基于AT89C51单片机设计制作一个抢答器，具体要求如下：
1、　　设计一个智力竞赛抢答器，可同时共8名选手参加比赛，编号为1、2、3、4、5、6、7、8，各用一个按键。
2、　　用一个按键作为主持人总开关，用来控制系统的清零和抢答的开始。
3、　　抢答器开始后，数码管开始10秒倒计时，若有选手按动抢答按钮，在LED数码管上显示选手的编号，同时灯亮且伴随声音提示；倒计时完成后，选手不能在抢答；有人抢答成功后，要禁止其他选手抢答；最先抢答选手的编号一直保留到主持人将系统清零。(Based on AT89C51 single chip computer, a rush answerer is designed and manufactured. The specific requirements are as follows:
1. Designing an intelligence contest answering machine, which can be attended by 8 competitors at the same time, numbered 1, 2, 3, 4, 5, 6, 7 and 8, each with a button.
2. A key is used as the master switch of the host, which is used to clear the zero of the control system and start the rush response.
3. After the answering machine starts, the digital tube counts down 10 seconds. If a player presses the answering button and displays the player's number on the LED digital tube, the light is on and accompanied by sound prompts. After the countdown is completed, the competitor can't rush to answer. When someone rushes to answer successfully, other competitors are forbidden to rush to answer. The number of the first competitor is kept until the host clears the system.)