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第1页外文文献资料ThedevelopmentandapplicationofsinglechipmicrocomputertechnologyThemonolithicintegratedcircuitsaidthatthemonolithicmicrocontroller,itisnotcompletessomelogicalfunctionthechip,butintegratesacomputersystemtoachipon.Summaryspeaking:Achiphasbecomeacomputer.Itsvolumeissmall,thequalityislight,andthepricecheap,forthestudy,theapplicationandthedevelopmenthasprovidedtheconvenientcondition.Atthesametime,thestudyusemonolithicintegratedcircuitisunderstandsthecomputerprincipleandthestructurebestchoice.Themonolithicintegratedcircuitinterioralsouseswiththecomputerfunctionsimilarmodule,forinstanceCPU,memory,parallelmainline,butalsohaswiththeharddiskbehaveidenticallythememorycomponent7whatisdifferentisitsthesepartperformanceisoppositeourhome-usecomputerweakmany,butthepriceisalsolow,generallydoesnotsurpass10YuanthenMadesomecontrolelectricapplianceonekindwithitisnottheverycomplexworkfoot,Weusenowthecompletelyautomaticdrumwasher,theplatoonpetti-coatpipe:VCDandsoonInsidetheelectricalappliancesmayseeitsform!Itismainlytakesthecontrolsectionthecorepart.Itisonekindofonline-likereal-timecontrolcomputer,online-likeisthescenecontrol,needstohavethestrongantijammingability,thelowcost,thisisalsoandtheoff-linetypecomputer(forinstancehomeusePC,)maindifferenceThemonolithicintegratedcircuitisdependingontheprocedure,andmayrevise.Realizesthedifferentfunctionthroughthedifferentprocedure,particularlyspecialuniquesomefunctions,thisisothercomponentneedstotaketheverybigefforttobeabletoachieve,somearethefloweredbigstrengthisalsoverydifficulttoachieve.Oneisnottheverycomplexfunction,ifdevelopsinthe50swiththeUS74series,orthe60ssCD4000第2页seriesthesepurehardwaredodecides,theelectriccircuitcertainlyarcabigPCBboard!Butif,ifsucceededinthe70swiththeUSputsinthemarkettheseriesmonolithicintegratedcircuit,theresultwillhavethehugedifference.Becauseonlythemonolithicintegratedcircuitcompilesthroughyoutheproceduremayrealizethehighintelligence,highefficiency,aswellasredundantreliabilityTheCPUisthekeycomponentofadigitalcomputer.Itspurposeistodecodeinstructionreceivedfrommemoryandperformtransfers,arithmetic,logic,andcontroloperationswithdatastoredininternalregisters,memory,orI/Ointerfaceunits.Externally,theCPUprovidesoneormorebusesfortransferringinstructions,data,andcontrolinformationtoandfromcomponentsconnectedtoit.Amicrocontrollerispresentinthekeyboardandinthemonitorinthegenericcomputer;thusthesecomponentsarealsoshaded.Insuchmicrocontrollers,theCPUmaybequitedifferentfromthosediscussedinthischapter.Thewordlengthsmaybeshort,thenumberofregisterssmall,andtheinstructionsetslimited.Performance,relativelyspeaking,ispoor,butadequateforthetask.Mostimportant,thecostofthesemicrocontrollersisverylow,makingtheirusecosteffective.Becausethemonolithicintegratedcircuittothecostissensitive,thereforepresentoccupiesthedominantstatusthesoftwareisthemostpreliminaryassemblylanguage7itwasexceptthebinarymachinecodeabovethemostpreliminarylanguage,sincewhyweresuchpreliminarymustuse?Whyhigh-leveldidthelanguagealreadyachievethevisualizationprogramminglevelnottouse?Thereasonisverysimple,isthemonolithicintegratedcircuitdocsnothavehomecomputersuchCPU,andalsohasnotlookedliketheharddisksuchmassmemoryequipment.Insideevenifavisualizationhigherorderlanguagecompilationscriptonlythenabutton,alsowillachieveseveraldozensKthesizes!DoesnotspeakanythingregardingthehomeusePCharddisk,butsaysregardingthemonolithicintegratedcircuitcannotaccept.ThemonolithicintegratedcircuitinthehardwaresourceaspectsusefactormustveryGaoCaixing,thereforeassembly,althoughprimitiveactuallymassivelyisusing,Sametruth,ifattainssupercomputersonoperatingsystemandtheapplicationsoftwarehomeusePC第3页tocomeupthemovement,homeusePCcouldalsonotwithstand.Itcanbesaidthatthe20thcenturysurmountedthreetheelectricitythetime,namelytheelectricaltime,theElectronicAgeandalreadyenteredcomputertime.However,thiskindofcomputer,usuallyreferstothepersonalcomputer,iscalledPCmachine.Itbythemainengine,thekeyboard,themonitorandsooniscomposed.Alsohasakindofcomputer,mostpeopleactuallynothowfamiliar.Thiskindofcomputerisentrustswiththeintelligenceeachkindofmechanicalmonolithicintegratedcircuit(alsotocallmicrocontroller).,Thiskindofcomputerssmallestsystemonlyhasusedasthenamesuggestsapieceofintegratedcircuit,thencarriesonthesimpleoperationandthecontrol.Becauseitsvolumeissmall,usuallyhidesinisaccusedthemachinerythebelly.Itintheentireinstallment,playsishavinglikethehumanbrainsrole,itwentwrong,theentireinstallmentparalyzed.Now,thiskindofmonolithicintegratedcircuitsusedomainalreadyverywidespread,liketheintelligentmeasuringappliance,thesolidworkpaidbytimecontrol,thecommunicationequipment,theguidancesystem,thedomesticelectricappliancesandsoon,Onceeachproductusedthemonolithicintegratedcircuit,couldgetupcausestheeffectwhichtheproductturnedtoanewgeneration,oftenbeforeproductrangecrownbyadjective-intelligence,likeintelligencewasherandsoon.Nowsomefactorystechnicalpersonnelorotherextra-curricularelectronicexploiterdocertainproducts,arenottheelectriccircuitaretoocomplex,isthefunctionistoosimple,andisimitatedextremelyeasily.Investigatesitsreason,possiblyoncard,intheproducthasnotusedonthemonolithicintegratedcircuitorotherprogrammablelogicalcomponent.StructureandfunctionoftheMCS-51seriesone-chipcomputerMCS-51isanameofapieceofone-chipcomputerserieswhichIntelCompanyproduces.Thiscompanyintroduced8top-gradeone-chipcomputersofMCS-51seriesin1980afterintroducing8one-chipcomputersofMCS-48seriesin1976.Itbelongtoalotofkindsthislineofone-chipcomputerthechipshave,suchas8051,8031,8751,80C51BH,80C31BH,etc.,theirbasiccomposition,basicperformanceandinstructionsystemareallthesame.8051dailyrepresentatives-51serialone-chipcomputers.第4页Anone-chipcomputersystemismadeupofseveralfollowingparts:(1)Onemicroprocessorof8(CPU).(2)AtslicedatamemoryRAM(128B/256B),itusenotdeposittingnotcanreading/datathatwrite,suchasresultnotmiddleofoperation,finalresultanddatawantedtoshow,etc.(3)ProcedurememoryROM/EPROM(4KB/8KB),isusedtopreservetheprocedure,someinitialdataandforminslice.ButdoesnottakeROM/EPROMwithinsomeone-chipcomputers,suchas8031,8032,80C,etc.(4)Four8runsidebysideI/OinterfaceP0fourP3,eachmouthcanuseasintroduction,mayuseasexportingtoo.(5)Twotimer/counter,eachtimer/countermaysetupandcountintheway,usedtocounttotheexternalincident,cansetupintoatimingwaytoo,andcanaccordingtocountorresultoftimingrealizethecontrolofthecomputer.(6)Fivecutoffcuttingoffthecontrolsystemofthesource.(7)OneallduplexingserialI/OmouthofUART(universalasynchronousreceiver/transmitter(UART),isitrealizeone-chipcomputerorone-chipcomputerandserialcommunicationofcomputertousefor.(8)Stretchoscillatorandclockproducecircuit,quartzcrystalfinelytuneelectriccapacityneedouter.Allowoscillationfrequencyas12megahertasnowatmost.Everytheabove-mentionedpartwasjoinedthroughtheinsidedatabus.Amongthem,CPUisacoreoftheone-chipcomputer,itisthecontrolofthecomputerandcommandcentre,madeupofsuchpartsasarithmeticunitandcontroller,etc.Thearithmeticunitcancarryon8personsofarithmeticoperationandunitALUoflogicoperationwhileincludingone,the1storingdevicetemporariliesof8,storingdevice2temporarily,8saccumulationdeviceACC,registerBandprocedurestateregisterPSW,etc.PersonwhoaccumulateACCcountby2inputendsenteredofcheckingetc.temporarilyasoneoperationoften,comefrompersonwhostore1operationisitisitmakeoperationtogoontocounttemporarily,operationresultandloopbackACCwithanotherone.Inaddition,ACCisoftenregardedasthetransferstationofdatatransmissionon8051inside.Thesameasgeneralmicroprocessor,itisthebusiestregister.HelprememberingthatagreeingwithAexpressesintheorder.Thecontrollerincludestheprocedurecounter,theorderisdepositted,theorderdecipher,theoscillatorandtimingcircuit,etc.Theprocedurecounterismadeupof第5页counterof8fortwo,amountsto16.Itisabyteaddresscounteroftheprocedureinfact,thecontentisthenextIAthatwillcarriedoutinPC.Thecontentwhichchangesitcanchangethedirectionthattheprocedurecarriesout.Shakethecircuitin8051one-chipcomputers,onlyneedouterquartzcrystalandfrequencytofinelytunetheelectriccapacity,itsfrequencyrangeisits12MHZof1.2MHZ.Thispulsesignal,as8051basicbeatsofworking,namelytheminimumunitoftime.8051isthesameasothercomputers,theworkinharmonyunderthecontrolofthebasicbeat,justlikeanorchestraaccordingtothebeatplaythatiscommanded.ThereareROM(procedurememory,canonlyread)andRAMin8051slices(datamemory,canisitcanwrite)twotoread,theyhaveeachindependentmemoryaddressspace,disposewaytobethesamewithgeneralmemoryofcomputer.Procedure8051memoryand8751sliceprocedurememorycapacity4KB,addressbeginfrom0000H,usedforpreservingtheprocedureandformconstant.Data8051-87518031ofmemorydatamemory128B,addressfalse00FH,useformiddleresulttodepositoperation,thedataarestoredtemporarilyandthedataarebufferedetc.InRAMofthis128B,thereisunitof32bytesesthatcanbeappointedasthejobregister,thisandgeneralmicroprocessorisdifferent,8051sliceRAMandjobregisterrankoneformationthesametoarrangethelocation.ItisnotverythesamethatthememoryofMCS-51seriesone-chipcomputerandgeneralcomputerdisposesthewayinaddition.Generalcomputerforfirstaddressspace,ROMandRAMcanarrangeindifferentspacewithintherangeofthisaddressatwill,namelytheaddressesofROMandRAM,withdistributingdifferentaddressspaceinaformation.Whilevisitingthememory,correspondingandonlyanaddressMemoryunit,canROM,itcanbeRAMtoo,andbyvisitingtheordersimilarly.ThiskindofmemorystructureiscalledthestructureofPrinceton.8051memoriesaredividedintoprocedurememoryspaceanddatamemoryspaceonthephysicsstructure,therearefourmemoryspacesinall:Theprocedurestoresinoneanddatamemoryspaceoutsidedatamemoryandoneinprocedurememoryspaceandoneoutsideone,thestructureformsofthiskindofproceduredeviceanddatamemoryseparatedformdatamemory,calledHarvardstructure.Butusetheanglefromusers,8051memoryaddressspaceisdividedintothree第6页kinds:(1)Intheslice,arrangeblocksofFFFFH,0000Hoflocation,inunisonoutsidetheslice(use16addresses).(2)Thedatamemoryaddressspaceoutsideoneof64KB,theaddressisarrangedfrom0000H64KBFFFFH(with16addresses)tootothelocation.(3)Datamemoryaddressspaceof256B(use8addresses).Threeabove-mentionedmemoryspaceaddressesoverlap,fordistinguishinganddesigningtheordersymbolofdifferentdatatransmissionintheinstructionsystemof8051:CPUvisitslice,ROMorderspendMOVC,visitblockRAMorderusesMOVXoutsidetheslice,RAMorderusesMOVtovisitinslice.8051one-chipcomputerhavefour8walkabreastI/Oport,callP0,P1,P2andP3.Eachportis8accuratetwo-waymouths,accountsfor32pinsaltogether.EveryoneI/Olinecanbeusedasintroductionandexportedindependently.Eachportincludesalatch(namelyspecialfunctionregister),oneexportsthedriverandaintroductionbuffer.Makedatacanlatchwhenoutputting,datacanbufferwhenmakingintroduction,butfourfunctionofpasswaytheseself-same.Expandamongthesystemofmemoryoutsidehavingslice,fourportthesemayserveasaccuratetwo-waymouthofI/Oincommonuse.Expandamongthesystemofmemoryoutsidehavingslice,P2mouthseehigh8addressoff;P0mouthisatwo-waybus,sendtheintroductionof8lowaddressesanddata/exportintimesharingOutputgrade,P3ofmouth,P1ofP1,connectwithinsidehaveloadresistanceofdrawing,everyoneoftheycandrive4ModelLSTTLloadtooutput.Aswhileinputtingthemouth,anyTTLorNMOScircuitcandriveP1of8051one-chipcomputersasP3mouthinanormalway.Becausedrawresistanceonoutputgradeofthemhave,canopenawaycollectortooordrain-sourceresistanceisiturgetoopenaway,donotneedtohavetheresistanceofdrawingouterly.Mouthsareallaccuratetwo-waymouthstoo.Whentheconductisinput,mustwritethecorrespondingportlatchwith1first.Asto80C51one-chipcomputer,portcanonlyoffermilliampereofoutputelectriccurrents,isitoutputmouthgowhenurgingoneordinarybasingoftransistortoregardas,shouldcontactaresistanceamongtheportandtransistorbase,inordertotheelectricitywhilerestrainingthehighlevelfromexportingP1P3Beingrestoredtothethroneistheoperationof第7页initializingofanone-chipcomputer.ItsmainfunctionistoturnPCinto0000Hinitially,maketheone-chipcomputerbegintoholdtheconductprocedurefromunit0000H.Exceptthattheonesthatenterthesystemareinitializednormally,asbecauseprocedureoperateitmakemistakesoroperatetherearentmistake,inordertoextricateoneselffromapredicament,needtobepressedandrestoredtothethronethekeyrestartingtoo.Itisaninputendwhichisrestoredtothethronethesignalin8051ChinaRSTpin.Restoretothethronesignalhighleveleffective,shouldsustain24shakecycle(namely2machinecycles)theaboveitseffectivetimes.If6offrequencyofutilizationbrillianttoshake,restoretothethronesignaldurationshouldexceed4delicatetofinishrestoringtothethroneandoperating.Producethelogicpictureofcircuitwhichisrestoredtothethronethesignal:Restoretothethronethecircuitandincludetwopartsoutsideinthechipentirely.Outsidethatcircuitproducetorestoretothethronesignal(RST)handovertoSchmittstrigger,restoretothethronecircuitsampletooutput,SchmittoftriggerconstantlyineachS5P2,machineofcycleinhavingonemore,thenjustgotandrestoredtothethroneandoperatedthenecessarysignalinsidly.Restoretothethroneresistanceofcircuitgenerally,electriccapacityparametersuitablefor6brillianttoshake,canisitrestoretothethronesignalhighleveldurationgreaterthan2machinecyclestoguarantee.Beingrestoredtothethroneinthecircuitissimple,itsfunctionisveryimportant.Piecesofone-chipcomputersystemcouldnormalrunning,shouldfirstcheckitcanrestoretothethronenotsucceeding.Checkingandcanpoponesheadandmonitorthepinwiththeoscillographtentatively,pushandisrestoredtothethronethekey,thewaveformthatobservesandhasenoughrangeisexported(instantaneous),canalsothroughisitrestoretothethronecircuitgroupholdingvaluecarryontheexperimenttochange.Withthecostantgrowingconsumptionoffossilenergy,globalenergycrisisandenvironmentalproblemshavebecomemoreandmoreacute.Amongvariousgreenrenewableenergyresources,solarenergyhasdrawntheattentionfromthescientificcirclesofvariouscountriesduetoitsunique第8页advantagessuchasbountlessstoragecontent,cleanessandsafety,andeasinesstoobtain.Inparticular,theapplicationofsolarphotovoltaictechnologyhasbecomeauniversalfocus.Chinahasrelativelyscarcefossilenergyresourceswhileahugeenergyconsumption.Therefore,theresearchandapplicationofsolarphotovoltaictechnologyhasimportantstrategicmeaningforthefutureeconomicdevelopmentofChina.Abasicsolarphotovoltaicsystemisgenerallycomposedofsolarpanels,storagebatteries,DC(directcurrent)controlsystemandinverters,amongwhich,DCcontrolsystemisthecentralpartofthesolarphotovoltaicsystem.第9页中文翻译稿单片机的发展与应用单片机又称单片微控制器,它不是完成某一个逻辑功能的芯片,而是把一个计算机系统集成到一个芯片上。概括的讲:一块芯片就成了一台计算机。它的体积小、质量轻、价格便宜、为学习、应用和开发提供了便利条件。同时,学习使用单片机是了解计算机原理与结构的最佳选择。单片机内部也用和电脑功能类似的模块,比如CPU,内存,并行总线,还有和硬盘作用相同的存储器件,不同的是它的这些部件性能都相对我们的家用电脑弱很多,不过价钱也是低的,一般不超过10元即可,用它来做一些控制电器一类不是很复杂的工作足矣了。我们现在用的全自动滚筒洗农机、排烟罩、VCD等等的家电里面都可以看到它的身影!它主要是作为控制部分的核心部件。它是一种存线式实时控制计算机,在线式就是现场控制,需要的是有较强的抗干扰能力,较低的成本,这也是和离线式计算机的(比如家用PC)的主要区别。单片机是靠程序的,并且可以修改。通过不同的程序实现不同的功能,尤其是特殊的独特的一些功能,这是别的器件需要费很多人力气才能做到的,有些则是花人力气也很难做到的。一个不是很复杂的功能要是用美同50年代开发的74系列,或者60年代的CD4000系列这些纯硬件来搞定的话,电路一定是一块大PCB板!但是如果要是用美国70年代成功投放市场的系列单片机,结果就会有天壤之别!只因为单片机的通过你编写的程序可以实现高科能,高效率,以及高可靠性!CPU(中央处理单元)是数字计算机的重要组成部分,其目的是对从内存中接收的指令进行译码,同时对存储于内部寄存器、存储器或输入输出接口单元的数据惊醒传输、算术运算、逻辑运算以及控制运算。在外部,CPU位转换指令数据和控制信息提供一个或多个总线并从组件连接到它。一个微控制器出现在普通电脑的键盘和检测器中,但是这些组件也被屏蔽。在这种微控制器中,与我们所讨论的CPU可能不同。字长也许更短,编制数量少,指令集有限。相对而言,性能差,但对完成任务来说足够了。最重要的是它的微控制器的成本很低,符合成本效应。由于单片机对成本是敏感的,所以目前占统治地位的软件还是最低级汇编语言,它是除了二进制机器码以上最低级的语言了,既然这么低级为什么还要用呢?很多高级的语言已经达到了可视化编程的水平为什么不用呢?原因简单,就是单片机没有家用计算第10页机那样的CPU,也没有像硬盘那样的海量存储设备。一个可视化高级语言编写的小程序里面即使只有一个按钮,也会达到几十K的尺寸!对于家用PC的硬盘来讲没什么,可是对于单片机来讲是不能接受的。单片机在硬件资源方面的利用率必须很高才行,所以汇编虽然原始却还是在大量使用。一样的道理,如果把巨型计算机上的操作系统和应用软件拿到家用PC上来运行,家用PC的也是承受不了的。可以说,二十世纪跨越了三个“电”的时代,即电气时代、电子时代和现已进入的电脑时代。不过,这种电脑,通常是指个人计算机,简称PC机。它白主机、键盘、显示器等组成。还有一类计算机,人多数人却不怎么熟悉。这种计算机就是把智能赋予各种机械的单片机(亦称微控制器)。顾名思义,这种计算机的最小系统只用了一片集成电路,即可进行简单运算和控制。因为它体积小,通常都藏在被控机械的“肚子”里。它在整个装置中,起着有如人类头脑的作用,它出了毛病,整个装置就瘫痪了。现在,这种单片机的使用领域已十分广泛,如科能仪表、实时T控、通讯设备、导航系统、家用电器等。各种产品。一旦用上了单片机,就能起到使产品升级换代的功效,常在产品名称前冠以形容词一一“智能型”,如智能型洗衣机等。现在有些工厂的技术人员或其它业余电子开发者搞出来的某些产品,不是电路太复杂,就是功能太简单且极易被仿制。究其原因,可能就卡在产品未使用单片机或其它可编程逻辑器件上。51系列单片机是英特尔公司生产的具有一定结构和功能的单片机产品。这家公司在1976年引入8位MCS-48系列单片机后,于1980年又推出了8位高档的MCS-51系列单片机。它包含很多种这类型的单片机,如8051,8031,8751,80C51BH,80C31BH等,它们的基本组成,基本性能和指令系统都是一样的。一般情况习惯用8051来代表51系列单片机。一个单片机的系统是由以下几部分组成:(1)一个8位CPU微处理器。(2)静态随机存取存储器,能够储存程序运行过程中产生的数据。(3)程序存储器ROM/EPROM中(4KB/8KB),用来保存程序和一些初始数据。但是在一些单片机中不使用ROM/EPROM中,如8031,8032,80c系列等。(4)4个8排的I/O并行接口P0P3,每个口可以用作输入,也可以用作输出。(5)2个定时器/计数器,每个定时器/计数器可设置计数用来计数外部事件,可以设置成常用的定时方式,并可以根据计算或结果控制单片机的运行。(6)五个中断源控制系统。(7)1个双向串行I/O口的UART(通用异步接收器/发送器UART),用于实现单片机的串行通信。(8)振荡器和时钟产生电路,需要外部电源的石英晶体微调电路,允许接在12v的振荡频率上。上述部分通过内部数据总线连接。其中,CPU是单片机的核心,它是单片机的控制和指挥中心,ALU算数逻辑运算单元可进行算术运算和逻辑运算,由1个8暂时存储器,和2个8位的累加器组成。Acc累加器是ALU运算结果的存放单元,一般数据通过它来传送。此外,Acc往往被视为对8051
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