20 Jan
2002
20 Jan
'02
8:57 p.m.
On Jan 19, 22:35, jkunz(a)unixag-kl.fh-kl.de wrote:
Only the first 3 slots are Q/CD. The other 5 slots are
Q/Q in serpentine
bus grant wiring. Tony said that the memory should be in the first
slot.
Lothar later said this is an H9276-A. That's a straight backplane, all
Q22/CD. It seems he has a BA11-S not a BA23 :-)
BTW, DEC normally recommended all comms and network cards go after the
memory, tapes next, then disks.
AFAIK some 11/73 labeld boxen where sold with a 11/83
CPU in the first
slot and the memory in the second.
It's the order of the boards (and the boot ROMs) that make it 11/73 or
11/83, not the circuit board. Though original 11/73s are 15MHz and
original 11/83s are 18MHz.
AFAIK a 11/83 CPU can use QBus and (or?) PMI memory.
If it is
configured with QBus memory it is calld a "11/73". But keep in mind
that there is a "real" 11/73 CPU (M8192 = KDJ11-A).
That's a dual-height board, CPU only, with no boot ROMs, LTC, or SLUs. It
was only sold as an OEM product or as an upgrade to 11/03 or 11/23 (not
11/23+ or microPDP-11/23) systems. Whilst it is a "real 11/73", it's no
more "real" than any other :-)
Hmm. Are there Q/CD only BA23 backplanes?
No. There are straight Q/CD and serpentine Q/Q backplanes of the same size
but they're only used in other boxes (like BA11-N and BA11-S) or sold as
OEM units.
I never saw a front panel like that, but your
assumption sounds right.
All my front panels have only one disk write protect / online switch.
The BA23 was only rated for one hard disk and either a TK50 or an RX50, but
the BA123 (which uses the same panels) was rated for up to 4 MSCP devices.
That's why the WP and ONLINE switches and LEDs are on a subassembly, so
you can add another one.
--
Pete Peter Turnbull
Network Manager
University of York
20 Jan
20 Jan
11:45 p.m.
New subject: [pups] 2.11BSD disklabel-programm
On 2002.01.20 15:57 Pete Turnbull wrote:
RX50,
I know. I once saw a MV II with a second RD54 in an external case. There
was a real mess of wiring to get it and the internal RD54 work together
on one RQDX3. Puting the TK50 out of the BA23 and mounting the second
RD54 in the BA23 would have been much simpler. But not the DEC way of
live. ;-)
Lothar later said this is an H9276-A. That's a
straight backplane,
all Q22/CD. It seems he has a BA11-S not a BA23 :-)
Aha. OK. That is a different
story.
BTW, DEC normally recommended all comms and network
cards go after the
memory, tapes next, then disks.
I usualy put comms after the CPU, then network,
tape (or tape, network,
what fits best for the wiring) and disks last.
It's the order of the boards (and the boot ROMs)
that make it 11/73 or
11/83, not the circuit board. Though original 11/73s are 15MHz and
original 11/83s are 18MHz.
[...]
That's a dual-height board, CPU only, with no
boot ROMs, LTC, or SLUs.
It was only sold as an OEM product or as an upgrade to 11/03 or 11/23
Ahhhhh! My
PDP 11 has this M8192 board with FPU but without ROMs...
I thought that this is the "original" 11/73 CPU. But on this PDP is
nothing "original". The BA23 was a MV II, the CPU was EPayed, the RAM
board was given to me by a friend. (Many PC/XTs had to donate there RAM
chips to fill it.) I found the console SLU at the scrap yard, the Dilog
ESDI controller was EPayd (in England BTW ;-) ) ... and I am still
looking for a ROM card... But I will get a /83 CPU card with ROMs in a
few months...
All my front
panels have only one disk write protect / online
switch.
The BA23 was only rated for one hard disk and either a TK50 or an the BA123 (which uses the same panels) was rated for
up to 4 MSCP
devices.
That's why the WP and ONLINE switches and LEDs are on a subassembly,
so you can add another one.
I know. My MV III lives in a BA123. (With 4 ESDI disks,
TK50 and
floppy.)
--
tschüß,
Jochen
Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/
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