1.设计一个交通灯控制器。

2.利用学习机上的发光二极管，设定东、南、西、北4个方向，各3个灯（红、黄、绿）。交通灯控制器正常工作时，南北方向红灯亮3秒，黄灯闪2秒，绿灯亮3秒，以此类推。东西方向绿灯亮3秒，黄灯闪2秒，红灯亮3秒，以此类推。

3.设定两个紧急按钮，一个控制南北灯，一个控制东西灯。当按下相应的紧急键时，其控制方向的交通灯亮绿灯，其他方向的交通灯亮红灯，至自控键松开，恢复正常交通控制。

-1. Design of a traffic light controller. 2. Use of learning machine on the LED and set the East, South, West, North 4 direction, the three lights (red, yellow, green). Traffic signal controller normal working hours, the north - and south-bound red light three seconds, two seconds flashing yellow light, green light-three seconds, and so on. East-west direction green three seconds, two seconds flashing yellow light, red light three seconds, and so on. 3. Set two emergency buttons, a north-south control lights, a light control things. When pressing the corresponding key emergency, its control the traffic lights green, the other direction, the traffic lights class. Key to loose control and restore normal traffic control.