抢答器的两个按键一个是设置清除键一个是开始键，按照抢答流程，可以实现简易8路抢答功能 （哈工大单片机大作业内附proteus原理图）-Two keys Responder is to set a clear key is a start key, in accordance with the the Responder process can be simple 8-way Responder (HIT SCM operations included proteus schematic)