单片机

河南机电高等专科学校

毕业设计（论文）

基于单片机的恒温箱设计

系 部: 自动控制系

专 业: 计算机控制技术

班 级:

二零一五年三月

摘要

摘 要

本文论述了具有温度设定灵活、数字显示及语音报警等功能的温度控制的设计。该系统主要是由中央控制器、温度检测器、显示器等模块组成。该系统以功能较强的8位89C52单片机为控制核心，温度检测部分采用DS18B20温度传感器，用LED数码管做显示器。温度传感器DS18B20采集温度信号送给单片机，单片机对信号进行相应处理，并把温度数据送LED显示，从而实现对温度控制的目的。由于单片机功能强大，可大大加快系统的开发与调试速度，并具有控制方便、简单、灵活等特点，故可以把数字温度传感器DS18B20做成探头，探入到狭小的地方，增加了实用性。更能串接多个数字温度传感器DS18B20进行多范围的温度检测。

关键字：89C52单片机；温度采集；温度控制

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ABSTRACT

This paper discusses the design of temperature control with temperature set flexible, digital display and voice alarm function. The system is mainly composed of a central controller, temperature detector, the display module. The 8 bit 89C52 microcontroller in the system with strong function as the control core, the temperature detection part adopts the temperature sensor DS18B20, with LED digital tube as display. Temperature sensor DS18B20 collecting temperature signal to the microcontroller, the microcontroller carries on corresponding processing to the signal, and the temperature data to the LED display, so as to achieve the purpose of temperature control. Because the SCM powerful, can greatly accelerate the development and debugging of speed of the system, and has the characteristics of convenient control, simple, flexible, we can put the digital temperature sensor made of DS18B20 probe, probe into the narrow place, increase the practicability. More on temperature detection is connected with a plurality of digital temperature sensor DS18B20 multi range.

Keywords: 89C52 MCU; temperature measurement; temperature control

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目录

第1章 绪论 ............................................................................................................................. 1

1.1 智能恒温箱的发展现状 ................................................................................................ 1

1.2 智能恒温箱研究内容 .................................................................................................... 1

1.3 智能恒温箱的研究意义 ................................................................................................ 2

第2章 智能恒温箱概述 ......................................................................................................... 3

2.1 系统的主要功能 ............................................................................................................ 3

2.2 智能恒温箱的工作流程 ................................................................................................ 4

2.3 恒温箱的工作过程 ........................................................................................................ 6

2.4单片机基础知识 ............................................................................................................. 6

2.4.1 数码管 ..................................................................................................................... 6

2.4.2 定时器中断 ............................................................................................................. 7

2.4.3 独立键盘 ................................................................................................................. 7

第3章 智能恒温箱的硬件设计 ............................................................................................. 9

3.1 硬件电路设计概述 ....................................................................................................... 9

3.2 总体硬件原理 ............................................................................................................... 9

3.3 时钟频率电路设计 ..................................................................................................... 10

3.4 复位电路设计 ............................................................................................................. 11

3.5显示电路设计 .............................................................................................................. 12

3.5.1 显示电路概述 ..................................................................................................... 12

3.5.2 七段LED数码管的原理 ..................................................................................... 13

3.5.3 显示电路整体设计 ............................................................................................. 15

3.6 开关键盘设计 ............................................................................................................. 15

3.6.1 指拨开关 ............................................................................................................. 15

3.6.2 按键开关 ............................................................................................................. 16

3.7 指示灯电路 ................................................................................................................. 16

3.8 温度采集电路 ............................................................................................................. 17

3.8.1 DS18B20的性能 ................................................................................................ 17

3.8.2 DS18B20的管脚排列 ........................................................................................ 18

3.9 本章小结 ..................................................................................................................... 18

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