SPI example with 16 bit character width?

Markus Grunwald

Expert 2060 points

Hello,

I'm playing with the example from pspdrivers_01_20_00\packages\ti\pspiom\examples\evm6747\spi\edma\. I changed the configuration so that the DSP is in slave mode and character length is 16 bit. The example worked, but I got only rubbish as input...

Then a colleague found this:

Spi_edma.c :

Int Spi_localEdmaTransfer(Spi_Object      *instHandle,
                          Spi_DataParam   *dataParam)
{

....

        /* FIFO width is 8 bit                                                */
        paramSet.opt &= 0xFFFFF8FFu;

....

}

So we changed our setup to send 8 bit characers and we got sane data. Now I wonder how to change the example to use 16 bit characters.... I figured out that I might have to use

EDMA3_DRV_FifoWidth in combination with EDMA3_DRV_setSrcParams/EDMA3_DRV_setDestParams but didn't get much further... Is there some documentation for this? The "EDMA3 DRIVER DATASHEET" mentions a "EDMA3 Driver Help File" but neither google nor I were able to find it...

TIA

Markus

over 14 years ago

0 Sandeep Krishnaswamy over 14 years ago

TI__Expert 7290 points

Hi Markus,

Could you please replace existing code,

        if (FALSE == chanHandle->rxBufFlag)
        {
            paramSet.destBIdx = 0;
        }
        else
        {
            paramSet.destBIdx = 1;
        }

with

        if (FALSE == chanHandle->rxBufFlag)
        {
            paramSet.destBIdx = 0;
        }
        else
        {
            paramSet.destBIdx = acntFlag;
        }

in the function Spi_localEdmaTransfer() in the file spi_edma.c and rebuild the SPI driver.

Regards,

Sandeep K

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SPI example with 16 bit character width?