Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!wuarchive!mailrus!bbn!bbn.com!levin
From: levin@bbn.com (Joel B Levin)
Newsgroups: comp.sys.mac
Subject: Re: MacIIci Video/Memory Question
Message-ID: <49622@bbn.COM>
Date: 13 Dec 89 16:27:42 GMT
References: <483@ucl-cs.UUCP>
Sender: news@bbn.COM
Reply-To: levin@BBN.COM (Joel B Levin)
Organization: BBN Communications Corporation
Lines: 19

In article <483@ucl-cs.UUCP> J.Pearce@ucl-cs.UUCP writes:
|As I have been lead to understand the built-in video interface
|on the MacIIci uses bank A memory, but the Memory Decode Unit
|allows you to use non-contiguous memory. So is it possible to
|move half the memory in a 4M system to bank B, to reduce the
|performance degradation due to video lock-out?

Unfortunately, this would leave you with every other WORD (two bytes),
which is a little more noncontiguous than the engineers had in mind :-).

You need to set up SIMMs four-at-a-time because each SIMM contains
memory for eight bits of the thirty-two bit memory width for the
entire 4MB (or 1MB for 256KB SIMMs).

	/JBL
=
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