说明：  本系统采用MSC-51系列单片机ATSC51和可编程并行I/O接口芯片8255A为中心器件来设计交通灯控制器，实现了能根据实际车流量通过8051芯片的P1口设置红、绿灯燃亮时间的功能；红绿灯循环点亮，倒计时剩5秒时黄灯闪烁警示（交通灯信号通过PA口输出，显示时间直接通过8255的PC口输出至双位数码管）；车辆闯红灯报警；绿灯时间可检测车流量并可通过双位数码管显示。本系统实用性强、操作简单、扩展功能强。
(The system uses MSC-51 Series Microcontroller ATSC51 and programmable parallel I/O interface chip 8255A-centric devices to design traffic signal controller based on the actual traffic flow can be achieved through the P1 port 8051 chip set of red, green, gave the time of function traffic light cycle of light, the countdown 5 seconds left when the yellow light flashing warning (traffic light signal through the PA port output, display time directly through the 8255 output of the PC port to double-digit nixie tube) of vehicles running red lights warning green time can detect vehicles flow can be through a double-digit LED display. The system practical, simple, extending strong function.)