Ok, so I have a working processor, and a basement full of peripherals. I'm
not sure which way to go with the rest of the build. I'm not really up on
DEC stuff I admit, so maybe others here can offer me some advice as to what
is the best way to proceed.
Background:
My 11/45 (11/45-CA actually) has the KB11-A processor, no FP. It's the older
style with the power distribution board on the back wall of the cpu cabinet
OK, mine is like that. I rebuilt the power harness to give me an extra 5V
feed from another regulator block to the expansion backplanes. The stock
system is a bit current-limited there.
rather than on top. However, it's also got the
newer 861A power control in
the bottom rather than the dual 860's in the top. There is the two H742A's
as well. I have one system unit installed - MF-11L in which is installed 8K
of core. In the cpu backplane there are three unibus slots which I believe
will take three quad? (C-F) boards. A&B in two of those slots are used for
Yes, they are standard SPC slots. Don't forget you'll have to play around
with the NPG jumper on the wire-side of the backplane if you put a DMA
device -- like an RX211 -- in one of those slots.
the unibus A to unibus B jumper, and A&B of the
last slot is the connector
to A&B of the MF-11L. The MF-11L has a 9312 in the last A&B slot. The SPC?
boards currently installed are two DL11's and a M7228. The ONLY board in
slot one is a 930C terminator in A&B. I have no MMU, so slot 13 is empty and
slot 14 has the M8116.
Pity. You really need that MMU. You are limited to 28kW of memory without
it.
Separately, I have a lot of peripherals to choose from. Scads of RL02's,
DSD440, LincTape II, RX01's, RX02's, RA81's, etc. I also have a BA11-KU with
a DD11-DK backplane in it.
Problem:
The unibus space on the cpu backplane is quite limited. At the VERY least I
have to keep one of the DL11's there, so that leaves me with two more unibus
slots for peripherals. I *THINK* that that standard controller for an RX02
or RL02 takes all 6 rows (Hex cards?). However, the DSD440 controller only
The RX02 controller (RX211) is a quad card and can go in the CPU
backplane. The RL11 is a hex card though.
takes slots C-F (quad?). The linctape II controller
also only takes C-F. So,
I think I could have a reasonable system by putting the DSD440 controller,
LincTape controller, and a DL11 and be done with it. However, I then am
limited to using core memory in the MF11. At the very best, I can get...
YOu have space for 3 'system units' behind the CPU backplane. The MF11,
IIRC, takes up 2 of them. You can fit a 4-slot backplane in as well. If
you are mildly eccentric, you can wire-wrap said backplane to be 2 quad
SPC slots, 2 hex SPC slots with MUD wiring on the top 2 connectors. That
might be enough for you.
what... 32K in a MF11? I think I can get the
additional core boards. But
correct me if I'm wrong but isn't sticking with core (max 32K) going to make
my operating system choices extremely limited? I'm guessing I can't run RSTS
or Unix on it with that kinda memory. vtserver I think requires a full load
of 128KW. On top of it all, the DSD440 takes most of the rack depth, as does
an RL02, so I've been advised against mounting anything above the /45 except
maybe the linctape.
I would only put a 'short' unit immediately above the 11/45 CPU, but
above that you can put an RL or something.
Possible solutions:
1) I just got a M7891 (64KW) off Ebay. I could yank out the MF-11L system
unit, yank out the DD11-DK from the spare BA11, and install the DD11 in the
cpu cabinet. I'd use the unibus memory M7891, ditch the core, and have a
fair number of slots left over in the DD11. However, there's problems with
this approach. I'd still be mounting stuff above the /45 (DSD440 & Linctape
at the least), and maybe an RL02. In other words, this would fix the memory
and unibus slot availability, but I believe I'd still be restricting the
airflow/cooling too much :\ Plus I'd need to find some of those rare Mate &
Lock connectors to get the DD11 into the /45 cabinet and do some power
The easiest place to find those connectors is to raid current-loop serial
cables....
harness building. I guess I might need one or more
regulators for this
approach as well. Then I'd have to find/buy a KT11-C to USE the M7891 I
think.... I'm probably talking about unobtanium stuff aren't I :|
-tony