Display FAQ
1. No images with a Raspberry Pi 4 after following the user manual to connect all the cables and add all the configuration
If your screen connects to a Raspberry Pi 4 through the HDMI adapter, you need to comment out the line “dtoverlay=vc4-fkms-V3D”. (as shown below)
Before change:
dtoverlay=vc4-fkms-V3D
After change:
#dtoverlay=vc4-fkms-V3D
Then, reinsert the SD card to the Raspberry Pi 4 and it should work.
2. No sound on my screen(with speakers) when used with a Raspberry Pi
• 1. Make sure the speakers are firmly connected to their interfaces.
• 2. Make sure you didn’t set the Raspberry Pi to mute.
• 3. Make sure you have changed the “hdmi_drive =1” to “hdmi_drive=2” in the config.txt file under the /boot folder.
3. Set Your PC/Laptop Monitor to Duplicate or Extend Mode
• 1. Connect the monitor to your PC properly and power it on.
• 2. Right click the desktop and select Screen resolution (Win 7/8) or Display settings (Win 10).
• 3. Click the Multiple display drop-down list, select Extend these displays or Duplicate these
displays.
*If you can’t see the additional monitor listed, please click Detect. If it doesn’t work. Restart
your PC then try again
4. Set Your PC/Laptop to Rotate the Screen
• 1. Connect the monitor to your PC properly and power it on.
• 2. Right click the desktop and select Screen resolution (Win 7/8) or Display settings (Win 10).
• 3. Click the Orientation drop-down list, select Portrait or Landscape screen.
* If you can’t see the option of Orientation on your PC/laptop, please check if your PC/laptop has this function.
5. Screen flickers and blurred
• 1. Make sure you have selected the correct resolution and fresh rate for the screen
• 2. Make sure the screen charge with the power adapter provided by us
• 3. Try another HDMI cable
6. Touch screen doesn’t work
• 1. Make sure you have connected the USB cable(supports data transfer) to the screen’s Touch port
• 2. Try to reconnect the touch cable and restart your device
• 3. Make sure your system has the touch function
7. Disable screen sleep mode when used with a Raspberry Pi
Step 1: Open a terminal and type the command:
sudo nano /etc/lightdm/lightdm.conf
Step 2: Find the'xserver-command' under the [Seat:*] paragraph, uncomment it, and modify it as follows:
xserver-command=X -s 0 -dpms
Step 3: Restart the system
sudo reboot
8. Screen touch function work in the primary screen but not second screen
Step 1: Setup the monitor in Extend mode.
-----Press WIN+P, choose Extend.
Step 2: Set the monitor as the touchscreen.
-----Open the Control Panel -----> All Control Panel Items ----> Tablet PC Settings or Pen and Touch ---->Display/Configure---->Setup---->Touch and choose the external monitor as the touchscreen
*If you don't know how to set up, you can follow this link: https://support.ctouch.eu/hc/en-us/articles/115003949829-How-can-I-setup-multiple-touch-screens-in-Windows-10-
*If you cannot find the “Tablet PC Settings or Pen and Touch ” button, you can follow this link: https://answers.microsoft.com/en-us/windows/forum/windows8_1-hardware/tablet-pc-settings-is-missing/b55ab19d-ee5a-4973-84c5-39aabd723d31
9. Streaks appear when the screen display
Set the correct resolution for the screen. Note that the resolution you set should be lower than or equal to the highest resolution of the screen.