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Re: IMSAI 8080

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  • joshbensadon
    ... Good move! 8212 is it. ... Very cool, reverse engineering! It doesn t get better than that! Is there a main controller chip it s based on?
    Message 1 of 61 , Apr 3, 2013
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      --- In midatlanticretro@yahoogroups.com, "DanielB" <danlb_2000@...> wrote:
      > Yeah, I even went as far as grounding the resistors to the LEDs to be sure they light, and they did, so it looks like it's the 8212.

      Good move! 8212 is it.

      > I have a Technical Design Systems system monitor board that I want to get running next, but I am waiting for my order of replacement tantalums to come in before I proceed on that. I also have a disk controller that I have not been able to find any documentation on so I am in the process of tracing out the circuit for that board and I will probably dump the EPROM to see figure out how it's software works.
      >

      Very cool, reverse engineering! It doesn't get better than that!
      Is there a main controller chip it's based on?

      :)J
    • DanielB
      Yep, front panel is working good now. One odd thing I have run into is that from the Zapple monitor I can write to the SMB s onboard RAM, but I cannot write to
      Message 61 of 61 , May 14 1:24 PM
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        Yep, front panel is working good now. One odd thing I have run into is that from the Zapple monitor I can write to the SMB's onboard RAM, but I cannot write to the RAM on the memory board but I can write to the memory board from the front panel.

        Dan

        --- In midatlanticretro@yahoogroups.com, joshbensadon <no_reply@...> wrote:
        >
        >
        >
        > --- In midatlanticretro@yahoogroups.com, "DanielB" <danlb_2000@> wrote:
        > >
        > > After bad chips I finally got the front panel working, and after a couple bad tantalum caps on the SMB I also got that working. Very exciting when I got the Zapple monitor prompt!
        > >
        > > https://lh6.googleusercontent.com/-uQShOzInDeE/UZFoWnYYpsI/AAAAAAAACII/80vupyb6Psc/w883-h662-no/IMG_3933.JPG
        > >
        >
        >
        > Daniel,
        >
        > That's looking great! Very well done :)
        >
        > Can you now Examine/Deposit via the front panel?
        >
        > :)J
        >
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