I think joystick button and axis mapping needs to be done
at the operating system level And in each application
(Hatari or? SDL) because each app may need different
mappings. Note that jscal -u is not user-friendly because
you must modify the cryptic output of jscal -q
Linux Devuan chimaera operating system example:
**** joystick calibrating and remapping buttons as superuser
jscal -c /dev/input/js0
jscal-store /dev/input/js0
jscal -q /dev/input/js0
jscal -u 6,0,1,2,5,16,17,12,294,289,290,291,292,293,288,295,296,297,298,299 /dev/input/js0
jscal-store /dev/input/js0