Post count: 480

With the pad plugged in type: ls /dev/input/ (this list the assigned device numbers of joysticks/gamepads)

Note the number after js

Here is my retroarch.cfg setup for a 360 pad:

You need to edit it and change input_player1_joypad_index = to the number noted above.

Place it in /opt/retropie/configs/all/

To test buttons and make adjustments:

sudo apt-get install joystick

jstest /dev/input/js* (replace * with js number as above)