数字时钟外文翻译.docx

数字时钟外文翻译.docx

《数字时钟外文翻译.docx》由会员分享，可在线阅读，更多相关《数字时钟外文翻译.docx（7页珍藏版）》请在冰豆网上搜索。

数字时钟外文翻译

外文资料翻译

LEDusingdigitaltubedigitaldisplayitshigh-brightness,indicatingtheadvantagesofintuitiveintelligenceiswidelyusedinareassuchasequipmentandhouseholdappliances.AT89C52Thisarticledescribesasingle-chipmicrocomputerasthecore,toatotalofanodehigh-brightnessLEDLEDasadisplaycomposedofsevenfiguresshowthatthepracticaldesignofmulti-functionelectronicclocks,theclockshowsaweek,hour,minute,second,itcanbeswitchedtoyear,month,dayshowedthatthewholepointofmusicatthesametimeandfromtimetotimethealarmtimeandotherfunctionscanalsobeusedforelectronicstopwatch.

Clockcircuitistheheartofthecomputer,whichcontrolstherhythmoftheworkofthecomputeristhroughthecompletionofcomplexsequentialcircuitsfunctionindifferentdirections.

Clock,sinceitwasinventedthatdayon,people'sliveshasbecomeanindispensabletool,especiallyinthiseraofefficient,theclockisinthehumanproductionandliving,learningandotherfieldsiswidely.However,withthepassageoftime,peoplenotonlytotherequirementsoftheclockisgettinghigherandhigherprecision,andfunctionalrequirementsfortheclockmoreandmore,theclockhasnotonlyatoolusedtodisplaytime,inmanypracticalapplicationsItalsoneedstobeabletoachievemoreotherfunctions.Featuressuchasalarmclock,calendardisplay,temperaturemeasurementfunction,humiditymeasurements,voltagemeasurements,frequencymeasurements,havebeenunder-voltagealarmfunction.Digitalclockstothepeople'sproductionandlifehasbroughtgreatconvenience,butalsogreatlyexpandsthetimefeaturetheoriginalclocks.Suchasregularauto-alarm,Automatictime-ling,timeprocessautomation,fromtimetotimebroadcast,fromclosed-circuitautomaticlights,oventimerswitch,on-offpowerequipment,electricalandevenavarietyoftimingisautomaticallyenabled,allofwhicharebasedondigitalclocksandwatchesbased.Itcanbesaidthatthedesignofthesignificanceofmulti-functionDigitalClockDigitalClockisnotjustitself,agreatersignificanceofthemulti-functiondigitalclockinanumberofreal-timecontrolsystems.Inmanypracticalapplications,aslongasthedigitalclockcircuitoftheprogramsandhardwaretoacertaindegreeofmodificationcouldbeusefulforreal-timecontrolsystem,whichappliedtotheactualworkandproductionto.Thus,digitalclockandtoexpanditsapplications,hasaverypracticalsignificance.

Withthedevelopmentofhumancivilization,scienceandtechnology,thereistherequestoftheclockcontinuestoimprove.Clockhasnotonlyseenasatooltodisplaythetime,inmanypracticalapplicationsalsoneedtobeabletoachievemoreotherfunctions.High-precision,multifunction,smallsize,lowpowerconsumption,isthedevelopmenttrendofthemodernclock.Inthistrend,digitalclock,multifunctionclockhasbecomethemoderndesignoftheproductionofresearch-leddirection.Thisarticleisbasedonthisdesigndirectionforthecontrolofasingle-chipcoredesignrequirementsofamulti-functionindicatorsinlinewiththedigitalclock.

Thedesignisbasedontheprincipleofsingle-chiptechnologytochipAT89C52single-chipmicrocomputerasthecorecontroller,throughtheproductionofhardwareandsoftwareproceduresforthepreparation,designtoproduceamulti-functionaldigitalclocksystem.Theclocksystemmainlybyclockmodule,alarmmodule,theambienttemperaturedetectionmodule,liquidcrystaldisplaymodule,controlmoduleandthekeyboardsignalpromptedmodule.Systemissimpleandclearuserinterfacethatcan4V~7VDCpowerundernormaloperation.Abletoaccuratelydisplaytime（displayformathh:

mm:

secondsseconds,24-hoursystem）,maybetimetoadjustatanytime,withclocktimesettings,alarmon/off,onlytomakefunctions,wheretheclocktomeasuretheambienttemperatureanddisplayed.Hardwareandsoftwaredesignintotheguidingideology,givefullplaytothesingle-chipfeatures,mostofthefunctionsthroughsoftwareprogrammingtoachieve,thecircuitissimpleandclear,highsystemstability.Atthesametime,theclocksystemalsohasthepowerofsmall,lowcost,andhighlypractical.Systemcomponentsasaresultoflessuse,single-chipoccupiedbytheI/Oportnotmorethan,thesystemhasacertaindegreeofscalability.

Clockdesignisnotheoryofdiscretelogic,programmablelogic,orusingfull-customsilicondevicesofanydigitaldesign,inordertosuccessfullyoperateandreliableclockiscrucial.Poordesignoftheclockinthelimitsoftemperature,voltagedeviationorthemanufacturingprocesswillresultinthecasewrong,anddebuggingdifficult,spendingalot.InthedesignofFPGA/CPLDclockwhenseveraltypesofcommonlyused.Clockcanbedividedintothefollowingfourtypes:

globalclock,clockgating,multi-levellogicclockclockandvolatility.Multi-clocksystemtoincludetheabove-mentionedfourtypesofanycombinationoftheclock.

Nomatterwhatmethodsaretherealcircuitclocktreecannotachievetheidealassumptionthattheclock,sowemustbebasedonanidealclock,theclockrealworktobuildamodeltoanalyzethecircuit,soastomakethecircuitperformanceandthepracticalworkasexpected.Clockintheactualmodel,wehavetoconsiderthespreadofclock-treeskew,verticaljumpandabsolutebiasandotheruncertainties.

Toregister,theclockwasworkingalongthearrivalofthedataterminalwhenitshouldhavebeenstable,soastoensurethattheworkalongthesamplingclocktotheaccuracyofthedata,thisdatapreparationtimethatwecallset-uptime（setuptime）.Datashouldalsobeworkingalongtheclocktomaintainoveraperiodoftime,thisperiodoftimeknownastheholdtime（holdtime）.

Globalclockforadesignproject,theglobalclock（orclocksynchronous）isthesimplestandmostpredictableclock.InthePLD/FPGAdesignoftheclockthebestoptionsare:

byadedicatedglobalclockinputpinsofasinglemasterclock-drivenclockdesignprojectstoeachflip-flop.Aslongaspossibleshouldbeusedinthedesignofglobalclockprojects.PLD/FPGAhasadedicatedglobalclockpins,thedeviceisdirectlyconnectedtoeachregister.Globalclocktoprovidesuchadeviceintheshortestpossibledelaytotheoutputclock.

Clock-gatedinmanyapplications,theentiredesignoftheoveralluseofexternalclockisnotpossibleorpractical.WiththeproductofPLDlogicarrayclock（thatis,theclockisgeneratedbythelogic）,toallowarbitraryfunctionalonealltriggerclock.However,whenyouusethearrayclock,theclockshouldbecarefullyanalyzedthefunction,inordertoavoidglitches.

Usuallyconstitutethearrayclockclock-gated.Clockgatingofteninterfacewiththemicroprocessor,andusedtheaddresstowritetocontrolthepulseline.However,whenusingcombinationofflip-flopwhentheclockfunction,usuallythereisaclock-gated.Ifthefollowingconditions,suchasclockgatingcanbeasreliableasglobalclockwork:

Drivetheclocklogicmustcontainonlyone"and"thedoorora"or"gate.Ifanyadditionalworkinsomestateoflogic,thecompetitionwillbetheburr.

Alogicgateinputastheactualclock,andthelogicgatemustbeofallotherinputastheaddressorcontrollines,inrelationtotheircompliancewiththeestablishmentandmaintenanceofclocktimebound.

Multi-levellogicgeneratedclockwhentheclock-gatinglogicofthecombinationofmorethanone（ormorethantheindividual"and"doorsor"or"gate）,theevidenceofthereliabilityofthedesignoftheprojecthasbecomeverydifficult.Eveniftheprototypeorsimulationresultsshowthatthereisnostaticdangerous,butinfacttheriskmaystillexist.Ingeneral,weshouldnotusemulti-levelcombinationallogictoclocktheflip-flopinthePLDdesign.

Traveling-waveclockclockanotherpopularuseoftraveling-wavecircuitistheclock,thatis,theoutputofaflip-flopusedasaclockinputofanotherflip-flop.Ifcarefuldesign,traveling-waveclockcanbethesameastheglobalclocktoworkreliably.However,thetraveling-waveclockmadefromtimetotimewiththecalculationofthecircuitbecomesverycomplicated.Line-wavetraveling-waveclockflip-flopofthechainhaveagreaterclocktimebetweentheoffsetandexceedtheworstcasetheset-uptime,holdtimeandclocktotheoutputcircuitofthedelay,allowingthesystemtotheactualsloweddown.

Multi-clocksystem,manysystemrequirementswithinthesamemulti-PLDclock.Themostcommonexampleisthetwoasynchronousinterfacesbetweenmicroprocessors,ormicroprocessorsandasynchronouscommunicationchannelinterface.Astheclocksignalbetweenthetworequirementstoestablishandmaintainacertaintime,sothattheaboveapplicationfromtimetotimetheintroductionofadditionalconstraints.Theyalsorequestedthatsomeasynchronoussynchronizationsignal.

Inmanyapplications,onlythesynchronizationofasynchronoussignalsisnotenough,whenthesystemoftwoormorenon-homologousclock,thedataitisdifficulttoestablishandmaintainthetimetobeassuredthatwewillfacethecomplexmatteroftime.Thebestwayistoallnon-homologousclocksynchronization.PLDinternaluseofthelockloop（PLLorDLL）isaverygood,butnotallofPLDwithaPLL,DLL,andchipPLLwithmostexpensive,sounlesstherearespecialrequirements,thegeneraloccasionsPLLcannotusewiththePLD.AtthistimeweneedtotaketoenabletheuseoftheDflip-flop-side,andtheintroductionofahigh-frequencyclock.

采用LED数码管的数字显示以其亮度高、显示直观等优点被广泛应用于智能仪器及家用电器等领域.本文介绍一种以AT89C52单片机为核心,以共阳极高亮度LED数码管作为显示器件组成7位数字显示的实用多功能电子时钟