基于温度传感器的数字温度计

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摘要

在日常生活及工业生产过程中，经常要用到温度的检测及控制，温度是生产过程和科学实验中普遍而且重要的物理参数之一。在生产过程中，为了高效地进行生产，必须对它的主要参数，如温度、压力、流量等进行有效的控制。温度控制在生产过程中占有相当大的比例。温度测量是温度控制的基础，技术已经比较成熟。传统的测温元件有热电偶和二电阻。而热电偶和热电阻测出的一般都是电压，再转换成对应的温度，这些方法相对比较复杂，需要比较多的外部硬件支持。我们用一种相对比较简单的方式来测量。

基于AT89C51单片机作为控制器、使用数字温度传感器DS18B20作为温度采集器的数字温度计。重点阐述了AT89C51的结构性能和引脚功能，DS18B20的性能结构、工作原理和控制方法，以及单片机AT89C51和数字温度传感器DS18B20之间的接口、数据传递。该数字温度计能够测出-20～﹢70℃之间的温度，适合日常生活、工业生产和科学研究等领域对温度测量的需要。

目录

摘要 ...................................................................................................................... 2 1绪论 ................................................................................................................... 4

1.1选题背景及研究意义 ························································································· 4 1.2 温度测量的意义 ······························································································ 4 1.3 系统预期目标 ································································································· 4

2 开发工具Proteus与Keil ............................................................................. 5

2.1 Proteus软件简单应用 ······················································································ 5 2.2 Keil软件调试应用 ·························································································· 5

3 系统设计概述 .................................................................................................. 6

3.1 方案确定 ······································································································· 6 3.2 系统设计原理 ································································································· 6 3.3 系统组成框图 ································································································· 6

4 元器件介绍 ...................................................................................................... 7

4.1 AT89C51单片机介绍 ························································································· 7

4.1.1 AT89C51单片机主要特性 ·········································································· 8 4.1.2 AT89C51单片机管脚 ················································································ 8 4.2 1602LCD 液晶模块简介 ····················································································· 9 4.3 DS18B20介绍 ·································································································· 9

4.3.1 DS18B20内部结构及功能 ········································································ 10 4.3.2 测温原理 ···························································································· 10

5 系统硬件设计 ................................................................................................ 11

5.1主板电路 ······································································································ 11 5.2液晶显示部分与89C51的接口电路 ····································································· 11 5.3 DS18B20温度传感器与单片机的接口电路 ···························································· 12

6 系统软件设计 ................................................................................................ 13

6.1 主程序设计 ·································································································· 13 6.2 DS18B20初始化 ····························································································· 13 6.3 读出温度子程序 ···························································································· 14 6.4 温度转换命令子程序 ······················································································ 14 6.5 计算温度子程序 ···························································································· 15 6.6显示数据刷新子程序 ······················································································· 15

7 系统仿真测试 ................................................................................................ 15 结束语 ................................................................................ 错误！未定义书签。 参考文献 ............................................................................................................ 17 附录1 系统整体电路 ..................................................................................... 18 附录2 实物图 ................................................................................................. 19 附录3 元件清单（名称、型号、数量） ..................................................... 19 附录4 全部程序清单 ..................................................................................... 20

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