DISTRIBUTEDTEMPERATURESENSORINTHEHUMANLIVINGENVIRONMENT,TEMPERATUREPLAYINGANEXTREMELYIMPORTANTROLE。NOMATTERWHEREYOULIVE,ENGAGEDINANYWORK,EVERPRESENTDEALTWITHTEMPERATUREUNDERSINCETHE18THCENTURY,INDUSTRYSINCETHEINDUSTRIALREVOLUTIONTOWHETHERCANMASTERSENDEXHIBITIONHASTHEABSOLUTETEMPERATURETOUCHINMETALLURGY,STEEL,PETROCHEMICAL,CEMENT,GLASS,MEDICINEINDUSTRYANDSOON,CANSAYALMOSTEIGHTYPERCENTOFINDUSTRIALDEPARTMENTSHAVETOCONSIDERTHEFACTORSWITHTEMPERATURETEMPERATUREFORINDUSTRIALSOIMPORTANT,THUSPROMOTINGTHEDEVELOPMENTOFTHETEMPERATURESENSORMAJORGENERALTHROUGHTHREESENSORDEVELOPMENTPHASEANALOGINTEGRATEDTEMPERATURESENSORTHESENSORISTAKENWITHSILICONSEMICONDUCTORINTEGRATEDWORKMANSHIP,THEREFOREALSOCALLEDSILICONSENSORORMONOLITHICINTEGRATEDTEMPERATURESENSORSUCHSENSINGINSTRUMENTSHAVESINGLEFUNCTIONONLYMEASURINGTEMPERATURE,TEMPERATUREMEASUREMENTERRORISSMALLER,PRICELOW,FASTRESPONSE,THETRANSMISSIONDISTANCE,SMALLVOLUME,MICROCONSUMPTIONELECTRONICETC,SUITABLEFORLONGDISTANCEMEASUREMENTTEMPERATURE,TEMPERATURECONTROL,DONOTNEEDTOUNDERTAKENONLINEARCALIBRATION,PERIPHERALCIRCUITISSIMPLEITISCURRENTLYTHEMOSTCOMMONAPPLICATIONATHOMEANDABROAD,ANINTEGRATEDSENSOR。TYPICALPRODUCTSHAVEAD590AD592,TMP17,LM135,ETCJANALOGINTEGRATEDTEMPERATURECONTROLLERANALOGINTEGRATEDTEMPERATURECONTROLLERMAINLYINCLUDETEMPERATURECONTROLSWITCH,PROGRAMMABLETEMPERATURECONTROLLER,ATYPICALPRODUCTHAVELM56,AD22105ANDMAX6509SOMEINCREASESTRENGTHTYPEINTEGRATEDTEMPERATURECONTROLLERFOREXAMPLETC652/653ALSOCONTAINSTHEA/DCONVERTERANDCUREGOODSEQUENCE,THISPROCESSWITHTHEINTELLIGENTTEMPERATURESENSORSOMESIMILARITIESBUTITISNOTITSSYSTEM,WORKBYMICROPROCESSINGDEVICECONTROL,THISISTHEMAINDIFFERENCEBETWEENINTELLIGENTTEMPERATURESENSORINTELLIGENTTEMPERATURESENSORALSOCALLEDDIGITALTEMPERATUREDEGREESSENSORISINTHEMID1990SLAUNCHITISMICROELECTRONICSTECHNOLOGY,COMPUTERTECHNOLOGYANDTHEDYNAMICTESTINGTECHNOLOGYATECRYSTALLIZATIONINTELLIGENTTEMPERATURESENSORINTERNALCONTAINTEMPERATURESENSOR,A/DCONVERTER,SIGNALPROCESSOR,MEMORYORREGISTERSANDINTERFACECIRCUITSOMEPRODUCTSSTILLTAKEMULTIPLEXER,CENTRALCONTROLSYSTEMDEVICECPU,RANDOMACCESSMEMORYRAMANDREADONLYMEMORYROMINTELLIGENTTEMPERATURESENSORISCHARACTERISTICOFTEMPERATUREDATAANDRELEVANTCANOUTPUTTHETEMPERATURECONTROLOFTHEQUANTITY,ADAPTATIONVARIOUSMICROCONTROLLERMCUTHEDEVELOPMENTTRENDOFTHETEMPERATURESENSORINTHE21STCENTURY,THETEMPERATURESENSORISHEADEDINHIGHPRECISION,MULTIFUNCTION,BUS,STANDARDIZATION,HIGHRELIABILITYANDSAFETY,DEVELOPMENTOFVIRTUALSENSORANDNETWORKSENSOR,RESEARCHMONOLITHICTEMPERATUREMEASURINGSYSTEMANDOTHERHIGHTECHDIRECTIONDEVELOPRAPIDLYSENSORSINTHEAPPLICATIONTEMPERATURECONTROLLINGSYSTEMCURRENTMARKETEXISTSMAINLYSINGLEPOINTANDMORETWOTEMPERATUREMEASUREMENTFORSINGLEPOINTTEMPERATUREFOUNDMENTINSTRUMENT,MAINLYADOPTSTHETRADITIONALANALOGINTEGRATEDTEMPERATURESENSOR,WHICHHEATRESISTANCE,THERMOCOUPLESENSORSMEASURINGACCURACY,HIGHMEASUREMENTRANGE,ANDGOTTHEGENERALAPPLICATIONTHISPRODUCTISTEMPERATUREMEASURINGRANGE200MOSTLYBETWEEN800,RESOLUTION12TH,ANDLEASTDISTINGUISHABLETEMPERATUREIN0001001BETWEENCABINLEDDISPLAYMODULE,SHOWSRANGINGFROM4TO16SOMEINSTRUMENTSALSOHASMEMORYFUNCTION,CANSTORESEVERALHUNDREDTOAFEWTHOUSANDSETSOFDATATHISINSTRUMENTCANBEVERYGOODMEETASINGLEUSERSINGLEPOINTMEASUREMENTNEEDSMORETEMPERATUREMEASUREMENT,RELATIVEANDSINGLEPOINTMEASUREMENTPRECISIONHASCERTAINGAP,ALTHOUGHREALIZEDTHEMULTICHANNELTEMPERATUREMEASUREMENTANDCONTROL,BUTTHEPRICEISEXPENSIVEINVIEWOFTHEPRESENTMARKETSITUATION,PROPOSEDTHISTOPICCANSATISFYREQUIREMENTS,SCALABLEANDCOSTEFFECTIVESINGLECHIPMULTICHANNELTEMPERATUREMEASURINGSYSTEMTHROUGHTHEFIRSTTEMPERATURESENSORDS18B20ACQUISITION,ANDTHENTHROUGHTHEC51SCMPROCESSINGANDDISPLAYEDONTHEDIGITALTUBE,CANBECOLLECTEDINDOORORAGREENHOUSEAROUNDINDIFFERENTLOCATIONSOFTHETEMPERATURE,WITHFOURDIGITALTUBETODISPLAYTHEFIRSTDIGITALPIPEDISPLAYACQUISITIONISWHICHWAY,WHICHCHANNELTHREEDIGITALPIPEDISPLAYAFTERTHEACQUISITIONCHANNELBYTEMPERATURE,ACCURATETO01DEGREESAT89C51ISA4KBYTESFLASHMEMORYERASABLEPROGRAMMABLEANDFPEROMFLASHFORTHECAMPAIGNSWITHLOWVOLTAGE,HIGHPERFORMANCECMOSEIGHTMICROPROCESSORS,COMMONLYKNOWNASTHEMICROCONTROLLERAT89C2051ISA2KBYTESWITHFLASHMEMORYCANBEERASEDPROGRAMMABLEREADONLYMEMORY,SCMCANERASEREADONLYMEMORYCANBEREPEATEDERASED1000TIMESTHISDEVICEADOPTSATMELHIGHDENSITYNONVOLATILEMEMORYMANUFACTURINGTECHNOLOGYMANUFACTURING,ANDINDUSTRIALSTANDARDMCS51INSTRUCTIONSETANDOUTPUTTUBECOMPATIBLEDUETOTHEMULTIFUNCTIONAL8BITSCPUANDWILLBEFLASHINGONSINGLECHIPCOMBINATIONOFMEMORY,ATMELAT89C51ISAKINDOFHIGHEFFICIENTMICROCONTROLLER,AT89C2051ISASTREAMLINEDVERSIONAT89C51MICROCONTROLLERASMANYEMBEDDEDCONTROLSYSTEMARRANGEAPPEARANCEANDPINASSHOWNINFIGURE“12“SHOWN12AT89C51PINSFIGUREMAJORFEATURESANDMCS51COMPATIBLE4KBYTESPROGRAMMABLEFLASHMEMORYLIFE1000WRITE/WIPECYCLEDATARETENTIONTIME10YEARSTHESTATICJOB0HZ24MHZLEVEL3PROGRAMMEMORYLOCK128X8BITSINTERNALRAM32PROGRAMMABLEI/OLINESTWO16TIMER5INTERRUPTSOURCEPROGRAMMABLESERIALCHANNELSLOWPOWERCONSUMPTIONOFIDLEANDPOWERLOSTMODEPIECEINSIDEOSCILLATORANDCLOCKCIRCUITTUBEFEETEXPLAINSVCCPOWERSUPPLYVOLTAGEGNDGROUNDEDP0MOUTHP0MOUTHAEIGHTLEAKLEVELTWOWAYI/OMOUTHOPEN,EVERYFOOTCANABSORB8TTLGAT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蕩器和時鐘電路管腳說明VCC供電電壓。GND接地。P0口P0口為一個8位漏級開路雙向I/O口，每腳可吸收8TTL門電流。當P0口的管腳第一次寫1時，被定義為高阻輸入。P0能夠用于外部程序數據存儲器，它可以被定義為數據/地址的第八位。在FIASH編程時，P0口作為原碼輸入口，當FIASH進行校驗時，P0輸出原碼，此時P0外部必須被拉高。P1口P1口是一個內部提供上拉電阻的8位雙向I/O口，P1口緩沖器能接收輸出4TTL門電流。P1口管腳寫入1后，被內