一、设计要求：交通信号灯模拟控制系统设计利用单片机的定时器定时，令十字路口的红绿灯交替点亮和熄灭，并且用LED数码管显示时间。用8051做输出口，控制十二个发光二极管燃灭，模拟交通灯管理。



二、设计内容：因为本课程设计是交通灯的控制设计，所以要了解实际交通灯的变化情况和规律。假设一个十字路口为东西南北走向。初始状态0为东西红灯，南北红灯。然后转状态1东西红灯，南北绿灯通车，。过一段时间转状态2南北绿灯灭，黄灯亮5秒，东西仍然红灯。再转状态3，东西绿灯通车，南北红灯。过一段时间转状态4，东西绿灯灭，黄灯亮5秒，南北仍然红灯。最后循环至状态1。

　　注意：.双色LED是由一个红色LED管芯和一个绿色LED管芯封装在一起，公用负端。当红色正端加高电平，绿色正端加低电平时，红灯亮；红色正端加低电平，绿色正端加高电平时，绿灯亮；两端都加高电平时，黄灯亮。-First, the design requirements: traffic light control system using single chip analog timer timing, so that the traffic light intersection

Alternating light and off, and LED digital display with time. To do with the 8051 output, control, burning off a dozen light-emitting diodes,

Simulated traffic light management.



Second, the design of content: This course is designed for the control of traffic light design, so to understand the actual changes in traffic lights and rules

Law. Assuming a crossroads for the north-south thing. What the initial state 0 is red, north and south light. Then things turn state 1

Red, green north-south traffic. Over time, turn off State 2 South Green, yellow light for 5 seconds, things are still red. Sub-state

State 3, the opening of something green, north and south light. Switch to state 4 over time, things off the green, yellow light for 5 seconds, north and south are still red

Lights. The last cycle to the state 1.

Note:. Two-color LED is a red LED