數(shù)字時鐘外文翻譯

1、外文資料譯LEDusingdigitaltubedigitaldisplayitshigh-brightness,indicatingtheadvantagesofintuitiveintelligenceiswidelyusedinareassuchasequipmentandhouseholdappliances.AT89C52Thisarticledescribesasingle-chipmicrocomputerasthecore,toatotalofanodehigh-brightnessLEDLEDasadisplaycomposedofsevenfiguresshowthatth

2、epracticaldesignofmulti-functionelectronicclocks,theclockshowsaweek,hour,minute,second,itcanbeswitchedtoyear,month,dayshowedthatthewholepointofmusicatthesametimeandfromtimetotimethealarmtimeandotherfunctionscanalsobeusedforelectronicstopwatch.Clockcircuitistheheartofthecomputer,whichcontrolstherhyth

3、moftheworkofthecomputeristhroughthecompletionofcomplexsequentialcircuitsfunctionindifferentdirections.Clock,sinceitwasinventedthatdayon,people'sliveshasbecomeanindispensabletool,especiallyinthiseraofefficient,theclockisinthehumanproductionandliving,learningandotherfieldsiswidely.However,withthep

4、assageoftime,peoplenotonlytotherequirementsoftheclockisgettinghigherandhigherprecision,andfunctionalrequirementsfortheclockmoreandmore,theclockhasnotonlyatoolusedtodisplaytime,inmanypracticalapplicationsItalsoneedstobeabletoachievemoreotherfunctions.Featuressuchasalarmclock,calendardisplay,temperatu

5、remeasurementfunction,humiditymeasurements,voltagemeasurements,frequencymeasurements,havebeenunder-voltagealarmfunction.Digitalclockstothepeople'sproductionandlifehasbroughtgreatconvenience,butalsogreatlyexpandsthetimefeaturetheoriginalclocks.Suchasregularauto-alarm,Automatictime-ling,timeproces

6、sautomation,fromtimetotimebroadcast,fromclosed-circuitautomaticlights,oventimerswitch,on-offpowerequipment,electricalandevenavarietyoftimingisautomaticallyenabled,allofwhicharebasedondigitalclocksandwatchesbased.Itcanbesaidthatthedesignofthesignificanceofmulti-functionDigitalClockDigitalClockisnotju

7、stitself,agreatersignificanceofthemulti-functiondigitalclockinanumberofreal-timecontrolsystems.Inmanypracticalapplications,aslongasthedigitalclockcircuitoftheprogramsandhardwaretoacertaindegreeofmodificationcouldbeusefulforreal-timecontrolsystem,whichappliedtotheactualworkandproductionto.Thus,digita

8、lclockandtoexpanditsapplications,hasaverypracticalsignificance.Withthedevelopmentofhumancivilization,scienceandtechnology,thereistherequestoftheclockcontinuestoimprove.Clockhasnotonlyseenasatooltodisplaythetime,inmanypracticalapplicationsalsoneedtobeabletoachievemoreotherfunctions.High-precision,mul

9、tifunction,smallsize,lowpowerconsumption,isthedevelopmenttrendofthemodernclock.Inthistrend,digitalclock,multifunctionclockhasbecomethemoderndesignoftheproductionofresearch-leddirection.Thisarticleisbasedonthisdesigndirectionforthecontrolofasingle-chipcoredesignrequirementsofamulti-functionindicators

10、inlinewiththedigitalclock.Thedesignisbasedontheprincipleofsingle-chiptechnologytochipAT89C52single-chipmicrocomputerasthecorecontroller,throughtheproductionofhardwareandsoftwareproceduresforthepreparation,designtoproduceamulti-functionaldigitalclocksystem.Theclocksystemmainlybyclockmodule,alarmmodul

11、e,theambienttemperaturedetectionmodule,liquidcrystaldisplaymodule,controlmoduleandthekeyboardsignalpromptedmodule.Systemissimpleandclearuserinterfacethatcan4V7VDCpowerundernormaloperation.Abletoaccuratelydisplaytime(displayformathh:mm:secondsseconds,24-hoursystem),maybetimetoadjustatanytime,withcloc

12、ktimesettings,alarmon/off,onlytomakefunctions,wheretheclocktomeasuretheambienttemperatureanddisplayed.Hardwareandsoftwaredesignintotheguidingideology,givefullplaytothesingle-chipfeatures,mostofthefunctionsthroughsoftwareprogrammingtoachieve,thecircuitissimpleandclear,highsystemstability.Atthesametim

13、e,theclocksystemalsohasthepowerofsmall,lowcost,andhighlypractical.Systemcomponentsasaresultoflessuse,single-chipoccupiedbytheI/Oportnotmorethan,thesystemhasacertaindegreeofscalability.Clockdesignisnotheoryofdiscretelogic,programmablelogic,orusingfull-customsilicondevicesofanydigitaldesign,inordertos

14、uccessfullyoperateandreliableclockiscrucial.Poordesignoftheclockinthelimitsoftemperature,voltagedeviationorthemanufacturingprocesswillresultinthecasewrong,anddebuggingdifficult,spendingalot.InthedesignofFPGA/CPLDclockwhenseveraltypesofcommonlyused.Clockcanbedividedintothefollowingfourtypes:globalclo

15、ck,clockgating,multi-levellogicclockclockandvolatility.Multi-clocksystemtoincludetheabove-mentionedfourtypesofanycombinationoftheclock.Nomatterwhatmethodsaretherealcircuitclocktreecannotachievetheidealassumptionthattheclock,sowemustbebasedonanidealclock,theclockrealworktobuildamodeltoanalyzethecircu

16、it,soastomakethecircuitperformanceandthepracticalworkasexpected.Clockintheactualmodel,wehavetoconsiderthespreadofclock-treeskew,verticaljumpandabsolutebiasandotheruncertainties.Toregister,theclockwasworkingalongthearrivalofthedataterminalwhenitshouldhavebeenstable,soastoensurethattheworkalongthesamp

17、lingclocktotheaccuracyofthedata,thisdatapreparationtimethatwecallset-uptime(setuptime).Datashouldalsobeworkingalongtheclocktomaintainoveraperiodoftime,thisperiodoftimeknownastheholdtime(holdtime).Globalclockforadesignproject,theglobalclock(orclocksynchronous)isthesimplestandmostpredictableclock.Inth

18、ePLD/FPGAdesignoftheclockthebestoptionsare:byadedicatedglobalclockinputpinsofasinglemasterclock-drivenclockdesignprojectstoeachflip-flop.Aslongaspossibleshouldbeusedinthedesignofglobalclockprojects.PLD/FPGAhasadedicatedglobalclockpins,thedeviceisdirectlyconnectedtoeachregister.Globalclocktoprovidesu

19、chadeviceintheshortestpossibledelaytotheoutputclock.Clock-gatedinmanyapplications,theentiredesignoftheoveralluseofexternalclockisnotpossibleorpractical.WiththeproductofPLDlogicarrayclock(thatis,theclockisgeneratedbythelogic),toallowarbitraryfunctionalonealltriggerclock.However,whenyouusethearraycloc

20、k,theclockshouldbecarefullyanalyzedthefunction,inordertoavoidglitches.Usuallyconstitutethearrayclockclock-gated.Clockgatingofteninterfacewiththemicroprocessor,andusedtheaddresstowritetocontrolthepulseline.However,whenusingcombinationofflip-flopwhentheclockfunction,usuallythereisaclock-gated.Ifthefol

21、lowingconditions,suchasclockgatingcanbeasreliableasglobalclockwork:Drivetheclocklogicmustcontainonlyone"and"thedoorora"or"gate.Ifanyadditionalworkinsomestateoflogic,thecompetitionwillbetheburr.Alogicgateinputastheactualclock,andthelogicgatemustbeofallotherinputastheaddressorcontr

22、ollines,inrelationtotheircompliancewiththeestablishmentandmaintenanceofclocktimebound.Multi-levellogicgeneratedclockwhentheclock-gatinglogicofthecombinationofmorethanone(ormorethantheindividual"and"doorsor"or"gate),theevidenceofthereliabilityofthedesignoftheprojecthasbecomeverydi

23、fficult.Eveniftheprototypeorsimulationresultsshowthatthereisnostaticdangerous,butinfacttheriskmaystillexist.Ingeneral,weshouldnotusemulti-levelcombinationallogictoclocktheflip-flopinthePLDdesign.Traveling-waveclockclockanotherpopularuseoftraveling-wavecircuitistheclock,thatis,theoutputofaflip-flopus

24、edasaclockinputofanotherflip-flop.Ifcarefuldesign,traveling-waveclockcanbethesameastheglobalclocktoworkreliably.However,thetraveling-waveclockmadefromtimetotimewiththecalculationofthecircuitbecomesverycomplicated.Line-wavetraveling-waveclockflip-flopofthechainhaveagreaterclocktimebetweentheoffsetand

25、exceedtheworstcasetheset-uptime,holdtimeandclocktotheoutputcircuitofthedelay,allowingthesystemtotheactualsloweddown.Multi-clocksystem,manysystemrequirementswithinthesamemulti-PLDclock.Themostcommonexampleisthetwoasynchronousinterfacesbetweenmicroprocessors,ormicroprocessorsandasynchronouscommunicati

26、onchannelinterface.Astheclocksignalbetweenthetworequirementstoestablishandmaintainacertaintime,sothattheaboveapplicationfromtimetotimetheintroductionofadditionalconstraints.Theyalsorequestedthatsomeasynchronoussynchronizationsignal.Inmanyapplications,onlythesynchronizationofasynchronoussignalsisnote

27、nough,whenthesystemoftwoormorenon-homologousclock,thedataitisdifficulttoestablishandmaintainthetimetobeassuredthatwewillfacethecomplexmatteroftime.Thebestwayistoallnon-homologousclocksynchronization.PLDinternaluseofthelockloop(PLLorDLL)isaverygood,butnotallofPLDwithaPLL,DLL,andchipPLLwithmostexpensi

28、ve,sounlesstherearespecialrequirements,thegeneraloccasionsPLLcannotusewiththePLD.AtthistimeweneedtotaketoenabletheuseoftheDflip-flop-side,andtheintroductionofahigh-frequencyclock.采用LED數(shù)碼管的數(shù)字顯示以其亮度高、顯示直觀等優(yōu)點被廣泛應(yīng)用于智能儀器及家用電器等領(lǐng)域.本文介紹一種以AT89C52單片機為核心以共陽極高亮度LED數(shù)碼管作為顯示器件組成7位數(shù)字顯示的實用多功能電子時鐘的設(shè)計,該時鐘可顯示星期、時、分、秒,

29、也可切換為年、月、日顯示,同時具有整點音樂報時及定時鬧鐘等功能,也可作電子秒表使用.時鐘電路是計算機的心臟,它限制著計算機的工作節(jié)奏就是通過復(fù)雜的時序電路完成不同的指令功能的.時鐘,自從它被創(chuàng)造的那天起,就成為人們生活中必不可少的一種工具,尤其是在現(xiàn)在這個講究效率的年代,時鐘更是在人類生產(chǎn)、生活、學(xué)習(xí)等多個領(lǐng)域得到廣泛的應(yīng)用.然而隨著時間的推移,人們不僅對于時鐘精度的要求越來越高,而且對于時鐘功能的要求也越來越多,時鐘已不僅僅是一種用來顯示時間的工具,在很多實際應(yīng)用中它還需要能夠?qū)崿F(xiàn)更多其它的功能.諸如鬧鐘功能、日歷顯示功能、溫度測量功能、濕度測量功能、電壓測量功能、頻率測量功能、過欠壓報警功

30、能等.鐘表的數(shù)字化給人們的生產(chǎn)生活帶來了極大的方便,而且大大地擴展了鐘表原先的報時功能.諸如定時自動報警、按時自動打鈴、時間程序自動限制、定時播送、自動起閉路燈、定時開關(guān)烘箱、通斷動力設(shè)備、甚至各種定時電氣的自動啟用等,所有這些,都是以鐘表數(shù)字化為根底的.可以說,設(shè)計多功能數(shù)字時鐘的意義已不只在于數(shù)字時鐘本身,更大的意義在于多功能數(shù)字時鐘在許多實時限制系統(tǒng)中的應(yīng)用.在很多實際應(yīng)用中,只要對數(shù)字時鐘的程序和硬件電路加以一定的修改,便可以得到實時限制的實用系統(tǒng),從而應(yīng)用到實際工作與生產(chǎn)中去.因此,研究數(shù)字時鐘及擴大其應(yīng)用,有著非?，F(xiàn)實的意義.隨著人類科技文明的開展,人們對于時鐘的要求在不斷地提升.

31、時鐘已不僅僅被看成一種用來顯示時間的工具,在很多實際應(yīng)用中它還需要能夠?qū)崿F(xiàn)更多其它的功能.高精度、多功能、小體積、低功耗,是現(xiàn)代時鐘開展的趨勢.在這種趨勢下,時鐘的數(shù)字化、多功能化已經(jīng)成為現(xiàn)代時鐘生產(chǎn)研究的主導(dǎo)設(shè)計方向.本文正是基于這種設(shè)計方向,以單片機為限制核心,設(shè)計制作一個符合指標(biāo)要求的多功能數(shù)字時鐘.本設(shè)計基于單片機技術(shù)原理,以單片機芯片AT89C52作為核心限制器,通過硬件電路的制作以及軟件程序的編制,設(shè)計制作出一個多功能數(shù)字時鐘系統(tǒng).該時鐘系統(tǒng)主要由時鐘模塊、鬧鐘模塊、環(huán)境溫度檢測模塊、液晶顯示模塊、鍵盤限制模塊以及信號提示模塊組成.系統(tǒng)具有簡單清楚的操作界面,能在4V7V直流電源下

32、正常工作.能夠準(zhǔn)確顯示時間顯示格式為時時：分分：秒秒,24小時制,可隨時進行時間調(diào)整,具有鬧鐘時間設(shè)置、鬧鐘開/關(guān)、止鬧功能,能夠?qū)r鐘所在的環(huán)境溫度進行測量并顯示.設(shè)計以硬件軟件化為指導(dǎo)思想,充分發(fā)揮單片機功能,大局部功能通過軟件編程來實現(xiàn),電路簡單明了,系統(tǒng)穩(wěn)定性高.同時,該時鐘系統(tǒng)還具有功耗小、本錢低的特點,具有很強的實用性.由于系統(tǒng)所用元器件較少,單片機所被占用的I/O不多,因此系統(tǒng)具有一定的可擴展性.時鐘設(shè)計無淪是用離散邏輯、可編程邏輯,還是用全定制硅器件實現(xiàn)的任何數(shù)字設(shè)計,為了成功地操作,可靠的時鐘是非常關(guān)鍵的.設(shè)計不良的時鐘在極限的溫度、電壓或制造工藝的偏差情況下將導(dǎo)致錯誤的行為

33、,并且調(diào)試?yán)щy、花銷很大.在設(shè)計FPGA/CPLD時通常采用幾種時鐘類型.時鐘可分為如下四種類型：全局時鐘、門控時鐘、多級邏輯時鐘和波動式時鐘.多時鐘系統(tǒng)能夠包括上述四種時鐘類型的任意組合.無論采用何種方式,電路中真實的時鐘樹也無法到達假定的理想時鐘,因此我們必須依據(jù)理想時鐘,建立一個實際工作時鐘模型來分析電路,這樣才可以使得電路的實際工作效果和預(yù)期的一樣.在實際的時鐘模型中,我們要考慮時鐘樹傳播中的偏斜、跳變和絕對垂直的偏差以及其它一些不確定因素.對于存放器而言,當(dāng)時鐘工作沿到來時它的數(shù)據(jù)端應(yīng)該已經(jīng)穩(wěn)定,這樣才能保證時鐘工作沿采樣到數(shù)據(jù)的正確性,這段數(shù)據(jù)的預(yù)備時間我們稱之為建立時間(setuptime).數(shù)據(jù)同樣應(yīng)該在時鐘工作沿過去后保持一段時間,這段時間稱為保持時間(holdtime).全局時鐘對于一個