AXEL Lite SOM/DESK-MX6-L/Deployment/Touchscreen Calibration

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Version Issue Date Notes
1.0.0 Jun 2021 First DESK release


Touchscreen calibration[edit | edit source]

For resistive touch some calibration may be needed. Depending on your touchscreen and or the usespace environment, different calibration mechanism has to be used.

Weston[edit | edit source]

If the Weston compositor is running in the background, it is necessary to remove the old udev rules, and restart the device in order to calibrate the touchscreen.

 rm -f /etc/udev/rules.d/ws-calibrate.rules
 reboot

At the next restart the weston-calibrator tool should automatically show up. Tap on the red cross appearing on the screen to calibrate the touch panel.

Note: In the case of root filesystem over NFS and SD card plugged in, make sure delete also the calibration rules stored in the SD card partition before rebooting:

 rm /etc/udev/rules.d/ws-calibrate.rules
 rm /run/media/mmcblk0p1/ws-calibrate.rules
 reboot

Non-Weston based Graphic System[edit | edit source]

If the weston compositor is not running, it is necessary to run ts_calibrate exporting the correct environment variable for the calibration file used:

   export TSLIB_CALIBFILE=/usr/share/pointercal
   ts_calibrate

Exporting TSLIB_CALIBFILE[edit | edit source]

The environment variable TSLIB_CALIBFILE is used by the tslib package to indicate the location of the pointercal file. The default value for TSLIB_CALIBFILE is /etc/pointercal. If you are writing a program that uses tslib you should make sure that you export TSLIB_CALIBFILE to point to the location of your pointercal file (as indicated in the previous section), or that you place a copy of the pointercal file at the default /etc/pointercal location.

Additional information can be found int the following page in TI wiki