I'm trying to use SPI DMA with FIFO to read a ADC. The working procedure of my code is as below:
ADC give a interrupt to inform the data is ok to read, then we kick start the SPI DMA to read 16bits x 4 (4 half words), and store them into some mem locations. If I don't enable FIFO, all work well. When I tried to use FIFO as below:
But the data read back are wrong. I doubt I don't understand the usage of FIFO, so how should I set the FIFO in my situations?