Unicomp Model M USB conversion?

[wmcbrine]

Hello all,

I have a PS/2 Model M keyboard from Unicomp, dated August 2004. My last PS/2 motherboard died last year, so I've been using it with a USB adapter. But when I use it this way, I get a lot of spurious keystrokes, and sometimes the lights will flash, and all input will be ignored for a few seconds. And rather than go through however many adapters it takes to find a better one, I thought, why not convert the keyboard itself?

I've read about the mods that involved incorporating a PS/2-to-USB adapter into the keyboard case (which I don't want), and I've read about the mods that involve a new controller board built with an ATmega, which I'm not ruling out. But I wondered, might there not be some existing controller that I could just swap in? Certainly Unicomp must have them... And then I thought, 2004 is well into the USB era; what if the controller board that's already in there can do USB, with a few mods? What made me wonder was seeing this:



It's got jumpers, an empty socket, and more. Am I crazy?

I know I could get a new Unicomp keyboard, but I value this one because it has black keycaps, which they don't make anymore. And I guess I could get one just to swap the controllers, but that seems like overkill, and a waste. Any advice?

[E TwentyNine]

Unicomp doesn't sell a USB version of that controller board.   The newer unicomp keyboards use a smaller controller above the numpad.  Don't know that they ever had that form factor with USB.

If you don't want an external converter (the bluecube one is used often and I've never had a problem with it over multiple computers for years), your best bet is a converter (not a controller replacement) using something like Soarer's code.  Cost about $20 and some time to solder/connect 4 wires. 

All that said, got some pictures of the keyboard?  The white on black non trackpoint boards are very rare.

[bcg]

ESR has taken the time to document reports of issues with Unicomp's USB controller:

http://www.catb.org/esr/faqs/model-m-troubleshooting.html#_usb_unicomp_issues

So even if you found a controller from Unicomp that would work it seems like it might still have the same issues that you are experiencing.  What kind of PS/2 adapter are you using?  Is it an active adapter or a passive one?  I know many people report problems with the cheap passive ones.

I've never had an problems with the blue cube but its really boring.  Soarer's converter has always worked great for me as well, and with that you're able to remap keys to your liking as well

[wmcbrine]

Thanks for the replies. I've decided to try a bluecube for now.



(That's the right one, yes?) So far so good, but it's early yet...

All that said, got some pictures of the keyboard?  The white on black non trackpoint boards are very rare.

Sure thing -- these pictures are in reverse chronological order:


Post-cleaning. (Half of my reason for getting the special tool and opening the case was to clean it out properly for the first time.)


The back.


Caseless.


Keyless.


Detail of key. I've used this keyboard pretty hard for the better part of a decade, and there's essentially no visible wear.

What kind of PS/2 adapter are you using?

This is what I'd been using:




I looked up "Ez-Pu21", and found these remarks:

"Instead of Adesso ADP-PU21, I got shipped EZ-PU21 which looks like the Adesso cable, minus brand name packaging. Even down to the label markings on the cable, it looks like Adesso. But the cable is glitchy. Rebooting constantly because signal is too weak to make it through the KVM.

Now I could say my problems are going through adapters to a PS2 KVM, but if that was the case, why does the Staples cable work? Why does this EZ-PU21 with googled reviews dated between 2003-2008 not work? And why, when I'm buying an Adesso ADP-PU21 and I even struggling with an EZ-PU21???

Googling EZ-PU21, its made by AVS or some other company. Newegg reviewers all say they have the same problem with EZ-PU21 on KVM. Doens't work."

So perhaps this is truly is a poor-quality adapter? I dunno.

[E TwentyNine]

Don't know about the quality of that adapter.   I've had bargain basement cheapo adapters work fine depending on the computer it was plugged into.

The Bluecube has always worked.  It doesn't let some of the normally unused scancodes through that the cheap one does, but that's only an issue if you're attempting to do something strange (like a bolt mod layout change where the unused key locations on the numbpad are used).

Another one people like is this here: http://www.idinnovations.com/usb%20adaptors.html