A button that does nothing, a stick that drifts, a pad that is recognised but unusable: before reconfiguring everything, test it. Recalbox 10.1 ships a visual tester, plus two command-line tools for the awkward cases.
START → CONTROLLER SETTINGS → TEST A CONTROLLER.
Pick the controller (hold one of its buttons for a second), then press its buttons one by one: each button you press lights up on the controller artwork. It is the quickest way to check a whole configuration, including stick axes and analog triggers.
The tester closes with HOTKEY + START.
If the controller does not respond at all, it is probably not configured yet: go through the controller configurator.
sdl2-jstest: see what the system receivesThe sdl2-jstest tool is installed on every Recalbox 10.1 image. It shows what SDL — the layer used by EmulationStation and by the emulators — actually sees of your controller. Connect over SSH to use it.
sdl2-jstest --list
Sample output:
Joystick Name: 'DragonRise Inc. Generic USB Joystick'
Joystick Path: '/dev/input/event0'
Joystick GUID: 030000001008000001e5000010010000
Joystick Number: 0
Number of Axes: 2
Number of Buttons: 10
Number of Hats: 0
Number of Balls: 0
GameController:
not a gamepad
The useful bits: the controller's exact name (quote it when asking for help), its number, and the axis and button counts.
sdl2-jstest -e 0
0 is the number obtained with --list. Press buttons and move the sticks: the events scroll past. This is how you find out the number of a button or an axis, which you need in order to write a configuration override or to customise a mapping.
EmulationStation holds on to the controllers. If no event shows up, stop the frontend for the duration of the test with
es stop, then bring it back withes start.
evtest: going down to kernel levelevtest, also installed by default, displays the raw Linux kernel events, before SDL. It is useful when a controller does not even appear in sdl2-jstest --list: it tells you whether the device is seen by the system at all (and under which name) but misclassified.
evtest
The tool lists the available input devices and asks which one to watch.
evtest but not in sdl2-jstest: the device is not declared as a joystick by its manufacturer. Report it on the Recalbox Discord with its exact name: Recalbox carries a list of exotic devices forced into joystick mode, and yours can be added to it.