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Examine using Front Panel - problem

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  Examine using Front Panel - problem by Bill Degnan - 09/06/2009 20:01
This is a note to self. I have an Altair mentioned elsewhere on this web site, SN 220744K, and the front panel has been mod-ed to with both IMSAI and Altair front panel connectors so either CPU interface card can be used.

When the Altair card in installed, examine does not work. Here is a substitute for examine in the mean time

assume you're starting from 000 000 but you want to examine what's in c000.

deposit load the following:
000 303 jmp [a7, a6, a1, a0 up]
000 000 lower [all down]
000 300 upper [ a7, a6 up] = c000
reset
put all toggles down
single step = watch for a15, a14 up = c000
now that you have jumped to c000, you can use the examine next.

NEXT:
try system with imsai CPU card, see if examine works. If yes, then it's the cable, if no, then it's the front panel (someplace).

See also post about the power supply capacitor for this system, needs replacing.

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  Examine using Front Panel - correction by Daniel Roganti - 09/25/2009 08:03
Correction,

I actually made an adapter cable to allow use of either an Altair cpu card or Imsai cpu card. This isn't mounted inside the Altair, just a loose cable which you can move from machine to machine. I have it here at home to fix your other Altair :)

I can make another one to let you try it too.

The next time I visit we can look at that particular Altair again to see wht the Examine function quit working. I'm hoping it's a loose connection, if not maybe another chip went bad. I'll bring some more just in case.

=Dan Roganti

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