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Make your own BC18 cable

	Just a heads-up to those who may have tried to make their own VAXStation
II/GPX video/keyboard/mouse cable (the BC18 series), based on the
information at: written by Dave Clark (yes, I CC'd him on this).

	There are a couple of typos in the pinout cross-reference, as shown in the
FAQ, which caused me to have to re-pin both ends of my cable (and might,
under different conditions, have blown something out -- thank God that
didn't happen!) The pertinent corrections are shown below.

DB15:		KB RJ11:	Mouse:	Function:
15		1 				KB Transmit
6		2				KB Receive (Was shown as 7 on the DB15 side)
14		3				KB Ground
8		4				KB Power

5				2		Mouse TX
13				3		Mouse RX
7				1		Mouse Ground (Was shown as 6 on the DB15 side)
4				5		Mouse +5 VDC
12				4		Mouse -20 VDC

9						Red Video Hi
1						Red Return
10						Green/Sync Hi
2						Green/Sync Return
11						Blue Video Hi (Was shown as 1 on the DB15 side)
3						Blue Return

	In summary, the corrections I found necessary were: Pins 6 & 7 were
transposed on the DB15 side, and pin 11 (Blue video high) was incorrectly
labeled as pin 1. 

	I have assembled a 'cheater' cable for my VAXStation II since, for some
reason, my BC18 cable did not have a mouse connection, and have pinned it
to bring out the mouse connections on a separate cable leading to a 7-pin
Mini-DIN connector. So far, I've seen no indication that this does not work
(meaning that the mouse or support circuitry has not gone up in smoke yet),
but I have yet to install windowing software to test the mouse. I will post
the results here as soon as I do so.

	Caveat emptor!

From: Bruce Lane kyrrin at