C6747 SPI PSP and Chip Select operation

Fyi, below is a wiki article that explains the SPI features like CSHOLD and delays a bit more...

http://wiki.davincidsp.com/index.php/Using_SPI_Chip_Select_Pin_on_C674x/OMAP-L1x

Thank you for the responses.  I checked the versions of drivers.  I am using PSP 01.20.00 and EDMA 01.06.00.01.  I checked the updates and didn't see a PSP version 01.30.00 - just 01.30.05 which is not a GA release.  I also checked the release notes in the PSP and didn't any mention of the problem I am seeing as a know issue or something that was fixed.  I can try and I upgrade but I want to confirm that will fix my issue before doing so.  I have to modify the EDMA and parts of the PSP files because the builds were too big for our application.  I would have to do the same for any new PSP release so don't want to do this unless I have to.

So Madhvapathi, can you send me all the settings you had for your SPI PSP parameters so I can compare.  Here is what I have for my settings:

int_fast8_t initialize_spi1_driver()
{
  GIO_Attrs gioAttrs = GIO_ATTRS;
  Spi_ChanParams chanParams;
  Int gio_create_status;
  int_fast8_t result_code; /* return 0 for successful driver initialization. */

  chanParams.hEdma = hEdma; /* SPI driver needs handle to edma for DMA mode. */

  /* create SPI channel for transmission */
  spi1_handle = GIO_create("/Spi1", IOM_INOUT, &gio_create_status, 
                         &chanParams, &gioAttrs);
  if(NULL == spi1_handle) {
    result_code = SP1_DRIVER_CREATE_FAIL;
  } else {
    result_code = SPI1_DRIVER_CREATE_SUCCESS;
  }

  spi1_dataparams.bufLen       = 0;
  spi1_dataparams.inBuffer     = (Uint8 *)&spi1_read_buffer[0];
  spi1_dataparams.outBuffer    = (Uint8 *)&spi1_write_buffer[0];
  /* use the following flag to indicate that SPI CS pin is held active between
     successive data word transactions. */
  spi1_dataparams.flags        = 0; //Spi_CSHOLD;
  spi1_dataparams.chipSelect   = 0x01;
  spi1_dataparams.dataFormat   = Spi_DataFormat_0;
  hSpi1_dataparams = &spi1_dataparams;

  return(result_code);
}

...

void spi1_user_init()
{
  spi1_params = Spi_PARAMS;

  spi1_params.hwiNumber = 8;
  spi1_params.opMode = Spi_OpMode_DMAINTERRUPT;

  /* this setting is a little bit deceiving.  The output clock cannot
     be set to any integer value.  It is translated into a prescale value
     for the SPI memory-mapped registers.  The SPI clock will run at
     SYSCLK2 / prescale value.  It seems like the PSP code will choose
     a prescale value that will produce a clock frequency nearest to that
     set by this field. */
  spi1_params.outputClkFreq     = 1000000; /* 1 MHz */
  spi1_params.loopbackEnabled   = FALSE;
  spi1_params.edmaHandle        = NULL;
  spi1_params.spiHWCfgData.waitDelay = TRUE;

  spi1_params.spiHWCfgData.pinOpModes = Spi_PinOpMode_SPISCS_4PIN;
  spi1_params.spiHWCfgData.intrLevel     = TRUE; /* map ints to INT1 */
  spi1_params.spiHWCfgData.csDefault = 1;

    spi1_params.spiHWCfgData.configDatafmt[0].wDelay       = 63;
  spi1_params.spiHWCfgData.configDatafmt[0].charLength   = 8;
  spi1_params.spiHWCfgData.configDatafmt[0].clkHigh      = TRUE; 
  spi1_params.spiHWCfgData.configDatafmt[0].lsbFirst     = FALSE;
  spi1_params.spiHWCfgData.configDatafmt[0].oddParity    = FALSE;
  spi1_params.spiHWCfgData.configDatafmt[0].parityEnable = FALSE;
  spi1_params.spiHWCfgData.configDatafmt[0].phaseIn      = FALSE;
  spi1_params.spiHWCfgData.configDatafmt[0].waitEnable   = FALSE;

  Spi_init(SPI_DEVICE1);
}

Another somewhat related question.  Why is the SPI clock frequency a module wide parameter, (e.g. a main field in the Spi_Params structure.) ?  The clock can be different for each of the data formats so it makes more sense to have this as a field in the Spi_ConfigDataFmt so a different clock can be preassigned for each data format that will be used.

thanks,

Mike

Mike said:

Thank you for the responses.  I checked the versions of drivers.  I am using PSP 01.20.00 and EDMA 01.06.00.01.  I checked the updates and didn't see a PSP version 01.30.00 - just 01.30.05 which is not a GA release. 

Our software download site changed to a new address/server a few months ago.  I imagine you're looking at the "legacy" releases.  Start at this page.  For C6747 PSP you'll then want to click on "BIOS Platform Support Packages" and then you'll see PSP 1.30.00.

The release notes also state:

"The GPIO Chip Select feature implementation of SPI driver has undergone

changes. This is to include provision for using more than on GPIO as Chip selecte.

The instance parameters and the I/O request (submit time) parameters have

undergone changes. Please refer to the SPI section of User guide for more

details."

I recommend getting on that most recent driver release so that you all the latest features and bug fixes.

I found my problem.  Another part of the code was setting the flags field (e.g. CSHOLD) back to 1 after it was initialized to 0.  So now I can see the CS feature operating properly.  And this is on PSP version 01.20 and EDMA 01.06.01.  I'll try and upgrade to the newer versions soon but it is a lot of work to make the same changes for each new PSP release so I need be prudent about this.  Do any of you know if the newest releases of PSP and EDMA reduced the memory usage from earlier versions?

Mike