I have added a few new pictures to the xt/370 web site showing the stacked (and
non-stacked) versions of the MCM66128L20, as well as two other examples of IBM engineering
that employed stacked chips (AT motherboard and PC memory card) in the early 1980's.
There are 36 pairs on the AT board to get 512K and 18 pairs on the memory card to get
Obviously, these chips have different pinouts (at least select).
The url is:- www.xt370.net
click on the link to the left, 'Memory Technology'
The question a data sheet might answer is:- does one of the new MCM66128L20 parts replace
one of the old stacked pairs?
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Subject: Re: Someone in search of XT/370 software
To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org>
He's on the list. I have at least some of VM/PC, but when I tried to
email him to let him know, I got an autoresponse from a white-list
agent, which sent me to an unresponsive URL. It was sufficiently
irritating that I figured it wasn't worth pursuing further.
Seriously, folks, if you're going to ask for help, don't make it
impossible for people to give.
Bear's criticism is well-founded.
I believe I have corrected the problem; I did receive the e-mails and have responded
At any rate, I greatly appreciate the interest and am sorry for the inconvenience.