Evening friends,
A while back I obtained a United U-2200. Based on feedback from several members in earlier posts, the actual Uniteon keyboards are very rare. I know Apple II+ keyboards can be modified to work, but it pains me to tear apart an Apple II+ to scavenge it's keyboard.
That being said, I am looking for alternatives and would welcome any suggestions.
My thought is to take a 'claky' USB keyboard and convert it to work as the Uniteon's externally connected keyboard. I am just beginning this quest and the following comes to mind.
1) I suspect the exterior plug of the Unitron is like the 16 pin keyboard connector on an Apple II+ motherboard. From this, I suspect the Unitron is expecting the post encoder signals from an Apple II+ keyboard.
2) This makes me think the solution would be to use the solutions employed with Teensys to interface vintage keyboards as USB keyboards but in this case "reverse" the process and change the USB keyboards signals into post encoder signals for the Unitron.
****UPDATE*****
I decided to use a PS2 keyboard and this solution.......as a first attempt.
https://github.com/markadev/Appleii-Keyboard
Mark
Have you tried/tested the the PS/2 option with the Unitron U-2200? I have keyboards for my units but it would be interesting to try, especially since I have one of the U-2200's on the bench right now (was faulty but is repaired now (and working)).
There were many "external" type clone keyboards made in the 80s.
They come up for sale on eBay from time to time. I wager that any of them would work, provided they get plugged directly into the 16 pin socket on the motherboard.
I think that at least one model of external-keyboard Unitron clone had a funny keyboard connector on the case, so you'd have to bypass that.
It might be worth waiting for one of these keyboards to come up on eBay because adapting a standard genuine Apple II+ keyboard to you Ubnitron might work ok, btut it would be ugly and you'd lose the abilityo to type lower case characters.
Here's an example of a completed recent eBay auction for such a keyboard.
https://www.ebay.ca/itm/Vintage-Apple-II-II-Plus-IIe-IBM-Style-K100-DETACHABLE-KEYBOARD-/275062746857?_trksid=p2047675.m43663.l10137&nordt=true&rt=nc&orig_cvip=true
That keyboard is almost exactly like my Unitron keyboards (all mine are the same model). Goes directly to the 15-pin connector on the front of the U-2200.