DMA Transfer via SPI/SCI ports on F2806x devices

Terry,

SCI/SPI ports are not connected to DMA and hence does not support DMA transfers in F2806x devices.

Thanks and regards,
Vamsi

You can use the McBSP in SPI mode for SPI protocol transfer with the DMA though.

Kris

Does that mean we can not access DMA placed data on SARAM and use it for SCI transfer ?

Adnan

Adnan,

The DMA does not have access to the SCI or SPI ports on the F2806x.  So, you cannot have the DMA do transfers to/from these peripherals.

As Kris pointed out, the DMA has access to the McBSP.  So, you can put the McBSP in SPI mode and use the DMA to transfer data to/from it.

Regards,

David

Hi David,

Thanks for useful reply. To make sure of it, DMA does not access to SCI ports. OK. But SARAM area is software accessible isn't it? So, DMA placed data could be read and sent through SCI. Is that right?

This might help to gain simplicity and speed, getting the ADC data without CPU intervention, but fetching data and porting to SCI needs CPU data. Half of the data transfer load would be automatized. Could this be done?

Regards,
Adnan Kurt

Adnan,

Yes, you could have the DMA buffer data from the ADC. The buffer(s) would be in DMA accessible L5 - L8 SARAM. You could then have the CPU transfer the buffered data to the SCI for transmission. You could use the 4-level deep FIFO on the SCI to reduce the amount of interrupts the CPU has to take (e.g., transfer 4 values at a time into the FIFO).

Regards,
David

David, thanks for fast and exact answer.

Regards,