Some of you who know me well enough by now will almost expect a keyboard related post at some point in the ebb and flow of my Retrochallenge entries.

This competition will be no exception! Like all good entries it involves quite a journey!
I am an avid reader of Deskthority Mechanical Keyboards website and whilst browsing the marketplace noticed a member selling two keyboards, both brand new and clones of DEC keyboards. One using plate-mounted vintage cherry black modules, one using Hi-Tek ‘space invader’ key switches.

All Good Things…

The seller hurt his ankle just before posting so I waited about a month for the keyboards to arrive. When they eventually came one looked like a DEC-compatible keyboard (with modem-style connector) and the other clearly wasn’t DEC protocol – it was a tectronix terminal keyboard. One to look at another day.

Burning
I plugged the DEC compatible keyboard into my linux laptop that uses the lkkbd.c module to talk to DEC old-style interface keyboards via a RS/232 converter. It didn’t work but sometimes you need to reboot the laptop. I did this, still to no avail. However, when I unplugged the keyboard I noticed the cable was warm – that’s not a good sign! Then I noticed the unmistakable smell of burnt silicon.

Having opened up the keyboard I noticed my mistake. It was a wyse-compatible keyboard. The controller chip was really smelly and a diode had obviously been fried! So that’s a brand new keyboard from 1991 toasted. In about 10 minutes. Must be some kind of record even for me.

Phoenix from the flames

Not one to give up I found I had two options: find a replacement controller chip, replace torched components and then use Soarer’s Wyse keyboard converter running on Arduino Teensy to connect it to USB or completely replace the keyboard controller chip with a Arduino – a more involved solution.

The jungle drums went out for a replacement controller chip and after a week or so a very nice man from Belgium sent me one free of charge. I un-soldered the old one and replaced it, together with a couple of diodes. One flashed Arduino pro micro later and I had the keyboard responding! It could have been a quick hack from there but I really like the idea of using the existing keyboard cable, so I did some demon soldering, shink wrapping and the like to end up with the original cable ending in a USB plug.

Arduino Pro Micro running Soarer’s Wyse to USB converter

Transtec Wyse protocol keyboard with plate mounted vintage cherry mx black keyswitches – now USB compatible

Just typed this article on it and it is a sweet, sweet keyboard. Definitely in the top two I own – and that is saying a lot.

Epilogue

A note about Soarer’s converter software – it is fully programmable. He also does a PS/2 -> USB converter that is a million times better than off-the-shelf ones and, again, is fully programmable. This version of the software also supports XT -> USB and IBM terminal keyboard protocols.