Path: utzoo!attcan!uunet!cs.utexas.edu!sun-barr!apple!apple.com!shebanow
From: shebanow@apple.com (Andrew Shebanow)
Newsgroups: comp.sys.mac.programmer
Subject: Re: System 7.0 & 32 Bit Mode
Message-ID: <2033@internal.Apple.COM>
Date: 23 May 89 19:33:02 GMT
Sender: usenet@Apple.COM
Organization: Apple Computer, Inc.
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Just to set the record straight on the 32 Bit Mode discussions: although 
large parts of the ROMs are 32 Bit Clean, and can run in 32 bit mode, 
there are several crucial areas which are not. Most important of these is 
the Memory Manager, which initializes the System Heap at boot time, BEFORE 
any system patches can be installed (as Dave Berry pointed out). It would 
be very difficult (and very slow) to change heap formats at system patch 
time, and it would require patching out the entire Memory Manager and 
several other pieces of the toolbox, using up large amounts of precious 
physical RAM space.

Although I could expound on this stuff forever, I'll summarize:  under 
System 7.0, existing Mac II/IIx class machines will continue to run in 24 
Bit Mode. Eventually, Apple will release new ROMS (for new and/or existing 
machines) that will support 32 Bit Mode. System 7.0 WILL be able to run 
with these ROMs (trust me :-)).

I hope that this will end the confusion. I guess Tim wins this round :-).

Andrew Shebanow
Mr. Clean, MacDTS
- All Opinions Are Mine, and Mine Alone -