• Mascor 132 Reference Manual ca. 1970

    From Al Kossow@[email protected] to comp.arch on Fri Apr 17 10:32:44 2026
    From Newsgroup: comp.arch

    A fun thing I came across on Tue in my stacks of random papers, the Mascor 132 Reference Manual ca. 1970. It was a startup that failed in
    the 1970 recession that a bunch of IBM ACS engineers went to before joining Amdahl. http://bitsavers.org/pdf/mascor I also added some
    related historical articles to http://bitsavers.org/pdf/amdahl/history
    --- Synchronet 3.21f-Linux NewsLink 1.2
  • From MitchAlsup@[email protected] to comp.arch on Sun Apr 19 01:35:29 2026
    From Newsgroup: comp.arch


    Al Kossow <[email protected]> posted:

    A fun thing I came across on Tue in my stacks of random papers, the Mascor 132 Reference Manual ca. 1970. It was a startup that failed in
    the 1970 recession that a bunch of IBM ACS engineers went to before joining Amdahl. http://bitsavers.org/pdf/mascor I also added some
    related historical articles to http://bitsavers.org/pdf/amdahl/history

    I took a look over the ISA and it is not as bad as one could imagine
    from taking a viewpoint embodied with computer knowledge from 1970.
    I found several tid-bits similar to the evolutionarily path My 66000
    has taken.

    Quadiblock might learn a thing or two by giving it a study, too.
    --- Synchronet 3.21f-Linux NewsLink 1.2
  • From Thomas Koenig@[email protected] to comp.arch on Sun Apr 19 06:58:48 2026
    From Newsgroup: comp.arch

    MitchAlsup <[email protected]d> schrieb:

    Al Kossow <[email protected]> posted:

    A fun thing I came across on Tue in my stacks of random papers, the Mascor 132 Reference Manual ca. 1970. It was a startup that failed in
    the 1970 recession that a bunch of IBM ACS engineers went to before joining Amdahl. http://bitsavers.org/pdf/mascor I also added some
    related historical articles to http://bitsavers.org/pdf/amdahl/history

    I took a look over the ISA and it is not as bad as one could imagine
    from taking a viewpoint embodied with computer knowledge from 1970.
    I found several tid-bits similar to the evolutionarily path My 66000
    has taken.

    Going through the document now (not very deeply)

    64 general purpose 32-bit registers, including for floating point
    and integer. In the data in bitsavers, it is not desribed how
    they handled 64-bit floating points (register pairs or otherwise).

    Having either a base register or the IP for addressing sounds
    familiar :-) They used segments as high bits of virtual
    addresses, so only 16 MB effective address space.

    Hexadecimal floats. Bah.

    32-bit instructions, only four instrucion formats.

    Six-bit constants instead of registers could be done.

    If I read it correctly (sadly, the instruction listing is
    missing from Bitsavers), the machine was similar to /360
    in that one operand was destroyed.

    Quadiblock might learn a thing or two by giving it a study, too.

    +1
    --
    This USENET posting was made without artificial intelligence,
    artificial impertinence, artificial arrogance, artificial stupidity,
    artificial flavorings or artificial colorants.
    --- Synchronet 3.21f-Linux NewsLink 1.2
  • From MitchAlsup@[email protected] to comp.arch on Sun Apr 19 18:21:45 2026
    From Newsgroup: comp.arch


    Thomas Koenig <[email protected]> posted:

    MitchAlsup <[email protected]d> schrieb:

    Al Kossow <[email protected]> posted:

    A fun thing I came across on Tue in my stacks of random papers, the Mascor 132 Reference Manual ca. 1970. It was a startup that failed in
    the 1970 recession that a bunch of IBM ACS engineers went to before joining Amdahl. http://bitsavers.org/pdf/mascor I also added some
    related historical articles to http://bitsavers.org/pdf/amdahl/history

    I took a look over the ISA and it is not as bad as one could imagine
    from taking a viewpoint embodied with computer knowledge from 1970.
    I found several tid-bits similar to the evolutionarily path My 66000
    has taken.

    Going through the document now (not very deeply)

    64 general purpose 32-bit registers, including for floating point
    and integer. In the data in bitsavers, it is not desribed how
    they handled 64-bit floating points (register pairs or otherwise).

    one should assume pairing of registers.

    Having either a base register or the IP for addressing sounds
    familiar :-) They used segments as high bits of virtual
    addresses, so only 16 MB effective address space.

    Hexadecimal floats. Bah.

    It was 1970...

    32-bit instructions, only four instrucion formats.

    Technically, IBM 360 only had 4 instruction formats...

    Six-bit constants instead of registers could be done.

    If I read it correctly (sadly, the instruction listing is
    missing from Bitsavers), the machine was similar to /360
    in that one operand was destroyed.

    Not in the way ISA describes how instructions were performed,
    and not in the control register model (sea of C registers.)

    Quadiblock might learn a thing or two by giving it a study, too.

    +1
    --- Synchronet 3.21f-Linux NewsLink 1.2