Wyse Wy60 variants - output format?

[N8YX]

Hi all,

Newcomer and long-time tinkerer here...except in the black magic world of keyboards, where I'm an outright neophyte.

I'm trying to interface the following

http://www.universal-radio.com/catalog/hamhf/yr901.html

http://www.foxtango.org/ft-library/FT-Library/FT101ZD-901-902/YR-901.pdf

with a Wyse WY60 keyboard. That model is (ahem) supposed to work with the reader unit, and one such individual whom I contacted said that his just "...plugged right in...". (Neat trick, inserting a 4-pin RJ- modular into a 7-pin DIN!)

Thus far I've acquired and tried two - the 901867-01 and the 840338-01 - using pinout information I found on this site. No luck.

My main question: Is the keyboard scanner chip which Wyse uses in these a source or sink? Stated differently: Does it output a positive-going data stream when keys are pressed, or will it pull a load that's applied to the DATA line low?

If one looks at the schematic of the matching accessory keyboard

http://www.foxtango.org/ft-library/FT-Library/FT101ZD-901-902/YK-901.pdf

one sees that the connection to the reader unit is via a transistor, in an emitter follower scheme. This seems to indicate the reader expects a loop-driver arrangement (ASR33, anyone?) rather than a pulldown.

I have another ASCII keyboard which was built specifically for ham use (it sends 5-bit Baudot or 7-bit ASCII via a loop driver) and when I connect this to the reader I get characters registered on  the reader's monitor screen as I type. So...that much is working.

Anyone have more details on what the DATA line actually does? FWIW, I'm supplying 5v, CLOCK and GND to the WY60 boards as required through the reader's interface connector. If necessary, I can build a converter/driver - just need to know what's "normal" for one of these boards.

Insight here is most appreciated.

-Fred-

[ebacho]

Most of what you said went completely over my head, but there are a number of resources and threads on WYSE boards:

https://geekhack.org/index.php?topic=51079.0
http://www.kbdbabel.org/signaling/ (scroll down)

[N8YX]

Looking at some of the WY85 and similar timing diagrams (and hoping Soarer will chime in...) I see six 17uS clock pulses followed by another of between 34-140uS in duration. This sequence repeats.

How critical is that clock sequence when it comes to generating an ASCII word from the KB? Would just a steady stream of 17uS pulses suffice?

The reader unit I mentioned in the initial post has a 110 baud clock generator output. Its pulses are ~1.7mS, and no "stop" pulse of extended duration (verified by oscilloscope). I can possibly synthesize a clock sequence with my test lab's function generators and test the keyboard on the bench if required.

[Daniel Beardsmore]

Interesting. The keyboard that goes with this (YK-901 ASCII Keyboard) is identical to the Alps AKB-3420 ASCII keyboard, for which we have the specifications.

[N8YX]

Now if only I can lay my hands on a -3420! 

Still wondering what's required to bench-test the WY60s I have on-hand. That reader I linked doesn't output the "6 short-1 long" Wyse clock sequence which has been described in threads elsewhere on the site. It's a series of short pulses at a 110 baud rate.