3.6 CPU States...................................................................................................................... 56
3.6.1程序执行状态............................................ ........................................ 57
3.6.2异常处理国家........................................... ....................................... 57
3.6.3掉电状态........................................... .................................................. 58
3.7访问时序和总线周期............................................ ............................................. 58
3.7.1访问片上存储器( RAM和ROM ) .................................... .............. 58
3.7.2访问片上寄存器域和外部设备................................... 60
第4章异常处理............................................. ........................... 63
4.1概述........................................................................................................................ 63
4.2 Reset............................................................................................................................... 63
4.2.1概述........................................................................................................... 63
4.2.2复位顺序............................................. .................................................. ... 63
4.2.3禁止中断复位后.......................................... ............................ 66
4.3中断........................................................................................................................ 66
4.3.1概述........................................................................................................... 66
4.3.2中断相关的寄存器........................................... ..................................... 67
4.3.3外部中断............................................. ................................................ 70
4.3.4内部中断............................................. ................................................. 71
4.3.5中断处理............................................. ................................................ 72
4.3.6中断响应时间............................................ ........................................ 77
4.4注意事项栈处理............................................. .................................................. ... 77
第5章I / O端口........................................... .............................................. 79
5.1概述........................................................................................................................ 79
5.2端口1 .............................................................................................................................. 80
口数据方向寄存器( P1DDR ) -H'FFB0 ...................................... ............... 81
5.3端口2 .............................................................................................................................. 83
5.4端口3 .............................................................................................................................. 86
5.5端口4 .............................................................................................................................. 89
5.6端口5 .............................................................................................................................. 96
5.7端口6 .............................................................................................................................. 101
5.8端口7 .............................................................................................................................. 106
第6章并行握手接口............................................ ............ 115
6.1概述........................................................................................................................ 115
6.1.1产品特点............................................................................................................. 115
6.1.2座Diagram................................................................................................... 116
6.1.3输入和输出引脚........................................... ............................................. 117
6.2寄存器描述...................................................................................................... 117
6.2.1端口3的数据方向寄存器( P3DDR ) ....................................... ..................... 117
6.2.2端口3数据寄存器( P3DR ) ........................................ ...................................... 118
6.2.3握手控制/状态寄存器( HCSR ) ....................................... ................ 118
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