>This afternoon, I was browsing my CodeWarrior Academic Pro 11 CD-ROM
>(yes, it's oooold but I got it for just $30) and came across the ROM
>maps under the MPW folder.  I guess these have the offset of ROM
>routine entries?

Yep. That's an *exteremly* handy set of files!

>Anyhow, I've managed to Build ROM.Maps, hoping the resulting output
>would be something more useful than the input files, but they look
>pretty much the same to me.  I mean, I have no idea how to interpret
>the files.
>
>How do I make use of them?

Ok, have a look at the .lst file. You'll see something like:

SETOSDEFAULT	Main		$75,$1430 	 E

as a ROM entry. The stuff you care about is the name (SETOSDEFAULT) and the
second hex value ($1430). That gives you the name of the routine and the
offset from the TOP of ROMs.

So what you do is drop into MacsBug and have a look at that offset from the
top of ROM with the disassembler and you're ready to start digging.

>(it'd be even cooler to get some clues on how to implement audio
>driver using the Singer codec and PSC).

Well, I've found that the in-ROM drivers are a little stripped down. However,
what is usually *extremely* informative is the device probe and init routines.
This gives you insight into how things are initialized properly and it helps
in finding out what "hidden" registers mean.

_______________________________________________________________________
 Michael Zucca - mrz5149@acm.org - http://www.rit.edu/~mrz5149/
 "I will choose a path that's clear. I will choose Freewill. "
  --Rush, Freewill
_______________________________________________________________________