Calibrate the touchscreen

Calibrate with xinput-calibrate (recommended)

* Install xinput calibrator

sudo add-apt-repository ppa:tias/xinput-calibrator-ppa
sudo apt-get update
sudo apt-get install xinput-calibrator

Then execute the xinput calibrator with some precalibration values, e.g.

xinput_calibrator --output-type xorg.conf.d --precalib 34 940 54 900 

Copy the results to the /usr/lib/X11/xorg.conf.d/10-evtouch.conf (MinX MaxX MinY MaxY)

Hint: This procedure was successfully tested for Ubuntu 10.04 LTS.

Calibrate with evtouch

  • The calibration utility is at /usr/lib/xf86-input-evtouch/
  • Copy /usr/share/xf86-input-evtouch/empty_cursor.xbm to /

sudo cp /usr/share/xf86-input-evtouch/empty_cursor.xbm /

This seems to be a bug of the calibration tool.

  • Then create the directory the calibration data is stored in:

sudo mkdir /etc/evtouch 
  • Start calibration: BR

cd /usr/lib/xf86-input-evtouch
sudo ./ 

and follow the instructions

  • Copy the four values MINX, MINY, MAXX, MAXY in /etc/evtouch/config to the corresponding lines in /usr/share/hal/fdi/policy/20thirdparty/50-tsc.fdi
  • Restart XServer
  • The touchscreen must be run in native resolution (640x480), otherwise calibration won't work!

Problems when using the cob_touch and the Care-O-bot 3 touchscreen respectively

After update to ubuntu 10.04, Touchscreen seems to be not calibrated

If you touch the screen, the mouse arrow is showing at a largely different position as expected. You get an error like this in /var/log/Xorg.0.log:

(**) EVTouch TouchScreen: always reports core events
(II) XINPUT: Adding extended input device "EVTouch TouchScreen" (type: TOUCHSCREEN)
(**) Option "Device" "/dev/input/mouse1"
(EE) ioctl EVIOCGNAME failed: Inappropriate ioctl for device
Unable to query/initialize EVTouch hardware.
[dix] couldn't enable device 10


  • Enter the following lines into the file /usr/lib/X11/xorg.conf.d/10-evtouch.conf:

Section "InputClass"
        Identifier "touchscreen catchall"
        MatchIsTouchscreen "on"
        MatchDevicePath "/dev/input/event*"
        Driver "evtouch"
        Option "MinX" "34"
        Option "MaxX" "940"
        Option "MinY" "54"
        Option "MaxY" "900"
        #Option "Emulate3Buttons" "true"
        Option "Emulate3Timeout" "50"
        Option "SwapX" "0"
        Option "SwapY" "0"
        Option "SendCoreEvents" "on"
        Option "ReportingMode" "raw"

Wiki: cob_touch (last edited 2012-11-19 18:55:17 by TobiasSing)