Is something using DMA channel 0?

Craig McGeachie slapdau at
Thu Nov 7 03:44:49 EST 2013

On 11/07/2013 09:03 PM, Richard Hirst wrote:
> Servoblaster uses DMA channel 0 from user space too, by directly
> accessing registers through /dev/mem.  That is quite widely used and I
> haven't heard of any issues with it.  That code to turn the Pi in to an
> FM radio transmitter did it too.  I'm not trying to suggest it is a good
> approach, but it seems to work in many cases.

That being the case, then I really have no idea.  I don't own any 
servos, otherwise I might have been tempted to see if I could find a way 
to cause Servoblaster to break by generating screen buffer activity. 
Compare headless vs. console vs. GUI.

Oh well.  Best of luck Philip.


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