RockpiS/hardware/display
ROCK Pi S > Hardware > Display
Contents
For Waveshare 3.5inch RPI LCD, both display and touch are two spi devices.
Due to the hardware limitation with only one CS for spi2 of ROCK Pi S, Waveshare 3.5inch RPI LCD only supports display but touch.
The Waveshare 3.5inch RPI LCD works as a framebuffer device.
Hardware
Waveshare 3.5inch RPI LCD Model B V2.0.
Waveshare 3.5inch RPI LCD Model C.
Software
We recommend you that you use the system images released after March 1st, 2020.
Step 1: Modifying configuration files.
- (A) For those ROCK Pi S system images released after March 1st, 2020, use configuration file, /boot/uEnv.txt. The related packages include rockchip-overlay, linux-4.4-rockpis-latest, etc. See ROCK Pi S DTBO to know more about uEnv.txt and dtbo. Here is an example for using Waveshare 3.5inch RPI LCD on ROCK Pi S V1.2, adding the following lines in /boot/uEnv.txt.
overlays=rockpis-v11-spi2-waveshare35b-v2
- (B) For those ROCK Pi S system images released after March 1st, 2020, use configuration file, /boot/hw_intfc.conf. See /boot/overlays/README. The related packages include rockchip-overlay, linux-4.4-rockpis-latest, rockpis-dtbo, etc. At first you need to update kernel (>= 4.4.143-43) and rockpis-dtbo (>= 4.5) package. And then add the following lines to the hardware interface config file /boot/hw_intfc.conf to use Waveshare 3.5inch RPI LCD on ROCK Pi S V1.2.
intfc:uart2=off intfc:i2c0=off intfc:spi2=on intfc:dtoverlay=rockpis-v12-spi2-waveshare35c
All Waveshare 3.5inch RPI LCD dtbo for A-class and B-class system images are
rockpis-v11-spi2-waveshare35b-v2 # Waveshare 3.5inch RPI LCD Model B V2.0 on SPI2 for ROCK Pi S V1.1 rockpis-v11-spi2-waveshare35c # Waveshare 3.5inch RPI LCD Model C on SPI2 for ROCK Pi S V1.1 rockpis-v12-spi2-waveshare35b-v2 # Waveshare 3.5inch RPI LCD Model B V2.0 on SPI2 for ROCK Pi S V1.2 rockpis-v12-spi2-waveshare35c # Waveshare 3.5inch RPI LCD Model C on SPI2 for ROCK Pi S V1.2
Step 2: Install required display packages
$ sudo apt-get update $ sudo apt-get install -y xserver-xorg-video-fbdev
Step 3: Modify /etc/X11/xorg.conf.d/20-modesetting.conf
Backup and clean the contents of file, /etc/X11/xorg.conf.d/20-modesetting.conf. Then add the following lines to it:
Section "Device"
Identifier "Rockchip Graphics"
Driver "fbdev"
Option "fbdev" "/dev/fb0"
Option "DRI" "2"
EndSection
You need to checkout the device, "/dev/fb0" or "/dev/fb1".
Reboot ROCK Pi S.
Troubleshooting
- If you have issue with display, start a new post on the forum. https://forum.radxa.com/