Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!oliveb!apple!tecot
From: tecot@Apple.COM (Ed Tecot)
Newsgroups: comp.sys.mac
Subject: Re: '030 daughterboard possible?
Message-ID: <28063@apple.Apple.COM>
Date: 29 Mar 89 23:37:21 GMT
References: <933@fornax.UUCP>
Distribution: na
Organization: Apple Computer Inc, Cupertino, CA
Lines: 21

In article <933@fornax.UUCP> mcdonald@fornax.UUCP (Ken Mcdonald) writes:
>One of the biggest disappointments to me in terms of Apple's upgrade
>behaviour concerning the Mac II was the implicit soft shoe routine they
>pulled by putting a PMMU socket on the Mac II board, and then never releasing
>a Mac II with a PMMU, but instead going to the '030 WITHOUT PROVIDING A SIMPLE
>DAUGHTERBOARD EXPANSION to retrofit an '030 to the Mac II.  I can't see any
>technical reason it can't be done, it would give you essentially a IIx (call
>it a IIx/2?) at a far lower price than a motherboard swap, and it wouldn't cost
>anymore than buying a PMMU for the II.  The advantages are that you sidestep any
>weird campatability problems arising from the differences in the PMMU's, and
>you don't have the penalty of an extra wait state.  Of course, if there are
>technical reasons why a daughterboard like this can't be produced (which is my
>question, natch--is this feasible), then flame on.  Otherwise, flame Apple.

Actually the early IIx prototypes were daughterboards.  They proved to be
unreliable and could not be FCC or (the european equivalent) approved, making
them difficult to impossible to sell.  Instead, the hardware design team
chose to recommend 68851s to current Mac II owners, for greater reliability
at a lower price.

						_emt