Re: Recode to Play MP3?

["Jeff Blakeney" <jeff.blakeney@a2central.com.remove-1v5-this>]

  To: Michael J. Mahon
On Fri, 25 May 2007 12:38:41 -0700, Michael J. Mahon wrote:

> It has to be moved from RAM to sound RAM, no exceptions.
> 
> And the move to sound RAM is fraught with uncertainties, since
> the GLU chip must share access to the sound RAM with the DOC chip.
> 
> I expect that with appropriate DOC initialization a much more
> favorable move-to-sound-RAM bandwidth is achievable, but I'll
> leave that experiment to someone more interested in the IIgs.

I'm not sure how it works now but I do remember one of the tool calls
allowed you to just give it a pointer (or possibly a handle) to an audio
sample in main RAM and it would take care of moving chunks of it into
DOC RAM and playing it and your program could go back to whatever it
wanted to do.  I believe an interrupt was generated or a message is sent
back to your main event loop when the sound finished playing

I don't have my references handy at present but I just found my copy of
_Inside The Apple IIGS_ by Gary Bond sitting here in a pile by my PC and
it says that to play a sample, it must be placed in the DOC RAM using
the registers of the GLU or by simply using the FFStartSound tool call.

> It would still be nice to speed up the CFFA.  ;-)

Faster mass storage is always a good thing.  :-)
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