/diy/ - Do It Yourself

>>1391866
your game controller will need to use USB HID to emulate keyboard/mouse unless you want to write your own drivers. evidently arduino has an HID library available, but it's not something you can use through the normal ide since i assume you need to program the programmer too. i haven't ever touched this, and i have minimal experience coding for usb, but i can say this won't be entry level on the software side.
http://mitchtech.net/arduino-usb-hid-keyboard/

you shouldn't really need a matrix since you have so few inputs on a controller. you can most likely just use a perfboard, cut it to shape, and shove it in a printed case. designing your own pcb is fun though.