Article View: comp.sys.mac
Article #9448Re: MacIIci Video/Memory Question
From: Joel B Levin
Date: Wed, 13 Dec 1989 16:27
Date: Wed, 13 Dec 1989 16:27
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1356 bytes
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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Path: arc1-ca.pugleaf.net!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