说明：  基于stc89C51设计一个六路抢答器。其中1个绿色led亮起时开始抢答。6个红色led灯在对应六个抢答按键，按下后led灯亮。若6S内没有按键信息则6个LED灯闪烁。按start按键后绿灯亮开始抢答。
(Based on stc89C51 design a six-way Responder. One of the green leds starts to answer. 6 red led lights correspond to the six answer button, press the led light. If there is no key information in 6S, 6 LED lights flash. Press the start button and the green light will start to answer.)