Dual modding a.... keyboard!?


A friend of mine came up with an idea which involves making a keyboard compatible with gaming consoles. I’m not talking about making a keyboard work in text messages or in chats, but being able to use the keyboard as a controller.

So, I bought the cheapest keyboard I can find from Fry’s and opened it up to see how the PCB works. The moment I looked at the PCB, I immediately noticed the first roadblock. The PCB only has 26 signals. I then tried to understand how the keyboard works by looking at the film, and noticed that there were two layers of film. Multiple signals are triggered when one key is pressed so the the controller knows which key to output. I did a little research online and realized that key repeating is also handled by the controller.

My question is, has anyone ever done this sort of thing? I was originally thinking of using a DB25 + PS2 Project Box to get it working. Even if I did that, the controller on the keyboard wouldn’t let me hold a keypress since it triggers a repeat. I know this is a silly idea, but I’m doing this for fun with a $3 keyboard.

You might be able to do it with an IBM model M keyboard since I think they still use switches if I’m not mistaken. Here’s a guide that PCWorld did on taking it apart. http://www.pcworld.com/article/147939-11/inside_the_worlds_greatest_keyboard.html

I did a project in which I did the opposite. I used the keyboard controller as a PCB for a SNES controller. It didn’t work out that well. It didn’t like me pressing more than 2 keys at once, which became an issue. Going the other way I’m guessing you’d have to use a custom IC to interpolate keystrokes, probably a royal pain.

Tetsuo is probably right, although there are other options in terms of older keyboards that use switches. The M is simply an all around great keyboard with excellent switches, but this also makes it a hot commodity and they probably run a little more pricey.

If you’ve got a used/junk computer shop locally try taking a look at their wares.