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Thread: CP/M or similar OS for 64K Z8002?

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    Default CP/M or similar OS for 64K Z8002?

    I was going through my hellbox of ICs looking for something when I ran across a couple of Z8002 CPUs. Are ther any OSes (CP/M perhaps) for the small-model (64K) Z8000?

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    CP/M-8000? Get it from Gaby's page:

    http://www.cpm.z80.de/binary.html#operating

    Source code is available here:

    http://www.cpm.z80.de/source.html

    --T
    Teach your children how to think, not what, and hold 'em close, not tight.
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    Please visit the Vintage-Computer Wiki. Contributers welcome.

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    I took a peek at it, Terry--it's heavily segmented stuff, so won't work on the Z8002.

    It's hard to think of 64K as "small" in terms of CP/M, but perhaps that memory space on the Z8000 architecture is just too small to do any useful work.

    Ah well, back in the hellbox.

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    Segmented? UGH! Might as well just work with 8088 DOS...

    --T
    Teach your children how to think, not what, and hold 'em close, not tight.
    _____________________________________________

    Please visit the Vintage-Computer Wiki. Contributers welcome.

  5. #5

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    Hi
    The CP/M-8000 was made from CP/M-68K. This was all
    C code except the low level stuff.
    I was one of the people that got the code for the 8000
    running on my Olivetti M20.
    My understanding was that it was actually first written
    on a M20 at Zilog.
    You could always get a Z8001. They are quite similar for
    the pins. The trick would be to create the needed memory
    space.
    There isn't much low level code on Gaby's page but I could
    extract much of it from the library that I have on my M20.
    You'd need to disassemble it though, it is just an object
    code library.
    The notes on the source seem to indicate that it could be
    done in 256K of RAM but I suspect they are assuming that
    much of the machine access code is in ROM.
    I do think it could be done on a Z8002 with some bank
    switching tricks.
    The Z8002 can directly access 128K of RAM if you split
    the instruction and data spaces. The only disadvantage
    of doing this is that you'd need a way to mape the instruction
    memory into data space to load the RAM and then switch
    it back to the 128K mode to run the code.
    The M20 does this but handles it bu using different segments.
    One could do this with a bank switching trick on the Z8002.
    Dwight

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    Hi Dwight! I was thinking about a throw-together 64K system using what was in my hellbox. Not worth the trouble, considering that there's not much in the way of software applications for such a rig.

    Back to the hellbox with 'em.

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    Smile

    CP/M-80 or v2.2 (or whatever you want to call it) runs easily in 64k! I believe that Operating system will run on the 8080 systems as well as the Z80 systems. Okay so the Z8002 is a 16bit CPU which precedes the Z8001? No mention of CP/M for this Olivetti M20 which has a Z8001 processor - Olivetti wrote it's own Operating System call PCOS, perhaps worth checking out the Vintage Computer Museum to see if CP/M was made for those Zilog 16bit based processors.

    Otherwise Emmanuel Roche maybe able to help - they've posted some stuff in here and seems to know a bit about the different forms of CP/M.

    It be nice if those 16bit processors were all backward compatible with the Z80 processors - if that were the case, then a CP/M shouldn't have problems running in it - it would just need to be customised though.

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    The Z8002 is just as old as the Z8001. Zilog's approach was to offer two versions--one segmented, the other not that would fit in a 40 pin DIP. Seems in retrospect to be pointless--my Z8002s are are PLCC packages.

    Regardless, the problem is once you get what passes for an OS going, what do you do for software? Do you run DDT all day and look at the pretty dumps?

    My hope was that if there were some active non-seg Z8002 OS that there would also be some small amount of applications.

    In fact, both Zilog and AMC offered Z80-to-Z8000 translation programs. Like the Intel 8080-to-8086 translator, it resulted in immediate bloat unless you were willing to hand-optimize the result. Much early MS-DOS code was auto-translated and tweaked 8080 CP/M code. I know that much of SuperCalc for the PC was, for example. Early (e.g. 3.3) versions of Wordstar for DOS probably also were.

    But feh, with no software, what good is a CPU?

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    Chuck(G) wrote:

    The Z8002 is just as old as the Z8001. Zilog's approach was to offer two versions--one segmented, the other not that would fit in a 40 pin DIP. Seems in retrospect to be pointless--my Z8002s are are PLCC packages.

    Regardless, the problem is once you get what passes for an OS going, what do you do for software? Do you run DDT all day and look at the pretty dumps?

    My hope was that if there were some active non-seg Z8002 OS that there would also be some small amount of applications.

    In fact, both Zilog and AMC offered Z80-to-Z8000 translation programs. Like the Intel 8080-to-8086 translator, it resulted in immediate bloat unless you were willing to hand-optimize the result. Much early MS-DOS code was auto-translated and tweaked 8080 CP/M code. I know that much of SuperCalc for the PC was, for example. Early (e.g. 3.3) versions of Wordstar for DOS probably also were.

    But feh, with no software, what good is a CPU?

    I agree with that problem that if there's no support for that CPU, it's not worth pursuing, however I find it amazing that a CPU like that would get no support - after all Z80s were popular processors!

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    IIRC, the 8001, 8002s, etc were mainly used for specialized applications, such as telco switching equipment, etc.

    --T
    Teach your children how to think, not what, and hold 'em close, not tight.
    _____________________________________________

    Please visit the Vintage-Computer Wiki. Contributers welcome.

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