1、中英文资料翻译题目THEDESCRIPTIONOFMCU系别中德机电学院专业机电一体化技术班级机电1002班学生姓名学号100101239指导教师2012年12月无锡科技职业学院毕业论文中英文翻译1英文原文资料THEDESCRIPTIONOFMCUMCUDESCRIPTIONSCMISALSOKNOWNASMICROCONTROLLERMICROCONTROLLERUNIT,COMMONLYUSEDLETTERSOFTHEACRONYMMCUMCUTHATITWASFIRSTUSEDININDUSTRIALCONTROLONLYASINGLECHIPBYTHECPUCHIPDEVELOPEDF
2、ROMADEDICATEDPROCESSORTHEFIRSTDESIGNISBYALARGENUMBEROFPERIPHERALSANDCPUONACHIPINTHECOMPUTERSYSTEM,SMALLER,MOREEASILYINTEGRATEDINTOACOMPLEXANDDEMANDINGONTHEVOLUMECONTROLDEVICEWHICHINTELSZ80ISTHEFIRSTDESIGNEDINACCORDANCEWITHTHISIDEAPROCESSOR,THENONTHEDEVELOPMENTOFMICROCONTROLLERANDDEDICATEDPROCESSORSH
3、AVEPARTEDWAYSARE8BITMICROCONTROLLEREARLYOR4BITSONEOFTHEMOSTSUCCESSFULISTHEINTEL8031,FORASIMPLE,RELIABLEANDGOODPERFORMANCEWASALOTOFPRAISETHENDEVELOPEDIN8031OUTOFMCS51MCUSYSTEMSSCMSYSTEMSBASEDONTHISSYSTEMUNTILNOWISSTILLWIDELYUSEDWITHTHEINCREASEDREQUIREMENTSOFINDUSTRIALCONTROLFIELD,BEGANA16BITMICROCONT
4、ROLLER,BECAUSETHECOSTISNOTSATISFACTORYBUTHAVENOTBEENVERYWIDELYUSEDAFTER90YEARSWITHTHEGREATDEVELOPMENTOFCONSUMERELECTRONICS,MICROCONTROLLERTECHNOLOGYHASBEENAHUGEINCREASEWITHINTELI960SERIES,ESPECIALLYTHELATERSERIESOFWIDELYUSEDARM,32BITMICROCONTROLLERQUICKLYREPLACEHIGHEND16BITMCUSTATUSANDENTERTHEMAINST
5、REAMMARKETTHETRADITIONAL8BITMICROCONTROLLERPERFORMANCEHAVEBEENTHERAPIDINCREASECAPACITYINCREASECOMPAREDTO80THENUMBEROFTIMESCURRENTLY,HIGHEND32BITMICROCONTROLLERCLOCKEDOVER300MHZ,THEPERFORMANCECATCHINGTHEMID90SDEDICATEDPROCESSOR,WHILETHEAVERAGEMODELPRICESFALLTOONEUSDOLLARS,THEMOSTHIGHEND1MODELONLY10DO
6、LLARSMODERNSCMSYSTEMSARENOLONGERONLYINTHEDEVELOPMENTANDUSEOFBAREMETALENVIRONMENT,ALARGENUMBEROFPROPRIETARYEMBEDDEDOPERATINGSYSTEMISWIDELYUSEDINTHEFULLRANGEOFSCMTHEHANDHELDCOMPUTERSANDCELLPHONESASTHECOREPROCESSINGOFHIGHENDMICROCONTROLLERCANEVENUSEADEDICATEDWINDOWSANDLINUXOPERATINGSYSTEMSSCMISMORESUIT
7、ABLETHANTHESPECIFICPROCESSORUSEDINEMBEDDEDSYSTEMS,SOITWASUPTOTHEAPPLICATIONINFACTTHENUMBEROFSCMISTHEWORLDSLARGESTCOMPUTERMODERNHUMANLIFEUSEDINALMOSTEVERYPIECEOFELECTRONICANDMECHANICALPRODUCTSWILLBEINTEGRATEDSINGLECHIPPHONE,TELEPHONE,CALCULATOR,HOMEAPPLIANCES,ELECTRONIC无锡科技职业学院毕业论文中英文翻译2TOYS,HANDHELD
8、COMPUTERSANDCOMPUTERACCESSORIESSUCHASAMOUSEWITHA12INBOTHTHEDEPARTMENTOFSCMPERSONALCOMPUTERWILLHAVEALARGENUMBEROFSCMINTHEWORKGENERALCARWITHMORETHAN40SCM,COMPLEXINDUSTRIALCONTROLSYSTEMSMAYEVENHAVEHUNDREDSOFSCMINTHESAMETIMEWORKSCMISNOTONLYFAREXCEEDSTHENUMBEROFPCANDOTHERCOMPUTINGTHESUM,OREVENMORETHANTHE
9、NUMBEROFHUMANBEINGSSINGLECHIP,ALSOKNOWNASSINGLECHIPMICROCONTROLLER,ITISNOTCOMPLETEACERTAINLOGICCHIPS,BUTTOACOMPUTERSYSTEMINTEGRATEDINTOACHIPEQUIVALENTTOAMICROCOMPUTER,ANDCOMPUTERTHANJUSTTHELACKOFAMICROCONTROLLERI/ODEVICESGENERALTALKACHIPBECOMESACOMPUTERITSSMALLSIZE,LIGHTWEIGHT,CHEAP,FORTHESTUDY,APPL
10、ICATIONANDDEVELOPMENTOFFACILITIESPROVIDEDATTHESAMETIME,LEARNINGTOUSETHEMCUISTOUNDERSTANDTHEPRINCIPLEANDSTRUCTUREOFTHECOMPUTERTHEBESTCHOICESCMANDTHECOMPUTERFUNCTIONSINTERNALLYWITHSIMILARMODULES,SUCHASCPU,MEMORY,PARALLELBUS,THESAMEEFFECTASWELL,ANDHARDDISKMEMORYDEVICES,ANDDIFFERENTISITSPERFORMANCEOFTHE
11、SECOMPONENTSWERERELATIVELYWEAKMANYOFOURHOMECOMPUTER,BUTTHEPRICEISLOW,USUALLYNOTMORETHAN10YUANYOUCANDOWITHITSOMECONTROLFORACLASSISNOTVERYCOMPLICATEDELECTRICALWORKISENOUGHOFWEAREUSINGAUTOMATICDRUMWASHINGMACHINE,SMOKEHOOD,VCDANDSOONAPPLIANCESWHICHCOULDSEEITSSHADOWITISPRIMARILYASACONTROLSECTIONOFTHECORE
12、COMPONENTSITISANONLINEREALTIMECONTROLCOMPUTER,CONTROLLINEISTHATTHESCENEISNEEDEDISASTRONGERANTIJAMMINGABILITY,LOWCOST,ANDTHISIS,ANDOFFLINECOMPUTERSUCHASHOMEPC,THEMAINDIFFERENCESCMHISTORYSCMWASBORNINTHELATE20THCENTURY,70,EXPERIENCEDSCM,MCU,SOCTHREESTAGESFIRSTMODEL1SCMTHESINGLECHIPMICROCOMPUTERSINGLECH
13、IPMICROCOMPUTERSTAGE,MAINLYSEEKINGTHEBESTOFTHEBESTSINGLEFORMOFEMBEDDEDSYSTEMSARCHITECTURE“INNOVATIONMODEL“SUCCESS,LAYINGTHESCMANDGENERALCOMPUTERCOMPLETELYDIFFERENTPATHOFDEVELOPMENTINTHEOPENROADOFINDEPENDENTDEVELOPMENTOFEMBEDDEDSYSTEMS,INTELCORPORATIONCONTRIBUTED2MCUTHEMICROCONTROLLERMICROCONTROLLERU
14、NITSTAGE,THEMAINDIRECTIONOF无锡科技职业学院毕业论文中英文翻译3TECHNOLOGYDEVELOPMENTEXPANDINGTOMEETTHEEMBEDDEDAPPLICATIONS,THETARGETSYSTEMREQUIREMENTSFORTHEVARIOUSPERIPHERALCIRCUITSANDINTERFACECIRCUITS,HIGHLIGHTTHEOBJECTOFINTELLIGENTCONTROLITINVOLVESTHEAREASASSOCIATEDWITHTHEOBJECTSYSTEM,THEREFORE,THEDEVELOPMENTOFMCUS
15、RESPONSIBILITYINEVITABLYFALLSONELECTRICAL,ELECTRONICSMANUFACTURERSFROMTHISPOINTOFVIEW,INTELFADEDMCUDEVELOPMENTHASITSOBJECTIVEFACTORSINTHEDEVELOPMENTOFMCU,THEMOSTFAMOUSMANUFACTURERSASTHENUMBEROFPHILIPSCORPORATIONPHILIPSCOMPANYINEMBEDDEDAPPLICATIONS,ITSGREATADVANTAGE,THEMCS51SINGLECHIPMICROCOMPUTERFRO
16、MTHERAPIDDEVELOPMENTOFTHEMICROCONTROLLERTHEREFORE,WHENWELOOKBACKATTHEPATHOFDEVELOPMENTOFEMBEDDEDSYSTEMS,DONOTFORGETINTELANDPHILIPSINHISTORYEMBEDDEDSYSTEMSEMBEDDEDSYSTEMMICROCONTROLLERISANINDEPENDENTDEVELOPMENTPATH,THEMCUIMPORTANTFACTORINTHEDEVELOPMENTSTAGE,ISSEEKINGAPPLICATIONSTOMAXIMIZETHESOLUTIONO
17、NTHECHIPTHEREFORE,THEDEVELOPMENTOFDEDICATEDSINGLECHIPSOCTRENDOFTHENATURALFORMASTHEMICROELECTRONICS,ICDESIGN,EDATOOLSDEVELOPMENT,APPLICATIONSYSTEMBASEDONMCUSOCDESIGNHAVEGREATERDEVELOPMENTTHEREFORE,THEUNDERSTANDINGOFTHEMICROCONTROLLERCHIPMICROCOMPUTERCANBE,EXTENDEDTOTHESINGLECHIPMICROCONTROLLERAPPLICA
18、TIONSMCUAPPLICATIONSSCMNOWPERMEATEALLAREASOFOURLIVES,WHICHISALMOSTDIFFICULTTOFINDTRACESOFTHEFIELDWITHOUTSCMMISSILENAVIGATIONEQUIPMENT,AIRCRAFT,ALLTYPESOFINSTRUMENTCONTROL,COMPUTERNETWORKCOMMUNICATIONSANDDATATRANSMISSION,INDUSTRIALAUTOMATION,REALTIMEPROCESSCONTROLANDDATAPROCESSING,EXTENSIVEUSEOFVARIO
19、USSMARTICCARD,CIVILIANLUXURYCARSECURITYSYSTEM,VIDEORECORDER,CAMERA,FULLYAUTOMATICWASHINGMACHINECONTROL,ANDPROGRAMCONTROLLEDTOYS,ELECTRONICPET,ETC,WHICHAREINSEPARABLEFROMTHEMICROCONTROLLERNOTTOMENTIONTHEAREAOFROBOTCONTROL,INTELLIGENTINSTRUMENTS,MEDICALEQUIPMENTWASTHEREFORE,THEMCULEARNING,DEVELOPMENTA
20、NDAPPLICATIONOFTHELARGENUMBEROFCOMPUTERAPPLICATIONSANDINTELLIGENTCONTROLOFTHESCIENTISTS,ENGINEERSTHESINGLECHIPMICROCOMPUTERAT89S52MCUASANEXAMPLE,THEPAIRFORFURTHERDESCRIPTION无锡科技职业学院毕业论文中英文翻译4AT89S51MCUFEATURESCOMPATIBLEWITHMCS51PRODUCTS8KBYTESOFINSYSTEMPROGRAMMABLEISPFLASHMEMORYENDURANCE10,000WRITE/
21、ERASECYCLES40VTO55VOPERATINGRANGEFULLYSTATICOPERATION0HZTO33MHZTHREELEVELPROGRAMMEMORYLOCK256X8BITINTERNALRAM32PROGRAMMABLEI/OLINESTHREE16BITTIMER/COUNTERSEIGHTINTERRUPTSOURCESFULLDUPLEXUARTSERIALCHANNELLOWPOWERIDLEANDPOWERDOWNMODESINTERRUPTRECOVERYFROMPOWERDOWNMODEWATCHDOGTIMERDUALDATAPOINTERPOWERO
22、FFFLAGFASTPROGRAMMINGTIMEFLEXIBLEISPPROGRAMMINGBYTEANDPAGEMODEGREENPB/HALIDEFREEPACKAGINGOPTION1DESCRIPTIONTHEAT89S52ISALOWPOWER,HIGHPERFORMANCECMOS8BITMICROCONTROLLERWITH8KBYTESOFINSYSTEMPROGRAMMABLEFLASHMEMORYTHEDEVICEISMANUFACTUREDUSINGATMELSHIGHDENSITYNONVOLATILEMEMORYTECHNOLOGYANDISCOMPATIBLEWI
23、THTHEINDUSTRYSTANDARD80C51INSTRUCTIONSETANDPINOUTTHEONCHIPFLASHALLOWSTHEPROGRAMMEMORYTOBEREPROGRAMMEDINSYSTEMORBYACONVENTIONALNONVOLATILEMEMORYPROGRAMMERBYCOMBININGAVERSATILE8BITCPUWITHINSYSTEMPROGRAMMABLEFLASHONAMONOLITHICCHIP,THEATMELAT89S52ISAPOWERFULMICROCONTROLLERWHICHPROVIDESAHIGHLYFLEXIBLEAND
24、COSTEFFECTIVESOLUTIONTOMANYEMBEDDEDCONTROLAPPLICATIONSTHEAT89S52PROVIDESTHEFOLLOWINGSTANDARDFEATURES8KBYTESOFFLASH,256BYTESOFRAM,32I/OLINES,WATCHDOGTIMER,TWODATAPOINTERS,THREE16BITTIMER/COUNTERS,ASIXVECTORTWOLEVELINTERRUPTARCHITECTURE,AFULLDUPLEXSERIALPORT,ONCHIPOSCILLATOR,ANDCLOCKCIRCUITRYINADDITIO
25、N,THEAT89S52ISDESIGNEDWITHSTATIC无锡科技职业学院毕业论文中英文翻译5LOGICFOROPERATIONDOWNTOZEROFREQUENCYANDSUPPORTSTWOSOFTWARESELECTABLEPOWERSAVINGMODESTHEIDLEMODESTOPSTHECPUWHILEALLOWINGTHERAM,TIMER/COUNTERS,SERIALPORT,ANDINTERRUPTSYSTEMTOCONTINUEFUNCTIONINGTHEPOWERDOWNMODESAVESTHERAMCONTENTSBUTFREEZESTHEOSCILLATOR,
26、DISABLINGALLOTHERCHIPFUNCTIONSUNTILTHENEXTINTERRUPTORHARDWARERESET2PINDESCRIPTIONVCCSUPPLYVOLTAGEGNDGROUNDPORT0PORT0ISAN8BITOPENDRAINBIDIRECTIONALI/OPORTASANOUTPUTPORT,EACHPINCANSINKEIGHTTTLINPUTSWHEN1SAREWRITTENTOPORT0PINS,THEPINSCANBEUSEDASHIGHIMPEDANCEINPUTSPORT0CANALSOBECONFIGUREDTOBETHEMULTIPLE
27、XEDLOWORDERADDRESS/DATABUSDURINGACCESSESTOEXTERNALPROGRAMANDDATAMEMORYINTHISMODE,P0HASINTERNALPULLUPSPORT0ALSORECEIVESTHECODEBYTESDURINGFLASHPROGRAMMINGANDOUTPUTSTHECODEBYTESDURINGPROGRAMVERIFICATIONEXTERNALPULLUPSAREREQUIREDDURINGPROGRAMVERIFICATIONPORT1PORT1ISAN8BITBIDIRECTIONALI/OPORTWITHINTERNAL
28、PULLUPSTHEPORT1OUTPUTBUFFERSCANSINK/SOURCEFOURTTLINPUTSWHEN1SAREWRITTENTOPORT1PINS,THEYAREPULLEDHIGHBYTHEINTERNALPULLUPSANDCANBEUSEDASINPUTSASINPUTS,PORT1PINSTHATAREEXTERNALLYBEINGPULLEDLOWWILLSOURCECURRENTIILBECAUSEOFTHEINTERNALPULLUPSINADDITION,P10ANDP11CANBECONFIGUREDTOBETHETIMER/COUNTER2EXTERNAL
29、COUNTINPUTP10/T2ANDTHETIMER/COUNTER2TRIGGERINPUTP11/T2EX,RESPECTIVELY,ASSHOWNINTHEFOLLOWINGTABLEPORT1ALSORECEIVESTHELOWORDERADDRESSBYTESDURINGFLASHPROGRAMMINGANDVERIFICATIONTABLE1PORTPINALTERNATEFUNCTIONSP10T2EXTERNALCOUNTINPUTTOTIMER/COUNTER2,CLOCKOUTP11T2EXTIMER/COUNTER2CAPTURE/RELOADTRIGGERANDDIR
30、ECTIONCONTROLP15MOSIUSEDFORINSYSTEMPROGRAMMING无锡科技职业学院毕业论文中英文翻译6P16MISOUSEDFORINSYSTEMPROGRAMMINGP17SCKUSEDFORINSYSTEMPROGRAMMINGPORT2PORT2ISAN8BITBIDIRECTIONALI/OPORTWITHINTERNALPULLUPSTHEPORT2OUTPUTBUFFERSCANSINK/SOURCEFOURTTLINPUTSWHEN1SAREWRITTENTOPORT2PINS,THEYAREPULLEDHIGHBYTHEINTERNALPULLUPSA
31、NDCANBEUSEDASINPUTSASINPUTS,PORT2PINSTHATAREEXTERNALLYBEINGPULLEDLOWWILLSOURCECURRENTIILBECAUSEOFTHEINTERNALPULLUPSPORT2EMITSTHEHIGHORDERADDRESSBYTEDURINGFETCHESFROMEXTERNALPROGRAMMEMORYANDDURINGACCESSESTOEXTERNALDATAMEMORYTHATUSE16BITADDRESSESMOVXDPTRINTHISAPPLICATION,PORT2USESSTRONGINTERNALPULLUPS
32、WHENEMITTING1SDURINGACCESSESTOEXTERNALDATAMEMORYTHATUSE8BITADDRESSESMOVXRI,PORT2EMITSTHECONTENTSOFTHEP2SPECIALFUNCTIONREGISTERPORT2ALSORECEIVESTHEHIGHORDERADDRESSBITSANDSOMECONTROLSIGNALSDURINGFLASHPROGRAMMINGANDVERIFICATIONPORT3PORT3ISAN8BITBIDIRECTIONALI/OPORTWITHINTERNALPULLUPSTHEPORT3OUTPUTBUFFE
33、RSCANSINK/SOURCEFOURTTLINPUTSWHEN1SAREWRITTENTOPORT3PINS,THEYAREPULLEDHIGHBYTHEINTERNALPULLUPSANDCANBEUSEDASINPUTSASINPUTS,PORT3PINSTHATAREEXTERNALLYBEINGPULLEDLOWWILLSOURCECURRENTIILBECAUSEOFTHEPULLUPSPORT3RECEIVESSOMECONTROLSIGNALSFORFLASHPROGRAMMINGANDVERIFICATIONPORT3ALSOSERVESTHEFUNCTIONSOFVARI
34、OUSSPECIALFEATURESOFTHEAT89S52,ASSHOWNINTHEFOLLOWINGTABLETABLE2PORTPINALTERNATEFUNCTIONSP30RXDSERIALINPUTPORTP31TXDSERIALOUTPUTPORTP32INT0EXTERNALINTERRUPT0P33INT1EXTERNALINTERRUPT1P34T0TIMER0EXTERNALINPUTP35T1TIMER1EXTERNALINPUTP36WREXTERNALDATAMEMORYWRITESTROBEP37RDEXTERNALDATAMEMORYREADSTROBERSTR
35、ESETINPUTAHIGHONTHISPINFORTWOMACHINECYCLESWHILETHEOSCILLATORIS无锡科技职业学院毕业论文中英文翻译7RUNNINGRESETSTHEDEVICETHISPINDRIVESHIGHFOR98OSCILLATORPERIODSAFTERTHEWATCHDOGTIMESOUTTHEDISRTOBITINSFRAUXRADDRESS8EHCANBEUSEDTODISABLETHISFEATUREINTHEDEFAULTSTATEOFBITDISRTO,THERESETHIGHOUTFEATUREISENABLEDALE/PROGADDRESS
36、LATCHENABLEALEISANOUTPUTPULSEFORLATCHINGTHELOWBYTEOFTHEADDRESSDURINGACCESSESTOEXTERNALMEMORYTHISPINISALSOTHEPROGRAMPULSEINPUTPROGDURINGFLASHPROGRAMMINGINNORMALOPERATION,ALEISEMITTEDATACONSTANTRATEOF1/6THEOSCILLATORFREQUENCYANDMAYBEUSEDFOREXTERNALTIMINGORCLOCKINGPURPOSESNOTE,HOWEVER,THATONEALEPULSEIS
37、SKIPPEDDURINGEACHACCESSTOEXTERNALDATAMEMORYIFDESIRED,ALEOPERATIONCANBEDISABLEDBYSETTINGBIT0OFSFRLOCATION8EHWITHTHEBITSET,ALEISACTIVEONLYDURINGAMOVXORMOVCINSTRUCTIONOTHERWISE,THEPINISWEAKLYPULLEDHIGHSETTINGTHEALEDISABLEBITHASNOEFFECTIFTHEMICROCONTROLLERISINEXTERNALEXECUTIONMODEPSENPROGRAMSTOREENABLEP
38、SENISTHEREADSTROBETOEXTERNALPROGRAMMEMORYWHENTHEAT89S52ISEXECUTINGCODEFROMEXTERNALPROGRAMMEMORY,PSENISACTIVATEDTWICEEACHMACHINECYCLE,EXCEPTTHATTWOPSENACTIVATIONSARESKIPPEDDURINGEACHACCESSTOEXTERNALDATAMEMORYEA/VPPEXTERNALACCESSENABLEEAMUSTBESTRAPPEDTOGNDINORDERTOENABLETHEDEVICETOFETCHCODEFROMEXTERNA
39、LPROGRAMMEMORYLOCATIONSSTARTINGAT0000HUPTOFFFFHNOTE,HOWEVER,THATIFLOCKBIT1ISPROGRAMMED,EAWILLBEINTERNALLYLATCHEDONRESETEASHOULDBESTRAPPEDTOVCCFORINTERNALPROGRAMEXECUTIONSTHISPINALSORECEIVESTHE12VOLTPROGRAMMINGENABLEVOLTAGEVPPDURINGFLASHPROGRAMMINGXTAL1INPUTTOTHEINVERTINGOSCILLATORAMPLIFIERANDINPUTTO
40、THEINTERNALCLOCKOPERATINGCIRCUITXTAL2OUTPUTFROMTHEINVERTINGOSCILLATORAMPLIFIER3MEMORYORGANIZATIONMCS51DEVICESHAVEASEPARATEADDRESSSPACEFORPROGRAMANDDATAMEMORYUPTO64KBYTESEACHOFEXTERNALPROGRAMANDDATAMEMORYCANBEADDRESSED4TIMER0AND1TIMER0ANDTIMER1INTHEAT89S52OPERATETHESAMEWAYASTIMER0ANDTIMER1INTHEAT89C5
41、1ANDAT89C52FORFURTHERINFORMATIONONTHETIMERSOPERATION,PLEASECLICKONTHEDOCUMENTLINKBELOW无锡科技职业学院毕业论文中英文翻译8HTTP/WWWATMELCOM/DYN/RESOURCES/PROD_DOCUMENTS/DOC4316PDF5TIMER2TIMER2ISA16BITTIMER/COUNTERTHATCANOPERATEASEITHERATIMERORANEVENTCOUNTERTHETYPEOFOPERATIONISSELECTEDBYBITC/T2INTHESFRT2CONTIMER2HASTHR
42、EEOPERATINGMODESCAPTURE,AUTORELOADUPORDOWNCOUNTING,ANDBAUDRATEGENERATORTHEMODESARESELECTEDBYBITSINT2CON,ASSHOWNINTABLE61TIMER2CONSISTSOFTWO8BITREGISTERS,TH2ANDTL2INTHETIMERFUNCTION,THETL2REGISTERISINCREMENTEDEVERYMACHINECYCLESINCEAMACHINECYCLECONSISTSOF12OSCILLATORPERIODS,THECOUNTRATEIS1/12OFTHEOSCI
43、LLATORFREQUENCYTABLE3TIMER2OPERATINGMODESRCLKTCLKCP/RL2TR2MODE00116BITAUTORELOAD01116BITCAPTURE1X1BAUDRATEGENERATORXX0OFFINTHECOUNTERFUNCTION,THEREGISTERISINCREMENTEDINRESPONSETOA1TO0TRANSITIONATITSCORRESPONDINGEXTERNALINPUTPIN,T2INTHISFUNCTION,THEEXTERNALINPUTISSAMPLEDDURINGS5P2OFEVERYMACHINECYCLEW
44、HENTHESAMPLESSHOWAHIGHINONECYCLEANDALOWINTHENEXTCYCLE,THECOUNTISINCREMENTEDTHENEWCOUNTVALUEAPPEARSINTHEREGISTERDURINGS3P1OFTHECYCLEFOLLOWINGTHEONEINWHICHTHETRANSITIONWASDETECTEDSINCETWOMACHINECYCLES24OSCILLATORPERIODSAREREQUIREDTORECOGNIZEA1TO0TRANSITION,THEMAXIMUMCOUNTRATEIS1/24OFTHEOSCILLATORFREQU
45、ENCYTOENSURETHATAGIVENLEVELISSAMPLEDATLEASTONCEBEFOREITCHANGES,THELEVELSHOULDBEHELDFORATLEASTONEFULLMACHINECYCLE6INTERRUPTSTHEAT89S52HASATOTALOFSIXINTERRUPTVECTORSTWOEXTERNALINTERRUPTSINT0ANDINT1,THREETIMERINTERRUPTSTIMERS0,1,AND2,ANDTHESERIALPORTINTERRUPTEACHOFTHESEINTERRUPTSOURCESCANBEINDIVIDUALLY
46、ENABLEDORDISABLEDBYSETTINGORCLEARINGABITINSPECIALFUNCTIONREGISTERIEIEALSOCONTAINSAGLOBALDISABLEBIT,EA,WHICHDISABLESALLINTERRUPTSATONCENOTETHATBITPOSITIONIE6ISUNIMPLEMENTEDUSERSOFTWARESHOULDNOTWRITEA1TOTHISBITPOSITION,SINCEITMAYBEUSEDINFUTUREAT89PRODUCTSTIMER2INTERRUPTISGENERATEDBYTHELOGICALOROFBITST
47、F2ANDEXF2IN无锡科技职业学院毕业论文中英文翻译9REGISTERT2CONNEITHEROFTHESEFLAGSISCLEAREDBYHARDWAREWHENTHESERVICEROUTINEISVECTOREDTOINFACT,THESERVICEROUTINEMAYHAVETODETERMINEWHETHERITWASTF2OREXF2THATGENERATEDTHEINTERRUPT,ANDTHATBITWILLHAVETOBECLEAREDINSOFTWARETHETIMER0ANDTIMER1FLAGS,TF0ANDTF1,ARESETATS5P2OFTHECYCLEINW
48、HICHTHETIMERSOVERFLOWTHEVALUESARETHENPOLLEDBYTHECIRCUITRYINTHENEXTCYCLEHOWEVER,THETIMER2FLAG,TF2,ISSETATS2P2ANDISPOLLEDINTHESAMECYCLEINWHICHTHETIMEROVERFLOWS7OSCILLATORCHARACTERISTICSXTAL1ANDXTAL2ARETHEINPUTANDOUTPUT,RESPECTIVELY,OFANINVERTINGAMPLIFIERTHATCANBECONFIGUREDFORUSEASANONCHIPOSCILLATOREIT
49、HERAQUARTZCRYSTALORCERAMICRESONATORMAYBEUSEDTODRIVETHEDEVICEFROMANEXTERNALCLOCKSOURCE,XTAL2SHOULDBELEFTUNCONNECTEDWHILEXTAL1ISDRIVEN,THEREARENOREQUIREMENTSONTHEDUTYCYCLEOFTHEEXTERNALCLOCKSIGNAL,SINCETHEINPUTTOTHEINTERNALCLOCKINGCIRCUITRYISTHROUGHADIVIDEBYTWOFLIPFLOP,BUTMINIMUMANDMAXIMUMVOLTAGEHIGHANDLOWTIMESPECIFICATIONSMUSTBEOBSERVED8IDLEMODEINIDLEMODE,THECPUPUTSITSELFTOSLEEPWHILEALLTHEONCHIPPERIPHERALSREMAINACTIVETHEMODEISINVOKEDBYSOFTWARETHECONTENTOFTHEONCHIPRAMANDALLTHESPECIALFUNCTIONSREGISTERSREMAINUNCHANGEDDURINGTHISMODETHEIDLEMODECANBETERMINATEDBYANYENABLEDINTERRUPTORBYAHARDWARE
