Mikael Elharrar

Configure DMA with SPI master

Discussion created by Mikael Elharrar on Jul 18, 2017
Latest reply on Aug 1, 2017 by Hui_Ma

Hi ,

I don't succeed to configure correctly my SPI + DMA on kinetis 64.

The SPI should works as master.

I configured 2 DMA channels (Rx and Tx).

DMA Tx channel is triggered by an external GPIO.

Minor loop is 12 bytes and major loop 32, so the Rx buffer size is 32*12 bytes.


The trigger transfer to DMA Tx channel seems to work, but I dont get anything on the Rx buffer.

Two possibilities I think:

   - The DMA Tx channel is correctly triggered but don't send anything on the SPI Tx wire.

   - The DMA Rx channel of the SPI Rx channel is not correctly configured.


I attached here my code.


Note that I'm using the "fsl_edma" driver and not "fsl_dspi_edma" driver because this later does'nt manage the minor and major loop like I need.


Thank you for your help.



Original Attachment has been moved to: ads131.c.zip