HP 2116 on ebay

[Brent Hilpert]

Jay West wrote:
> The only thing amiss to me is Brent said there were two GND TRU boards, but
> I only see one listed in the auction. You would have to have two for sure as
> the IPCK was always four 12566 boards with 2 on each end. One pair used for
> sending and one pair used for receiving.

This is one of the discrepancies between the seller's card list and the
picture. Looking at the (large) card cage picture one can observe that the
3rd and 4th boards from the left on the I/O level are (visibly) identical.
Eliminating other cards in the seller's list, and a little deduction suggests
they would both be GND-TRUE IN/OUT boards.

Conseqeuently, I believe this is a more accurate list for the I/O level:

A201
CENTRAL INTERR.
GND-TRUE IN/OUT
GND-TRUE IN/OUT
TIME BASE GEN
MUX a \
MUX b | 1st mux set
MUX c /
MUX a \
MUX b | 2nd mux set
MUX c /
-
-
-
...

> > and the amount of memory which would be implied by the remaining memory
> > module cards.
> I would wager that 2000/Access makes the most demands of the IOP due to the
> IBM/CDC MRJE stuff, and it's requirements for memory in the IOP are anywhere
> from 16kw to 32kw depending on software options selected at IOP generation
> time. I would think that the prior versions of TSB would certainly not need
> more than Access so I'd have to suspect the memory indicated by the non-SSA
> cards in the memory subsystem is adequate.

Sorry, I left out a phrase, I thought 16-24 KWords would be excessive
for the task. I can understand the separate IOP to offload all the work of
multiplexed bit-banging for 16-32 ports, but I didn't think the code and
buffer size requirements in the IOP would be very great.
(With RJE stuff in there, there's more going on than I was aware of.)