说明：  （1） 学习和掌握了解分频电路、通用同步计数器、异步计数器的使用方法； （2） 理解Moore和Mealy两种状态机的一般编程方法，能够按工程控制需求设计相应的逻辑和时序控制程序。 以开发板上的六盏LED小灯模拟，三盏小灯模拟一个方向的红黄绿交通灯灯，用VHDL语言编程实现红绿交通灯控制程序。
((1) to learn and master the understanding of frequency division circuit, universal synchronous counter, asynchronous counter to use (2) to understand Moore and Mealy two state machine of the general programming method, according to engineering control requirements to design the corresponding logic and timing control procedures. To the development of the six small LED lights on the board simulation, three small lights to simulate a direction of the red, yellow and green traffic lights, using VHDL language programming to achieve red and green traffic light control program.)