NAME

       ts.conf - Configuration file for tslib, controlling touch screens for embedded devices.

DESCRIPTION

       The idea of tslib is to have a core library that provides standardised services, and a set
       of plugins to manage the conversion and filtering as needed.

       The plugins for a particular touchscreen are loaded automatically by the library under the
       control of a static configuration file, /etc/ts.conf.  /etc/ts.conf gives the library
       basic configuration information. Each line specifies one module, and the parameters for
       that module. The modules are loaded in order, with the first one processing the
       touchscreen data first. For example:

             module_raw input
             module variance delta=30
             module dejitter delta=100
             module linear

MODULE PARAMETERS

       variance
           Tries to do it's best in order to filter out random noise coming from touchscreen
           ADC's. This is achieved by limiting the sample movement speed to some value (e.g. the
           pen is not supposed to move quicker than some threshold).

           This is a 'greedy' filter, e.g. it gives less samples on output than receives on
           input.

           •   Parameters: delta.

               Set the squared distance in touchscreen units between previous and current pen
               position (e.g. (X2-X1)^2 + (Y2-Y1)^2). This defines the criteria for determining
               whenever two samples are 'near' or 'far' to each other.

               If the distance between previous and current sample is 'far', the sample is marked
               as 'potential noise'. This doesn't mean yet that it will be discarded; if the next
               reading will be close to it, this will be considered just a regular 'quick motion'
               event, and it will sneak to the next layer. Also, if the sample after the
               'potential noise' is 'far' from both previously discussed samples, this is also
               considered a 'quick motion' event and the sample sneaks into the output stream.

       dejitter
           Removes jitter on the X and Y co-ordinates. This is achieved by applying a weighted
           smoothing filter. The latest samples have most weight; earlier samples have less
           weight. This allows to achieve 1:1 input->output rate.

           •   Parameters: delta.

               Squared distance between two samples ((X2-X1)^2 + (Y2-Y1)^2) that defines the
               'quick motion' threshold. If the pen moves quick, it is not feasible to smooth pen
               motion, besides quick motion is not precise anyway; so if quick motion is detected
               the module just discards the backlog and simply copies input to output.

       linear
           Linear scaling module, primarily used for conversion of touch screen co-ordinates to
           screen co-ordinates.

           •   Parameters: xyswap.

               Interchange the X and Y co-ordinates -- no longer used or needed if the new linear
               calibration utility ts_calibrate is used.

ENVIRONMENT VARIABLES

       Latest versions of the Xorg tslib input driver use hal to configure the touchscreen within
       Xorg. Environment variables are only needed for the tslib commands.

       TSLIB_TSDEVICE
           If the default touchscreen device cannot be found, set the TSLIB_TSDEVICE environment
           variable to the touchscreen device to use.

           Default: /dev/input/event0

       TSLIB_CONSOLEDEVICE
           Tslib default console device.

           Default: /dev/tty

       TSLIB_CALIBFILE
           Stores calibration data obtained using ts_calibrate.

           Default: /etc/pointercal

       TSLIB_CONFFILE
           Set a different location for the ts.conf configuration file itself.

           Default; /etc/ts.conf.

       TSLIB_FBDEVICE
           Framebuffer device to use for the touchscreen support.

           Default: /dev/fb0.

       TSLIB_PLUGINDIR
           Plugin directory for tslib.

           Default: /usr/lib/$triplet/ts0/ where triplet is the MultiArch path, e.g.
           arm-linux-gnueabi.

AUTHOR

       This manual page was written by Neil Williams codehelp@debian.org for the Debian(TM)
       distribution because the original program does not have a manual page, but may be used by
       others. Permission is granted to copy, distribute and/or modify this document under the
       terms of the GNU General Public License, Version 2 any later version published by the Free
       Software Foundation.

       On Debian systems, the complete text of the GNU General Public License can be found in
       /usr/share/common-licenses/GPL.

AUTHOR

       Russell King
           Author.

COPYRIGHT

       Copyright © 2008 Neil Williams