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可编程控制器技术讨论与未来发展学生姓名：******所在院系：******所学专业：******导师姓名：******完成时间：******1外文资料PLCtechniquediscussionandfuturedevelopmentWiththedevelopmentofthetimes,today'stechnologyismaturing,competitionintensified;relyonmanualoperationdoesnotsatisfythecurrentindustryoutlook,thereisnoguaranteeofhigherqualityrequirementsandhigh-techcorporateimage.Peoplesawintheproductionpractice,automationtobringgreatconvenienceandproductqualityassurance,butalsoreducethelaborintensity,reducingthestaffontheestablishmentinmanycomplexproductionprocessisdifficulttoachievetargetcontrol,theoveralloptimization,optimaldecision-making,skilledoperatives,techniciansorspecialists,managerscaneasilydetermineandoperateit,youcangetsatisfactoryresults.artificialintelligenceresearchistheuseofcomputerstoachievethetarget,theanalogTheseintelligentbehavior,throughcoordinationofthehumanbrainandacomputertocombinehumanmodelsforsolvingverycomplexproblemoffindingthebestway.PLC'smostimportantfeatureis:electricalengineerelectricalhardwarenolongerspendtoomuchscheming,aslongasthebuttonswitchorsensorinputconnectedtothePLCinputpointwillsolvetheproblembyconnectingtheoutputpointcontactsorrelaytocontrolthepowerofthebootdevice,andsmallpoweroutputdevicescanbeconnecteddirectly.ContainedwithinthePLChavingacentralprocessoroftheCPU,andwithanexternalI/OportexpansionI/Ointerfaceandthememoryaddressesofthreemajorcomponents,CPUcoreisformedbyoneormoreaccumulators,whichhavethelogicalmathcapabilities,andcanreadthecontentsoftheprogrammemorytodrivethroughthecalculationofthecorrespondingmemoryandI/Ointerface;I/Oporttotheinternalaccumulatorandexternalinputandoutputsystemstogether,andtherelevantdatastoredintheprogrammemoryordatamemory;memorycanbeI/Oportinputdatastoredinmemoryandtransferredtotheaccumulatoratwork,andI/Ointerfaces,memorysub-ROMprogrammemoryanddatamemoryRAM,ROMdatacanbepermanentlystoredinmemory,CPUandRAMonlyasatemporarycalculatedusingthecalculationbufferspace.PLCimmunityisextremelygood,wedonothavetocareaboutthelifeandworkofitsharshoccasions,alloftheseissuesarenolongerthesubjectofourfailure,andleftusisconcernedwithhowtotakeadvantageofthePLC'sinternalresourcesto2strengthenourabilitytocontrolthedevice,sothatourequipmentismoreflexible.PLClanguageisnotwhatweimaginetheassemblylanguageorClanguageprogramming,insteadofusingtheexistingrelaycontroloftheladder,makinganelectricalengineerinthepreparationoftheprogramisveryeasytounderstandthelanguageofthePLC,andmanynon-Electricalprofessionalsandin-depthunderstandingofthePLCquickly.PLCcommunicationhasbecomeincreasinglyreflectitsvalue,inthecommunicationbetweenthePLCandthePLC,throughinformation,communicationanddatasharingtoensurecoordinationbetweendevices,hasreachedacomplementaryeffect.PLCdatatransferonlytheinternaldatatotheothersideofaconsecutiveaddresses,wecalleditatable,theotherPLCbyreadingdatainthetabletooperate.Thetransmissionofinformationhasserialandparallelportlinesofthepoints:theusualPLCis8machine,ofcourse,thereare16machines.Whenwesendthedatatransmissioncanbeaonetotheother,youcanalsoeight8-bitsenddatatoeachother,oneandeightdifferenceiswhatwecalltheserialportandparallelporttosenddatatosenddata.Serialportspeedisrelativelyslow,butaslongastwoorthreeportlineswillsolvetheproblem,andcanusethephonelineforremotecontrol.Theparallelporttransmissionspeedisveryfast,whichis256timestheserialport,ashortdistanceadvantage,becauseitisTTLlevel,generallylimitedtoonemeterrange,itdoesnotapplytolong-distancedatatransmission,sothecostistooexpensive.Manycases,wealwaysliketousestringandconversionchipfortransmission,inwhichcasewedonotneedtobeoverlycomplexregisterset,anddirectdatatransferinstructionthroughtheexchangeofdata,butnotaveryviablecommunicationapproach,becausethetransmitdatawhenthePLCmusthavebeenwaitingfortheothersideofyourdataoutput,itcannotdootherwork.Whenyouarereadingabook,whenyouhearsomeoneknockingatthedoor,youstopthehandsofthings,playtoopenthedoor,andknockonthedoorwithadialogue,thistimethephonerings,youanswerthephoneschematicallyintakecalls,backtoknockonthedoortocontinuewiththedialogue,hasbeencompleted,youthencontinuetoreadyourbook,inwhichcasewecallitaninterrupt,ithasauthority,alsohaspriority,PLChavethiskindoffunctionality.Itischaracterizedbytheoperationofthedeviceisthatwemayencounterduringemergencyincidents,wehavetostopimmediatelythetaskathand,todealwithmoreimportantthings,thissituationisthat3weoftenencounter,PLCtoperformtasksinanemergency,alwaysfirstsavethecurrentstate,suchastheprogram'saddress,CPUaccumulatordata,likewhenwewenttoopenthedoortonotewearelookingatthefirstfewpagesofthebookorsimplytomakeasign,becausewewillhavetocontinuetobefollowedtoseethebackofthebook.CPUalwaysinaccordancewiththewishesweshoulddo,butyougiveitawrongthing,itwilldothesame,whichwemustpayattention.Interruptisnottheonlyone,sometimesexistseveralinterrupt,theinterruptprioritylevelwiththemaccordingtotheperson'srequesttoperformhigher-levelinterrupts.Thiswillformtheinterruptinterruptinterruptnesting.Ofcourse,thelevelofdisruptioninsidethePLCCPUbasedonavarietyofresource-related,butalsowiththe