交通灯控制系统，东西向绿灯亮若干秒，黄灯闪烁几次后红灯亮，红灯亮后，南北向由红灯变为绿灯，若干秒后南北向黄灯闪烁几次后变红灯，东西向变绿灯，如此重复-Traffic light control system, something the green light for several seconds, the yellow light flashes a few times after the red light after red light, red light into green lig