Raspberry Pi - a box full of opportunities

Raspberry Pi - The everything computer.

This post is more or less an installation protocol, how we set up a Raspberry Pi with a 3.5" display in kiosk mode.

Let's get started!

Basic setup of the Raspberry Pi

• The most convenient way to provision the SDCard is to use the Raspberry Pi Imager.

If configured correctly, you can connect to the Raspberry Pi via SSH. Log in and get the system up to date:

sudo apt update && sudo apt upgrade -y

Raspberry Pi with a 3.5" Display

To keep the setup small, we use a Raspberry Pi with a 3.5" (touch) display (and a matching case):

• 3,5" Display für Raspberry Pi mit resistivem Touchscreen
• Gehäuse für Raspberry Pi 4 und 3,5" Display, schwarz

The display needs additional configuration - check goodtft/LCD-show for more details.

Prerequisites:

sudo apt install -y git

The actual installation (requires a lot of trust in the script(s) LCD35-show and a reboot):

git clone https://github.com/goodtft/LCD-show.git
chmod -R 755 LCD-show
cd LCD-show/
sudo ./LCD35-show

So far, so good, but the display is upside down. Let's fix this:

sudo ./rotate.sh 180

It's such a pity - not working out of the box 🤯 - well, let's try this another day and keep the orientation for now.

Maybe we have more luck with the touchscreen functionality (xinput calibrator):

sudo apt-get install xinput-calibrator -y

Spin up the calibration helper from the command line DISPLAY=:0 xinput_calibrator and follow the instructions (on the display).

Sample configuration for the touch screen in /etc/X11/xorg.conf.d/99-calibration.conf:

Section "InputClass"
  Identifier    "calibration"
  MatchProduct  "ADS7846 Touchscreen"
  Option        "Calibration"  "3998 274 183 3861"
  Option        "SwapAxes"  "0"
EndSection

...and (optionally) a virtual keyboard:

sudo apt install matchbox-keyboard -y

Running the Raspberry Pi in Kiosk Mode

There already are a lot of tutorials out there:

• How to use a Raspberry Pi in kiosk mode
• Configure a Raspberry Pi as a kiosk display

Tip: Use sudo raspi-config to configure the Raspberry Pi to boot into the desktop environment with auto-login (if not already done). The configuration is located under System Options -> Boot / Auto Login.

DISPLAY=:0 /usr/bin/chromium-browser \
    --noerrdialogs \
    --disable-infobars \
    --kiosk https://devops.datenkollektiv.de &

Tuning the Kiosk Mode

Tip: With unclutter, you can hide the mouse cursor after some time of inactivity: DISPLAY=:0 unclutter -idle 0.5 -root &.

sudo apt-get install --no-install-recommends unclutter

Autostart

The autostart functionality is configurable via /etc/xdg/lxsession/LXDE-pi/autostart:

@lxpanel --profile LXDE-pi
@pcmanfm --desktop --profile LXDE-pi
@xscreensaver -no-splash
@point-rpi
@/usr/bin/chromium-browser --noerrdialogs --disable-infobars --kiosk https://devops.datenkollektiv.de

Tip: You can start other applications, too - e.g. with bash: @bash /path/to/script.sh.