Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Elliott Lee <tenchi@netmagic.net>
Newsgroups: scea.yaroze.programming.sound
Subject: Re: Sound questions
Date: Mon, 13 Apr 1998 13:47:25 -0700
Organization: Cisco Systems
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Scott Cartier wrote:
> 
> Bear with me for a moment as my questions may seem trivial.
> 
> Is there any way to use the general MIDI instruments without loading
> them
> into the sound RAM?  They occupy 400k so that eats up almost all of the
> space.  If not, then what's the advantage of using the supplied general
> MIDI instruments over your own?
	[...]

There is a way to reduce that 400K.  Load the GM sample set from
the CD (VB) into something like 800A0000h and the header (VH) into
80090000h.  Do your SsVabTransfer and then blow away the contents
of the VB.  Once the sound data has been transfered to the SPU RAM,
you can overwrite it.  The VH header, however, must remain resident.

Space-saving suggestion:
========================
What you could theoretically do is pack all of your code, graphics,
sound effects, and whatnot into a compressed format and set up your
RAM into something like this:

	80090000-800BFFFF	main code
	800C0000-8013FFFF	compressed, packed data
	80140000-8015FFFF	General MIDI VH
	80160000-801EFFFF	free scratchpad

Have your code search the CD for the General MIDI header and load
it at 80140000h, and the instrument sample data at 80160000h.  Do
the VAB transfer, and then that scratchpad area is free to be
overwritten.  You can then unpack your graphics from the compressed
memeory area and individually transfer them up to the VRAM...

That should give you a lot more room to play with.

- e!
  tenchi@netmagic.net
  http://www.netmagic.net/~tenchi/yaroze/