MITS 8800 Question - CP/M

This is a discussion on MITS 8800 Question - CP/M ; Is anybody out there who knows what were the I/O ports used by the MITS 8800 Altair? I am working recreating the source code of an old program, and I found a table of bytes. After much head scratching, I ...

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  1. MITS 8800 Question

    Is anybody out there
    who knows what were the I/O ports used by the MITS 8800 Altair?

    I am working recreating the source code of an old program, and I found
    a table of bytes.

    After much head scratching, I think that it must be used to specify
    the I/O ports used, and their characteristics?

    So, does anyone recognizes the following values:

    Load$Options:
    ; +---------------------> Octal Channels
    ; | +----------------> Status Bits Active?
    ; | | +--+-----> Octal Masks
    ; | | | |
    db 20Q, 312Q, 1, 2 ; 2SIO
    db 20Q, 312Q, 1, 2 ; (Twice?)
    db 0, 302Q, 1, 200Q ; SIOA,B,C (not REV.0)
    db 6, 302Q, 1, 200Q ; ACR
    db 40Q, 312Q, 200Q, 200Q ;
    db 4, 312Q, 2, 1 ;
    db 44Q, 312Q, 100Q, 100Q ; 4PIO ?

    Yours Sincerely,
    Mr Emmanuel Roche


  2. Re: MITS 8800 Question

    "Mr Emmanuel Roche, France" wrote in message
    news:81265155-723b-4f54-aeac-b75fb95142eb@a22g2000hsc.googlegroups.com...
    > Is anybody out there
    > who knows what were the I/O ports used by the MITS 8800 Altair?
    >
    > I am working recreating the source code of an old program, and I found
    > a table of bytes.
    >
    > After much head scratching, I think that it must be used to specify
    > the I/O ports used, and their characteristics?
    >
    > So, does anyone recognizes the following values:
    >
    > Load$Options:
    > ; +---------------------> Octal Channels
    > ; | +----------------> Status Bits Active?
    > ; | | +--+-----> Octal Masks
    > ; | | | |
    > db 20Q, 312Q, 1, 2 ; 2SIO
    > db 20Q, 312Q, 1, 2 ; (Twice?)


    MITS 88-2SIO, Ttwo Serial I/O ports

    > db 0, 302Q, 1, 200Q ; SIOA,B,C (not REV.0)
    > db 6, 302Q, 1, 200Q ; ACR


    Cassette recorder interface.

    > db 40Q, 312Q, 200Q, 200Q ;
    > db 4, 312Q, 2, 1 ;
    > db 44Q, 312Q, 100Q, 100Q ; 4PIO ?


    Four port parallel card.

    Give this a gander, especially the "Peripheral Cards (General)", about half
    way down.

    http://www.altair32.com/Altair32links.htm

    Also try the "Specifications" page (link on left edge of each page) where it
    talks about the SIO and 2SIO.

    - Bill


  3. Re: MITS 8800 Question

    On 11 avr, 11:55, "Mr Emmanuel Roche, France"
    wrote:

    > Is anybody out there
    > who knows what were the I/O ports used by theMITS8800Altair?
    >
    > I am working recreating the source code of an old program, and I found
    > a table of bytes.
    >
    > After much head scratching, I think that it must be used to specify
    > the I/O ports used, and their characteristics?
    >
    > So, does anyone recognizes the following values:
    >
    > Load$Options:
    > ; * * * * * * * *+---------------------> Octal Channels
    > ; * * * * * * * *| * *+----------------> Status Bits Active?
    > ; * * * * * * * *| * *| * * * +--+-----> Octal Masks
    > ; * * * * * * * *| * *| * * * | *|
    > * * * * db * * *20Q, 312Q, * *1, 2 * * *; 2SIO
    > * * * * db * * *20Q, 312Q, * *1, 2 * * *; (Twice?)
    > * * * * db * * * *0, 302Q, * *1, 200Q * ; SIOA,B,C (not REV.0)
    > * * * * db * * * *6, 302Q, * *1, 200Q * ; ACR
    > * * * * db * * *40Q, 312Q, 200Q, 200Q * ;
    > * * * * db * * * *4, 312Q, * *2, 1 * * *;
    > * * * * db * * *44Q, 312Q, 100Q, 100Q * ; 4PIO ?


    So that other people could know the answer, here is what I received:

    > IO DEVICE TABLE:
    >
    > 2SIO WITH 2 STOP BITS
    > 2SIO WITH 1 STOP BIT
    > SIO BOARD
    > ACR CASSETTE
    > 4PIO BOARD
    > 88PIO
    > HIGH SPEED TAPE READER


    > I respectfully ask that you not post my email address on the newsgroup...


    Hello, "anonymous"! Many thanks for your answer, since I have never
    seen (except on pictures) a MITS 8800... So, thanks to you, we finally
    know what where those mysterious 3 last devices.

    Too bad that such a knowledgeable man as you don't participate more in
    the comp.os.cpm Newsgroup, contrary to someone whose mantra is: "30
    years ago, I did it..." but was, as usual, unable to answer this
    hardware question, while publicly saying that he has several MITS 8800
    systems...

    Yours Sincerely,
    Mr Emmanuel Roche


  4. Re: MITS 8800 Question

    Since the last message, my "anonymous" correspondent explained me why
    there were 2 identical 2SIO lines:

    > > * * * * db * * *20Q, 312Q, * *1, 2 * * *; 2SIO
    > > * * * * db * * *20Q, 312Q, * *1, 2 * * *; (Twice?)


    According to him, the idea was that users were selecting the number of
    stop bits by entering them via the "sense switch" (a set of toggles
    that was used to enter/read stuff into the MITS 8800 one byte at a
    time).

    Conclusion: all my questions have now been answered. But not by
    Allison "30 years ago..." Parent, the "Hardware Dinosaur".

    Yours Sincerely,
    Mr. Emmanuel Roche, France


  5. Re: MITS 8800 Question

    On May 9, 8:28 am, "Mr Emmanuel Roche, France"
    wrote:

    > Conclusion: all my questions have now been answered. But not by
    > Allison Parent, the [rude comments deleted].


    In another thread, on Furgerson Big Boards, Mr. Roche also insulted
    Ms. Parent. I agree with my colleages who responded there, that such
    posts are clearly obnoxious, inaccurate and unacceptable. Cease and
    desist such posts.

    Herb Johnson
    retrotechnology.com

    Herbert R. Johnson, New Jersey USA
    http://www.retrotechnology.com/herbs_stuff/ web site
    http://www.retrotechnology.net/herbs_stuff/ domain mirror
    my email address: hjohnson AAT retrotechnology DOTT com
    if no reply, try in a few days: herbjohnson ATT comcast DOTT net
    "Herb's Stuff": old Mac, SGI, 8-inch floppy drives
    S-100 IMSAI Altair computers, docs, by "Dr. S-100"

  6. Re: MITS 8800 Question

    On May 9, 1:45*pm, Herb Johnson wrote:
    > On May 9, 8:28 am, "Mr Emmanuel Roche, France"
    > wrote:
    >
    > > Conclusion: all my questions have now been answered. But not by
    > > Allison *Parent, the [rude comments deleted].

    >
    > In another thread, on Furgerson Big Boards, Mr. Roche also insulted
    > Ms. Parent. I agree with my colleages who responded there, that such
    > posts are clearly obnoxious, inaccurate and unacceptable. Cease and
    > desist such posts.
    >
    > Herb Johnson
    > retrotechnology.com
    >

    ---
    Oh, I don't know, Herb, maybe we should let him ramble; if he's too
    dumb to realize that someone who asks for help as often as he does
    should not antagonize the people whom he's asking with his insults and
    spam postings, maybe we can all do him a service by teaching him that
    lesson.

    But maybe his government should speak to him about confirming the
    stereotypical reputation of the French for being rude and ignorant...
    ;-)

    m

  7. Re: MITS 8800 Question

    On May 10, 9:40 am, MikeS wrote:
    > But maybe his government should speak to him about confirming the
    > stereotypical reputation of the French for being rude and ignorant...


    Oh, c'mon, how long have you been on Usenet. Someone who has a
    name entry of "Mr Emmanuel Roche, France" is obviously an
    anti-France pommie who is deliberately trying to reinforce the
    British stereotype of the French.

    So if someone makes the above point, Manny Rusk ... or whatever his
    real name is ... will quite obviously be thrilled that his plan is
    working.

  8. Re: MITS 8800 Question

    On Fri, 9 May 2008 05:28:35 -0700 (PDT), "Mr Emmanuel Roche, France"
    wrote:

    >Since the last message, my "anonymous" correspondent explained me why
    >there were 2 identical 2SIO lines:
    >
    >> > * * * * db * * *20Q, 312Q, * *1, 2 * * *; 2SIO
    >> > * * * * db * * *20Q, 312Q, * *1, 2 * * *; (Twice?)

    >
    >According to him, the idea was that users were selecting the number of
    >stop bits by entering them via the "sense switch" (a set of toggles
    >that was used to enter/read stuff into the MITS 8800 one byte at a
    >time).
    >
    >Conclusion: all my questions have now been answered. But not by
    >Allison "30 years ago..." Parent, the "Hardware Dinosaur".


    Well Hardware Dinosaur I may be then again I've doing work with
    Analog Devices Blackfin which is very anti-dinosaur.

    However your explanation ignored the answer I did give and also
    your lastest comment is incorrect. You never used a front pannel
    machine so you haven't the first clue how the "sense" switches were
    used and how the user interacted with it. So heres a cluebyfour
    for you...

    MITS software used the "sense" switches to select things at generally
    two times. Oen was during the secondary boot or during program load
    after you toggeled in the initial booter. FYI": the hand loaded
    booter was specific tho the load device being used{ TTY, PTR, ACR or
    disk}. After that loader was in memeory you would use the frotn
    pannel to get the the start address, then set the sense switches and
    hit RUN. The loader would load the program for example MITS BASIC
    and that program would read the sense switches for the IO to be used.
    There would be only one setting and not multiple entries.

    The second case less often used is after load and initial
    configuration whith the program interacting with the terminal you
    could inform the program to use another device for output. MITS
    Programming Package II did this and it was awkward.

    But hey this Dinosaur actually still has an ALTAIR and software from
    back then and really did things with it.

    As to what I've contributed to the net.. you can't know as I don't
    keep a web page. I have contributed to many web pages and
    Tim Olmstead got many megabytes of code and pounds of paper
    via surface mail to help in the building of that site which Gaby
    still maintains.

    Reminder: I try NOT to help you as your an abrasive fool. Those that
    I can and do help are often taken offline so that we have the needed
    bandwidth to seriously delve into the topic. Now if you don't want
    to end up shunned, plonked or relagated to the killfile consider your
    comments. Myself I've been on the net long enough that one more
    troll is easily filtered. It's not that hard to change "french luser"
    to your current nom de plume in the killfile.


    Allison
    >
    >Yours Sincerely,
    >Mr. Emmanuel Roche, France



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