Looking for an answer I came across [this question][1]. There's something like this:

> The keycode X uses and the keycode the kernel uses are OFF BY 8 for "historical reasons". So take 97 - 8 = 89 and use 89 with the setkeycodes command (again as root):

Does anyone know what the historical reasons are and why the codes differ by 8?


 [1]: http://unix.stackexchange.com/questions/49650/how-to-get-keycodes-for-xmodmap