单片机交通灯的程序，本系统采用单片机AT80C51为中心器件来设计交通灯控制器，系统实用性强、操作简单、扩展性强。本设计就是采用单片机模拟十字路*通灯的各种状态显示以及倒计时时间。
由单片机I/O口扩展系统、交通灯状态显示系统、LED数码显示系统、复位电路等几大部分组成。系统除基本的交通灯功能外，还具有倒计时等功能，较好的模拟实现了十字路口可能出现的状况。(SCM traffic lights program, the system uses microcontroller AT80C51 as the central device to design traffic lights controller, the system is practical, simple operation and strong expansion. This design is to use single chip computer to simulate various state display of traffic lights at crossroads and time of countdown.
It is composed of the I/O port expansion system, the traffic light state display system, the LED digital display system, the reset circuit and so on. Besides the basic function of traffic light, the system also has the function of countdown and so on. It is a good simulation to realize the possible situation of the intersection.)