毕业论文 基于单片机酒精浓度测试仪.doc

摘 要

2000年以来，随着中国经济的高速发展，人民生活水平的迅速提高，中国逐渐步入“汽车社会”，酒后驾车行为所造成事故越来越多，对社会的影响也越来越大，酒精正在成为越来越凶残的“马路杀手”。据有关资料统计，全世界每年因车祸丧生的人数就超过60万人，留下永久性伤残者在400万以上，一般受伤者则不计其数。在许多国家，车祸已成为第一位意外死亡原因。
此外，因为交通事故造成的经济损失也相当惊人。据事故调查统计，大约50%—60%的车祸与饮酒有关。中国公安部门在2009年8月，在全国各地加强查处酒后驾驶的力度，以减少由酒后驾驶造成的恶性交通事故。要查处就涉及到检测人体内的酒精含量和使用设备来进行检测的问题。
本文研究设计了一种用于公共场所具有检测及超限报警功能的酒精浓度智能测试仪。其设计方案基于89C51单片机，MQ3酒精浓度传感器。系统将传感器输出的4~20mA的标准信号通过以AD0832为核心的A/D转换电路调理后，经由单片机进行数据处理，最后由LCD显示酒精浓度值。文中详细介绍了数据采集子系统、数据处理过程以及数据显示子系统和报警电路的设计方法和过程。系统对于采样地点超出规定的酒精浓度时二极管报警电路提醒监测人员。同时，操作人员对于具体报警点的上限值可以通过单片机编程进行设置。
关键词：酒精浓度传感器（MQ3）；MCU；A/D转换器；软件设计；硬件设计


Abstract

Since 2000, with China's rapid economic development and the rapid increase people's living standard, China has gradually stepped into "car society", drink driving accident caused by more and more impact on society is also growing, Alcohol is becoming more and more brutal "killers." According to statistics, the worldwide number of people killed in road accidents every year on more than 60 million people, left with permanent disability of 400 million or more, usually the injured were numerous. In many countries, traffic accidents have become the first cause of accidental deaths.
In addition, the economic losses caused by the accident is quite amazing. Accident investigation, according to statistics, about 50% -60% of car accidents and alcohol-related. China’s Ministry of Public Security in August 2009, around the country to strengthen efforts to investigate and deal with drink driving, to reduce the drink driving accident caused by the vicious. To investigate the human body involving the detection of alcohol and use of equipment to detect problems.
In this paper, design a public place for the detection and limit alarm functions with an alcohol concentration of intelligent tester. This design,based on STC89C51 microcontroller and MQ3 alcohol concentration sensor. System sensor output 4 ~ 20mA standard signal through AD0832 core A / D converter circuit, after conditioning, data processing by the MCU, the final alcohol concentration value from the LCD display. This paper describes the data acquisition subsystem, data processing and data display subsystem and alarm circuit design methods and processes. System requirements for the sampling sites exceeding the alcohol concentration diode reminder alarm circuit monitors. Meanwhile, the operator specific alarm point for the upper limit set by MCU programming. Alcohol tester will bring a driving signal prior to a safe

Key words:Alcohol concentration sensor (MQ3); STC85C52 MUC; A / D converter; Software design;Hardware design


目 录
引言 1
1. 绪论 2
1.1 酒精浓度检测仪开发背景 2
1.2 酒精浓度检测仪的发展 2
1.3 酒精浓度检测仪设计内容 2
2. 方案器件简介 3
2.1 MCU选择的简介 3
2.2 数模转换器的简介 5
2.3 时钟芯片的简介 7
2.4 液晶显示器的简介 8
3 总体方案设计 9
3.1 STC89C52单片机 9
3.2 ADC0832数模转换 10
3.3 AT24C02存储器 10
3.4 LCD1602液晶显示 10
3.5 编译软件介绍 12
4 硬件设计 13
4.1 最小系统的实现 13
4.2 数据采集设计 15
4.3 A/D转换设计 16
4.4 按键设计 16
4.5 外围扩充存储器电路 17
4.6 时钟芯片电路 18
4.7 LCD1602液晶显示设计 19
4.8 报警设计 21
4.9 电源电路设计 22
5. 软件设计 22
5.1 编译语言的选择 22
5.2 主程序模块 23
5.3 A/D转换模块 23
5.4 按键输入模块 24
5.5 时钟模块 24
5.6 液晶显示输出模块 26
5.7 外围存储模块 27
6. 系统调试 28
6.1 系统硬件调试 28
6.1.1元器件的焊接 28
6.1.2电路测试 28
6.2 系统软件调试 29
6.3 系统整体调试 29
7. 结束语 29
谢 辞 31
参考文献 32
附 录 33
附录一 硬件设计仿真图 33
附录二 硬件设计原理图和PCB图 34
附录三 检测程序 35