PDP-11/45 RSTS/E boot problem

Jay Jaeger cube1 at charter.net
Wed Feb 13 12:20:09 CST 2019

On 2/13/2019 1:43 AM, Fritz Mueller via cctalk wrote:
> Put the M795 out on an extender, loaded 167777 in RKBAR, and had a look around with a logic probe.  Narrowed it down to E34 (a 7430 8-input NAND).  Pulled, socketed, replaced, and off she goes!
> I can now successfully boot and run both V6 Unix and RSTS/E V06C from disk.
> *THAT* was a really fun and rewarding hunt :-)  First message in the thread was back on Dec 30, 2018.  Lots of debugging and failed DRAM repairs, then the final long assault to this single, failed gate...
> Thanks to all here for the help and resources, and particular shout-outs for Noel and Paul who gave generously of their time and attention working through the densest bits, both on and off the list.
> I predict a long happy weekend and a big power bill at the end of the month :-)
>     cheers,
>       --FritzM.

Congratulations.    As another poster mentioned, it has been fascinating
to watch and learn, day by day, as you worked on the problem with Noel
and Paul's help.

And I learned a little bit more about my 11/45 (that it indeed had had a
processor field upgrade), which I had not looked at very closely before.

Maybe that story about FE's using Unix as a test to confirm operation
even when diagnostics said the machine was OK was not so much just a

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