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1、word文档整理分享1、外文原文A:FundamentalsofSingle-chipMicrocomputerThesingle-chipmicrocomputeristheculminationofboththedevelopmentofthedigitalcomputerandtheintegratedcircuitarguablythetowmostsignificantinventionsofthe20thcentury[1].Thesetowtypesofarchitecturearefoundinsingle-chipmicrocomputer.

2、Someemploythesplitprogram/datamemoryoftheHarvardarchitecture,showninFig.3-5A-1,othersfollowthephilosophy,widelyadaptedforgeneral-purposecomputersandmicroprocessors,ofmakingnologicaldistinctionbetweenprogramanddatamemoryasinthePrincetonarchitecture,showninFig.3-5A-2.Ingeneraltermsasi

3、ngle-chipmicrocomputerischaracterizedbytheincorporationofalltheunitsofacomputerintoasingledevice,asshowninFig3-5A-3.ProgrammemoryInput&OutputunitCPUDatamemoryFig.3-5A-1AHarvardtypeInput&OutputunitCPUmemoryFig.3-5A-2.AconventionalPrincetoncomputer参考资料word文档整理分享Timer/CounterSystemcloc

4、kExternalTimingcomponentsSerialI/OROMResetPrarallelI/ORAMInterruptsCPUPowerFig3-5A-3.PrincipalfeaturesofamicrocomputerReadonlymemory(ROM).ROMisusuallyforthepermanent,non-volatilestorageofanapplicationsprogram.Manymicrocomputersandmareintendedforhigh-volumeapplicationsandhencetheecon

5、omicalmanufactureofthedevicesrequiresthatthecontentsoftheprogrammemorybecommittedpermanentlyduringthemanufactureofchips.Clearly,thisimpliesarigorousapproachtoROMcodedevelopmentsincechangescannotbemadeaftermanufacture.Thisdevelopmentprocessmayinvolveemulationusingasophisticateddevelo

6、pmentsystemwithahardwareemulationcapabilityaswellastheuseofpowerfulsoftwaretools.SomemanufacturersprovideadditionalROMoptionsbyincludingintheirrangedeviceswith(orintendedforusewith)userprogrammablememory.Thesimplestoftheseisusuallydevicewhichcanoperateinamicroprocessormodebyusingsom

7、eoftheinput/outputlinesasanaddressanddatabusforaccessingexternalmemory.Thistypeofdevicecanbehavefunctionallyasthesinglechipmicrocomputerfromwhichitis参考资料word文档整理分享derivedalbeitwithrestrictedI/Oandamodifiedexternalcircuit.Theuseofthesedevicesiscommoneveninproductioncircuitswherethevo

8、lumedoesnotjustifyt