Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!van-bc!johna
From: johna@van-bc.UUCP (John Altstadt)
Newsgroups: comp.sys.atari.st
Subject: Re: Aerco 4 Meg ram upgrade boards
Message-ID: <144@van-bc.UUCP>
Date: 5 Jan 90 15:40:00 GMT
References: <131@van-bc.UUCP> <1990Jan3.220950.470@mentor.com>
Reply-To: johna@van-bc.UUCP (John Altstadt)
Organization: Wimsey Associates
Lines: 55

In article <1990Jan3.220950.470@mentor.com> dclemans@mentor.com (Dave Clemans @ APD x1292) writes:
+>From article <131@van-bc.UUCP>, by johna@van-bc.UUCP (John Altstadt):
(that's me)
+>> 
+>> Does anybody have any information on how to add 1 Meg chips to the
+>> Aerco "easieST" solderless ram upgrade for a 520?  The literature
+>> that came with the board claimed that the board would hold up to
+>> 4 Meg, but neglected to state how the extra ram should be added to
+>> the sockets provided.
+>
+>While the Aerco board can be upgraded to 4mb, it is NOT just a simple
+>matter of swapping chips (at least for the early boards that this
+>message talks about).  There are a number of traces that have to be
+>cut, jumpers that have to be added, resistors that have to be swapped,
+>etc.  The upgrade instructions were on the order of 10-20 pages.
+>
+>Note that the above doesn't apply for a 2.5 meg system; those were
+>just chip swaps.

Almost that simple.

>
+>To go to four megabytes, you have to cut traces/add jumpers to allow
+>one of the memory banks to take 1mb chips (256kb chips and 1mb chips
+>are not pin compatible; the Aerco board was shipped with one bank
+>set up for 256kb chips, and the other bank set up for 1mb chips;  to
+>goto 4mb you have to rewire the bank that was set up for 256kb chips).
>
+>dgc

Ooops, I should have been just a little more specific... I was having
problems upgrading to 2.5 meg.  A little local help here let me know
that upgrading to 2.5 meg requires pulling out the existing chips.  I
was under the impression that the 2.5 megs were all on the upgrade, not
split between the upgrade and the main board.

The package I bought contained the board (with 1/2 meg installed), a floppy
with two ram test programs, a multi-page photocopy showing how the board
was to be installed, and a 2.5 foot length of dental floss (to tie the
board in place!!!).  It did not contain any documentation on upgrading
to 2.5 meg, any documentation on upgrading to 4 meg, or a lifetime
subscription to PC Magazine.

Since I now have 2.5 meg running, could anybody send me info on how to
go all the way (or do I have to figure out which traces have to be cut
and which jumpers have to be soldered in myself?).

Last question:  does Aerco still exist as a corporate presence?

John

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