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Thread: Simulating PDP-8 on a PDP-11?

  1. #11
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    Quote Originally Posted by AK6DN View Post
    Richie Lary of the PDP-8 world
    I am 'acquainted' with Richie - we both worked in CXO for years. Years ago he gave me a VT05 that he was storing under his deck.
    When he left DEC and cleaned out his office, he threw a bunch of stuff in a bin, so I rummaged through it to salvage some things. One was a custom "logic analyzer" that he designed, circa 1985(?). Our CXO site was doing storage controllers, including the UDA50, KDA50, and HSC50, which all used a 2901 bit-slice architecture with dual sequencers (which I think Richie architected). Richie needed a logic analyzer, but the commercial choices didn't do what he wanted. So he designed his own, nicknamed 'MAD' (need to look up what the acronym stood for). It consists of two quad-height Q-bus cards plugged into an 11/23, with ribbon cables to the UUT. Some SW ran on the 11/23 under RT-11 - Harry Siegler wrote part of that support SW. It was used for lab debugging of the HSC50. Another key engineer on the HSC project was Tom Fava.
    Anyway, I still have those two logic analyzer boards. Only a few were built - it wasn't a 'product', just used in our lab.

    Pete

  2. #12
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    Don,

    Thanks for pointing to that interview - it should be required reading for anyone with an interest in early DEC gear. I'm looking forward to Part 2.

    I'm also curious to know if CHM (or anyone else) ever did an extensive interview with Tom Stockebrand, whose work included the tape drives for the TX-0, the LINC and DECtape.

  3. #13
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    Quote Originally Posted by jackrubin View Post
    Don,

    Thanks for pointing to that interview - it should be required reading for anyone with an interest in early DEC gear. I'm looking forward to Part 2.

    I'm also curious to know if CHM (or anyone else) ever did an extensive interview with Tom Stockebrand, whose work included the tape drives for the TX-0, the LINC and DECtape.
    Here's a blurb on Tom, copied from here: http://www.decconnection.org/digitalstechnology.htm
    Code:
    One of my all-time favorite technologists arrived as a result of this... an amazing guy named
    Tom Stockebrand. He was, if memory serves, actually a Chemical Engineer and was hired to
    build our first "integrated circuit" known as a diode strait. It was meant to allow our modules
    to derive logic power (-3 volts) with a single component instead of the handful of resistors 
    and expensive diodes that were required at the time. Ken tells the story that the week the 
    project finally delivered the first devices the price of diodes dropped to around 14 cents... 
    making the diode straits our first "technology/financial failure"... the important thing is that 
    Tom - the technologist - stayed on and created some of the most innovative products the 
    company ever built!  You know some of them...the DECwriter(s), the VT-05, VT-50 and 52,
    and on and on...)
    I never met Tom while I was in Maynard/Tewksbury, but I did meet him on a business trip out
    west when he had taken over running the DEC Albuquerque facility in New Mexico. He was never
    one that liked the in-fighting between all the groups in Massachusetts, so he headed out west
    to run that facility when he got the chance. The were producing the VT10x there at the time.
    He also had an advanced development terminals/graphics group that he was running.

    The main focus of our trip at the time was to go out to Stanford and visit with a researcher
    at SLAC named Prof Forrest Baskett concerning a grad student of his that developing a new
    kind of graphics terminal, and he thought it might be of interest to DEC. The grad student
    was Andy Bechtolsheim and it was the SUN (Stanford University Network) model one terminal,
    built around a new fangled chip called the MC68000 that was programmed to do 'BITBLT'
    operations. This was about 1980 or 1981 as I recall. https://en.wikipedia.org/wiki/SUN_workstation

    Don

  4. #14
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    Found this in the CV of someone on the net:

    April 1978
    Digital Equipment Corp., Albuquerque, New Mexico, c/o Tom Stockebrand.
    Advised on the use of grey-scale and anti-aliasing to multiply effective screen resolution for a project developing a high performance graphics terminal.


    Wasn't until 1980 that I met Tom in Albuquerque, and I'm sure we talked to him about his work on this project, as that is similar to what we in Tewksbury PDP-11 advanced development group were working on at the time. We were using OTS portrait mode monitors (Ball Bros IIRC) and were mainly working on the graphics processing subsystem.

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