说明：  本系统由单片机系统、LED 显示、交通灯演示系统组成。以单片机8051为中心器件来设计交通灯控制器，实现了通过P2口使红绿灯循环点亮 ，倒计时剩5秒时黄灯闪烁警示，通过P3口在LED数码显示管显示倒计时，本系统可靠性强、操作简单。
(The system consists of single-chip system, LED display, traffic light demonstration system. As the center of the device to the microcontroller 8051 to design traffic signal controller, to achieve a circulation through the P2 port so that traffic lights light up, the countdown 5 seconds left flashing yellow warning, by P3 the mouth tube in the LED digital display shows the countdown, the system reliability easy to operate.)