There are a couple of 56K-xxx AT&T keyboards there, but I counted, and there are only
6 wires in the female connector. There is not a fixed cable.
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at
classiccmp.org] On Behalf Of Ethan Dicks
Sent: Thursday, August 11, 2016 8:25 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Atlanta Open House Tomorrow
On Wed, Aug 10, 2016 at 8:15 PM, Al Kossow <aek at bitsavers.org> wrote:
If anyone goes there would you PLEASE look for a Qume
201 and
Televideo 965 keyboard for me
Likewise, I'm looking for a couple of AT&T/Teletype keyboards for my 5620/Blit and
my 730+. They do _not_ have a round DIN plug, which distinguishes them from 98% of
what's out there. They have an 8p8c connector ("RJ-45").
There are several matching keyboards with different numbers of keys (~98-103).
56K-341-AAN is one part number. Keyboards that will work are the same ones used on the
AT&T 4410 and Teletype 5410 terminal.
I'm also seeing part numbers in the technical drawings
(
http://www.brouhaha.com/~eric/retrocomputing/att/5620/att5620_eng.pdf
pp 87-95) like:
56K224
56K229
56K230
410896
410967
It appears to have 6 of the 8 pins in use - serial in, serial out,
+5V, -12V, signal GND, and frame GND (it makes its own -5V for the MCU
from a zener diode on the -12V line). All of this plus
the 1.8432MHz crystal, suggest to me a simple async protocol. This would make a keyboard
emulator simple to construct once someone has sniffed the protocol.
One is good. Two is better.
Thanks,
-ethan