基于状态机的交通灯控制 交通灯初始状态为红灯，交通灯工作过程依次是红绿黄宏，黄灯3s,红灯9s,绿灯6s。-Traffic light control based on state machine Traffic lights initial state is red, traffic lights work process is followed by red and green yellow macro, yellow 3s, red 9s, green 6s.