Audio and mpc5200 bestcomm tasks

2009-05-21 Thread Jon Smirl
ALSA really wants to dynamically know the address of the current DMA
location while transfers are active. This is an important piece of
implementing pause/resume. Pause doesn't work too well if there is 2s
of music already queued. The work around is to know the sample rate
and use the jiffy count to estimate how far into the buffer DMA has
progressed. But that's not as accurate as just asking the DMA
hardware.

I poked around in the SRAM data and couldn't find the address. Is it
there or can the Bestcomm tasks be modified to leave it somewhere
visible?

-- 
Jon Smirl
jonsm...@gmail.com
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Re: Audio and mpc5200 bestcomm tasks

2009-05-21 Thread Grant Likely
On Thu, May 21, 2009 at 12:52 PM, Jon Smirl jonsm...@gmail.com wrote:
 ALSA really wants to dynamically know the address of the current DMA
 location while transfers are active. This is an important piece of
 implementing pause/resume. Pause doesn't work too well if there is 2s
 of music already queued. The work around is to know the sample rate
 and use the jiffy count to estimate how far into the buffer DMA has
 progressed. But that's not as accurate as just asking the DMA
 hardware.

 I poked around in the SRAM data and couldn't find the address. Is it
 there or can the Bestcomm tasks be modified to leave it somewhere
 visible?

It may be possible, but I haven't made any attempts at writing
bestcomm task code.  I've got no idea how difficult it would be.

g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
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