基于单片机温度监测系统设计方案外文翻译

精选优质文档-----倾情为你奉上精选优质文档-----倾情为你奉上专心---专注---专业专心---专注---专业精选优质文档-----倾情为你奉上专心---专注---专业基于单片机温度监测系统设计的外文翻译第1页外文文献资料DistributedTemperatureSensor1.Sensorintroduction1.1TemperaturesensorbackgroundInthehumanlivingenvironment,temperatureplayinganextremelyimportantrole。Nomatterwhereyou文档来自于网络搜索live,engagedinanywork,ever-presentdealtwithtemperatureunder.Sincethe18thcentury,industry文档来自于网络搜索sincetheindustrialrevolutiontowhethercanmastersendexhibitionhastheabsolutetemperaturetouch.文档来自于网络搜索Inmetallurgy,steel,petrochemical,cement,glass,medicineindustryandsoon,cansayalmosteighty文档来自于网络搜索percentofindustrialdepartmentshavetoconsiderthefactorswithtemperature.Temperatureforindustrial文档来自于网络搜索soimportant,thuspromotingthedevelopmentofthetemperaturesensor.1.2TemperaturesensordevelopmentMajorgeneralthroughthreesensordevelopmentphase:analogintegratedtemperaturesensor.The文档来自于网络搜索sensoristakenwithsiliconsemiconductorintegratedworkmanship,thereforealsocalledsiliconsensoror文档来自于网络搜索monolithicintegratedtemperaturesensor.Suchsensinginstrumentshavesinglefunction(onlymeasuring文档来自于网络搜索temperature),temperaturemeasurementerrorissmaller,pricelow,fastresponse,thetransmission文档来自于网络搜索distance,smallvolume,micro-consumptionelectronicetc,suitableforlongdistancemeasurement文档来自于网络搜索temperature,temperaturecontrol,donotneedtoundertakenonlinearcalibration,peripheralcircuitis文档来自于网络搜索simple.Itiscurrentlythemostcommonapplicationathomeandabroad,anintegratedsensor。Typical文档来自于网络搜索productshaveAD590AD592,TMP17,LM135,etc.jAnalogintegratedtemperaturecontroller.Analog文档来自于网络搜索integratedtemperaturecontrollermainlyincludetemperaturecontrolswitch,programmabletemperature文档来自于网络搜索controller,atypicalproducthaveLM56,AD22105andMAX6509.Someincreasestrengthtypeintegrated文档来自于网络搜索temperaturecontroller(forexampleTC652/653)alsocontainstheA/Dconverterandcuregoodsequence,文档来自于网络搜索thisprocesswiththeintelligenttemperaturesensorsomesimilarities.Butitisnotitssystem,workbymicro文档来自于网络搜索processingdevicecontrol,thisisthemaindifferencebetween.Ielligent文档来自于网络搜索temperaturesensor(alsocalleddigitaltemperaturedegreessensor)isinthemid1990slaunch.Itis文档来自于网络搜索microelectronicstechnology,computertechnologyandthedynamictestingtechnology(ATE)crystallization.文档来自于网络搜索Intelligenttemperaturesensorinternalcontaintemperaturesensor,A/Dconverter,signalprocessor,第2页memory(orregisters)andinterfacecircuit.Someproductsstilltakemultiplexer,centralcontrolsystem文档来自于网络搜索device(CPU),randomaccessmemory(RAM)andreadonlymemory(ROM).Intelligenttemperaturesensor文档来自于网络搜索ischaracteristicoftemperaturedataandrelevantcanoutputthetemperaturecontrolofthequantity,文档来自于网络搜索adaptationvariousmicrocontroller(MCU);1.3SinglepointandmoretemperaturesensorThedevelopmenttrendofthetemperaturesensor.Inthe21stcentury,thetemperaturesensoris文档来自于网络搜索headedinhighprecision,multi-function,bus,standardization,highreliabilityandsafety,developmentof文档来自于网络搜索virtualsensorandnetworksensor,researchmonolithictemperaturemeasuringsystemandotherhigh-tech文档来自于网络搜索directiondeveloprapidly.Sensorsintheapplicationtemperaturecontrollingsystem.Currentmarketexists文档来自于网络搜索mainlysinglepointandmoretwotemperaturemeasurement.Forsinglepointtemperaturefoundment文档来自于网络搜索instrument,mainlyadoptsthetraditionalanalogintegratedtemperaturesensor,whichheatresistance,文档来自于网络搜索thermocouplesensorsmeasuringaccuracy,highmeasurementrange,andgotthegeneralapplication.This文档来自于网络搜索productistemperaturemeasuringrange℃~200mostlybetween800℃,resolution12th,andleast文档来自于网络搜索distinguishabletemperaturein0.001~0.01between.CabinLEDdisplaymodule,showsrangingfrom4to文档来自于网络搜索16.Someinstrumentsalsohasmemoryfunction,canstoreseveralhundredtoafewthousandsetsofdata.文档来自于网络搜索Thisinstrumentcanbeverygoodmeetasingleusersingle-pointmeasurementneeds.Moretemperature文档来自于网络搜索measurement,relativeandsinglepointmeasurementprecisionhascertaingap,althoughrealizedthe文档来自于网络搜索multi-channeltemperaturemeasurementandcontrol,butthepriceisexpensive.Inviewofthepresent文档来自于网络搜索marketsituation,proposedthistopiccansatisfyrequirements,scalableandcost-effectivesingle-chip文档来自于网络搜索multi-channeltemperaturemeasuringsystem.ThroughthefirsttemperaturesensorDS18B20acquisition,文档来自于网络搜索andthenthroughtheC51SCMprocessinganddisplayedonthedigitaltube,canbecollectedindoorora文档来自于网络搜索greenhousearoundindifferentlocationsofthetemperature,withfourdigitaltubetodisplay.Thefirst文档来自于网络搜索digitalpipedisplayacquisitioniswhichway,whichchannel.Threedigitalpipedisplayaftertheacquisition文档来自于网络搜索channelbytemperature,accurateto0.1degrees.2.Thesystemrealizedandrelatedtechnologies2.1.ThesystemisrealizedBythewholecontrolsystemforcoreAT89C51,usingfourwaysoftemperaturesensorDS18B20in文档来自于网络搜索productionsitefordistributionareaoffourdifferenttemperaturemeasurementresultwiththechip文档来自于网络搜索checking,collationstoreanddisplay,andthroughthebuttoncontrol,temperaturewillprocessafterthe第3页LEDdigitaldisplaytocomeout,andthesoftwareassurancesystemanti-interferencecapacity。fourDS1820文档来自于网络搜索connectedtoMCUrespectively,thisschemefourIOmouthoccupyMCUfourIOthough,butthe文档来自于网络搜索microcontrollerIOmouthundertheconditionofmouthnotshortagebythisschemegreatlysimplify文档来自于网络搜索programmingdifficulty,shortenthedesigncycle,alsocanguaranteethestabilityofthesystem.A文档来自于网络搜索multipointconnectionasshown“1-1”1-1multipointconnection2.2.AT89C51ChipintroductionAT89C51isa4KbytesFLASHMemory(ErasableProgrammableandFPEROM-FLASHforthecampaigns文档来自于网络搜索with)lowvoltage,high-performanceCMOSeightmicroprocessors,commonlyknownasthemicrocontroller.文档来自于网络搜索AT89C2051isa2Kbyteswithflashmemorycanbeerasedprogrammableread-onlymemory,SCMcan文档来自于网络搜索eraseread-onlymemorycanberepeatederased1000times.ThisdeviceadoptsATMELhigh-density文档来自于网络搜索non-volatilememorymanufacturingtechnologymanufacturing,andindustrialstandardMCS-51文档来自于网络搜索instructionsetandoutputtubecompatible.Duetothemultifunctional8bitsCPUandwillbeflashingon文档来自于网络搜索singlechipcombinationofmemory,ATMELAT89C51isakindofhighefficientmicrocontroller,AT89C2051文档来自于网络搜索isastreamlinedversion.AT89C51microcontrollerasmanyembeddedcontrolsystem.Arrangeappearance文档来自于网络搜索andpinasshowninfigure"1-2"shownDS1820DS1820DS1820DS1820AT89C51MCUP1.0P1.1P1.2P1.3P3.4DisplayelementButtoncontrolunit第4页1-2AT89C51pinsfigureMajorfeatures:文档来自于网络搜索·andMCS-51compatible·4KbytesprogrammableFLASHmemory·life:1000write/wipecycle·dataretentiontime:10years·thestaticjob:0Hz-24MHz·level3programmemorylock·128x8bitsinternalRAM·32programmableI/Olines·two16timer·5interruptsource·programmableserialchannels·lowpowerconsumptionofidleandpowerlostmode文档来自于网络搜索·pieceinsideoscillatorandclockcircuitTubefeetexplains:VCC:powersupplyvoltage.GND:grounded.P0Mouth:P0mouthaeightleakleveltwo-wayI/Omouthopen,everyfootcanabsorb8TTLgate文档来自于网络搜索current.WhenthepipemouthP0feetfirstwrite1,definedashighresistanceinput.P0canbeusedfor第5页externalprogramdatastorage,itcanbedefinedastheeighthdata/address.InFIASHprogramming,P0文档来自于网络搜索mouthasthesource-codeinputport,whenFIASHcheck,thesource-codeP0output,whenP0external文档来自于网络搜索mustbepulled.P1mouth:mouthisaninternalP1providepull-upresistors8-bittwo-wayI/Omouth,P1mouthbuffer文档来自于网络搜索canreceive4TTLgatecurrentoutput.P1mouthtubefeet,wasthenwrite1forhigh,pullupinsidecanbe文档来自于网络搜索usedasinput,P1mouthbeexternalpulldownforlowelectricityatordinarytimes,willoutputcurrent,this文档来自于网络搜索isduetointernalpullupsake.InFLASHprogrammingandcalibration,P1mouthaseighthaddressto文档来自于网络搜索receive.P2mouth:foraninternalP2mouthonthe8-bitpull-upresistorstwo-wayI/Oport,P2mouthtoreceive,文档来自于网络搜索theoutputbuffer4TTLgatecurrent,whenP2mouthiswritten"1",itstubefeetareinternalpull-up文档来自于网络搜索resistors,andpushasinput.Andsoastheinput,P2mouthfeetareexternaldowntube,willoutputcurrent.文档来自于网络搜索Thisisduetointernalpullupsake.P2mouthwhenusedexternalprogrammemoryor16addressexternal文档来自于网络搜索datamemoryaccess,P2mouthhighoutputaddresseight.Inagivenaddress"1",itusinginternaland文档来自于网络搜索external8addressadvantage,whenforreadingandwritingdatamemory,P2whenthespecialfunction文档来自于网络搜索registersmouthoutputofcontent.P2mouthinFLASHprogrammingandthecalibrationeightaddress文档来自于网络搜索whenreceivinghighsignalandcontrolsignals.P3mouth:P3mouthpipeis8feetwithinternalpull-upresistorstwo-wayI/Oport,mayreceivefourTTL文档来自于网络搜索gatecurrentoutput.WhenP3mouthwriting"1",theyareinternalandhighlevel,andusedasinput.As文档来自于网络搜索input,duetoexternaldrop-downforlowlevel,P3mouthwilloutputcurrent(ILL)thisisduetopullup's文档来自于网络搜索sake.RST:resetinput.WhenoscillatorresetdevicetokeepRSTfeethighleveltwomachinecycletime.文档来自于网络搜索ALE/PROG:whenaccessexternalstorage,addresslatchallowstheoutputlevelofthepositionforlatch文档来自于网络搜索addressbyte.DuringtheFLASHprogramming,thispinforinputprogrammingpulse.Inpeacetime,theALE文档来自于网络搜索withaconstantfrequencycycleoutputisthepulsesignal,thefrequenciesofthe1/6oscillatorfrequency.文档来自于网络搜索Soitcanbeusedagainstexternaloutputpulseorusedfortimingpurpose.Howeveritis:wheneverused文档来自于网络搜索forexternaldatastorage,willskipaALEpulse.IfyouwanttobantheALEoutputcanbeinSFR8EHaddress文档来自于网络搜索for0.Atthistime,onlybyperformingtheALEMOVX,MOVCinstructionisALEtotakeeffect.Inaddition,文档来自于网络搜索thepinswereslightlyup.IfmicroprocessorinexternalexecutionALE,buyabanisinvalid.文档来自于网络搜索/PSEN:externalprogrammemorychoiceofcommunicationnumber.Byexternalprogrammemoryin文档来自于网络搜索duringtheinstructionfetch,eachmachinecycletwice/PSENeffective.Butonavisittoexternaldata文档来自于网络搜索storage,thetwoeffective/PSENsignalswillnotappear.文档来自于网络搜索/EA/VPP:when/EAkeeplowlevelsinthisperiod,theexternalprogrammemory(0000H-FFFFH),文档来自于网络搜索whetherhaveinternalprogrammemory.Noteencryptionmethod1,/EAwillRESETforinternalfocus;第6页When/EAendkeephighelectricityatordinarytimes,internalprogrammemoryhere.DuringtheFLASH文档来自于网络搜索programming,thispinisalsousedVPP12Vprogrammingpower(on).文档来自于网络搜索XTAL1:theinvertingoscillatoramplifierinputandinputtotheinternalclockoperatingcircuit.文档来自于网络搜索XTAL2:fromreverseoscillatoroutput.2.3.DS18B20ChipintroductionDALLASlatestdigitaltemperaturesensorDS18B20profilenew"1-wiredevices"smaller,widerand文档来自于网络搜索voltageappliedtotheDALLASsemiconductorcompanymoreeconomicDS1820digitaltemperaturesensor文档来自于网络搜索istheworldthefirstpieceofsupport"1-wirebus"interfacetemperaturesensor.1-wirebusuniqueand文档来自于网络搜索economiccharacteristics,theusercaneasilyformsensornetworkformeasuringsystem,theconstruction文档来自于网络搜索ofanewconceptintroduction.DS18B20"1-wirebus"withDS1820digitaltemperaturesensorDS18B20文档来自于网络搜索alsosupport"as1-wirebus"interface,measuringtemperaturerangefor-55°C~+125°C,in-10~文档来自于网络搜索+85°Crange,precision°Cfor+0.5.Scenein"1-wirebustemperaturedirectlythedigitalmode,"文档来自于网络搜索cangreatlyimprovethesystemofanti-jamming.Suitableforthesceneinthebadenvironmenttemperaturemeasurement,suchas:environmentcontrol,文档来自于网络搜索equipmentorprocesscontrol,temperaturemeasurementofconsumerelectronics,etc.Andtheprevious文档来自于网络搜索generationproductisdifferent,thenewproductsupport3V~5.5Vvoltagerange,makethesystemdesign文档来自于网络搜索moreflexiblyandconveniently.Butanewgenerationofproductscheaper,smaller.DS18B20canprogram文档来自于网络搜索sets9~12resolution,precision°Cfor+0.5.Optionalsmallerencapsulationway,morewidevoltage文档来自于网络搜索range.Resolutionsetting,anduserssetalarmtemperatureEEPROM,storedinpowerlostandstillsave.文档来自于网络搜索DS18B20performanceisthebestproductofnewgeneration!Performancetopricealsoisverygood!文档来自于网络搜索DS18B20Newperformance:(1)dataavailablesupply,voltagerange:3.0~5.5V;文档来自于网络搜索(2)temperaturemeasuringrange:-55℃~+125in-10~+85℃to+0.5℃whenprecision;文档来自于网络搜索(3)programmableresolutionforthe9~12,thecorrespondingcandistinguishrespectively℃,the文档来自于网络搜索temperatureof0.5℃and0.125℃,by0.250.0625℃;文档来自于网络搜索(4)12resolutioninmost750mstemperatureintodigitalwithin;文档来自于网络搜索(5)negativepressurecharacteristics:poweratthepolarity,thermometerswon'tbecausewhenheating文档来自于网络搜索andburned,butcan'tworknormally.DS18B20Appearanceandinternalstructure:DS18B20internalstructureconsistsmainlyoffourparts:64-bitphotolithographyROM,temperature文档来自于网络搜索sensors,nonvolatiletemperaturealarmtriggersTHTL,configurationandregisters.DS18B20tubefeet第7页arrangementis“1-3”internalstructureis“1-4”文档来自于网络搜索1-3DS18B20tubefeetarrangement(1)DQfordigitalsignalinput/outputterminal;文档来自于网络搜索(2)GNDforpower;(3)VDDforexternalpowersuppliesinput(inparasiticpowerconnectionmodegrounding).文档来自于网络搜索1-4internalstructure3.Debugsimulation3.1.ProtuesProteusisLabeenterelectronicscompanyresearchUKEDAsoftware.Proteusisnotonlytheanalogand文档来自于网络搜索digitalcircuit,d/ahybridcircuitdesignandsimulationplatform,butalsoiscurrentlytheworld'smost文档来自于网络搜索advanced,themostcompletevarioustypesofmicrocontrollersystemdesignandsimulationplatform.It第8页reallyrealizedcompleteoncomputerschematicdesign,fromcircuitanalysisandsimulationandsingle-chip文档来自于网络搜索microcomputerandgradedebuggingandsimulation,codesystemtestandfunctionalverificationofthe文档来自于网络搜索PCBformationtocompletethedesignanddevelopmentprocessofelectronic.Proteusproductseriesalso文档来自于网络搜索containsarevolutionaryVSMtechnologybasedonmicrocontrol,canthedesignwithallperipheral文档来自于网络搜索electronicdevicesimulationtogether.FirststartProteusandProteuscomponentsfromthelibraryselection文档来自于网络搜索needdrawingdiagramandsetcomponent,thecorrespondingelementparametervalues3.2.KeilcKeilVision2isaboutthe8051seriesMCUKeilcompanyofdevelopmenttoolscanbeusedtocompileC文档来自于网络搜索sourcecode,assemblerssourceprogram,connectionandrelocationtargetfilesandlibraries,genbuilt:文档来自于网络搜索documents,debuggingpurposesprocedure,etc,itisakindofintegrationofdocumentmanagement文档来自于网络搜索compileenvironment.Itintegratesdocumenteditingprocessing,compileconnection,projectmanagement,文档来自于网络搜索window,toolscitedandsoftwarecopytruedebuggingandotherfunctions,isprettypowerfuldevelopment文档来自于网络搜索tool.Inkeilinsidecompile,theproceduresrequiredcommissioning3.3.alignment(1)detectionTCP/IP.文档来自于网络搜索(2)duplicatetheProteusinstallationdirectoryvdm51.Whofolderkeilc/C51/DLLtobindirectory.文档来自于网络搜索(3)modifytheinstallationdirectoryKeiltools.TDRV4=BIN,addtheDLL.VDM51.\文档来自于网络搜索(4)intheschematicdrawingProteus,in"Debugmenu,select"UseRemoteDebughand".文档来自于网络搜索(5)inopeninaprojectKeil,right-clickTarget1,choosefor-Target'Target1'.Intheopendialogbox文档来自于网络搜索select"De-bugTAB,selectanduseVSMProteusEmulatorsimulation(figure6shows),click"Ok文档来自于网络搜索"completeDebugSettings.6graph6suchKeilProteusandisconnected,thesimulationresultscanbe文档来自于网络搜索inProteusorKeil.ThiscircuitsystemUSES"1-wirebus"digitalsensorDS18B20torealizethe文档来自于网络搜索collectionoftemperature,usingsevensegmentdigitaltubedatashows.Willprogramandsimulation文档来自于网络搜索diagramrealizationcircuitconnected,simulation第9页中文翻译稿翻译苏州大学应用技术学院07电子学号朱琳分布式温度传感器文档来自于网络搜索1传感器简介1.1温度传感器的背景在人类生活环境中温度扮演着一个极其重要的角色。无论你住在哪里从事什么工作都会与温度打交文档来自于网络搜索道。自18世纪工业时代以来工业革命对能否控制发送显示温度有着绝对的联系。在冶金、锻钢、石化、水泥、医学等产业中可以这样说几乎80%的工业部门不得不考虑温度的因素。温度对工业来说如此重要因此也推动了温度传感器的发展。1.2温度传感器的发展传感器主要大体经过了三个发展阶段模拟集成温度传感器。该传感器是采用硅半导体集成工艺制成因文档来自于网络搜索此亦称硅传感器或单片集成温度传感器。此种传感器具有功能单一(仅测量温度)、测温误差小、价格低、响应速度快、传输距离远、体积小、功耗低适合远距离测温、控温不需要进行非线性校准外围电路简单。它是目前在国内外应用最为普遍的一种集成传感器典型产品有AD590、AD592、TMP17、LM135等文档来自于网络搜索模拟集成温度控制器。模拟集成温度控制器主要包括温度控制开关、可编程温度控制器典型产品有LM56、AD22105和MAX6509。某些增强型集成温度控制器(例如TC652/653)中还包含了A/D转换器以及固化好文档来自于网络搜索的程序这些工艺与智能温度传感器有某些相似之处。但它自成系统工作时并不受微处理器的控制这是智能温度传感器和非智能之间的主要区别智能温度传感器(亦称数字温度传感器)是20世纪90年代中期问世的。它是微电子技术、计算机技术和自动测试技术(ATE)的结晶。智能温度传感器内部都包含温度传感器、A/D转换器、信号处理器、存储器(或寄存器)和接口电路。有的产品还带多路选择器、中央控制器(CPU)、文档来自于网络搜索随机存取存储器(RAM)和只读存储器(ROM)。智能温度传感器的特点是能输出温度数据及相关的温度控制文档来自于网络搜索量适配各种微控制器(MCU)。1.3单点与多点温度传感器温度传感器的发展趋势进21世纪后温度传感器正朝着高精度、多功能、总线标准化、高可靠性及安文档来自于网络搜索全性、开发虚拟传感器和网络传感器、研制单片测温系统等高科技的方向迅速发展。传感器在温度测控系统中的应用目前市场主要存在单点和多点两种温度测量仪表。对于单点温测仪表主要采用传统的模拟集成第10页温度传感器其中又以热电阻、热电偶等传感器的测量精度高测量范围大而得到了普遍的应用。此种文档来自于网络搜索产品测温范围大都在-200℃~800℃之间分辨率12位最小分辨温度在0.001~0.01之间。自带LED文档来自于网络搜索液晶显示模块显示4位到16位不等。有的仪表还具有存储功能可存储几百到几千组数据。该类仪表可很好的满足单个用户单点测量的需要。多点温度测量仪表相对与单点的测量精度有一定的差距虽然实现了多路温度的测控但价格昂贵。针对目前市场的现状本课题提出了一种可满足要求、可扩展的并且性价比高的单片机多路测温系统。通过温度传感器DS18B20采集然后通过C51单片机处理并在数码管文档来自于网络搜索上显示可以采集室内或温室中四处不同位置的温度用四个数码管来显示。第一个数码管显示所采集的是哪一路哪个通道。后三个数码管显示所采集通道的温度值精确到0.1度。2系统的实现及相关技术2.1系统的实现整个控制系统采用AT89C51芯片采用多线连接就是四个DS1820分别连接到单片机的四个IO口文档来自于网络搜索采集到的温度结果通过串口通信然后芯片将采集到的数据处理在外部显示器显示出来并且能够实现外部键盘的控制。温度在LED液晶显示屏显示出来后通过软件编程确保系统有一定的抗干扰能力。这种方案虽然占用单片机的四个IO口但在单片机IO口不紧缺的情况下采用这种方案大大的简化了编程难度缩短了设计周期同时也能保证系统的稳定。多线连接方案的框图如“图1-1”所示图1-1DS1820多线连接方案2.2.AT89C51单片机简介AT89C51是一种带4K字节FLASH存储器FPEROM—FlashProgrammableandErasableReadOnly文档来自于网络搜索Memory的低电压、高性能CMOS8位微处理器俗称单片机。AT89C2051是一种带2K字节闪存可编程文档来自于网络搜索可擦除只读存储器的单片机。单片机的可擦除只读存储器可以反复擦除1000次。该器件采用ATMEL高密度非易失存储器制造技术制造与工业标准的MCS-51指令集和输出管脚相兼容。由于将多功能8位CPU和闪存存储器组合在单个芯片中ATMEL的AT89C51是一种高效微控制器AT89C2051是它的一种精简版本。DS1820文档来自于网络搜索DS1820DS1820DS1820AT89C51单片机P1.0P1.1P1.2P1.3P3.4显示单元按键控制单元第11页AT89C51单片机为很多嵌入式控制系统提供了一种灵活性高且价廉的方案。外形及引脚排列如图“图1-2”文档来自于网络搜索所示图1-2AT89C51引脚图主要特性·与MCS-51兼容·4K字节可编程FLASH存储器·寿命1000写/擦循环·数据保留时间10年·全静态工作0Hz-24MHz·三级程序存储器锁定·128×8位内部RAM·32可编程I/O线·两个16位定时器/计数器·5个中断源·可编程串行通道·低功耗的闲置和掉电模式·片内振荡器和时钟电路管脚说明VCC供电电压。第12页GND接地。P0口P0口为一个8位漏极开路双向I/O口每脚可吸收8TTL门电流。当P0口的管脚先要写入高电平被定义为高阻输入。P0能够用于外部程序数据存储器它可以被定义为低八位数据或地址总线。在FIASH文档来自于网络搜索编程时P0口作为原码输入口当FIASH进行校验时P0输出原码此时P0外部必须被拉高。P1口P1口是一个内部提供上拉电阻的8位双向I/O口P1口缓冲器能接收输出4TTL门电流。P1口管脚写入高电平后被内部上拉为高可用作输入P1口被外部下拉为低电平时将输出电流这是由于内部上拉的缘故。在FLASH编程和校验时P1口作为高八位地址接收。P2口P2口为一个内部上拉电阻的8位双向I/O口P2口缓冲器可接收输出4个TTL门电流当P2口被写入高电平时其管脚被内部上拉电阻拉高且作为输入。并因此作为输入时P2口的管脚被外部拉低将输出电流。这是由于内部上拉的缘故。P2口当用于外部程序存储器或16位地址外部数据存储器进行存取时P2口输出地址的高八位。在给出地址“1”时它利用内部上拉优势当对外部八位地址数据存储器进行读写时P2口输出其特殊功能寄存器的内容。P2口在FLASH编程和校验时接收高八位地址信号和控制信号。P3口P3口管脚是8个带内部上拉电阻的双向I/O口可接收输出4个TTL门电流。当P3口写入高电平后它们被内部上拉为高电平并用作输入。作为输入由于外部下拉为低电平P3口将输出电流ILL这是由于上拉的缘故。RST复位输入。当振荡器复位器件时要保持RST脚两个机器周期的高电平时间。ALE/PROG当访问外部存储器时地址锁存允许的输出电平用于锁存地址的地位字节。在FLASH编程期间此引脚用于输入编程脉冲。在平时ALE端以不变的频率周期输出正脉冲信号此频率为振荡器频率的1/6。因此它可用作对外部输出的脉冲或用于定时目的。然而要注意的是每当用作外部数据存储器时将跳过一个ALE脉冲。如想禁止ALE的输出可在SFR8EH地址上置0。此时ALE只有在执行MOVXMOVC文档来自于网络搜索指令是ALE才起作用。另外该引脚被略微拉高。如果微处理器在外部执行状态ALE禁止置位无效。/PSEN外部程序存储器的选通信号。在由外部程序存储器取指期间每个机器周期两次/PSEN有效。但在访问外部数据存储器时这两次有效的/PSEN信号将不出现。/EA/VPP当/EA保持低电平时则在此期间外部程序存储器0000H-FFFFH不管是否有内部程序存文档来自于网络搜索储器。注意加密方式1时/EA将内部锁定为RESET当/EA端保持