Ogg+RTEMS on GameBoy Advance was Re: RTEMS device driver and interrupt

[Mike Panetta]

On Fri, 2002-04-12 at 11:32, Joel Sherrill wrote:
> 
> 
> Mike Panetta wrote:
> > 
> > Thinking GBA are we?  An ogg player for the GBA might be pretty neat.
> > Esp if it had some sort of visualization like winamp or whatnot.
> 
> Busted.  So the big question now.. 
>   
>   Is this a feasible project from a HW perspective?
> 
> The GBA has 16 Mhz ARM, 32K+256K RAM, <= 256Mb flash, and as best
> I can tell 8 bit stereo.  I know the sound won't please an 
> audiophile but is this doable given the HW limitations.
> 

I think we would need to have your previous question answered first,
before we could make any educated guesses on that.  I myself do not know
much about the ogg format to guess :).  As for ram, I bet it would not
be too hard to add some external ram where the flash would normally be. 
You would just need some sort of burst counter and address demux in an
external CPLD I think.  The only thing I can think of that would prevent
it would be if the GBA disalowed writes to the ROM address space.  The
burst counter and demux would be needed to interface flash anyways if I
read the schematics right on the pages I looked at, so its not much
added effort.  I do know about the RAM space that the GBA cartrage has,
but it would only allow you to add an additional 64K of ram IIRC, which
would not be significant (or would it?  I guess we would need to know
buffer size requirements to figure that one out).

Mike
> --joel
> 
> > Mike
> > 
> > On Fri, 2002-04-12 at 06:03, Joel Sherrill wrote:
> > >
> > >
> > [...]
> > >
> > > I am generally trying to figure out how small an embedded system
> > > can be from a HW perspective and still do this.
> > >
> > > --joel
> 
> 
> -- 
> Joel Sherrill, Ph.D.             Director of Research & Development
> joel at OARcorp.com                 On-Line Applications Research
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