PDP-11/34a hung bus problem -> solved.

E. Groenenberg ed at groenenberg.net
Thu May 19 15:23:48 CDT 2016

Well, I feel somewhat stupid, but the problem with the hung bus is solved.

The cause of it? no jumpers on the backplane to bypass the battery backup.

The machine had a BBU regulator, but it was removed as I don't have the
battery pack. So, after adding the 3 jumpers the NPG signal was cleared
after a cntrl+halt and characters could be printed when deposited at
address 777566 (with memory in the backplane).

So, next step is to add a RL11 controller and see if it will boot RT-11.
But that is for the weekend....

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