Article View: comp.sys.mac
Article #18133Getting 1 Meg SIM boards to work in your Mac
From: Jeff Meyer
Date: Fri, 14 Aug 1987 22:51
Date: Fri, 14 Aug 1987 22:51
33 lines
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2649 bytes
The other day, I noticed that one of our hardware engineers had got some
sample 1-Megabyte SIM RAM cards from a vendor for trial. On a whim (OK,
some self-interest involved), I decided to try upgrading a Mac+ with these
surface-mount cards -- they looked quite similar, and the sockets were the
same (their access time was 120ns, which is certainly fast enough for a Mac+
or even a Mac II). Well, no combination of two Mac+ 256K cards / 2 1 MB
cards (for a total of 2.5 MB) seemed to work -- Funny screen patterns, weird
backup screens), so I had little hope of getting it to work.
However, when I stuck four of the 1MB boards in.... Ding! Everything works
like a charm -- EXCEPT the Finder reports it has only 2048K (read: 2 MB)
available. Well, shoot.
A friend tells me that something needs to be jumpered on the Mac+ board so
that the other 2M can be accessed, and he frowned on the possiblity of a
2.5MB combination. Two questions for you hardware people, or people who
have installed Dove upgrades WITH the 1 Megabyte cards (eight or nine chips
per card): Is 2.5 MB an impossibility? And what jumpered operations need to
be made to get a Mac+ to recognize that other 2MB? (This is the one I REALLY
want to get an answer to).
"One of the problems I've always had with propaganda
pamphlets is that they're real boring to look at.
They're just badly designed. People from the left
often are very well-intended, but they never had
time to take basic design classes, you know?"
-- Art Spiegelman
Moriarty, aka Jeff Meyer
INTERNET: moriarty@tc.fluke.COM
Manual UUCP: {uw-beaver, sun, allegra, hplsla, lbl-csam}!fluke!moriarty
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!uunet!husc6!mit-eddie!uw-beaver!fluke!moriarty From: moriarty@tc.fluke.COM (Jeff Meyer) Newsgroups: comp.sys.mac Subject: Getting 1 Meg SIM boards to work in your Mac Message-ID: <1492@sputnik.COM> Date: Fri, 14-Aug-87 18:51:52 EDT Article-I.D.: sputnik.1492 Posted: Fri Aug 14 18:51:52 1987 Date-Received: Sun, 16-Aug-87 05:22:37 EDT Sender: news@tc.fluke.COM Reply-To: moriarty@tc.fluke.COM (Jeff Meyer) Distribution: world Organization: John Fluke Mfg. Co., Inc., Everett, WA Lines: 33 Keywords: hardware memory SIM Summary: Do-it-yourself 4MB upgrades