学校拟在校园中繁忙的学术路（A）和文化路（C）的十字路口安装交通灯，并有探测器TA和TC。当按下复位键RST时，学术路上绿灯亮，文化路上红灯亮。每隔5秒，控制器检查学术路传感器的输出，若学术路上有人，灯不改变，若学术路上有人，则灯变为黄灯，保持5秒，然后变成红灯亮，同时文化路上辨别绿灯亮。在这个状态下，每隔5秒，控制器检查文化路上是否有人，若有人，保持绿灯亮，若没人，则此路变为黄灯，保持5秒，然后变成红灯亮。状态机周期为5秒的时钟信号-School campus to be in a busy academic path (A) and cultural route (C) the installation of traffic lights at the crossroads, and a detector TA and TC. When you press the reset button RST, academic road the green light, red light on the road culture. Every five seconds, the controller checks the output of the sensor academic way, if someone academic way, the light does not change, if someone academic way, the light turns yellow, 5 seconds, and then a red light, and the way to distinguish culture green light. In this state, every 5 seconds, the controller checks whether the way culture was, if anyone, to keep the green light, if no one, this road becomes yellow, 5 seconds, and then a red light. Period of 5 seconds the state machine clock signal