[TUHS] Re: pdp11/34 can't boot. help us !

[John Holden]

The machine sounds a scary mix of Unibus and Qbus peripherals (a real Heath
Robinson!). Given you cannot deposit/examine memory and get correct results,
the bootstrap will halt because it runs some diagnostics (including memory)
before it attempts to boot a device.

The first step it is to strip down the system to the first system unit. You
can still leave all the cards in, just remove the unibus jumper from slot 9
and move the terminator M9302 into slot 9 (a-b). For good measure, I'd also
remove the M8217 from slot 9 (c-f) and put in a bus grant continuity card if
you have one. Since it's (now) the last slot, it shouldn't matter if the
grant card is missing.

Then try your memory deposit/examine test.

I'm assuming here that you have tested all the power supply voltages as it
appear that you have a fairly loaded system. Have a look at the following site
for more hints:-

	http://www.psych.usyd.edu.au/pdp-11/hints.html