3.5/4 inch HDMI LCD
HDMI Touchscreen
Introduction
This guide introduces how to bring up 3.5"/4" HDMI touchscreen on Tinker Borad.
The devices are made by Waveshare with 800x480 high resolution, resistive touch control and IPS screen.
For more details, please visit "https://www.waveshare.com/wiki"
Outlines
- Porting kernel driver
- Setup configurations
Porting steps
a. Porting kernel driver
First, add the touch device into kernel:
# Add the dts overlay for Ads7846 touch IC
$ cp ads7846-tinker-overlay.dts {codebase}/kernel/arch/arm/boot/dts/overlays
$ cp Makefile {codebase}/kernel/arch/arm/boot/dts/overlays
Then add the line into the end of miniarm-rk3288_defconfig:
# The file in {codebase}/kernel/arch/arm/configs/miniarm-rk3288_defconfig
$ CONFIG_TOUCHSCREEN_ADS7846=y
To modify kernel is done, please re-build your image and flash for next step.
b. Setup configurations
After reboot your device, modify /boot/hw_intf.conf to load the dts overlay we just added:
intf:dtoverlay=ads7846-tinker
Then install the package required and configure the display settings:
# This package should be installed in the default image $ sudo apt-get install xserver-xorg-input-evdev $ sudo cp -rf /usr/share/X11/xorg.conf.d/10-evdev.conf /usr/share/X11/xorg.conf.d/45-evdev.conf $ sudo cp 99-calibration.XX /usr/share/X11/xorg.conf.d/99-calibration $ sync; sudo reboot XX = the size of your HDMI touchscreen 3.5 inch = 35 4 inch = 40
After reboot, you should see the display on the touchscrenn and the touch function should work.
Reference
"http://www.waveshare.net/wiki/4inch_HDMI_LCD"
"https://www.waveshare.com/wiki/4inch_HDMI_LCD"
"http://www.waveshare.net/wiki/3.5inch_HDMI_LCD"
"https://www.waveshare.com/wiki/3.5inch_HDMI_LCD"
Media:LCD.7z
