11/45-1, Jay-0

From: Jay West <jwest_at_classiccmp.org>
Date: Fri Feb 18 20:45:16 2005

Tony wrote...
> First thing. Replace those burnt-out bulbs. You will go insane trying to
> sort out an 11/45 without a good panel. Period.
I used the lamp test switch, and was careful in trying to store/load values
that would be confirmed by lights that were definitely working. Confusing,
but works. I should fix it though... I'll start digging for a source for

> There are +5V on pin A2 of most of the connectors (maybe not the memory
> clots), ground is pin C2 and T1. -15V on B2. You need both those voltages
> for the CPU to run.
You mean I need both these voltages on every card that makes up the cpu I
assume, so I need to check each of those slots pins. I did check the
regulators directly, but I guess it's possible there's a broken wire not
getting those voltages up to the backplane.

> Can you tell me what boards (M numbers) you have in the CPU section of
> the backplane. Do you have the FPU and/or the MMU?
No FPU (and regulator configuration matches this), no MMU

Slots are used as follows:
1 (A,B) M930C
Slots 2-5 are open
6 M8100
7 M8101
8 M8102
9 M8103
10 M8104
11 M8105
12 M8106
13 - this slot is open
14 M8116
15 (c,d,e,f) M8109
Slots 16-25 are open
26 (a,b) M9200 leg 1
26 (c,d,e,f) M7800
27 (a,b) M9200 leg 2
27 (c,d,e,f) M7800
28 (a,b) ribbon jumper to MF11-L slot 1 (a,b)
28 M7228

Then the MF11-L
1 (a,b) ribbon jumper to cpu backplane slot 28 (a,b)
2 G110
3 G231
4 H214
X (a,b) don't recall the slot #, but it's the very last one - M930C

There's no other system units in the chassis.

> Jumpers on one of the boards, I am almost _certain_ of that.
Ok, I need to hunt up docs on the G110, G231, and H214 just to be sure then.

> Yes, it should, but only if you don't get a bus error. If you get an
> error, the address doesn't change.
I did get address errors when examining, but not when doing a load address.

> Bus errors are normally due to a device/memory not existing at the given
> address (I assume you've realised by now that all I/O devices are memory
> mapped).
Yup, seen that in prior dec docs a long time ago.

> I assume you've set the rotary switches sanely. I think you want the
> address one in one of the 'physical' positiions, the data one in the
> 'data path' position.
Yup, I read up on that. CONS PHYS... but I think I had the data one in the
"bus address" position. The processor handbook made it sound like that was
the right one to view addresses, and made it sound like the data path one
was just for output of the ALU.

> OK, what to do next. I asusme you don't have an M792 boot ROM (diode
> matrix card). If you do, stick it in (any SPC slot) and try reading it
> from
> the panel. This was a big help for me, being able to relate the light
> pattern to the diodes on the card.
I remember having one for an 8E when I first got my 8E, and traded it away
before realizing what it was :>

> Certainly check the PSU voltages. You should have +5V, +15V and -15V on
> the CPU backplane. I think your core needs +20V or something strange.
Voltages already checked at the regulator, I'll check each cpu slot for
those. I believe the MF11-L needed +5 and -15. I'll double check that.

> Check the ACLO and DCLO pins on the backplane too (thin yellow and puple
> wires on the power harness, I forget where they actually go). If one of
> those is low (0V), the CPU will be trying to do a power fail shutdown,
> and will not repsond to the panel in a sane way.
Gotcha, I'll look at that next.

> Do you have a KM11 maintenance PCB? In fact just what do you have?
Nope, sure don't. The only cards in the system are the ones mentioned above.
I do have a stock of unibus cards, terminator/loader cards, DZ11's, RX11's,

Thanks for the input!

Received on Fri Feb 18 2005 - 20:45:16 GMT

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