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From: ron minnich <>
To: The Eunuchs Hysterical Society <>
Subject: [TUHS] Burroughs funded $30,000 for a port to E-mode stack machine in 1983!
Date: Sun, 15 Jan 2023 11:09:59 -0800	[thread overview]
Message-ID: <> (raw)

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I just stumbled across an old letter, from a VP of Burroughs to me and
Steve Bartels, authorizing $30,000 for a port of Unix to the E-mode stack
machine. I had forgotten getting it.

Burroughs was famed for its stack machines. E-mode was a kind of last gasp
attempt to save the stack architecture, which failed as far as I know, see
this table:

I worked as a hardware engineer on the A15. I also had been a Unix user for
7 years at that point and kept pointing out how awful the Burroughs CANDE
time-sharing system was, and how much better Unix was. At some point I
guess they asked me to put up or shut up. I got that money, and left
Burroughs a week later for grad school.

Funny note: A15 was Motorola ECL (MECL), and ran at 16 Mhz., considered
fast at that time.  We used a technique called "stored logic" which was,
believe it or not, using MECL RAM to map logic inputs to outputs, i.e.
implement combinational logic with SRAM. Kind of nuts, but it worked at the
time. We also used a precursor of JTAG to scan it in. Those of you who know
JTAG have some idea of how fun this had to be.

One side effect of working with MECL is you realized just how well designed
the TI 7400 SSI/MSI parts were ... MECL always just felt like an awkward
family to design with.

Another funny story, pointing to what was about to happen to Burroughs. We
had an app that ran for hours on the stack machine. We quick ported it to a
VAX, started it up, and headed out to lunch -- "this will take a while,
let's go eat." We got to the front door and: "Oh, wait, let me hop back
into the office,I  forgot my jacket". And, noticed, the program was done in
... about 3 minutes. Not 8 hours.

That's when we knew it was game over for Burroughs.

If a picture of this letter would be useful in some archive somewhere, let
me know, I can send it.

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             reply	other threads:[~2023-01-15 19:11 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-15 19:09 ron minnich [this message]
2023-01-15 19:19 ` [TUHS] " Luther Johnson
2023-01-16  0:51 ` ron minnich
2023-01-16  1:59   ` Lawrence Stewart

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