Keyboard Matrix Translation

4 posts / 0 new
Last post
Eudimorphodon's picture
Offline
Last seen: 3 weeks 5 days ago
Joined: Dec 21 2003 - 14:14
Posts: 1207
Keyboard Matrix Translation

At the moment this is still mostly a hypothetical question, but... has anyone here done a completely "stealth" computer recasing, similar to the VIA->Commodore 64/SX hack:

http://mini-itx.com/projects/sx64/

on mini-itx.com, and kept detailed notes on how they they did it? My particular area of interest involves keyboards.

I know there are a few options. The simplest is to just scrap a more modern PS2/USB keyboard for the controller and remap the matrix connections. The issue that I'm facing with that is the fact that the keyboard in question has many fewer keys then a normal PC keyboard, and it'll be annoying to lose the ability to generate missing keystrokes. (A possible solution to this would be to use something like a "Happy Hacking" mini-keyboard for the controller doner, as its controller is designed to allow you to replace the missing keys with arcane keystrokes, but they're sort of pricy to cut up.) Another solution is to make my own keyboard controller, like the SX/64 hacker did, but I suspect that doing so is somewhat outside my realm of expertise.

(The website for the C64 hacker has gone away, replaced by a mindless personal interest site, so copying his isn't really an option even if I could muddle through it. Archive.org's last scrape shows a promise to release firmware details, but it never happened. I wonder if he sold the design work to this german firm:

http://www.vesalia.de/e_keyrah.htm

Which makes (will be making) a prefab version. Unfortunately it's not a Commodore I want to stealth.)

Anyway. Anyone have experience/links? Completely stealth case conversions seem to be rather rare. Or, at least, I'm having trouble googling for them.

--Peace

ex-parrot's picture
Offline
Last seen: 6 months 3 weeks ago
Joined: Dec 20 2003 - 01:35
Posts: 6846
An idea I've toyed with is to

An idea I've toyed with is to use a PICAXE controller. They're very cheap and the higher end ones have a built in AT keyboard interface... I'm yet to actually try this though as I'm still not quite sure how the Osborne I want to replace the keyboard on scans for keypresses... I'm guessing if I just pull the right row/column low and high respectively it'll work, but I'm not sure.

Eudimorphodon's picture
Offline
Last seen: 3 weeks 5 days ago
Joined: Dec 21 2003 - 14:14
Posts: 1207
Re: An idea I've toyed with is to

An idea I've toyed with is to use a PICAXE controller. They're very cheap and the higher end ones have a built in AT keyboard interface... I'm yet to actually try this though as I'm still not quite sure how the Osborne I want to replace the keyboard on scans for keypresses... I'm guessing if I just pull the right row/column low and high respectively it'll work, but I'm not sure.

I'm guessing you have an Osborne with a missing keyboard? I'm pretty sure the keyboard "interface" for those was just row-column scanning, thus your idea should work. I used to have a couple Osborne Is, a working one and a dead one, along with some documentation, and if I recall correctly the keyboard scanning might of even been done in software similar to a TRS-80, with no dedicated ASCII encoder on the motherboard. The keyboard itself was definately "dumb", with not a single chip on it.

(Assuming you really wanted an Osborne if I still had them I'd give them to you for the price of shipping. I think they've probably been thrown out in the process of changing out-of-state storage units, though.)

Of course, I'm looking to do the opposite, which is find a suitable controller for using a "classic" (An Apple IIe, to be specific) keyboard on a modern machine via either PS/2 or USB. (If I can get it to PS/2 I can always use a PS/2->USB dongle for the last mile.)

I was counting keys on the "Happy Hacker" keyboard and thinking that would be the easy way out, but gadzooks they're just so darn *expensive*. $130 for the "real" one, and $70 for the "lite" model. That seems steep considering every other piece of this hypothetical hack would be scrounged.

--Peace

ex-parrot's picture
Offline
Last seen: 6 months 3 weeks ago
Joined: Dec 20 2003 - 01:35
Posts: 6846
Re: An idea I've toyed with is to


I'm guessing you have an Osborne with a missing keyboard? I'm pretty sure the keyboard "interface" for those was just row-column scanning, thus your idea should work.

Aye, that's correct. I've got a replacement keyboard I hand built, but it's not terribly well wired and many of the keys don't work Smile


Of course, I'm looking to do the opposite, which is find a suitable controller for using a "classic" (An Apple IIe, to be specific) keyboard on a modern machine via either PS/2 or USB. (If I can get it to PS/2 I can always use a PS/2->USB dongle for the last mile.)

Derrr.... I managed to completely misread your post. Nevermind Smile

Log in or register to post comments