I have a PDP-11/34 programmer's console, what should I do with it?

From: Ethan Dicks <erd_6502_at_yahoo.com>
Date: Wed Mar 6 14:14:55 2002

--- Gunther Schadow <gunther_at_aurora.regenstrief.org> wrote:
> Hi,
> I have a PDP-11/34 programmer's console but no PDP-11/34, what
> should I do with it? My options are:
> 1) get a PDP-11/34

Always a nice choice if you can manage it.
> 2) trade it with something I need more, like a PDP-8/A power
> regulator(G8018) and limited function panel so that I can
> build my third PDP-8/A :-)

I don't have any spare regulators (I am, in fact, short one - missing
caps from the previous owner and no expectation that the board works),
but I do have a limited function panel sitting on the shelf - it has
the BERG connector, *not* the 16-pin-DIP connector; probably why it's
sitting there. None of my OMNIBUS boxes are wired to talk to it.

I do have a 5.25" 11/34 in my basement right now, with a limited-function
panel, but I'm not sure you can _put_ the programmer's panel on the
short 11/34s. We always used ODT on it anyway (cf. recent discussion
about force-feeding PDP-11s from a VAX via ODT and special console toggle
switch - this one _is_ that PDP-11).
> PDP-11s were never really my plan to collect, but I wouldn't
> mind having one specimen of 2.9 BSD running. So, may be I
> should get an 11/34?

The 11/34 should do for 2.9BSD. I haven't tried it there - memory tends
to be a little tight. I _have_ loaded 2.9BSD on a loaded 11/24, some
time ago, c. 1987, ISTR. I splurged on a KT24(?) from Terry Kennedy just
so I could have more RAM. I had the memory cards, but I couldn't address
them without it. I finally gave up on 2.9BSD on real -11 hardware when
I couldn't manage to locate a disk larger than an RL02 that 2.9BSD
supported (no MSCP). I didn't have any SMD disks available, and the only
real choice would have been an RK611 with a bank of RK07 drives. I still
haven't had any SMD or ESDI Unibus controllers cross my path in the past
15 years. All I have for Unibus disk is _still_ UDA50s and RL02s. I
could install and run the base packages on a dual 10MB system, but there
wasn't room for sources and to rebuild the kernel. 28MB would have done
it though, I think. 56MB would have been sweet (we used to use a dual-
RK07 configuration when we did compatibility testing with our product
and 4.0BSD, 4.1BSD and SYSV in 1984/1985 on an 11/750 w/2MB of RAM).

There's nothing intrinsically wrong with an 11/34, but they seem small to
me. I guess it's better than an 11/04, and there certainly were a lot
of 11/34s shipped, so they tend to be easier to find, in my experience,
than other Unibus PDP-11s. I guess when you look at the 18-bits of
address space on the Unibus, compared with 22-bits on anything Qbus
from the KDF11 on up, and with the other techiques used by larger Unibus
-11s, the 11/34 _is_ kinda small. 256K is plenty for RT-11, but it
gets a wee bit cramped, not for Unix itself, but for the way we are
accustomed to using Unix. There's room for the kernel (if it's optimized
for your hardware), but I don't recall wanting to try a second user
under 2.9BSD and 256K of RAM.


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Received on Wed Mar 06 2002 - 14:14:55 GMT

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