dsp 28335 教程 12

《dsp 28335 教程 12》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、CommunicationsModule11TMS320C28x™MCUWorkshopCopyright©2009TexasInstruments.Allrightsreserved.TechnicalTrainingOrganizationTTOLearningObjectivesSerialPeripheralInterface(SPI)SerialCommunicationInterface(SCI)MultichannelBufferedSerialPort(McBSP)Inter-IntegratedCircuit(I2C)EnhancedControllerAre

2、aNetwork(eCAN)Note:Upto1SPImodule(A),3SCImodules(A/B/C),2McBSPmodules(A/B),1I2Cmodule(A),and2eCANmodules(A/B)areavailableontheF2833xdevices.Synchronousvs.AsynchronousSynchronousShortdistances(on-board)HighdatarateExplicitclockAsynchronouslongerdistancesLowerdatarate(1/8ofSPI)Impliedclock(cl

3、k/datamixed)EconomicalwithreasonableperformanceC28xU2PCBPortC28xPCBPortDestinationLearningObjectivesSerialPeripheralInterface(SPI)SerialCommunicationInterface(SCI)MultichannelBufferedSerialPort(McBSP)Inter-IntegratedCircuit(I2C)EnhancedControllerAreaNetwork(eCAN)SPIDataFlowSPIShiftRegisterSP

4、IDevice#1-MasterSPIDevice#2-SlaveSimultaneoustransmitsandreceiveSPIMasterprovidestheclocksignalshiftshiftclockSPIShiftRegisterSPIBlockDiagramSPIRXBUF.15-0SPIDAT.15-0SPICLKSPISOMISPISIMOLSPCLKbaudrateclockpolarityclockphaseC28x-SPIMasterModeShownSPITXBUF.15-0LSBMSBTXFIFO_0TXFIFO_15RXFIFO_0RXF

5、IFO_15SPIDataCharacterJustificationProgrammabledatalengthof1to16bitsTransmitteddataoflessthan16bitsmustbeleftjustifiedMSBtransmittedfirstReceiveddataoflessthan16bitsarerightjustifiedUsersoftwaremustmask-offunusedMSB’s11001001XXXXXXXXXXXXXXXX11001001SPIDAT-Processor#1SPIDAT-Processor#2SPIBaud

6、RateRegisterSpixRegs.SPIBRR15-76-0reservedSPIBITRATESPICLKsignal=LSPCLK(SPIBRR+1)LSPCLK4,SPIBRR=3to127,SPIBRR=0,1,or2Needtosetthisonlywheninmastermode!SelectSPIRegistersConfigurationControlSpixRegs.SPICCRReset,ClockPolarity,Loopback,CharacterLengthOperationControlSpixRegs.SPICTLOverrunInterr

7、uptEnable,ClockPhase,InterruptEnableMaster/SlaveTransmitenableStatusSpixRegs.SPISTRXOverrunFlag,InterruptFlag,TXBufferFullFlagFIFOTransmitSpixRegs.SPIFFTXFIFOReceiveSpixRegs.SPIFFRXFIFOEnable,FIFOResetFIFOOver-flowflag,Over-flowClearNumberofWordsin