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    From Folkert van Heusden@folkert@vanheusden.com to alt.sys.pdp11 on Tue May 5 20:22:30 2026
    From Newsgroup: alt.sys.pdp11

    Hi,

    For a few years I occasionally work on a PDP11/70 emulator. It runs on linux/windows/mac and even an ESP32-S3 microprocessor.

    I have no idea how fast or slow a real PDP11/70 is in reality so I have no idea about the speed of my emulator. To resolve that I created a simple benchmark that runs at least on simh and also on other emulators
    (including mine). ersatz11 won't work though: no output and it hangs.
    The benchmark can be found at: https://vanheusden.com/emulation/PDP-11/ benchmark/

    My questions now are:
    * how can I get the benchmark to run on ersatz11?
    * does anyone have a real pdp11/70 who is willing to give my benchmark a
    try? it only needs 8 kB of RAM and an KW11-L to run - no floating point or isks required. it is a "bare metal" program so no OS is required either.
    after 10 seconds it outputs the count and HALTs.


    regards

    p.s. my emulator can be found at https://vanheusden.com/emulation/PDP-11/
    kek/
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  • From Dave McGuire@mcguire@lssmuseum.org to Folkert van Heusden on Thu May 7 21:23:24 2026
    From Newsgroup: alt.sys.pdp11

    On 5/5/26 16:22, Folkert van Heusden wrote:
    For a few years I occasionally work on a PDP11/70 emulator. It runs on linux/windows/mac and even an ESP32-S3 microprocessor.

    I have no idea how fast or slow a real PDP11/70 is in reality so I have no idea about the speed of my emulator. To resolve that I created a simple benchmark that runs at least on simh and also on other emulators
    (including mine). ersatz11 won't work though: no output and it hangs.
    The benchmark can be found at: https://vanheusden.com/emulation/PDP-11/ benchmark/

    My questions now are:
    * how can I get the benchmark to run on ersatz11?
    * does anyone have a real pdp11/70 who is willing to give my benchmark a
    try? it only needs 8 kB of RAM and an KW11-L to run - no floating point or isks required. it is a "bare metal" program so no OS is required either. after 10 seconds it outputs the count and HALTs.

    We have a running PDP-11/70 at LSSM; we can try it there. But I
    myself am not too interested in toggling in such a large program. ;)
    (not that it's large, but you know what I mean!) Maybe set it up to run
    under RT11-SJ?

    -Dave
    --
    Dave McGuire, President/Curator
    Large Scale Systems Museum
    New Kensington, PA
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