Questions regarding a PDP11/34a

From: Gooijen H <GOOI_at_oce.nl>
Date: Fri Jun 15 01:52:20 2001

Hello Sean.

Ok. I'm back.
Sorry for the silly question of which DL11 board you have.
You mentioned it in the board list. Anyway, here's how I
have connected the M7856 to a VT220 (EIA, RS-232C).

                             +------------------+
                             |.(B) ...... (VV).| |/
                             |.(A) ..... (UU).| |
=====================================================|\
                                                   ==
(viewing the edge of the M7856 where the BERG connected is)

The lower righthand side pin (closest to the board is A.
Right above it is pin B. At the lower lefthand side, the pin
closest to the board is UU, and above it is VV.
Then, the alphabet on the BERG connector is as follows.

   B D F J L N R T V X Z BB DD FF JJ LL NN RR TT VV
   A C E H K M P S U W Y AA CC EE HH KK MM PP SS UU

The following wires run from the BERG connector to the DB25
connector I have at home (forgot to write down if it is male
or female). Also, because I made it fit to a longer wire with
DB25's at both ends it *_might_* be a null-modem cable....

   BERG DB25
===================
    VV | 7
    DD | 20
     V | 4
     J | 2
     F | 3

Further, a small wire connects (E) to (M) on the BERG connector.

BTW. My 11/35 has an BM872. It is a boot card (dual) with diodes
on it to form a matrix addresslines/datalines. So, you can solder
your bootstrap program's zeroes and ones in real hardware :)

Success,

  Henk.
Received on Fri Jun 15 2001 - 01:52:20 BST