Compaq Portable Keyboard Pinout

[Macmaster2000]

I've got a Compaq Portable I with a bad keyboard. I have tried to fix it, but it seems to make more keys stop working, so I've decided to just try to attach a keyboard. Somewhere I read that it should be a standard connection, but its got a different plug, yet with the same number of pins.
Anyone have a way to figure out which pins are which? Ill post a pic below.

 

[SomeGuy]

As far as I can tell, no one has the Compaq Portable keyboard pinouts out there, and it is not known if the keyboard protocol is even IBM PC/XT compatible.

You should be able to use a volt meter to find the ground and +5 volts. Once you know those, nothing else should blow up if they are not connected right.

That would leave pins for: Data, Clock and Reset. Which leaves only a few possible combinations, but would be annoying if no combination worked.

 

[Macmaster2000]

That's what I was thinking, well, looks like I gotta go get a multimeter!

 

[compu_85]

There's a guy selling replacement foam pads on ebay, or you can make your own. Wrapping paper can be used to make new "contacts" (they don't conduct, the controller senses the capacitance change).

I just rebuilt my Lisa's keyboard, which uses this same Keytronic "Foam & Foil" switch. Do some searches, you'll find lots of people talking about it.

-J

 

[SpidersWeb]

Macmaster - for testing you'll most likely need a keyboard that supports the XT protocol laying about too.

There's a guy selling replacement foam pads on ebay

If anyone decides to sell these foam pads with the metallic surface already attached, TAKE MY MONEY.
Repetitive tasks drive me insane. I've got the pads, but can't bring myself to redo my Apricot keyboard.

 

[Macmaster2000]

There's a guy selling replacement foam pads on ebay, or you can make your own. Wrapping paper can be used to make new "contacts" (they don't conduct, the controller senses the capacitance change).

I just rebuilt my Lisa's keyboard, which uses this same Keytronic "Foam & Foil" switch. Do some searches, you'll find lots of people talking about it.

-J

I've been trying to make my own, and used tinfoil and command strips, but whenever I'd hit a key , like the number 1, it would type a random string of about 5 letters.

 

[compu_85]

That's because you can't use something that's conductive on the bottom. You want something that's metalized on the "back" and plastic on the surface that touches the contacts.

I use a hole punch to cut the mylar. I'll draw on the conductive side with a marker so I know which way to stick them on the foam pads.

This guide has great info: http://vintageapple.org/lisainfo/Lukes_LISA_keyboard_repair.pdf

-J