EDMA to DAC on E5

Go To Last Post
2 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hobby project time, I'm trying to DMA data from RAM to the DAC on an E5.

 

Everyone else who has done this seems to be using the EDMA in standard channel mode, rather than peripheral channel mode. If you need double buffering with that it used up all four EDMA channels, but at least it works.

 

In peripheral channel mode the EDMA copies data from RAM to the DAC's data register. It seems to work if you manually trigger it, but the problem is getting it to trigger from a timer. You have to set the EDMA trigger source to DACA in order to also set the destination address. In any case, there is no option to trigger from a timer or event. Problem is, it never triggers.

 

I set the DAC to use an event triggered by a timer. The events are being generated, I can run other stuff from them. I presume the DAC is triggering conversions from the events too, but it doesn't trigger the EDMA so the output is a constant value.

 

Has anyone made this work? How is it even supposed to work? Is it just broken?

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Any luck here? I have very similar problems if not the same, described here:

http://www.avrfreaks.net/forum/e...