Fire up the iron...

From: Christopher Zach <cz_at_alembic.crystel.com>
Date: Mon Nov 27 21:27:06 2000

Ok, it's fall, it's cool, and I can finally start working on AI again.
With the cold weather, I can pop open a window instead of fighting a
losing battle with an 8,000 BTU AC unit.

Quick bit of status: Sitting in my computer room here at the house is:

AI (20/20 system, fully loaded with memory, passes all diags)
RM03 (Fully operational, need to dust off and purge)
RM80 (Operational, however currently unformatted)
RM03 (Logic problem in getting the heads to load)
TU77 (Doesn't work, why?)
TU77 (Spare for parts)

I've got a pair of RM02's, a TU45, and an RP07 sitting in storage. The
TU45 is a bit of a shambles, maybe with Dan's system as a plate I can
diagnose it someday. The RM02's will work on a 20, bit slower than an
RM03, but same format. The RP07 is in God knows what kind of shape (the
lid for it disintegrated on Interstate 40...). A dream would be to get
that drive operational and running as the system disk.

Once running, the systems will move to a place where power and AC is not
an issue. Till then, they run at my house.

The big problem with AI is that the tape MASSBUS is dead. I don't have a
clue as to why. Diagnostics are very vague, closest thing I get on the
controller is a control bus parity error/8915 bit fiddler error.
According to the limited TOPS20 diags, this could be anything.

So in order to figure this out, I've spent the evening pulling out the
DZ11's, the chaos controller and the Micon Ethernet card. In it's place
I have installed a pdp11/23+ for running pdp11 diagnostics on the RH11.

Yes, I know: 11/23's are Q-Bus and the RH11 is a Unibus tank. However
I've also got a Qunivertor, and it seems to be working (albeit in 18 bit
mode). At least I can fire up RSX11/M and begin walkin through tests on
the TU77/TM03/RH11. And I don't have to deal with the main CPU, the 18
bit fiddler, etc...

Thus my question: Did the tape drives work on AI before it went offline.
Somehow I seem to recall that they didn't, and this might be due to a
bad RH11 MASSBUS controller (as I have swapped in 2 other TM03
controllers with the same lack o results).

CZ
Received on Mon Nov 27 2000 - 21:27:06 GMT