Next project: 11/24. Does it need memory?--Progress-ish

Chris Zach cz at
Fri Oct 23 19:07:49 CDT 2020

And "in the meantime" I figured something was wrong on the Unibus, so I 
pulled all of the cards except CPU, memory, and the 9302 terminator.

Still flunks in any memory references in ODT. Weird.

Then I pulled the memory card so it was just the CPU. Same thing.

Then I figured might as well put the memory back, and pull the 
terminator. Sure enough, memory board LED goes red....

But the CPU can now read and write to memory locations via ODT. Loading 
100 into location 0 works, and I can read location 0 and now see 100.

That's weird. It looks like the problem is using a 9302 terminator 
instead of a 9312. Is there differences between the 930, 9302, 9312, and 
other terminators by chance (yes, it's in the last slot in the AB slot).

Weird. But getting closer every day...


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