单片机课程设计报告
题 目： 基于单片机的数字温
度计设计 教 学 系：
***
年 级、专 业： 2010级电子科学和技 术（1）班 姓 名 学 号：
*** *** ***
指 导 教 师： ***
完 成 时 间： 2012年6月 基于单片机的数字温度计设计
作者：*** 指导老师： ***
（年级专业：2010级电子科学和技术一班）
摘 要：本文介绍一种基于AT89S52单片机的一种温度测量及报警电路,该电路采用
DS18B20作为温度监测元件，测量范围-55℃-～+125℃，使用4位LED模块显示，能通过键盘设置温度报警上下限。正文着重给出了软硬件系统的各部分电路，介绍了集成温度传感器DS18B20的原理，AT89S52单片机功能和使用。该电路设计新颖、功能强大、结构简单。
关键词：温度测量 DS18B20 AT89S52
Abstract : The introduction of a cost-based AT89S52 MCU a temperatur measurement circuits,
the circuits used DS18B20 high-precision temperatur sensor , measuring scope -55℃-～
单片机课程设计报告
+125℃,can use the keybord set the warning limitation, the use of four bits seven segments LED that can be display the current temperature. The paper focuses on providing a software and hardware system components circuit, introduced the theory of DS18B20, the founctions and applications of AT89S52 .This circuit design innovative, powerful, can be expansionary strong.
Key Words : Temperatur measurement DS18B20 AT89S52
目 录
1前言······························································3 2方案设计··························································3 3 系统的硬件设计····················································4 3.1 主控制器························································4 3.2 显示电路························································5 3.3 温度传感器工作原理··············································6 3.4 温度传感器接口电路··············································9 4 系统的软件设计····················································9 4.1 主程序··························································9 4.2 温度测量························································9 4.2.1 初始化DS18B20················································9 4.2.2 等待应答信号·················································10 4.2.3 DS18B20读字节···············································10 4.2.4 DS18B20写字节················································11 4.2.5 启动温度测量·················································12 4.2.6 读取测量结果·················································13 4.2.7各算法流程图·················································14 4.3 数码管显示·····················································15 5 系统的测试和总结·················································16 5.1 测试时的图片···················································16 5.2总结···························································17 参考文献···························································18 致谢词·····························································19
1
单片机课程设计报告
附录1原理图·······················································20 附录2源程序清单···················································20
1 前言
数字温度计（Digital Thermometer）简称DTM，它是采用数字化测量技术，把连续的温度值转换成不连续、离散的数字形式并加以显示的仪表。传统的温度计功能单一、精度低，不能满足数字化时代的需求，采用单片机的数字温度计，由于精度高、抗干扰能力强，可扩展性强、集成方便得到了广泛的使用。温度是许多监控系统中的一个重要参数。DS18B20直接把温度信息转换成相应的数字信号。数据采集、处理模块主要由AT89S52单片机构成，完成温度数据的读取和显示。
本文将介绍智能集成温度传感器DS18B20的结构特征及控制方法，并对AT89S52单片机为控制器构成的数字温度测量装置的工作原理及程序设计作了详细的介绍。该设计控制器使用ATMEL公司的AT89S52单片机，测温传感器使用DALLAS公司DS18B20，用数码管来实现温度显示。
2方案设计
本设计主要是介绍了单片机控制下的温度检测系统，详细介绍了其硬件和软件设计，并对其各功能模块做了详细介绍，其主要功能和指标如下：
? 利用温度传感器（DS18B20）测量某一点环境温度 ? 测量范围为-55℃～＋125℃，精度为±0.5℃ ? 用数码管进行实际温度值显示
采用AT89S52单片机P3 .5口控制温度传感器DS18B20的温度测量，以四位数码感形式输出测量温度，原理图如下图2.1所示：
2