PCT keyboard info

[mnementh@netcom.com (David R. Villegas)]

Up until recently I had been using my //e's keyboard when using my PC
Transporter but I ran into some troubles.  The PCT keyboard adapter interfered
with the game I/O.  With the adapter installed, pressing either button 0 or
button 1 caused the values of PDL(0) and PDL(1) to jump up slightly.  This
wasn't much of a hassle in games but was annoying in drawing programs.
Since my trackball was better for the latter, I left the setup alone.
But one day I used my Thunderscanner and it refused to work with the PCT
keyboard adapter installed.  I promptly disconnected the adapter but in IBM
mode, the shift key didn't work and the caps lock key wouldn't bring up the
PCT menu.  So I decided to attack an external IBM keyboard.  Here's some
info about using an external keyboard:

You need a cable to connect the PCT to an external keyboard.  The cable should
have a 5 pin flat cable connector on one end and a 5 pin DIN on the other end.

flat connector   A  1   DIN (female)
                 B  2
                 C  3
                 D  4
                 E  5

The connections are easy to remember.  I arbitrarily labelled the pins on
the flat connector A-E where A is the pin on the top of the card and E is
the pin on the bottom of the card.  The DIN pin assignments are

  4 2 5    1 CLK/CTS   4 GND
 1     3   2 RxD       5 +5V
    _      3 RESET

The cable depicted in the PCT manual and in the installation video wasn't
shielded.

The keyboard has to be XT-compatible.  Modern keyboards should have a switch
that toggles AT-compatible or XT-compatible but some only are AT-compatible.

-- 
David Villegas  (ENTP)                                     mnementh@netcom.com
San Francisco, CA                                   villegas@csli.stanford.edu