目录

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

1

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

1.1引脚说明.......................................................................................................3

2

概述................................................. ..................................................五

2.1框图..........................................................................................................5

之间的ATmega48 ， ATmega88的，与ATmega168 ............................ 6 2.2对比

3

4

5

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

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

AVR CPU内核

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

5.1概述..................................................................................................................9

5.2结构概述............................................... .............................................. 9

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

5.4状态寄存器.......................................................................................................11

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

5.6堆栈指针..........................................................................................................13

5.7指令执行时间.............................................. .................................... 14

5.8复位和中断处理............................................. .................................... 15

6

AVR回忆................................................ ........................................ 17

6.1概述................................................................................................................17

6.2在系统内可编程闪存程序存储器.......................................... ..17

6.3 SRAM数据存储器.............................................. ................................................ 19

6.4 EEPROM数据存储器.............................................. ........................................... 20

6.5 I / O存储器.............................................................................................................21

6.6寄存器说明............................................... ................................................ 22

7

系统时钟及时钟选项............................................. ............ 27

7.1时钟系统及其分布............................................ .......................... 27

7.2时钟源........................................................................................................28

7.3低功耗晶振............................................. ..................................... 29

7.4满振幅晶振............................................. ...................................... 31

7.5低频晶体振荡器............................................. .............................. 33

7.6标定的片内RC振荡器............................................. ............................... 33

7.7 128 kHz内部振荡器............................................. ........................................ 34

i

2545J–AVR–12/06