目录

1

引脚配置................................................ ................................... 3

1.1

放弃............................................................................................................4

2

概述................................................. .................................................. 4

2.1

2.2

框图......................................................................................................5

引脚说明................................................ .................................................. 0.6

3

4

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

AVR CPU内核

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

4.1

4.2

4.3

4.4

4.5

4.6

4.7

4.8

介绍..........................................................................................................9

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

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

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

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

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

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

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

5

AVR AT90USB64 / 128记忆............................................. .............. 18

5.1

5.2

5.3

5.4

5.5

系统内可编程的Flash程序存储器....................................... 18

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

EEPROM数据存储器............................................... ...................................... 22

I / O存储器........................................................................................................28

外部存储器接口............................................... .................................. 29

6

系统时钟及时钟选项............................................. ............ 38

6.1

6.2

6.3

6.4

6.5

6.6

6.7

6.8

6.9

时钟系统及其分布............................................. .................... 38

时钟源....................................................................................................39

低功耗晶振.............................................. ............................... 40

低频晶体振荡器.............................................. ........................ 43

校准的内部RC振荡器.............................................. ......................... 43

128 kHz内部振荡器.............................................. ................................... 45

外部时钟....................................................................................................46

时钟输出缓冲器............................................... ............................................. 47

定时器/计数器振荡器.............................................. ...................................... 47

6.10系统时钟预分频器.............................................. ....................................... 47

6.11 PLL .....................................................................................................................49

1

AT90USB64/128

7593A–AVR–02/06