Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!usc!brutus.cs.uiuc.edu!apple!kateley
From: kateley@Apple.COM (Jim Kateley)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Summary: PMMUs vs Mac IIs -- which ones don't work
Message-ID: <38518@apple.Apple.COM>
Date: 10 Feb 90 21:11:16 GMT
References: <3092@pur-phy>
Organization: Apple Computer, Metro Plaza, San Jose CA
Lines: 33

In article <3092@pur-phy> sho@maxwell.physics.purdue.edu.UUCP (Sho Kuwamoto) writes:
>You machine will be affected if you have Rev. A ROMs.  They moved
>to Rev. B ROMs sometime around February 1988.

Actually, there are two seperate repair extenstion programs for the Macintosh
II. 

The first, announced in Feburary of 1988, addresses a ROM glitch where
NuBus cards with more than 1MB of address space cannot be accessed.  This is
the "Rev A to Rev B" program.  Your dealer can see page 8.4.13 of their service
programs binder for details. 

The other, announced in August of 1989, is for the HMMU/PMMU socket situation
where the socket for the PMMU on some units does not have all the necessary
pins for a PMMU to function (although it does have enough pins for the HMMU).
Your dealer can see page 8.4.14 of their service programs binder for details.

In the first case, you would have a problem if you had a NuBus card that
required more than 1MB of address space.  In the second case, your MacII
would not work if you installed a PMMU.

Both situations require a main logic board swap, which is at no cost to you.
>
>-Sho
>--
>sho@physics.purdue.edu  <<-- the public should know.


-- 
Jim Kateley          UUCP: {sun, voder, nsc, mtxinu, dual}!apple!kateley
S,P,HnS!             DOMAIN: kateley@apple.COM  Applelink: kateley1
Disclaimer:   What I say, think, or smell does not reflect any policy or
	      stray thought by Apple Computer, Inc.