摘 要

数字抢答器由主体电路与扩展电路组成。优先编码电路、锁存器、译码电路将参赛队的输入信号在显示器上输出；用控制电路和主持人开关启动报警电路，以上两部分组成主体电路。通过定时电路和译码电路将秒脉冲产生的信号在显示器上输出实现计时功能，构成扩展电路。经过布线、焊接、调试等工作后数字抢答器成形。单片机体积小价格低，应用方便，稳定可靠。单片机将很多任务交给了软件编程去实现，大大简化了外围硬件电路，使外围电路的实现简单方便。单片机系统的硬件结构给予了抢答系统“身躯”，而单片机的应用程序赋予了其新的“生命”，使其在传统的抢答器面前具有电路简单、成本低、运行可靠等特色。对于抢答器我们大家都知道那是用于选手做抢答题时用的，选手进行抢答，抢到题的选手来回答问题。抢答器不仅考验选手的反应速度同时也要求选手具备足够的知识面和一定的勇气。选手们都站在同一个起跑线上，体现了公平公正的原则。

关键字： 抢答电路 定时电路 报警电路

Abstract

Digital responder from the main circuit and expansion circuit. Priority coding circuit, a lock latch and decoding circuit will be the team's input signal on the display output; an alarm starting circuit with the control circuit and the host switch, the above two parts composed of main circuit. Through the timing circuit and decoding circuit to generate the second pulse signal output on the display to achieve timing function, constitute the extended circuit. After wiring, welding, testing and other work forming digital answering device. The single chip microcomputer has the advantages of low price, convenient application, stable and reliable. SCM will be a lot of tasks to the software programming to achieve, greatly simplifying the peripheral hardware circuit, so that the realization of the peripheral circuit is simple and convenient. The hardware structure