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WSAL21433 – 4inch HDMI LCD (C)/en

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Version vom 6. September 2026, 00:38 Uhr von JWTechPublisher (Diskussion | Beiträge) (Freigegebene technische Dokumentation veröffentlicht; Text-only und noindex)
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Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

Summary

Technical guide for the Waveshare 4-inch HDMI LCD (C) with capacitive touch, IPS panel and optical bonding. Covers hardware connection to Raspberry Pi, PC and Jetson Nano, plus software configuration steps.

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Technical overview

  • Resolution: 720 × 720 pixels on a 4-inch IPS panel with optical bonding.
  • Touch: 5-point capacitive touch with toughened glass, hardness up to 6H.
  • Interfaces: HDMI for video/audio, USB or I2C for touch, 3.5 mm audio and speaker connector.
  • Compatibility: Works with Raspberry Pi OS, Ubuntu, Kali and Retropie; with PC under Windows 11/10/8.1/8/7; with Jetson Nano under Ubuntu.
  • Raspberry Pi hardware connection: Set the touch switch to “I2C”, mount the Pi via copper posts, connect HDMI; Pi Zero requires an additional HDMI cable.
  • Software setup: Download the latest official Raspberry Pi image, format and write the TF card, then extend config.txt in the boot partition root directory.
  • DTBO files: Copy the three downloaded .dtbo files into /boot/overlays/.
  • PC usage: Switch the touch selector to “USB”, connect Power&Touch to a PC USB port and the display to a PC HDMI port.

Commands and examples – verify before use:  

dtparam=i2c_arm=on
dtoverlay=waveshare-4dpic-3b
dtoverlay=waveshare-4dpic-4b
dtoverlay=waveshare-4dpic-5b
hdmi_force_hotplug=1
config_hdmi_boost=10
hdmi_group=2
hdmi_mode=87
hdmi_timings=720 0 100 20 100 720 0 20 8 20 0 0 0 60 0 48000000 6
start_x=0
gpu_mem=128
disable_splash=1
wget https://files.waveshare.com/upload/1/18/Evdev-right-click-emulation.zip
unzip Evdev-right-click-emulation.zip
cd evdev-right-click-emulation
sudo apt install build-essential libevdev2 libevdev-dev -y
sudo cp 'out/evdev-rce' '/usr/local/bin/'
sudo chmod +x '/usr/local/bin/evdev-rce'
sudo evdev-rce
sudo usermod -G 'input' -a pi
echo 'uinput' | sudo tee -a /etc/modules
sudo nano /etc/udev/rules.d/99-uinput.rules
KERNEL=="uinput", MODE="0660", GROUP="input"
sudo udevadm control --reload-rules
sudo udevadm trigger
sudo reboot
evdev-rce
sudo mkdir ~/.config/autostart
sudo nano ~/.config/autostart/right_click.desktop
[Desktop Entry]
Version=1.0
Type=Application
Name=evdev-rce
GenericName=Enable long-press-to-right-click gesture
Exec=env LONG_CLICK_INTERVAL=1000 LONG_CLICK_FUZZ=200 /usr/local/bin/evdev-rce
Terminal=true
StartupNotify=false

Notes and version constraints

  • The exact DTBO file names depend on the Raspberry Pi model; select the correct overlay for your board.
  • Replacing the boot logo requires filesystem access; this may be limited on some systems.
  • The long-press right-click feature is stated to support only 32-bit systems by default; 64-bit is not supported.
  • PWM backlight control requires removing the original soldered resistor; consult the original documentation for exact pad connections.
  • The speaker connector supports 8 Ω / 5 W; higher loads may damage the amplifier.
  • If other operating systems show issues, first use Raspberry Pi OS to adjust DISABLE_HDMI before switching back.
  • Beware of knock-offs: purchase only from official channels, as pirated copies ship without testing or support.

Source and revision record

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