设计交通信号灯控制系统。

1）一路延时60S，一路延时40S，演示时为节省时间，一路延时15S，一路延时10S，两路时间分别用不同的数码管显示；

2）倒数3S时，黄灯闪亮；

3）紧急通行控制，如某一方向现为红灯，通过按键强行切换为绿灯，而另一路改为红灯，延时若干秒(10S)后，恢复原状态(红灯)继续倒数。-Design of traffic signal control system.

1) all the way to delay 60S, all the way to delay 40S, when the demonstration to save time, all the way to delay 15S, all the way to delay 10S, two times were different digital display

2) When the countdown 3S, yellow flashing

3) Emergency access control, such as a certain direction is now red, buttons forcibly switched to green, and the other way to red for the delay of several seconds (10S), the restoration of the original state (red) to continue the countdown.