基于PT100热电阻温度传感器和AT89C51单片机

摘 要

本课题本系统采用PT100热电阻温度传感器和单片机组成可靠性高、功耗低的温度检测系统。以AT89C51单片机系统为核心，对单点的温度进行实时检测。采用模拟温度传感器PT100对温度进行检测；采用串型模数转换器ADC0809进行A/D转换把温度信号调解转换为电压信号与AT89C51单片机接口设置LED八段数码管实时显示温度值。本设计包括温度传感器、A/D转换模块、数据传输模块、温度显示模块四个部分。

关键词：单片机，PT100热电阻，ADC0809，温度检测

I

The design of Single Chip Microcomputer

Temperature Detection System

Based on the Resistive Thermal Detector of PT100

Abstract

This article AT89C51 monolithic integrated circuit which produces by ATMEL Corporation is the core, can inspect a single point of the temperature in real time. The adoption of the serial A/D for temperature signals into voltage signal mediation AT89C51 Single-Ship Compute interfaces with the eighth LED digital display of real-time temperature. The design includes four parts of the temperature sensor and the A / D converter module and the data transmission modules and the temperature display module. Each part functions and the process was described in the Paper in detail.

Key words：Single-Ship Computer; Resistive Thermal Detector of PT100; ADC0809; Measure-temperature

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重庆科技学院高等教育自学考试本科毕业论文 目录

目 录

摘 要 ...................................................................................................................................... I Abstract .................................................................................................................................... II 1 绪论 .......................................................................................................................................... 1

1.1 课题背景........................................................................................................................... 1 1.2 方案论证........................................................................................................................... 2

1.2.1 单片机选型 ........................................................................................................... 2 1.2.2 模数转换器选型 ................................................................................................... 3 1.2.3 显示方案确定 ....................................................................................................... 3

2 硬件设计 ................................................................................................................................ 4

2.1 温度信号的获取与放大 ................................................................................................... 4

2.1.1 元件介绍 ............................................................................................................... 4 2.1.2 放大电路设计 ....................................................................................................... 4 2.2 模数转换单元 ................................................................................................................... 5

2.2.1 8位串行A/D转换器ADC0809 ............................................................................. 5 2.2.2 模数转换单元电路的设计 ................................................................................... 7 2.3 键盘电路的设计 ............................................................................................................... 8 2.4 LED显示电路的设计........................................................................................................ 8

2.4.1 LED数码管原理 .................................................................................................... 9 2.4.2 LED数码管编码方式 ............................................................................................ 9 2.4.3 LED数码管显示方式和典型应用 ...................................................................... 10 2.4.4 LED数码管的原理图 .......................................................................................... 11 2.5 声光报警电路 ................................................................................................................. 12 2.6 单片机接口电路 ............................................................................................................. 13

2.6.1单片机的时钟电路 .............................................................................................. 13 2.6.2复位电路和复位状态 .......................................................................................... 13

3 软件设计 .............................................................................................................................. 16

3.1 程序设计语言的选用 ..................................................................................................... 16 3.2 软件程序的设计 ............................................................................................................. 16

3.2.1 程序流程 ............................................................................................................. 16 3.2.2 键盘管理 ............................................................................................................. 17 3.2.3 LED显示 .............................................................................................................. 18

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重庆科技学院高等教育自学考试本科毕业论文 目录

3.2.4 模拟量的采集与处理 ......................................................................................... 18 3.3源程序.............................................................................................................................. 22

4 抗干扰设计......................................................................................................................... 29

4.1 用于单片机系统的干扰抑制元件 ................................................................................. 29 4.2 提高单片机系统抗干扰能力的主要手段 ..................................................................... 29

5 结 论 ................................................................................................................................... 31 致 谢 ................................................................................................................................... 32 参考文献....................................................................................................................................33 论文原创性声明 ................................................................................... 错误！未定义书签。

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