基于单片机的温度测量系统设计

摘 要
 随着时代的进步和发展，单片机技术已经普及到我们生活、工作、科研、各个领域，已经成为一种比较成熟的技术, 本文主要介绍了一个基于AT89C51单片机的测温系统，描述了利用数字温度传感器DS18B20测温系统的过程，对传感器在单片机下的硬件连接，软件编程以及各模块系统流程进行了分析，对各部分的电路也一一进行了介绍,该系统可以方便的实现温度采集和显示，灵敏度高、体积小、功耗低等优点，适合于我们日常生活和工、农业生产中的温度测量，也可以当作温度处理模块嵌入其它系统中，作为其他主系统的辅助扩展。
 本设计运用主从分布式思想，由一台上位机（PC微型计算机），下位机（单片机）多点温度数据采集，组成两级分布式多点温度测量的巡回检测系统。该系统采用 RS-232串行通讯标准，通过上位机（PC）控制下位机（单片机）进行现场温度采集。该测温系统能取得并显示8点的温度数据，可直接应用在一些需要测量温度的场合。
 本设计的多点温度测量系统由单片机、测温电路、报警电路、键盘/显示接口电路、显示模块和键盘接口模块共6个模块组成。本文对以上六个部分的软硬件设计作了详细的阐述，介绍了核心芯片的选型，外围电路的连接，芯片与芯片之间的连接电路，程序设计方法和相应的软件程序。
 本系统结构简单，抗干扰能力强，适合于恶劣环境下进行现场温度测量，有广泛的应用前景
 
 关键字：DS18B20  多点测温  单片机
 
 

Abstract
 With the era of progress and development, SCM technology has spread to our lives, work, research, in various fields, has become a relatively mature technology, introduced a paper-based AT89C51 SCM temperature measurement system, described The use of digital temperature sensors DS18B20 temperature measurement system process, the sensor in the SCM hardware connection, software programming and the modular system processes an analysis of the various parts of the circuit also were introduced on January 1, the system can be Facilitate the realization of acquisition and display temperature, high sensitivity, small size, low power consumption advantages suited to our daily lives and industrial and agricultural production in the temperature measurements, as the temperature processing module can be embedded in other systems, as the other Supporting expansion of the main system.

 This design from the use of the main ideological and distributed by a stage crew (PC micro-computers), the next crew (SCM) multi-point temperature data collection, composed of two multi-point temperature measurement Distributed roving detection system. The system uses RS-232 serial communication standards, through the host computer (PC) under the control of crew (SCM) on-site temperature acquisition. The temperature measurement system to obtain and display eight of temperature data, can be directly applied in a number of occasions the need to measure temperature..
The design of the multi-point temperature measurement system by the microcontroller, temperature measurement circuit, alarm circuits, keyboard / display interface circuits, modules and keyboard interface module total of six modules. In this paper, more than six parts of the hardware and software design a detailed exposition on the Selection of the core chip, the external circuit connections, chip and the connection between the circuit chip, program design methods and the corresponding software programs. [资料来源：http://www.THINK58.com]
The system is simple, strong anti-interference capability, suitable for harsh environments spot temperature measurement．It will have a broad prospect.
 
 Key words :DS18B20 multi-point measurements of temperature  single chip microcomputer [资料来源：THINK58.com]

目 录
第1章 绪 论 1
1.1本课题的研究意义 1
1.2温度测量系统的国内外发展状况 1
1.3 本课题的主要工作和目标 2
第2章 系统方案论证 3
2.1 温度传感器的选择 3
2.2主控制器的选择 5
2.3 系统总体方案 5
第3章 系统硬件设计 7
3.1 CPU的选择 7
3.2电源电路设计 11
3.3 看门狗电路设计 11
3.4 键盘及显示电路设计 12
 3.4.1键盘电路 12
 3.4.2显示电路 13
3.5 报警电路设计 14
3.6　温度检测电路设计 15
 3.6.1单总线技术 15
 3.6.2 DS18B20测温原理 17
 3.6.3 DS18B20构成的单总线温度检测系统 23
3.7串口通讯电路 25
第4章 系统软件设计 27
4.1 概述 27
4.2 主程序方案 27
4.3温度采集与显示方案 28
第5章 结 论 30
参考文献 31
致 谢 33
附 录Ⅰ总体硬件连接图 34

[资料来源：http://think58.com]

附 录Ⅱ 程序清单 35 [资料来源：http://think58.com]

[资料来源：http://think58.com]