DEC Professional/Rainbow/Decmate cable
(From Tony Duell)

  1 >----------+---------+-- Blue Gnd
     9 >-------O---------O-- Blue
  2 >----------+---------+-- Green Gnd
    10 >-------O---------O-- Green
  3 >----------+---------+-- Red Gnd
    11 >-------O---------O-- Red
  4 >----------+---------+-- Mono Gnd
    12 >-------O---------O-- Mono
  5 >----+
    13 >-+     +------------ Power Gnd
  6 >----------+------------ Key Gnd
    14 >-------------------- From Key
  7 >----------------------- Power 12V
    15 >-------------------- To Key
  8 >----------------------- Key 12V

   LK201 keyboard (RJ11-- front face view)

                -------
                |     |
          -----        -----
          |                |
          |                |
          |                |
           --  ^  ^  ^  ^--
               |  |  |  | 
 From Key -----+  |  |  +----- To Key
 Key 12V----------+  +-------- Key Gnd

---------------------------------------

DEC VAXstation 15-pin Dsub
(from BSDfans.org)

 1 - RED output (Color FB only)
 2 - COLOR_GND (Color FB only)
 3 - MONO_GND
 4 - +5V DC
 5 - MOUSE_RX
 6 - KBD_GND
 7 - GND
 8 - +12V DC
 9 - MONO output (Video signal + /VSYNC + /HSYNC)
10 - GREEN output (Green signal + /VSYNC + /HSYNC) (Color FB only)
11 - BLUE output (Color FB only)
12 - -12V DC
13 - MOUSE_TX
14 - KBD_RX
15 - KBD_TX

keyboard:
-----------
I         I  1 - Serial output
I 1 2 3 4 I  2 - GND
I         I  3 - VCC (+12 V)
I         I  4 - Serial input
---I   I---
   -----

mouse:
 /---#---\
/  5 6 7  \
I 3 --- 4 I
\   1 2   /
 \#-----#/

(This should look like a 7-pin mini-din connector)

1 - Serial input
2 - GND
3 - VDD -12V
4 - Serial output
5 - not connected
6 - VCC +12V
7 - VCC +5V