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Calibrate a touchscreen


calib [options]

Runs on:



-a alg
Specify the calibration algorithm. Valid algorithms are 3 and 4. Default value is 3.
-b val
Specify the touch point acceptance variance (range 0 - 2000). Enabling this will force bound checking on touch points.
Don't run if a configuration file already exists at /etc/system/config/calib.$(hostname).
-d w,h
The width and height of the screen to be calibrated. If you don't specify this option, calib attempts to get this information from the hardware.
-f file
The name and location of a calibration file to create instead of the default at /etc/system/config/calib.$hostname.
-l limit
Limit the number of samples for each touch point. Default value is 15.
-o offset
Offset for crosshair position, which you can use to tweak calibration. Applicable only with 4-point calibration.
The Origin. Touch screen origin (0,0) is at the lower right side. Default is upper left corner.
-p x, y
The offset position of the calibration region.
Supress prompts (no text is displayed on screen). Prompts are on by default.
-s server
The server node or the device name.
Use small touch targets. Default is large.
-t timer
The done button timer value. Default value is 10.
Verbose output.
-x x
The initial x position.
-y y
The initial y position.


The calib utility is used to calibrate a touchscreen. Once the touchscreen is successfully configured (i.e. you've created an input.node file), it must be calibrated. The calib utility saves a configuration file at /etc/system/config/calib.$hostname. For information about this file format, see the “Calibration file format” section of the “Writing an Input Device Driver” chapter of the Input DDK documentation.

To invoke the calibration screen:

  1. Start Photon.
  2. Run calib.
  3. Touch the bullseye target on the screen.
  4. Touch the Press to Complete Calibration button to finish calibration.


Calibrate a quarter of a standard 640x480 VGA screen (the driver will cover only part of the screen):

calib -d 320,240