Path: utzoo!attcan!uunet!cs.utexas.edu!samsung!sdd.hp.com!uakari.primate.wisc.edu!aplcen!haven!mimsy!mojo!stripes
From: stripes@eng.umd.edu (Joshua Osborne)
Newsgroups: comp.sys.atari.st.tech
Subject: Re: floppies as swap space
Message-ID: <1990Aug2.191716.13909@eng.umd.edu>
Date: 2 Aug 90 19:17:16 GMT
References: <1700@troll.tubopal.UUCP>
Sender: news@eng.umd.edu (The News System)
Organization: College of Engineering, Maryversity of Uniland, College Park
Lines: 22

In article <1700@troll.tubopal.UUCP> ripley@tubopal.UUCP (Hans-Ch. Eckert) writes:
>[Another message I wanted to mail but it bounced... :-( ]
>
>[Q: How to use diskspace as additional memory?]
>How do you want to handle page faults (or similar)? The 68000 has a bug
>there and cannot continue exactly at the point the missing data got it!

I wouldn't call it a bug.  I doubt the 68000 ever had "support VM" in it's
design spec, and MC never tryed to fool anyone into thinking it did support
VM.  ('tho a great many little Unix boxes used the 68000 with swaping, not
paging, and they used the XOR insn to hit the lowest point on the stack that
a function would use, as part of some kludge that the ST can't do anyway
because it's "MMU" really doesn't do any V->P mapping).

At worst it's a design oversite in the 68000.  The 68010 was really the
first in the 68K line that was designed to support VM.
-- 
           stripes@eng.umd.edu          "Security for Unix is like
      Josh_Osborne@Real_World,The          Mutitasking for MS-DOS"
      "The dyslexic porgramer"                  - Kevin Lockwood
"Don't try to change C into some nice, safe, portable programming language
 with all sharp edges removed, pick another language."  - John Limpert