25 Jul
2013
25 Jul
'13
9:23 a.m.
On Jul 24, 2013, at 6:55 PM, Roe Peterson <roe at liveblockauctions.com> wrote:
I'm looking to equip my unibus pdp11/34a and qbus
11/83 with Ethernet cards. I have no experience with old DEC network hardware, and I need
advice.
On the qbus side, what is the difference between a DELNA and DEQNA? Is one superior?
Is there a better alternative?
Do you mean DELQA instead of DELNA? The DELQA was the later Qbus Ethernet
board that I'm aware of. It's what I have; it has a 10 MHz 68000 on board,
which should be plenty for handling heavy Ethernet load. The older DEQNA
(which, if I'm not mistaken, is essentially a Qbus version of the DEUNA)
has power consumption/heat dissipation issues and some lockup issues as
mentioned before. The DELQA is generally backwards-compatible with the
DEQNA for most software, though it has a jumper setting which purports to
make it 100% backwards-compatible for less tolerant software (all DEC OSes
supposedly support DELQA in its normal backwards-compatible mode).
DELQAs usually aren't that hard to find on eBay, and if you're lucky, they
come with a cab kit (which isn't that hard to make, since it's a pretty
straightforward AUI cable with a fuse). DEQNA cab kits should work fine
with a DELQA.
As far as I can tell, the DELUA is the Unibus equivalent to the DELQA. In
general, if you swap a U for a Q in the name, that's what you're looking
for (which is why if there's something called a DELNA, I don't know what
it is, but the only picture purporting to be on I can see on Google looks
an awful lot like a DELQA to me).
As for unibus, any advice at all would be great. If
it matters, my 11/34a has both cache and floating point, 128kw memory, but I don't
know if there are any operating systems with tcp/ip that will run on it.
As mentioned above, AFAIK, Unibus has DEUNA and DELUA, of which the latter
is the preferred model. No idea how hard it is to come across that. For
TCP/IP, I know Johnny Bilquist has a stack for RSX-11M+, but that won't
run on 128kW of RAM. TCP/IP is a bit of a tall order for a PDP-11, but
DECNET isn't, and Linux still works more or less fine with it.
Speaking of: can anyone guide me as to how I should go about installing
DECNET on RSX-11M (not plus) 4.6? I'm having a hard time figuring out
which (if any) of the available images online will work for that version.
The tape images seem a bit hard to come by, and I've periodically scoured
Google looking for anything. Part of the problem is that I'm not as
familiar with the DECNET versioning system relative to the RSX one, so I
don't know what's compatible with what.
- Dave