上电后蜂鸣器响一声后开始倒计时，抢答后数码管显示抢答结果，倒计时停止。在40秒内若无任何键按下，蜂鸣器长响，结束，LED开始闪烁-The buzzer sounds after power-start countdown digital display Responder Responder results, the countdown stops. If there is no any key within 40 seconds press, long loud buzzer, ending

一篇文章，介绍绘图方法，使用双缓冲技术实现无闪烁绘图-An article about drawing methods, the use of double buffering technology to achieve flicker free drawing