基于单片机的温湿度控制系统英文文献.docx

基于单片机的温湿度控制系统英文文献12020 年 4 月 19 日文档仅供参考英文文献翻译学 生 姓名刘学毅专业自动化学号0833141分院电子工程分院6 月22020 年 4 月 19 日文档仅供参考1. 外文原文A: Fundamentals of Single-chip MicrocomputerThesingle-chipmicrocomputeris theculminationofboththedevelopmentofthedigitalcomputerandtheintegratedcircuitarguablythetowmost significantinventions of the 20th centuryThesetowtypesofarchitectureare foundin single-chipmicrocomputer.Someemploythesplitprogram/datamemoryoftheHarvardarch itecture,othersfollowthephilosophy,widelyadaptedforgeneral-purposecomputersandmicroprocessors,ofmakingno logicaldistinctionbetweenprogramanddatamemoryasinthePrincetonarchitecture,showninFig.3-5A-2.Ingeneraltermsasingle -chipmicrocomputerischaracterizedbytheincorporationofalltheunitsofacomputer into a single device.Read only memory (ROM)ROM is usually forthe permanent, non-volatilestorageof anapplicationsprogram.Manymicrocomputersandmicrocontrollersareintendedforhigh -volumeapplicationsandhencetheeconomicalmanufactureof12020 年 4月 19 日文档仅供参考thedevicesrequiresthatthecontentsofthe programmemorybecommittedpermanentlyduringthemanufactureof chips .Clearly,thisimpliesarigorousapproachtoROMcoded evelopmentsincechangescannotbemadeaftermanufacture.Thisdevelopmentprocessmayinvolveemulationusingasophisticateddevelopmentsystemwithahardwareemulationcapability as well as the use of powerful software tools.Somemanufacturersprovide additionalROMoptionsby includingintheirrangedevices with(orintendedforusewith)userprogrammablememory.Thesimplestoftheseisusuallydevicewhichcanoperateinamicroprocessormode by usingsome oftheinput/outputlinesasanaddressanddatabusfor accessingexternalmemory.Thistypeofdevicecanbehavefunctionallyasthesinglechipmicrocomputerfromwhichitisderivedalbeit withrestricted I/O and a modified external circuit.TheuseoftheseROMless devicesiscommoneveni nproductioncircuitswherethe volumedoesnotjustifythedevelopmentcostsofcustomon -chipROM2;therecanstillbe asignificantsavinginI/Oandother chipscomparedtoaconventionalmicroprocessorbased22020 年 4月 19 日文档仅供参考circuit.MoreexactreplacementforROMde vicescan beobtainedintheformofvariantswithpiggy-backEPROM(ErasableprogrammableROM)socketsordeviceswithEPROMinsteadofROM。 ThesedevicesarenaturallymoreexpensivethanequivalentROMdevice,butdoprovidecompletecircuitequivalents.EPROMbaseddevicesarealsoextremelyattractiveforlow -volumeapplicationswheretheyprovidetheadvantagesofasingle-chipdevice,intermsofon -chipI/O,etc.,withtheconvenienceofflexibleuserprogrammability.RAMisforthestorageofworkingvariablesanddatausedduringprogramexecution.Thesizeofthis memoryvarieswithdevicetypebutithasthesamecharacteristicwidth(4,8,16bitsetc.)astheprocessor,Specialfunctionregisters,suchasstackpointerortimerregisterareoftenlogicallyincorporatedinto the RAMarea.ItisalsocommoninHardtype microcomputerstotreattheRAMareaasacollectionofregister;itisunnecessarytomakedistinctionbetweenRAMandprocessorregisterasis32020 年 4 月 19日