Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!hp4nl!philapd!ssp11!dolf
From: dolf@idca.tds.PHILIPS.nl (Dolf Grunbauer)
Newsgroups: comp.sys.m68k
Subject: Re: 68040 not object code compatible?
Message-ID: <659@ssp11.idca.tds.philips.nl>
Date: 26 Feb 90 12:46:34 GMT
References: <300003@hpclkms.HP.COM>
Organization: Philips Information Systems, Apeldoorn, The Netherlands
Lines: 21

In article <300003@hpclkms.HP.COM> ken@hpclkms.HP.COM (Ken Sumrall) writes:
>I just got the 68040 User's Manual, and was perusing the appendix which
>discusses the various features of the different members of the 68000 family.
>In the table on page A-3, the CALLM instruction is shown to be implemented
>only on the 68020.  However, on page 1-1, the 68040 is claimed to be
>user object code compatible with previous members of the 68000 family.

In my MC68030 User's Manual (section 12.1.3, page 12-3):
	When used in a system originally designed for an MC68020 a
	difference a programmer must be aware of is that the MC68030
	does not support the CALLM and RTM instruction of the MC68020.
	If code is executed on the MC68030 using either the CALLM or
	RTM instructions, an unimplemented instruction exception is taken.

So the MC68040 is apparently more compatible with an MC68030 than with
an MC68020.
-- 
Dolf Grunbauer          Tel: +31 55 433233  Internet dolf@idca.tds.philips.nl
Philips Telecommunication and Data Systems  UUCP ....!mcvax!philapd!dolf
Dept. SSP, P.O. Box 245, 7300 AE Apeldoorn, The Netherlands         n   n   n
It's a pity my .signature is too small to show you my solution of  a + b = c