s32k148 spi can transmit but receive 0

[xyj1230730]

Hi~

board:  s32k148 176LQFP

code: s32ds example project ---- lpspi_transfer_s32k148

power: miniusb 5v

problem: slave can receive but master receive data 0

loop function: 

          slaveDataSend = 140;
          LPSPI_DRV_SlaveTransfer(RECEIVE, &slaveDataSend, &slaveDataReceive, 1);
          LPSPI_DRV_MasterTransferBlocking(SEND, &masterDataSend, &masterDataReceive, 1, 10);

debug information: slave and master modelcan both enter the interrupt function to process receive and transmit data,slave device can receive data from master device,but master device recieve data from slave are 0

configuration: 

LPSPI0:MASTER

const lpspi_master_config_t Send_MasterConfig0 = {
  .bitsPerSec = 50000U,
  .whichPcs = LPSPI_PCS0,
  .pcsPolarity = LPSPI_ACTIVE_LOW,
  .isPcsContinuous = false,
  .bitcount = 8U,
  .lpspiSrcClk = 48000000U,
  .clkPhase = LPSPI_CLOCK_PHASE_1ST_EDGE,
  .clkPolarity = LPSPI_SCK_ACTIVE_HIGH,
  .lsbFirst = true,
  .transferType = LPSPI_USING_INTERRUPTS,
  .rxDMAChannel = 255,
  .txDMAChannel = 255,
  .callback = NULL,
  .callbackParam = NULL,
};

LPSPI1:SLAVE

lpspi_slave_config_t Receive_SlaveConfig0 = {
  .pcsPolarity = LPSPI_ACTIVE_LOW,
  .bitcount = 8U,
  .clkPhase = LPSPI_CLOCK_PHASE_1ST_EDGE,
  .whichPcs = LPSPI_PCS0,
  .clkPolarity = LPSPI_SCK_ACTIVE_HIGH,
  .lsbFirst = true,
  .transferType = LPSPI_USING_INTERRUPTS,
  .rxDMAChannel = 255,
  .txDMAChannel = 255,
  .callback = NULL,
  .callbackParam = NULL,
};

May I ask what is the cause of this phenomenon?

thanks !

[danielmartynek]

Hi,

Do you monitor PTE1 with a logic analyzer/oscilloscope?

Thanks,

Daniel

[xyj1230730]

Hi

Thanks for your attention,because there is no logic analyzer/oscilloscope,so I'm not sure about this,could I have another ways to found out the reason?

Thanks

xia

[danielmartynek]

Hi,

It would really help if you measured it, to see if the slave returns something.

Anyway, how do you know that the received data == 0, only by checking the SW receive buffer?

Do you see any LPSPI error flags? 

Regards,

Daniel

[xyj1230730]

Hi

There is no error flags,the data==0 showed in receive model ,and (uint32_t)base->RDR data is also 0 in the interrupt function. because there is no analyzer/oscilloscope,so I can't provide measure data. 

Can test The s32k148-176  lpspi in the same board over lpspi0 for master and lpspi1 for slave?

Thanks!

xia

[danielmartynek]

Hi,

Have you tried the lpspi_transfer_s32k148 SDK example first?

Does it work?

Regards,

Daniel