PDP-11/45 RSTS/E boot problem

[Jerry Weiss]

On 1/5/19 2:58 PM, Fritz Mueller via cctalk wrote:
>> On Jan 5, 2019, at 8:07 AM, Noel Chiappa via cctalk <cctalk at classiccmp.org> wrote:
>>
>>> From: Fritz Mueller
>>> All the CPU, FPU, KT11, KW11, and RK11 MAINDECS are passing just fine.
>> Don't forget Vonada Maxim #12:
>>   "Diagnostics are highly efficient in finding solved problems.”
> Well, there’s wisdom there, for sure! :-)
>
> Last night I also managed to put a new RSTS image, sysgen’d with the non-overlapped DK driver, on a different physical pack.  It behaved exactly the same way on the real hardware (looping, counting up errors) on boot.
>
> So I think now overlapped vs. non-overlapped DK driver is not the issue, and media and image transfer fidelity are not the issue.  A memory or MMU problem would be consistent with what has been seen so far, so I may bark up that tree a little more today.
>
> Paul, any additional suggestions for things to look at in ODT to try and wring out more information on the specifics of the fault?
>
> I did get some MACRO CRC-16 sub-routines coded up last night while waiting for various transfers, so I think I’ll go ahead and finish up the standalone CRC dumper utility today.
>
> Lastly, a 5V-tolerant USB FIFO breakout board is supposed to show up in the mails today.  If that works out as simply as I hope to interface with a DR11-C, I should have a much better way to blast bits on and off the machine soon.
>
>      cheers,
>        --FritzM.
>
Along those lines if you have a spare disk pack, try putting RT11(FB,XM) 
on the machine and give it a workout.   This would exercise the machine 
a bit more than MAINDECS, though not as much as RSTS.

A few suggestions from my ancient history running RK11-C and a mix of 
DEC and Diablo Drives.  I regularly disassembled, moved cross country 
and reassembled PDP 11/34 and LSI 11/73 systems. I ran them in small 
rooms which housed saltwater tanks containing sea creatures.

  * Given the age of this equipment, double check all the ground
    connections between the cabinets, PDU's, drives, outlets and CPU.
  * Carefully check for breaks or problems with drive cables and
    terminators.
  * I believe you need a terminator in the RK11-C if the second disk bus
    is unused.
  * Try using the drive on the other bus if RSTS can be booted of from DK4.
  * Make sure you only have one LTC active if a DL11-W and a KW11 are
    both in use.
  * If you are not using a common PDU for the CPU, Drive and RK11-C
    power supplies, make sure they all powered from outlets on the same
    phase.
  * Don't leave the disk packs or drives near the tanks.  The squid have
    good aim and their ink isn't kind to electrical devices.

     Jerry