电子秤毕业设计

I摘要随着微电子技术的应用，市场上使用的传统称重工具已经满足不了人们的要求。为了改变传统称重工具在使用上存在的问题，在本设计中将智能化、自动化、人性化用在了电子秤重的控制系统中。本系统主要由单片机来控制，测量物体重量部分由称重传感器及A/D转换器组成，加上显示单元，此电子秤俱备了功能多、性能价格比高、功耗低、系统设计简单、使用方便直观、速度快、测量准确、自动化程度高等特点。本设计以AT89S52单片机为主控芯片，实现电子秤的基本控制功能。在设计系统时，为了更好地采用模块化设计法，分步的设计各个单元功能模块，系统的硬件部分可以分为最小系统、数据采集和人机交互界面三大部分。最小系统部分主要包括AT89S52以及复位电路和晶振电路；数据采集部分由稳重传感器、信号的前级处理和A/D转换部分组成，包括仪表放大器INA122和A/D转换器ADC0804；人机交互界面为键盘输入、点阵式液晶显示和语音报价，主要使用4*4矩阵键盘、1602液晶显示模块和电子秤专用语音芯片SC1010B；软件部分应用单片机C语言进行编程，实现了该设计的全部控制功能。该电子秤可以实现基本的称重功能,可以设置单价，还具有累加和报价功能。整个系统结构简单，使用方便，功能齐全，具有一定的开发价值。关键词：AT89S52，称重传感器，A/D转换器，LCD显示器IIABSTRACTWiththeapplicationofmicro-electronicstechnology,traditionponderationinstrumentusedinmarkethasbeennotsatisfactionwithhunmanrequirementsalready.Inordertomakeupforthetraditionalapparatusshortcoming,weimprovetheapparatus'scontrolsystemwithintelligenceandautomation.Thissystemismainlycontrolledbymicrocontroller,thesectionofheightmeasurementaccomplishbysupersonicsensor,thesectionofweightmeasurementaccomplishbyweightsensorandA/Dtransformer,thisapparatushavemanycharacteristicsuchashavingmorefunction,consumelessenergy,smallandmoveeasily,lowprice,measureprecisely,thespeedisquick,automaticworkwithoutpeopleandsoon.ThisdesignasthecontrollerchipAT89S52SCM,realizethebasicelectronicscalecontrolfunction.Inthedesignofthesystem,inordertobetterthemodulardesignmethod,thedesignofthestepeachunitfunctionmodule,thesystem'shardwarepartscanbedividedintothesmallestsystem,dataacquisitionandman-machineinterfaceofthree.MinimumsystemmainlyincludingpartandresetcircuitAT89S52crystalvibrationcircuit;Dataacquisitioninpartbythesteadysensors,signalprocessingandlevelbeforeA/Dconversionparts,includinginstrumentationamplifierINA122andA/DconverterADC0804;Theman-machineinterfaceforkeyboardinput,Dot-matrixLCDdisplayandvoiceoffer,themainuse4*4matrixkeyboard,1602LCDmoduleandelectronicscalesspecialvoicechipSC1010B;ApplicationsoftwareofsinglechipmicrocomputerCprogramminglanguage,realizethedesignofallcontrolfunction.Theelectronicscalescanrealizethebasicweighingfunction,cansettheprice,Alsohastheaccumulationandofferfunction.Thewholesystemstructureissimple,easytouse,thefunctionisallready,hassomeofthedevelopmentvalue.KEYWORDS:AT89S52，ponderation–sensor，A/Dconverter，LCDDisplayi目录摘要.........................................................................................................................................IABSTRACT..............................................................................................................................II1绪论......................................................................................................................................11.1称重技术和衡器的发展..............................................................................................11.2电子秤的组成..............................................................................................................11.2.1电子秤的基本结构............................................................................................11.2.2电子秤的工作原理............................................................................................21.2.3电子秤的计量性能............................................................................................21.3设计思路....................................................................................................................32系统方案论证与选型..........................................................................................................42.1测量部分......................................................................................................................42.2放大部分......................................................................................................................52.3A/D转换部分...............................................................................................................62.4控制器部分..................................................................................................................82.5显示部分......................................................................................................................82.6键盘部分....................................................................................................................112.7语音部分....................................................................................................................123硬件电路设计....................................................................................................................133.1AT89S52的最小系统电路.........................................................................................133.1.1、单片机芯片AT89S52介绍：.......................................................................133.1.2、单片机管脚说明：........................................................................................133.1.3、AT89S52的最小系统电路构成：................................................................153.2数据采集电路.............................................................................................................163.2.1测量电路及放大电路...........................................