TMS570LC4357: want the sample code for the SPI communication using DMA.

Hello,

We don't have example code for chaining. Chain[5:0] field of the Channel Control Register is used to program the chaining.

Best regards,
Miro

Hi,

For SPI-DMA currently i am using the dma req lines 0 and 1 for the reception and transmission of SPI1 respectively, where the req lines is assigned to channel 0 and 1.

with this it is working properly.

Now when i want to use the dma req lines 4 and 5 as reception and transmission for SPI1 as well, i am not getting any response in the RXDATA which is receive buffer in SRAM.

I am assigning this req lines with the channel number 4 and 5 respectively.

I am using following lines of code where g_dmaCTRLPKT2 packet configured for reception and g_dmaCTRLPKT1 as transmission

/* - setting dma control packets */
dmaSetCtrlPacket(DMA_CH4,g_dmaCTRLPKT2);

dmaSetCtrlPacket(DMA_CH5,g_dmaCTRLPKT1);

/* - setting the dma channel to trigger on h/w request */

dmaSetChEnable(DMA_CH4, DMA_HW);

dmaSetChEnable(DMA_CH5, DMA_HW);

/*5-transmit,4-receive*/

dmaReqAssign(DMA_CH4, DMA_REQ4);
dmaReqAssign(DMA_CH5, DMA_REQ5);

dmaEnable();

dmaEnableInterrupt(DMA_CH4, BTC, DMA_INTA);

spiREG1->INT0 |= 0x00010000;

while(dmaGetInterruptStatus(DMA_CH4, BTC) != TRUE);

dmaDisableInterrupt(DMA_CH4, BTC);

Same thing is happening when i am using req lines 8 and 9.only working with the req lines 0 and 1. why is it so?

Do I need to consider any other register, if for a particular req line has more than single module is assigned?(TRM 6.17.3)

Can you please help me with this?

Regards,

Shivam Kakad.

Hello,

Here I found example for chaining: 

For using DMA with SPI1 in compatible mode you have to use DMAREQ[0] and DMAREQ[1]

Best regards,
Miro