Circuit to test keyboard encoder?

[groinksan]

I'm in the process of writing a keyboard encoder. The encoder will eventually be able to handle ghosting of up to four or five simultaneous keys. The encoder inputs will be the usual X/Y matrix, along with separate signals for things like the shift keys, control keys, and so on.

Right now, I don't have a physical board with key switches to test the keyboard encoder as development progresses. So, I was thinking about developing a circuit to send simulated keystrokes to the keyboard encoder. Then this way, I can pre-program a sequence of keystrokes, and then monitor the output to see if the encoder is correctly handling the repeat, ghosting and debouncing. My intent is to create such a circuit using something quick and handy like an Arduino, as I have a bunch of Arduino's and Teeny microcontrollers.

Before I go about creating this, are there any projects out there that does pretty much the same thing?