单片机系统设计--电子定时闹钟

2 系统总体方案及硬件设计..............................................................................................................3

2．1 总体方案............................................................................................................................3

2．2 硬件设计............................................................................................................................4

2.2.2 时钟电路....................................................................................................................5

2.2.3 数码管显示电路........................................................................................................6

3 软件设计..........................................................................................................................................7

3．1 系统软件设计....................................................................................................................7

3．2 键盘服务程序....................................................................................................................7

3．3 LED 的编程思想...............................................................................................................7

4．1 操作过程..........................................................................................................................13

4．2 运行结果图......................................................................................................................14

5 课程设计体会................................................................................................................................16

附 1 定时闹钟源程序代码...............................................................................................................16

附 2 系统总体电路图.......................................................................................................................25