I can easily run 2600 games under Stella with just a SNES gamepad under RetroPie, but not having much luck running Atari 8-bit computer games using the same gamepad. I would need to map the Option (F2), Select (f3), Start (F4), Cold Reset (Shift F5) and Exit Emulator (F9) to gamepad buttons. This would allow me to run Atari 8-bit games without a keyboard. There are enough unused buttons on the gamepad for these functions. Any ideas?