sys_attrs_gpc_input - gpc_input subsystem attributes
This reference page lists and describes attributes for the GPC Input
(gpc_input) kernel subsystem. This subsystem handles mouse and keyboard
input for both old style LK* keyboards and serial mice, and the newer PC-
style (PS/2) keyboards and mice. In all supported scan codesets, unique
single-byte scan codes differentiate the standalone Insert, Home, Page Up,
Page Down, Delete, and End keys from the same keys on the numeric keypad
(with Num Lock toggled to off).
Refer to the sys_attrs(5) reference page for an introduction to the topic
of kernel subsystem attributes.
The gpc subsystem has a number of visible attributes. Of these, only the
following should ever be modified:
A value that identifies the scan codeset generated by the keyboard.
Only two values are supported for this attribute. The scan codesets
that these values identify differ in how internal keyboard hardware
distinguishes between the numeric keypad's Up Arrow (entered with with
Num Lock toggled off) and the standalone Up Arrow key.
Keyboard hardware sends different single-byte scan codes to
distinguish the standalone Up Arrow and the Up Arrow entered
through the numeric keyboard (with Num Lock toggled off).
2 Keyboard hardware sends two bytes for the standalone Up Arrow
and a single-byte scan code for the Up Arrow entered through
the numeric keyboard.
These values are intended to be set by system software, not users.
Although both values (scan codesets) work with most of the Compaq key-
boards (both LK* and PC-style) used with Tru64 UNIX systems, 3 identi-
fies the scan codeset that is most efficient for these keyboards. The
keyboard of the AlphaBook (laptop) computer is the only supported key-
board that requires the 2 setting. The scan codesets identified by
these values may work with other (third-party) keyboards; however, Com-
paq does not test or support other keyboards for use with Tru64 UNIX
It is possible to set kbd_scancode to a 0 or 1 value. These values are
currently undefined and will result in one of the following console
gpc_input_configure: scan code not supported
ps2_input_configure: scan code not supported
These errors are displayed independently of the setting for the
Enables (1) or disables (0) boot- and run-time console messages used by
systems programmers to debug device driver configuration problems.
Default value: 0 (disabled)