Some pointers needed on a 11/70

From: The Wanderer <>
Date: Sun Jan 6 14:44:36 2002

Pete Turnbull wrote:
> > I swapped the Unibus map and the cache control board, and the machine
> > behaves
> > apparently much better.
> Hmm.. Lots of DEC CPU backplanes have dedicated slots for various things,
I actually did mean that I exchanged them for 2 other, identical boards.

> and the position/order of the boards is very important. I don't know if
> the 11/70 is like that, but I'd not be at all surprised if it were. Have
> you checked that everything is in exactly the right place? If you've
> removed any optional boards, have you checked in case any jumpers need
> replaced?

I did, all the jumpers are where the are supposed to be.

> > switch between tabs 1 & 2 of the M9312) and it goes into a sort of loop
> > after
> > a second or so.
> Do you mean that someone swapped the wires from their normal places, or
> that someone added a switch that wouldn't normally be there?
At the bottom of the console in the metal fram, there is a small
made which leads directly to the M9312 tab1 & tab2. This looks like a
button' bootstrap and the previous owner made it apparently to have a
(re)start of the machine when needed.

> > When pressing halt, the address display ends in 344,
> > while the
> > data display shows 116.
> >
> > Also memory location 400000 through 477777 are accessible via the
> > console and
> > I can dump data and read from it.
> That's an unusual address, and it's only 32K bytes (16KW). You said you
> had two 64KW boards. What type are they? They probably have switches to
> set their base addresses. Are these set correctly? It would be worth

There are 2 M8728 boards in the memory box.

> trying just one, set to address zero, and see if that improves things.
> Start with the minimum in the system, and build it up as you get things
> working.

> > At 344 (addr) and 116 in the data display. No idea if this a valid value
> > though...
> It's an odd sort of address. I'd expect it to stop at an address in the
> ROM. If you had to halt it manually, it must have been running in a loop.
> Why that address, I have no idea, because according to the M9312 manual,
> it only runs code from ROM until it has booted some device. According to
> the M9312 manual, it runs various CPU instruction tests, then tests memory
> from 1000 to as high as it can go (up to 28KW), then tests the cache. It
> will halt if it gets an error in any of the memory or cache tests, but you
> can press CONTINUE to ignore the fault and carry on.
> > > Do you have the manual for the M9312? There are several ROMs that
> might
> > Yes, the 9312 has the 233 type rom (11/70 diagnostic, so this is ok).
It is the 23-233F1 diag rom.

> Well, you ought to set it to the correct value, obviously, but I've no idea
> what would happen if you set it too high or too low. Yes, it's the high
> limit.
All the jumpers on the memory boards are having their default positions,
and the switches on the databuffer board are all open. The box has the
memory boards, the M8164 data buffer board and the M8168 address buffer
There are also 2 controller 'A' and 2 controller 'B' boards.
I have field drawings of the memory boards, but not of the address
buffer and
data buffer board.


The Wanderer                      | Politici zijn gore oplichters.                  | Europarlementariers: zakkenvullers      | en neuspeuteraars.
Unix Lives! M$ Windows is rommel! | Kilometerheffing : De overheid
'97 TL1000S                       | weet waar je bent geweest!
Received on Sun Jan 06 2002 - 14:44:36 GMT

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