Repurposed old keyboard electronics as a large digital input sensor

Hi, I like to take things apart and begin to understand how things work. I'm pretty good at it when it comes to mechanical things. Electronics leaves me confused once things go from the logical to the physical. Digital logic I understand. It's when the digits hit the real world of wires etc. and the timing issues etc. that keeps me baffeled. Another one of my quirks is, how can I re-purpose stuff I've already got, especially if it's junk or has no future monetary value. I can then do things with it with impunity. To that end here is my question. Is there a Arduino shield that allows connection of an old PC keyboard? Can such a connection to an Arduino read the keystrokes as they are made? It would be nice to be able to re-purpose the keyboard electronics, without reporogramming the keyboard chip, to be able to send keystroke values to the Arduino board. The latest Uno USB interface is supposed to be able to be reconfigurable/reprogramable to read USB keyboards. But I'm talking about the old wired keyboards. There a typically 101 or more keys on such a keyboard and it would be great to be able to take the electronic guts of such a keyboard and turn it into a massive digial input array. Taking that to the next level, what about using old wireless keyboards along with it's receiver with it's USB cable. You get the idea. A whole lot of digital input signals, possibly wireless, that would give an Arduino more sonsors to experience the world around it. Hope this a new topic. If not, please refer me to where it's already been written up. Thanks, Norm

the stuff you want is a PS2 connection ( if keyboard is usb, grab a usb-ps2 adapter ) there are keyboard and mouse libraries for arduino, found them a while ago, search ps2 and arduino.

Try here for example:

Thank you guys. It's like having a world wide reasearch team at one's disposal. This is great. That takes care of the keyboard communicating key codes to the Arduino. Now I'd like to take the keyboard electronic guts and create a patch panel that replaces the switches under the keys with somethng a little more worldly, like switches and sensors. The intent is for the keyboard electronics to work just the same old way sending key codes to the Arduino but using a variety of (digital) sensors/switches. Since the keyboard electronics still sends keycodes, that chip effectively generates a byte (keycode) that has embedded source information (effectively which key was pressed) in the sequential data stream it sends. Of course it will have a very low rate of transmission compared to what is normal today. But for the purpose of signaling physical/mechanical things it would still be plenty fast enough. To do that what has been done to create such a patch panel and what electronic signal characteristics are requires. Things like duration of switch closure (equivalent to a keypress) at what voltage and current, things like that. I could measure some of these parameters, but I'm always leery of my own skils and that one last thing I did not account for that will bring Murphy out of retirement (Murphy has never retired!). I just opened up four old keyboards in the basement. Two had Z8 microcontrollers in them and the other two were Intel 8049 and 8032 (I think). These are all sort of Intel 8051 like devices. I know they used to work and I'm pretty sure the would still operate if the input side of these chips is reconfigured. I hope you'll be able to diret me to a URL showing that that's already been done long ago. Thanks again everyone. Norm