本文由xinyuchenl23贡献wps文档可能在WAP端浏览体验不佳。建议您优先选择TXT，或下载源文件到本机查看。Single-chipisanintegratedonasinglechipacompletecomputersystem.Eventhoughmostofhisfeaturesinasmallchip,butithasaneedtocompletethemajorityofcomputercomponents:CPU,memory,internalandexternalbussystem,mostwillhavetheCore.Atthesametime,suchasintegratedcommunicationinterfaces,timers,real-timeclockandotherperipheralequipment.Andnowthemostpowerfulsingle-chipmicrocomputersystemcanevenvoice,image,networking,inputandoutputcomplexsystemintegrationonasinglechip.Alsoknownassingle-chipMCU(Microcontroller),becauseitwasfirstusedinthefieldofindustrialcontrol.Onlybythesingle-chipCPUchipdevelopedfromthededicatedprocessor.ThedesignconceptisthefirstbyalargenumberofperipheralsandCPUinasinglechip,thecomputersystemsothatsmaller,moreeasilyintegratedintothecomplexanddemandingonthevolumecontroldevices.INTELtheZ80isoneofthefirstdesigninaccordancewiththeideaoftheprocessor,Fromthenon,theMCUandthedevelopmentofadedicatedprocessorpartedways.Earlysingle-chip8-bitorallofthefour.OneofthemostsuccessfulisINTELs8031,becausetheperformanceofasimpleandreliableaccesstoalotofgoodpraise.Sincethenin8031todevelopasingle-chipmicrocomputersystemMCS51series.Basedonsingle-chipmicrocomputersystemofthesystemisstillwidelyuseduntilnow.Asthefieldofindustrialcontrolrequirementsincreaseinthebeginningofa16-bitsingle-chip,butnotidealbecausethepricehasnotbeenverywidelyused.Afterthe90swiththebigconsumerelectronicsproductdevelopment,single-chiptechnologyisahugeimprovement.INTELi960SerieswithsubsequentARMinparticular,abroadrangeofapplications,quicklyreplacedby32-bitsingle-chip16-bitsingle-chiphigh-endstatus,andenterthemainstreammarket.Traditional8-bitsingle-chipperformancehasbeentherapidincreaseinprocessingpowercomparedtothe80storaiseafewhundredtimes.Atpresent,thehigh-end32bitsingle-chipfrequencyover300MHz,theperformanceofthemid-90scloseontheheelsofaspecialprocessor,whiletheordinarypriceofthemodeldroppedtooneU.S.dollars,themosthighendmodels,only10U.S.dollars.Contemporarysingle-chipmicrocomputersystemisnolongeronlythebare-metalenvironmentinthedevelopmentanduseofalargenumberofdedicatedembeddedoperatingsystemiswidelyusedinthefullrangeofsingle-chipmicrocomputer.InPDAsandcellphonesasthecoreprocessingofhigh-endsingle-chiporevenadedicateddirectaccesstoWindowsandLinuxoperatingsystems.Morethanadedicatedsingle-chipprocessorsuitableforembeddedsystems,soitwasuptotheapplication.Infactthenumberofsingle-chipistheworldslargestcomputer.Modernhumanlifeusedinalmosteverypieceofelectronicandmechanicalproductswillhaveasingle-chipintegration.Phone,telephone,calculator,homeappliances,electronictoys,handheldcomputersandcomputeraccessoriessuchasamouseintheDepartmentareequippedwith1-2singlechip.Andpersonalcomputersalsohavealargenumberofsingle-chipmicrocomputerintheworkplace.Vehiclesequippedwithmorethan40Departmentofthegeneralsingle-chip,complexindustrialcontrolsystemsandevensingle-chipmayhavehundredsofworkatthesametime!SCMisnotonlyfarexceedsthenumberofPCandotherintegratedcomputing,evenmorethanthenumberofhumanbeings.HardwaveintroductionThe8051familyofmicrocontrollersisbasedonanarchitecturewhichishighlyoptimizedforembeddedcontrolsystems.ItisusedinawidevarietyofapplicationsfrommilitaryequipmenttoautomobilestothekeyboardonyourPC.SecondonlytotheMotorola68HC11ineightbitprocessorssales,the8051familyofmicrocontrollersisavailableinawidearrayofvariationsfrommanufacturerssuchasIntel,Philips,andSiemens.Thesemanufacturershaveaddednumerousfeaturesandperipheralstothe8051suchasI2Cinterfaces,analogtodigitalconverters,watchdogtimers,andpulsewidthmodulatedoutputs.Variationsofthe8051withclockspeedsupto40MHzandvoltagerequirementsdownto1.5voltsareavailable.Thiswiderangeofpartsbasedononecoremakesthe8051familyanexcellentchoiceasthebasearchitectureforacompanysentirelineofproductssinceitcanperformmanyfunctionsanddeveloperswillonlyhavetolearnthisoneplatform.Thebasicarchitectureconsistsofthefollowingfeatures:aneightbitALU32descreteI/Opins(4groupsof8)whichcanbeindividuallyaccessedtwo16bittimer/countersfullduplexUART6interruptsourceswith2prioritylevels128bytesofonboardRAMseparate64KbyteaddressspacesforDATAandCODEmemoryOne8051processorcycleconsistsoftwelveoscillatorperiods.Eachofthetwelveoscillatorperiodsisusedforaspecialfunctionbythe8051coresuchasopcodefetchesandsamplesoftheinterruptdaisychainforpendinginterrupts.Thetimerequiredforany8051instructioncanbecomputedbydividingtheclockfrequencyby12,invertingthatresultandmultiplyingitbythenumberofprocessorcyclesrequiredbytheinstructioninquestion.Therefore,ifyouhaveasystemwhichisusingan11.059MHzclock,youcancomputethenumberofinstructionspersecondbydividingthisvalueby12.Thisgivesaninstructionfrequencyof921583instructionspersecond.Invertingthiswillprovidetheamountoftimetakenbyeachinstructioncycle(1.085microseconds).中文翻译单片机是指一个集成在一块芯片上的完整计算机系统。尽管他的大部分功能集成在一块小芯片上，但是它具有一个完整计算机所需要的大部分部件：CPU、内存、内部和外部总线系统，目前大部分还会具有外存。同时集成诸如通讯接口、定时器，实时时钟等外围设备。而现在最强大的单片机系统甚至可以将声音、图像、网络、复杂的输入输出系统集成在一块芯片上。单片机也被称为微控制器(Microcontroller)，是因为它