注册........................................................................................................11

5.5General通用寄存器文件............................................. ................................... 12

5.6Stack指针...........................................................................................................13

5.7Instruction执行时序.............................................. ..................................... 14

5.8Reset和中断处理............................................. ..................................... 14

6

AVR回忆................................................ ........................................ 18

6.1In系统内可编程闪存程序存储器.......................................... ... 18

6.2SRAM数据存储器.............................................. ................................................. 19

6.3EEPROM数据存储器.............................................. ............................................ 20

6.4I / O存储器..............................................................................................................26

7

系统时钟及时钟选项............................................. ............ 28

7.1Clock系统及其分布............................................ ........................... 28

7.2Clock来源.........................................................................................................29

7.3Low电晶体振荡器............................................. ...................................... 31

7.4Full振幅晶振............................................. ....................................... 32

7.5Low频率晶体振荡器............................................. ............................... 33

7.6Calibrated内部RC振荡器............................................. ................................ 34

7.7128 kHz内部振荡器.............................................. ........................................ 35

7.8External时钟.........................................................................................................36

7.9Clock输出缓冲器.............................................. .................................................. 0.37

i

2593L–AVR–02/07