Path: utzoo!utgpu!attcan!uunet!seismo!sundc!pitstop!sun!amdcad!ames!pasteur!agate!ucbvax!STONY-BROOK.SCRC.SYMBOLICS.COM!jrd
From: jrd@STONY-BROOK.SCRC.SYMBOLICS.COM (John R. Dunning)
Newsgroups: comp.sys.atari.st
Subject: Register saving for BIOS traps?
Message-ID: <19880922163903.5.JRD@MOA.SCRC.Symbolics.COM>
Date: 22 Sep 88 16:39:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 11

I think I remember a discussion about this a while ago, but don't
remember the outcome.

I believe it's necessary to save (some) registers around BIOS and XBIOS
traps.  The question for today is: which ones?  Is there any rhyme or
reason to which registers get trashed inside the trap?

A related question; am I correct in assuming that GEMDOS traps don't
require register saving?

Thanks in advance for any info.