这是从互联网搜寻而来的一篇毕业设计论文，作者不知 论文非常完整，就方案讨论到硬件系统设计到软件仿真交待的非常清楚
作为温度风扇控制是一篇非常好的论文
最大的特点，该论文程序代码采用了C51代码，具有很好的可读性，给我们具有很好的参考意义。 在此感谢论文作者付出的辛勤汗水！ 目录正文从第二页开始……
目 录 错误！未定义书签。
摘 要 ······················································································································ I Abstract ·························································································· 错误！未定义书签。 第一章 整体方案设计 ······························································································· 1
1.1 前 言 ·········································································································· 1 1.2 系统整体设计 ······························································································· 1 1.3方案论证 ······································································································· 2
1.3.1 温度传感器的选择 ················································································ 2 1.3.2 控制核心的选择 ··················································································· 3 1.3.3 温度显示器件的选择 ············································································ 3 1.3.4 调速方式的选择 ··················································································· 3
第二章 各单元模块的硬件设计·················································································· 5
2.1系统器件简介 ································································································ 5
2.1.1 DS18B20单线数字温度传感器简介 ························································ 5 2.1.2 达林顿反向驱动器ULN2803简介 ························································· 5 2.1.3 AT89C52单片机简介 ·········································································· 6 2.1.4 LED数码管简介 ················································································· 7 2.2 各部分电路设计 ···························································································· 8
2.2.1 开关复位与晶振电路 ············································································ 9 2.2.2 独立键盘连接电路 ················································································ 9 2.2.3 数码管显示电路 ················································································· 10 2.2.4 温度采集电路 ····················································································· 11 2.2.5 风扇电机驱动与调速电路 ··································································· 12
第三章 软件设计 ···································································································· 14
3.1 程序设置 ···································································································· 14 3.2 用Keil C51编写程序 ·················································································· 14 3.3 用Proteus进行仿真 ····················································································· 15
3.3.1 Proteus简介 ························································································ 15 3.3.2 本设计基于Proteus的仿真 ·································································· 16
第四章 系统调试 ···································································································· 21
4.1 软件调试 ···································································································· 21
4.1.1 按键显示部分的调试 ·········································································· 21 4.1.2 传感器DS18B20温度采集部分调试 ···················································· 21 4.1.3 电动机调速电路部分调试 ··································································· 21 4.2 硬件调试 ···································································································· 22
4.2.1 按键显示部分的调试 ·········································································· 22 4.2.2 传感器DS18B20温度采集部分调试 ···················································· 22 4.2.3 电动机调速电路部分调试 ··································································· 22 4.3 系统功能 ···································································································· 23
4.3.1 系统实现的功能 ················································································· 23 4.3.2 系统功能分析 ····················································································· 23
结 论 ················································································································ 24 参考文献 ················································································································ 25
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致 谢 ················································································································ 26 附录1：电路总图 ··································································································· 27 附录2：程序代码 ··································································································· 28
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基于单片机的温控风扇的设计
摘 要
温控风扇在现代社会中的生产以及人们的日常生活中都有广泛的应用，如工业生产中大型机械散热系统中的风扇、现在笔记本电脑上的广泛应用的智能CPU风扇等。本文设计了基于单片机的温控风扇系统，采用单片机作为控制器，利用温度传感器DS18B20作为温度采集元件，并根据采集到的温度，通过一个达林顿反向驱动器ULN2803驱动风扇电机。根据检测到的温度与系统设定的温度的比较实现风扇电机的自动启动和停止，并能根温度的变化自动改变风扇电机的转速，同时用LED八段数码管显示检测到的温度与设定的温度。
关键词：单片机、DS18B20、温控、风扇
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第一章 整体方案设计
1.1 前 言
在现代社会中，风扇被广泛的应用，发挥着举足轻重的作用，如夏天人们用的散热风扇、工业生产中大型机械中的散热风扇以及现在笔记本电脑上广泛使用的智能CPU风扇等。而随着温度控制技术的发展，为了降低风扇运转时的噪音以及节省能源等，温控风扇越来越受到重视并被广泛的应用。在现阶段，温控风扇的设计已经有了一定的成效，可以使风扇根据环境温度的变化进行自动无级调速，当温度升高到一定时能自动启动风扇，当温度降到一定时能自动停止风扇的转动，实现智能控制。
随着单片机在各个领域的广泛应用，许多用单片机作控制的温度控制系统也应运而生，如基于单片机的温控风扇系统。它使风扇根据环境温度的变化实现自动启停，使风扇转速随着环境温度的变化而变化，实现了风扇的智能控制。它的设计为现代社会人们的生活以及生产带来了诸多便利，在提高人们的生活质量、生产效率的同时还能节省风扇运转所需的能量。
本文设计了由ATMEL公司的8052系列单片机AT89C52作为控制器，采用DALLAS公司的温度传感器DS18B20作为温度采集元件，并通过一个达林顿反向驱动器ULN2803驱动风扇电机的转动。同时使系统检测到得环境温度以及系统预设的温度动态的显示在LED数码管上。根据系统检测到得环境温度与系统预设温度的比较，实现风扇电机的自动启停以及转速的自动调节。
1.2 系统整体设计
本设计的整体思路是：利用温度传感器DS18B20检测环境温度并直接输出数字温度信号给单片机AT89C52进行处理，在LED数码管上显示当前环境温度值以及预设温度值。其中预设温度值只能为整数形式，检测到的当前环境温度可精确到小数点后一位。同时采用PWM脉宽调制方式来改变直流风扇电机的转速。并通过两个按键改变预设温度值，一个提高预设温度，另一个降低预设温度值。系统结构框图如下：
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