I摘要本文设计了一种以51单片机来进行控制的电子秤系统，系统的电路部分由以下几个电路模块组成：数据采集和数据处理电路、模数转换电路、LED及蜂鸣器报警电路、最小系统电路、液晶显示电路、矩阵按键电路等。接通电源后，单片机会把压力传感器输入的小信号进行放大处理及模数转换，通过按键设置单价在LCD1602上显示物体总价信息。对于硬件设计部分，我们本着低成本，高效率，系统稳定可行的指导方针选取了一些实用的元器件进行设计。而软件设计则采用模块化的设计方法，争取把软件设计得方便可读易操作。文中还详细分析了应变式压力传感器在重量测量上的应用及其使用的原理，而HX711作为一个高精度的24位A/D转换器如何在模数转换的过程如何运作也有相应的介绍。当然，这次设计的结果能够得到预期的效果也离不开其他各部分电路的相辅相成，我们也对一些配合电路做了简单介绍。仿真部分则为我们的设计是否合理进行了初步验证。最后，我们完成了实际电路的焊接，使得理论有了实物作为支撑，整个设计能够正常实现功能。关键词：51单片机；电子称；压力传感器；模数转换；模块化设计IIABSTRACTThepaperintroduceakindofelectronicweighingsystemwhichbasedonSingle-chipMicrocomputer.Atthebeginning,somebasicmethodsaboutMCUliketheinternalconfiguration,workingprincipleandhowtoprogramareintroduced.Then,howtomeasureanobjectusingastraintypepressuretransducerisintroduced.Severalcircuitmodulesarecontainedinthedesignsuchasdataacquisitionanddataprocessingcircuit,analogtodigitalconversioncircuit,LEDandbuzzeralarmcircuit,minimumsystemcircuit,LCDdisplaymodule,matrixkeyboardcircuit,etc.Whenpressingthebutton,thedetectionisbegun.theweakanalogsignalcomingfromthesensorwillbeamplifiedandconvertedintodigitalsignal.Finally,theprocessedsignalswillbetransmittedtothemicrocomputer.thepriceissetbypressingdifferentbuttonsandtotalpricewillbeshownontheLCD1602.Thehardwareisdesignedtobestable,feasibleandinexpensive,whichwillmakethedesignbettertobeaccepted.Thesoftwareusesmodulardesign.TheprincipleandadvantagesoftheapplicationofthestraingaugepressuresensortotheweightmeasurementandtheapplicationofHX711totheanalogtodigitalconversionareanalyzedindetail.Thecompositionandworkingcharacteristicsofothercircuitsaredescribedaswell.Thefeasibilityofthecircuitisverifiedbysimulation.Finally,thedesignofthephysicalcircuitiscompleted,whichmakestheexpectedresultsoftheprojectberealized.Keywords:51singlechipmicrocomputer;electronicscale；strainpressuresensor;ADconversion;modulardesign;.III目录1引言..............................................................................11.1课题研究的意义....................................................................11.2电子秤的发展现状................................................................11.3设计内容和章节安排.............................................................22单片机简介......................................................................32.1单片机内部结构....................................................................32.2单片机特点及引脚介绍..........................................................52.3单片机中断系统....................................................................72.4单片机最小系统....................................................................82.5编程语言.............................................................................92.5.1汇编语言...........................................................................92.5.2C51语言...........................................................................93单片机外围电路介...
