Kaypro 2 keyboard issue

5 posts / 0 new
Last post
Stargeezer's picture
Offline
Last seen: 3 hours 13 min ago
Joined: Aug 4 2020 - 12:06
Posts: 148
Kaypro 2 keyboard issue

Hi Friends:

So a few months back I added a Kaypro 2 to the collection.  The machine did not have any software, but I found a ton online. Thanks to the help of fellow Applefritter member Bill Steube I now have disks.

But alas, I have run into a keyboard problem.  The machine boots fine, but at the a prompt, the computer puts 2 characters on the screen then gets stuck on '/' and just repeats.

I have checked the basics, actual stuck key, something creating a contact, checked the keyboard cable for continuity and connections.

The Kaypro is completely new to me so I hit the internet looking for possible solutions. Didn't find anyone with the same problem but a lot of info on the keyboard, schematics, etc.

Does anyone have experience with this computer? Perhaps experienced the same problem, or could recommend possible diagnostic steps to consider. Any thoughts or wisdom is greatly appreciated.

cheers,

mark

Online
Last seen: 9 min 27 sec ago
Joined: Feb 27 2021 - 18:59
Posts: 613
Keytronic

These keyboards used "foam-and-foil" switches from Keytronic and will need to be refurbished in order to work. The foam switches were not expected to last 30 years and are now kaput.

Offline
Last seen: 2 months 1 week ago
Joined: Jul 5 2018 - 09:44
Posts: 2587
Those foam and foil pads are

Those foam and foil pads are available from a few places.  They're kind of a pain in the @$$ to replace but it can be done.  Franklin also used this type of keyboard in the ACE 1000 and 1200.  Most of those keyboards need to be rebuilt.

 

Stargeezer's picture
Offline
Last seen: 3 hours 13 min ago
Joined: Aug 4 2020 - 12:06
Posts: 148
I don’t think it’s the foam and foil

Hi guys,

Thanks for the info on the pads.  Unfortunately I don't think that is the issue,  I disassembled the keyboard down to the PCB, hooked that up......exact same error. I made sure nothing was shorting the pads for the '/' key that would emulate a key press.  My gut says this is something logic related or otherwise. The caps lock light stays on too, which is odd. So perhaps something is generating the same signal of a key press.

I thing in need to dig into the schematic and check some logic levels. If it isn't in the keyboard IO pin of the SIO, it might be something else shorted on the keyboard circuit board that is creating the signal of the '/' being pressed.

mark

Stargeezer's picture
Offline
Last seen: 3 hours 13 min ago
Joined: Aug 4 2020 - 12:06
Posts: 148
A bit more information

So I did more digging. I learned you can connect a Kaypro keyboard to a modem computer with an FTDI interface and have it type out in a termiinal emulator, like Hyperterm or Putty.

I tried that tonight. I started with just applying 5v and ground.  The keyboard did the continuous beeping it does when connected. From this I am assuming the keyboard is the issue. Mark 

Log in or register to post comments