Does anyone know of a way to get the Power Pad functions to work in fceumm or nestopia (if these functions exist)? Are there standalone (non-libretro) versions of these emulators available for the Pi 3B? I didn't see them in the various package lists in the RetroPie setup menu.
The standalone versions of fceumm or nestopia are not included in RetroPie. They seem to support the PowerPad input type, but that type of input is not explicitly exposed in the libretro port.