By default, screen characters appear using simple ASCII key translations.
If desired, the application can set up alternate key mapping.  A pointer
to the keymap structure is placed into the altkeymap field of the
stringinfo structure.  the gact_altkeymap bit in the activation flags of
the gadget must also be set.

See the "console device" chapter in the amiga rom kernel reference manual:
Devices, and the "keymap library" chapter in this manual for more
information about the console device and key mapping.