单片机抢答器毕业论文.doc

单片机抢答器毕业论文


摘  要

随着科学技术的不断发展，促使人们学科学、学技术、学知识的手段多种多样。抢答器作为一种工具，已广泛应用于各种智力和知识竞赛场合。但抢答器的使用频率较低，且有的要么制作复杂，要么可靠性低，减少兴致。做为一个单位若专购一台抢答器虽然在经济上可以承受，但每年使用的次数极少，往往因长期存放使（电子器件的）抢答器损坏，再购置的麻烦和及时性就会影响活动的开展,因此设计了本抢答器。
本设计是以六路抢答为基本理念。考虑到依需设定限时回答的功能，利用AT89C51单片机及外围接口实现的抢答系统，利用单片机的定时器/计数器定时和记数的原理，将软、硬件有机地结合起来，使得系统能够正确地进行计时，同时使数码管能够正确地显示时间。用开关做键盘输出，扬声器发生提示。同时系统能够实现：在抢答中，只有开始后抢答才有效，如果在开始抢答前抢答为无效；抢答限定时间和回答问题的时间可在1-99s设定；可以显示是哪位选手有效抢答和无效抢答，正确按键后有音乐提示；抢答时间和回答问题时间倒记时显示，满时后系统计时自动复位及主控强制复位；按键锁定，在有效状态下，按键无效非法。

关键词： AT89C51； LED数码管； 抢答器； 计时； 报警

ABSTRACT

With the continuous development of science and technology, promote learning science, science and technology, knowledge of the variety of means. With a tool for Qiangda, which has been widely used in all kinds of intelligence and knowledge contests occasions. But Qiangda is used for lower frequency, and some production complex or low reliability, and reduced interest. As a unit, if the purchase is a Qiangda .Although the economy can bear, each year the number is extremely small, because of the long-term storage (electronic devices) Qiangda for damage to the purchase of the trouble and timeliness of activities, The development will be affected, so this Qiangda is designed .
This design is six road Qiangda as the basic concept.By taking into account the need for seting time and limiting to answer the function, which uses AT89C51 microcontroller and external interface of Qiangda system, and uses SCM timer / counter timing and the number of mind Principle, the software and hardware organically combined, which could allow the right to conduct time, while the digital display to the correct time. Switching with the keyboard output, speakers in tips. At the same time, system can be realized .In Qiang da and which only begins after the Qiangda only effective, if at the beginning of Qiangda before Qiangda invalid; Qiangda limited time to answer questions and the time can be set in the 1-99 s; players who can show that it is effective and Qiangda Qiang da invalid, right after the music keys tips; Qiangda time to time and answer questions Dao Ji shi, over time, the system automatically reset control and mandatory reduction; keys locked in an active state, the key is invalid illegal.

Key words: AT89C51; alphanumeric display; Qiangda; time; alarm

目    录

摘 要 Ⅰ
ABSTRACT Ⅱ
1 绪 论 1
1.1 课题研究的相关背景 1
1.2 选题的目的和意义 1
1.3 课题研究的内容 2
1.4 国内外研究现状 3
1.5 抢答器目前存在的主要问题 3
2 抢答器的系统概述 4
2.1 系统的主要功能 4
2.2 系统需求分析 5
2.3 抢答器的工作流程 5
2.4 抢答器的工作过程 7
2.5 器件选型方案及详细清单 7
2.6 AT89C51特殊功能寄存器 7
2.7 AT89C51的功能及简介 8
2.7.1 89系列单片机的概况 8
2.7.2 AT89C51单片机的内部结构图 10
2.7.3 各类型单片机的比较分析 11
2.7.4 AT89C51单片机 12
2.8 抢答器的优点及组成 13
2.9 本章小结 13
3 系统总体方案的设计 15
3.1 硬件电路的设计 15
3.2 总体原理图 16
3.3 时钟频率电路的设计 17
3.4 复位电路的设计 17
3.5 显示电路的设计 18
3.5.1 显示模块在系统软件中的安排 18
3.6 键盘扫描电路的设计 21
3.6.1 键盘抖动的软件处理 22
3.7 发声 22
3.8 系统复位 22
3.9 本章小结 25
4 软件设计 26
4.1 主程序系统结构图 26
4.2 软件任务分析 26
4.3 程序流程图 27
4.4 主要程序分析 27
4.5 本章小结 37
5 PROTEUS仿真 38
5.1系统仿真图 38
5.2本章小结 40
6 总结与展望 41
6.1 总结 41
6.2 展望 41
致谢 43
参考文献 44