DMA: 2 descriptors, one trigger

[TamirM]

Hi,

I'm trying to apply DMA on ADC.

I would like that the 'eoc' trigger would start 2 transfers: of channel 0, and channel 1.

my code:

DMA_SetSrcAddress(1, (void *)ADC_SAR_SAR_CHAN1_RESULT_PTR);
DMA_SetDstAddress(1, (void *)&currentB);
DMA_ValidateDescriptor(1);

DMA_Start((void *)ADC_SAR_SAR_CHAN0_RESULT_PTR, (void *)&currentA);

The problem is that only channel 0 is updating.

if i chain descriptor 0 to descriptor 1 then only channel 1 updates.

what is the correct configuration.

ADC with DMA and descriptors configuration attached

[Hari · Accepted solution]

Hi @TamirM 

You can simply connect both drqs to the ADC's EOC pin. That way, both the channels will get triggered simultaneously. I have created a project for the 5888LTI part. Please try this out and let me know if this is the requirement. 

Best regards, 
Hari

[TamirM]

I wanted to use 1 DMA with 2 descriptors, but this method seems to work as well.

Thanks