This tutorial explains Linux “setkeycodes” command, options and its usage with examples.
The setkeycodes command reads its arguments two at a time, each pair of arguments consisting of a scancode (given in hexadecimal) and a keycode (given in decimal). For each such pair, it tells the kernel keyboard driver to map the specified scancode to the specified keycode.
This command is useful only for people with slightly unusual keyboards, that have a few keys which produce scancodes that the kernel does not recognize.
setkeycodes scancode keycode
The usual PC keyboard produces a series of scancodes for each key press and key release. (Scancodes are shown by showkey -s command.) The kernel parses this stream of scancodes, and converts it to a stream of keycodes (key press/release events). (Keycodes are shown by showkey.) Apart from a few scancodes with special meaning, and apart from the sequence produced by the Pause key, and apart from shiftstate related scancodes, and apart from the key up/down bit, the stream of scancodes consists of unescaped scancodes xx (7 bits) and escaped scancodes e0 xx (8+7 bits). It is hardwired in the current kernel that in the range 1-88 (0x01-0x58) keycode equals scancode. For the remaining scancodes (0x59-0x7f) or scancode pairs (0xe0 0x00 – 0xe0 0x7f) a corresponding keycode can be assigned (in the range 1-127).
If you have a Macro key that produces e0 6f according to showkey, the command
# setkeycodes e06f 112
will assign the keycode 112 to it, and then loadkeys can be used to define the function of this key.
Sanfoundry Global Education & Learning Series – 1000 Linux Tutorials.