基本要求：

(1)通过功能切换开关设定为抢答功能，完成4人抢答功能，通过启动按键启动抢答，数码管显示抢答到计时，抢答成功后，到计时停止，蜂鸣器响，抢答成功的键盘对应的指示灯亮。

(2)通过功能切换开关设定为投票功能，完成4人对4候选人投票功能，通过启动按键启动表决，数码管显示投票倒计时， 4个LED指示灯闪烁，计时到零，4个LED指示灯灭，从1到4轮番显示表决结果，第一个数码管显示候选人编号，第二个数码管显示该候选人得票数。

扩展要求：

(1)通过串行口将抢答信息、时间信息和投票信息以英文形式显示。

(2)通过串行口可控制投票和抢答的启动。

(3)通过串行口可设定抢答和投票的倒计时时间。

-Basic requirements:

(1) through the function switch is set to answer in features, answer in complete 4 function keys start by starting the answer in, digital display to answer in time, answer in success, to the timing stop, buzzer, answer in the success of the corresponding keyboard The indicator light.

(2) through the function switch is set to the voting feature, completed 4 of 4 candidates voting feature, through the start button to start the vote, vote countdown digital display, four LED lights flashing, time to zero, 4 LED indication Lamp, turns from 1 to 4 show the results of voting, the first digital control candidate number, the second digital display of the candidate votes.

Extension request:

(1) through the serial port will answer in information, time information and voting information to be displayed in English.

(2) can be controlled through a serial port to vote and answer in the start.

(3) can be set via the serial port of the countdown time to answer in and vot