Hey Dwight,
I have an old KIM-1 that looks like it has multiple failures. It must have taken a pretty big shot, when it failed. I have replaced the failed 6530-002 with a Corsham 6532 replacement board. That did help, start to light up
one segment with a small c. I piggy backed all the memory and was able to get all the segments to light up, but just the lower half of the segments, although the C segment was not working. I could enter an address like 1111
and see the lower half of the 1's. If I entered a 6 or a D, segment C would not light up. I am unable to reproduce this by piggy backing all the memory again. So, now I am back to 1 small c, showing up.
With the Corsham 6532 replacement board. I am now seeing good signally coming coming out of U4. I am supper busy this week, but I want to start looking at U24 and U17 to start with. Any suggestions? I also suspect, that
the 6530-003 may be bad as well. As I had to replace the 6502 and the 6530-002, there is a good chance that the 6530-003 is also bad. Can I simply remove it while testing?
I did create a test board for the 6530-002 using a working KIM-1. I was able to access the I/O and ROM sections using K2 and K4. The ROM looked like possible A3 was bad, as it kept repeating good code every 8 bytes, replacing code that was supposed to be there.
I believe you worked on a diag board for the KIM-1. Do you still have one laying around? It might be fun to test this KIM-1 using a good diag board. I will not be able to do much until Next Sunday or Monday. Except maybe a quick fire up
from time to time.
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