evdev-joystick
Section: User Commands (1)
Updated: Apr 19, 2016
Page Index
NAME
evdev-joystick - joystick calibration program
SYNOPSIS
evdev-joystick --help
evdev-joystick --listdevs
evdev-joystick --showcal <
device-path>
evdev-joystick --evdev device-path>
[
--axis
<
axis>]
[
--minimum
<
value>]
[
--maximum
<
value>]
[
--deadzone
<
value>]
[
--fuzz
<
value>]
DESCRIPTION
evdev-joystick
calibrates joysticks.
Calibrating a joystick ensures the positions on the various axes are
correctly interpreted.
OPTIONS
- --h, --help
-
Print out a summary of available options.
- --l, --listdevs
-
List all joystick devices found.
- --s, --showcal <device-path>
-
Show the current calibration for the specified device.
- --e, --evdev <device-path>
-
Specify the joystick device to modify.
- --a, --axis <axis>
-
Specify the axis to modify (by default, all axes are
calibrated).
- --m, --minimum <value>
-
Change the minimum for the current joystick.
- --M, --maximum <value>
-
Change the maximum for the current joystick.
- --d, --deadzone <value>
-
Change the deadzone for the current joystick.
- --f, --fuzz <value>
-
Change the fuzz for the current joystick.
CALIBRATION
Using the Linux input system, joysticks are expected to produce values
between -32767 and 32767 for axes, with 0 meaning the joystick is
centred.
Thus, full-left should produce -32767 on the X axis, full-right
32767 on the X axis, full-forward -32767 on the Y axis, and so on.
Many joysticks and gamepads (especially older ones) are slightly
mis-aligned; as a result they may not use the full range of values
(for the extremes of the axes), or more annoyingly they may not give 0
when centred.
Calibrating a joystick provides the kernel with information on a
joystick's real behaviour, which allows the kernel to correct various
joysticks' deficiencies and produce consistent output as far as
joystick-using software is concerned.
jstest(1) is useful to determine whether a joystick is
calibrated: when run, it should produce all 0s when the joystick is at
rest, and each axis should be able to produce the values -32767 and
32767.
Analog joysticks should produce values in between 0 and the extremes,
but this is not necessary; digital directional pads work fine with
only the three values.
SEE ALSO
ffset(1),
jstest(1).
AUTHORS
evdev-joystick
was written by Stephen Anthony, based on VDrift's G25manage tool.
This manual page was written by Stephen Kitt <steve@sk2.org>.