MMC(SD)卡技术手册

1MultiMediaCardsMMCASeminarTechnicalPresentationTaipei,Sept.20032Contents-MultiMediaCardArchitecture-MultiMediaCardCommand-MultiMediaCardInitialization-MultiMediaCardRegister3MultiMediaCardArchitecture4Systemfeature-1-MultipleMultiMediaCardcanbeconnectedtoonephysicalbus.30pcsmax.-Variableclockfrequency0to20MHz(upto10cardsformaxdatarate)-Transferdatasizeischangeable.1byteto2,048bytes(forRead)5Systemfeature-2-SystemvoltagerangeHighvoltageMMC:2.7-3.6vLowvoltageMMC:1.65-1.95v,2.7-3.6v-TwoformfactorsNormalsize:24mmx32mmx1.4mmReducedsize:24mmx18mmx1.4mmMMCRS-MMCRS-MMCadapter6These2modesareindependentineach.AfterCardispoweredon,cardexecutestheinitializationprocedureandthemodeissetwiththelevelof#1pinatthepoweredon.Tochangethemodeanotherpowercycleisrequired.Systemfeature-3Twooperationmode-MMCmode(Primary)3pinsserialbus-SPImode(Secondary)3pinsserialbus+Chipselectpin71234567NameRSVCMDVSS1VDD1CLKVSS2DAT1PinNo.234567DescriptionGNDVCCGNDReservedCommand/ResponseClockDatain/outCSDIVSSVDDSCLKVSS2DONameGNDVCCGNDDataoutDatainChipselectClockDescriptionMMCmodeSPImodePindescriptionAfterpoweroncardissetasMMCmodeasdefault.81PinNo.NameTypeDescriptionRSVCMDVSS1VDD1CLKVSS2DAT234567CSDIVSSVDDSCLKVSS2DOInputInputGNDVCCGNDNCPush-pull/Open-drainI/OGNDVCCGNDInputReservedCommand/ResponseClockDatain/outDataoutDatainChipselectClockPinArrangement3pinsserialbus(CLK,CMD,DAT)(CLK,DI,DO&CS)0-20MHz0-20MHzCardisselectedbytheCSsignal.MMCI/FSPII/FCardisselectedbyMMCbusprotocol.Hostsendstherelativecardaddresstoselectthecardwhichhasthesameone.Singleblockaccess,MultipleblockaccessSingleblockaccessMultiblockaccess(fromVer.3.1)StreamaccessComparisonofsystemspecificationPush-pullI/ONameTypeDescriptionPush-pullInputPush-pullOutput3pinsserialbus+CSInterfaceFrequencyAccessmodeCardSelectionComparisontableofMMCandSPImode9Generalfunctiondescription#CardIdentificationmode#Thehostwillbeincardidentificationmodeafterresetandwhileitislookingfornewcardsonthebus.CardwillbeinthismodeafterresetuntiltheSET_RCAcommand(CMD3)isreceived.#Datatransfermode#CardwillenterdatatransfermodeonceanRCAisassignedtothem.Thehostwillenterdatatransfermodeafteridentifyingallthecardsonthebus.10•ControlCMDsignal/DATsignalsynchronizedwithCLKsignal.•CMDpinisthebi-directionalpin.AtfirstthecommandsignalisinputtothecardthroughCMDlinebyhost.ThenresponddataisoutputtothehostthroughCMDlinebycard.•DATpinisthebi-directionalpin.ReaddataisoutputtohostthroughDATlinebycard.WritedataisinputtothecardthroughCMDlinebyhost.•Thereisnochipselectpin.•Singleblockaccess,Multipleblockaccessandstreamaccessaresupported.MMC(MultiMediaCard)modeCMDHostDATCLK1234567VccRcsRDATRCMD11CMDDATDATACommandCommandResponse(1)Hosttocard(2)Cardtohost(3)DataoutCMDDATDATACommandCommandResponseReadWrite(1)Hosttocard(1)Hosttocard(2)Cardtohost(3)Datain(1)HosttocardMMCmodedatatransfer12•ControlCMDsignal/DATsignalsynchronizedwithCLKsignal.•DataisinputtoDI(datain)pinandoutputfromDO(dataout)pin.•ThereisCSpinforchipselect.•SingleblockaccessandMultiblockaccessissupported.SPImodeDoutHostCLKDin1234567VccRcsRDINRDOUTCS13DataInDataOutDATACommandCommandResponseDataInDataOutDATACommandCommandResponseReadWrite(1)Hosttocard(2)Cardtohost(3)Dataout(1)Hosttocard(1)Hosttocard(2)Cardtohost(3)Datain(1)HosttocardSPImodedatatransfer14zExampleofstreamreadDataread/writefromthebeginningtotheendwithonlyonecommand.Dataread/writeofthesingleblockwithcommand.„StreamaccesscommandzExampleofmultipleblockread„MultipleblockaccesscommandDataread/writeofthemultipleblockwithonlyonecommand.CRC*interruptionisoccurredattheendofeachblock.*CRC:CyclicredundancycodezExampleofsingleblockread„SingleblockaccesscommandCMD11CMD12CMD18CMD12CRCDATACRCDATACRCDATACRCDATACRCDATACMD17CRCDATACMD17CRCDATACMD17CRCDATACMD17CRCDATACMD17CRCDATADATADATADATADATADATAAccessmode(forMMCmode)15MultiMediaCardCommand16CommandformatBitpositionWidth(bits)ValueDescription4710Startbit4611transmissionbit[45:40]6Xcommandindex[39:8]32Xargument[7:1]7XCRC7011endbit[47]---------[0]SerialDataCommandconsistsof48bits(6Bytes)17MMCmodecommandCommanddescriptionCMDindexCMD1CMD2CMD3CMD4CMD11CMD12CMD15CMD7CMD13CMD16CMD17CMD18CMD20CMD9CMD10CMD0ResetsallcardstoidlestateAsksallcardsinidlestatetosendtheiroperationconditionsregistercontentsintheresponseontheCMDline“”.AskallcardstosendtheirCIDnumbersontheCMDlineAssignsrelativeaddresstothecardProgramstheDSRofallcardsCommandtogglesacardbetweenthestand-byandtransferstatesorbetweentheprogramminganddisconnectstatus.Inbothcasesthecardisselectedbyitsownrelativeaddressandgetsdeselectedbyanyotheraddress.Addressedcardsendsitscard-specificdata(CSD)ontheCMDline.Addressedcardsendsitscardidentification(CID)onCMDline.Readsdatastreamfromthecard,startingatthegivenaddress,untilaSTOP_TRANSMISSIONfollows.Terminatesaread/writestream/multipleblockoperation.WhenCMD12isusedtoterminateareadtransactionthecardwillrespondwithR1.WhenitisusedtostopawritetransactionthecardwillrespondwithR1b.Addressedcardsendsitsstatusregister.Setsthecardtoinactivestateinordertoprotectthecardstackagainstcommunicationbreakdowns.Setsth