MCP2515

©2005MicrochipTechnologyInc.PreliminaryDS21801D-page1MCP2515Features•ImplementsCANV2.0Bat1Mb/s:-0–8bytelengthinthedatafield-Standardandextendeddataandremoteframes�Receivebuffers,masksandfilters:-Tworeceivebufferswithprioritizedmessagestorage-Six29-bitfilters-Two29-bitmasks�Databytefilteringonthefirsttwodatabytes(appliestostandarddataframes)�Threetransmitbufferswithprioritizatonandabortfeatures�High-speedSPI™Interface(10MHz):-SPImodes0,0and1,1�One-shotmodeensuresmessagetransmissionisattemptedonlyonetime�Clockoutpinwithprogrammableprescaler:-Canbeusedasaclocksourceforotherdevice(s)�Start-of-Frame(SOF)signalisavailableformonitoringtheSOFsignal:-Canbeusedfortime-slot-basedprotocolsand/orbusdiagnosticstodetectearlybusdegredation�Interruptoutputpinwithselectableenables�BufferFulloutputpinsconfigurableas:-Interruptoutputforeachreceivebuffer-Generalpurposeoutput�Request-to-Send(RTS)inputpinsindividuallyconfigurableas:-Controlpinstorequesttransmissionforeachtransmitbuffer-Generalpurposeinputs�Low-powerCMOStechnology:-Operatesfrom2.7V–5.5V-5mAactivecurrent(typical)-1µAstandbycurrent(typical)(Sleepmode)�Temperaturerangessupported:-Industrial(I):-40°Cto+85°C-Extended(E):-40°Cto+125°CDescriptionMicrochipTechnology’sMCP2515isastand-aloneControllerAreaNetwork(CAN)controllerthatimple-mentstheCANspecification,version2.0B.Itiscapableoftransmittingandreceivingbothstandardandextendeddataandremoteframes.TheMCP2515hastwoacceptancemasksandsixacceptancefiltersthatareusedtofilteroutunwantedmessages,therebyreducingthehostMCUsoverhead.TheMCP2515interfaceswithmicrocontrollers(MCUs)viaanindustrystandardSerialPeripheralInterface(SPI).PackageTypesTXCANRXCANVDDRESETCSSOMCP2515123418171615SISCKINTRX0BF14131211RX1BF10OSC2OSC1CLKOUT/SOFTX2RTS5678Vss9TX0RTSTX1RTSMCP2515TXCANRXCANTX0RTSOSC1CLKOUT/SOFOSC2CSVDDRESETSOSCKINTSIRX0BFRX1BFVSSTX1RTSTX2RTSNCNC131212345678920191817161514111018-LeadPDIP/SOIC20-LEADTSSOPStand-AloneCANControllerWithSPI™InterfaceMCP2515DS21801D-page2Preliminary©2005MicrochipTechnologyInc.NOTES:©2005MicrochipTechnologyInc.PreliminaryDS21801D-page3MCP25151.0DEVICEOVERVIEWTheMCP2515isastand-aloneCANcontrollerdevelopedtosimplifyapplicationsthatrequireinterfacingwithaCANbus.AsimpleblockdiagramoftheMCP2515isshowninFigure1-1.Thedeviceconsistsofthreemainblocks:1.TheCANmodule,whichincludestheCANprotocolengine,masks,filters,transmitandreceivebuffers.2.Thecontrollogicandregistersthatareusedtoconfigurethedeviceanditsoperation.3.TheSPIprotocolblock.AnexamplesystemimplementationusingthedeviceisshowninFigure1-2.1.1CANModuleTheCANmodulehandlesallfunctionsforreceivingandtransmittingmessagesontheCANbus.Messagesaretransmittedbyfirstloadingtheappropriatemessagebufferandcontrolregisters.TransmissionisinitiatedbyusingcontrolregisterbitsviatheSPIinterfaceorbyusingthetransmitenablepins.Statusanderrorscanbecheckedbyreadingtheappropriateregisters.AnymessagedetectedontheCANbusischeckedforerrorsandthenmatchedagainsttheuser-definedfilterstoseeifitshouldbemovedintooneofthetworeceivebuffers.1.2ControlLogicThecontrollogicblockcontrolsthesetupandoperationoftheMCP2515byinterfacingtotheotherblocksinordertopassinformationandcontrol.Interruptpinsareprovidedtoallowgreatersystemflexibility.Thereisonemulti-purposeinterruptpin(aswellasspecificinterruptpins)foreachofthereceiveregistersthatcanbeusedtoindicateavalidmessagehasbeenreceivedandloadedintooneofthereceivebuffers.Useofthespecificinterruptpinsisoptional.Thegeneralpurposeinterruptpin,aswellasstatusregisters(accessedviatheSPIinterface),canalsobeusedtodeterminewhenavalidmessagehasbeenreceived.Additionally,therearethreepinsavailabletoinitiateimmediatetransmissionofamessagethathasbeenloadedintooneofthethreetransmitregisters.Useofthesepinsisoptional,asinitiatingmessagetransmissionscanalsobeaccomplishedbyutilizingcontrolregisters,accessedviatheSPIinterface.1.3SPIProtocolBlockTheMCUinterfacestothedeviceviatheSPIinterface.Writingto,andreadingfrom,allregistersisaccomplishedusingstandardSPIreadandwritecommands,inadditiontospecializedSPIcommands.FIGURE1-1:BLOCKDIAGRAMSPI™InterfaceLogicSPIBusINTCSSCKSISOCANProtocolEngineRXCANTXCANControlLogicRX0BFRX1BFTX0RTSTX1RTSTX2RTSTXandRXBuffersMasksandFiltersCANModuleRESETTimingGenerationOSC1OSC2CLKOUTControlandInterruptRegistersMCP2515DS21801D-page4Preliminary©2005MicrochipTechnologyInc.FIGURE1-2:EXAMPLESYSTEMIMPLEMENTATIONTABLE1-1:PINOUTDESCRIPTIONNamePDIP/SOICPin#TSSOPPin#I/O/PTypeDescriptionAlternatePinFunctionTXCAN11OTransmitoutputpintoCANbus—RXCAN22IReceiveinputpinfromCANbus—CLKOUT33OClockoutputpinwithprogrammableprescalerStart-of-FramesignalTX0RTS44ITransmitbufferTXB0request-to-send.100kΩinternalpull-uptoVDDGeneralpurposedigitalinput.100kΩinternalpull-uptoVDDTX1RTS55ITransmitbufferTXB1request-to-send.100kΩinternalpull-uptoVDDGeneralpurposedigitalinput.100kΩinternalpull-uptoVDDTX2RTS67ITransmitbufferTXB2request-to-send.100kΩinternalpull-uptoVDDGeneralpurposedigitalinput.100kΩinternalpull-uptoVDDOSC278OOscillatoroutput—OSC189IOscillatorinputExternalclockinputVSS910PGroundrefer