基于51的抢答器设计源码.其中主持人操控S7与S8两个按键。选手共六位，分别操控S1 S6中的一个按键。当主持人按下抢答开始按键S7后，倒计时开始，计时5s。此后最先按下按键的选手号码将显示与数码管上。后来按下的将无显示。-Based Responder source design (51). S7 and S8 which hosts two control buttons. A total of six players were manipulating S1- S6 of a button. When the host began to press the buzzer button S7, the countdown starts, time 5s. After that first press the button and the player number will be displayed on digital tube. Later pressed will not be displayed.