RPi - eGalax Touchscreen with Raspberry
(posted 2020.02.13, last updated 2020.02.13)

Goal

Years ago I purchased a touch display for my Pi but for whatever reasons I never used it. Now I got another Pi 3 Mod B+ to tinker with.

Hardware

Raspberry Pi 3 Mod B+
eGalax 7" Resistive 1024x600 Touchscreen / Pollin LCD Set LS-7T https://www.pollin.de/p/7-17-78-cm-display-set-mit-touchscreen-ls-7t-hdmi-dvi-vga-cvbs-120964

Steps

Raspbian: 2020-02-05-raspbian-buster

Fix Resolution /boot/config.txt

  framebuffer_width=1024
  framebuffer_height=600
  hdmi_force_hotplug=1
  hdmi_cvt=1024 600 60 3 0 0 0
  hdmi_group=2
  hdmi_mode=87

Get Touch to work

sudo apt-get install xserver-xorg-input-evdev

nano /etc/X11/xorg.conf

  Section "InputClass"
      Identifier "evdev tablet catchall"
      MatchIsTablet "on"
      MatchDevicePath "/dev/input/event*"
      Driver "evdev"
  EndSection

Touch Calibration

  sudo apt-get install libx11-dev libxext-dev libxi-dev x11proto-input-dev
  wget http://github.com/downloads/tias/xinput_calibrator/xinput_calibrator-0.7.5.tar.gz
  tar -zxvf xinput_calibrator-0.7.5.tar.gz
  cd xinpit_calibrator*
  ./configure
  make
  sudo make install
  xinput_calibrator

Copy output to specified config file for permanent calibration.

References

Touchscreen Resolution

(de) https://christian-brauweiler.de/carpi-touchscreen-konfigurieren/

Pollin LCD Set LS-7T

eGalax Touchscreen with rPi

Misc

(de) http://web.archive.org/web/20160316112025/http://www.saudumm.me/raspberry-pi-touch-displays-kalibrierung/