The default X server configuration varies from distribution to
distribution and release to release of GNU/Linux. If your system
fails to recognize the keypad keys as distinct keys, change the
NumLock state, turning it on or off, as the case may be, then try
again. If this doesn't solve your problem, you may have to modify
the X keysym mappings with xmodmap.
On one distribution on an Intel PC, the following .xmodmaprc set things up nicely.
! File: .xmodmaprc
!
! Set up PC keypad under GNU/Linux for the GNU Emacs EDT Emulation
!
clear mod2
keycode 77 = F12
keycode 96 = Num_Lock Pointer_EnableKeys
add mod2 = Num_Lock
In this example, after feeding the file to the
xmodmap command, the PC <NumLock> keypad key
will be configurable for the emulation of the <PF1> key.
The PC keypad can now emulate an LK-201 keypad (less the comma
key), the standard keyboard supplied with DEC terminals VT-200
and above. This .xmodmaprc
file switches the role of the <F12> and <NumLock>
keys. It has been tested on RedHat GNU/Linux 5.2. Other versions
of GNU/Linux may require different keycodes. (Unix for further help on how to do
this.)
Please note: Remember, it may be necessary to have <NumLock> in one position (ON) or the other (OFF) for the PC keypad to emulate the LK-201 keypad properly.