Press the unknown key and type 'dmesg' to console to see what kernel says.
For me it says:
atkbd.c: Unknown key pressed (translated set 2, code 0xbb on isa0060/serio0).
atkbd.c: Use 'setkeycodes e03b <keycode>' to make it known.
atkbd.c: Unknown key released (translated set 2, code 0xbb on isa0060/serio0).
atkbd.c: Use 'setkeycodes e03b <keycode>' to make it known.
So at least kernel recognizes them. The next step is to find free keycode:
dumpkeys |egrep '=$'
Select your favourite keycode from the list and assign it to the key. I did:
sudo setkeycodes e03b 120
Then use xev to see what X event the key creates. For me it gives:
KeyPress event, serial 31, synthetic NO, window 0x2a00001,
root 0x5c, subw 0x0, time 88366743, (165,-317), root
168,277),
state 0x10,
keycode 139 (keysym 0x0, NoSymbol), same_screen YES,
XLookupString gives 0 bytes:
XmbLookupString gives 0 bytes:
XFilterEvent returns: False
From there I read 'keycode 139', so I can assign eg:
xmodmap -e "keycode 139 = XF86Calculator"
Now my key gives XF86Calculator event, which I can bind to whatever I like with khotkeys.
If you ask me, all this should be done automatically; after all, kernel recognized the 'unknown' key and the rest could be automated. There could be a 'hotkey detect'-mode in which the system would find these unmapped keys and asked user to assign a X event for it.
