基于C51单片机的跑表程序，用数码管显示，有三个功能按键，按下第一个时时间停止，按下第二个按键时，时间接着跑，按下第三个按键时，时间清零。-Based on C51 PaoBiao of procedures, the use of digital pipe display, have three function keys, according to the first time when stop, punch the two button, time and then run, punch the three button, time reset.