基于单片机的数字温度计设计毕业论文

洛阳理工学院毕业设计（论文）I基于单片机的数字温度计设计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。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。我们采用美国DALLAS半导体公司继DS18B20之后推出的一种改进型智能温度传感器DS18B20作为检测元件，温度范围为-55~125℃，最高分辨率可达0.0625℃。DS18B20可以直接读出北侧温度值，而且采用三线制与单片机相连，减少了外部的硬件电路，具有低成本和易使用的特点。本文介绍一种基于AT89C52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0℃~+100℃，使用LCD模块显示，能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，AT89C52单片机功能和应用。该电路设计新颖、功能强大、结构简单。关键词：温度测量，AT89C52，DS18B20，系统仿真洛阳理工学院毕业设计（论文）IIDesignofDigitalThermometerBasedonSCMABSTRACTIndailylifeandindustrialproductionprocess,oftenusedinthedetectionandcontroloftemperature,temperatureistheproductionprocessandscientificexperimentsingeneralandoneoftheimportantphysicalparameter.Traditionalthermocoupleandtemperaturecomponentsarethesecondresistor.Thethermocoupleandthermalresistancearegenerallymeasuredvoltage,andthenreplacedbythecorrespondingtemperature,thesemethodsarerelativelycomplex,requiringarelativelylargenumberofexternalhardwaresupport.Weusearelativelysimplewaytomeasure.WeusetheUnitedStatesfollowingDALLASSemiconductorDS1820improvedaftertheintroductionofasmarttemperaturesensorDS18B20asthedetectionelement,atemperaturerangeof-55℃~125℃,uptoamaximumresolutionof0.0625℃.DS18B20canbedirectlyreadoutthetemperatureonthenorthside,andthree-wiresystemwithsingle-chipconnectedtoadecreaseoftheexternalhardwarecircuit,withlow-costandeasyuse.Theintroductionofacost-basedAT89C52SCMatemperaturemeasurementcircuits,thecircuitsusedDS18B20high-precisiontemperaturesensor,measuringscope0℃~+100℃,cansetthewarninglimitation,theuseofsevensegmentsLCDthatcanbedisplaythecurrenttemperature.Thepaperfocusesonprovidingasoftwareandhardwaresystemcomponentscircuit,introducedthetheoryofDS18B20,thefunctionsandapplicationsofAT89C52.Thiscircuitdesigninnovative,powerful,canbeexpansionarystrong.KEYWORDS:Temperaturemeasurement，AT89C52，DS18B20，Systemsimulation洛阳理工学院毕业设计（论文）III目录前言................................................................................................1第1章绪论......................................................................................21.1设计背景...............................................................................21.1.1温度计的介绍.............................................................21.1.2温度传感器的发展状况..............................................31.2选题的目的和意义...............................................................41.2.1选题的目的.................................................................41.2.2选题的意义.................................................................4第2章系统概述...............................................................................52.1设计方案的选择...................................................................52.1.1方案一.........................................................................52.1.2方案二.........................................................................62.2系统设计原理.......................................................................6第3章系统硬件的设计...................................................................83.1AT89C52的介绍....................................................................83.2DS18B20的介绍.................................................................113.2.1DS18B20的引脚排列................................................113.2.2DS18B20内部结构....................................................123.2.3DS18B20的测温原理................................................163.2.4DS18B20使用的注意事项........................................173.3数字温度计电路设计.........................................................183.3.1数字温度计原理图...................................................183.3.2时钟电路的设计.......................................................183.3.3复位电路的设计.......................................................193.3.4接口电路的设计.......................................................203.3.5显示电路的设计.......................................................203.3.6报警电路的设计.......................................................23第4章系统软件的设计.................................................................24洛阳理工学院毕业设计（论文）IV4.1软件Proteus与Keil............................................................244.1.1Proteus软件...............................................................244.1.2Keil软件....................................................................274.2系统主程序.........................................................................294.2.1主程序.......................................................................294.2.2DS18B20初始化........................................................304.2.3温度转换命令子程序...............................................304.2.4温度数据的计算处理方法........................................314.3源程序................................................................................31第5章仿真....................................................................................325.1仿真结果.............................................................................32结论...........................................................................