https://web.archive.org/web/20130521183231/http://jack.hoa.org/hoajaa/BurrMain.html

has the burroughs info.

On Sun, Jan 15, 2023 at 11:09 AM ron minnich <rminnich@gmail.com> wrote:

> 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:
> http://jack.hoa.org/hoajaa/Burr126b.html
>
> 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.
>
>
>