PS/2 Controller Keyboard

I wanted to ask if anyone can help me use the keyboard with NIOS?

Currently I know that there are some C functions that can help me with this but I'm still not sure how the keyboard works.

Say I want the to hold the up arrow and have a LEGO motor turn on as long as the key is held down, what is the process for this to work? Do I need interrupts? or can it be done without it? etc

Any tutorials will be greatly appreciated. Until then, I will continue researching

Thank you