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，实现主支路路口的交通信号灯控制（尽可能保持主线的畅通，即在通常情况下，保持主线的放行，只有在支线到达时，才放行支线），同时采用LCD显示倒计时时间及当前灯的状态。-The use of MCU timer timing, so that the crossroads at the traffic lights turn out light and to achieve the main slip road junction traffic lights control (as far as possible the smooth flow of the main line, that is, under normal circumstances, to maintain the release of the main line, and only arrived at the branch only when the release branch), while using LCD display countdown time and the current lighting condition.