4inch DPI LCD (C)
- 1 Introduction
- 2 Features
- 3 How to use
- 4 Rotation(Working with Raspberry Pi)
- 5 Others
- 6 Interface
- 7 Resource
- 8 FAQ
- 9 Anti-Piracy
- 10 Beware of knock-offs
- 11 Support
4inch Square Capacitive Touch Screen LCD (C) For Raspberry Pi, 720×720, DPI, IPS, Toughened Glass Cover, Low Power Solution
- 4inch IPS Display， 720x720 hardware resolution.
- Designed for Raspberry Pi, based on Raspberry Pi 40pin GPIO interface.
- Using DPI666 interface of Raspberry Pi to drive LCD, refresh rate up to 60Hz.
- Drive capacitive touch through I2C interface of Raspberry Pi, 5-points touch, toughened glass panel, hardness up to 6H.
- Supports Raspbian and Kali systems.
How to use
This LCD can support Raspbian and Kali systems.
Please download the latest version of the image on the Raspberry Pi official website.
1) Download the compressed file to the PC, and unzip it to get the .img file.
2) Connect the TF card to the PC, use SDFormatter.exe software to format the TF card.
3) Open the Win32DiskImager.exe software, select the system image downloaded in step 1, and click‘Write’ to write the system image.
4) After the image has finished writing, open the config.txt file in the root directory of the TF card(/boot/), add the following code at the end of config.txt, then save and quit the TF card safely.
gpio=0-9=a2 gpio=12-17=a2 gpio=20-25=a2 dtoverlay=dpi24 enable_dpi_lcd=1 display_default_lcd=1 extra_transpose_buffer=2 dpi_group=2 dpi_mode=87 dpi_output_format=0x7f216 dpi_timings=720 0 46 2 42 720 0 16 2 18 0 0 0 60 0 60000000 6 dtoverlay=waveshare-4dpic-3b-4b dtoverlay=waveshare-4dpic-3b dtoverlay=waveshare-4dpic-4b
Note: For Raspberry Pi 4, you need to comment out dtoverlay=vc4-fkms-V3D.
5)Download the 4inch DPI LCD (C) DTBO file and extract 3 dtbo files. Copy these three files to the overlays directory (/boot/overlays/), as shown in the following figure:
6) Save and quit the TF card safely, and insert the TF card into the Raspberry Pi.
7) Insert the 4inch DPI LCD (C) into the 40PIN GPIO interface of the Raspberry Pi, power on the Raspberry Pi, and wait for about ten seconds to display normally.
Rotation(Working with Raspberry Pi)
Add this statement in the config.txt file (the config file is located in the root directory of the TF card, which is named /boot):
display_rotate=1 #1：90；2: 180； 3: 270
And then restart the Raspberry Pi after saving.
After the display is rotated, the position of touch is incorrect because the touch doesn’t change with the display angle. So the touch also needs to be modified.
sudo apt-get install xserver-xorg-input-libinput
If the system you installed is Ubuntu or Jetson Nano. The installation code is:
sudo apt install xserver-xorg-input-synaptics
2.Create the xorg.conf.d directory under /etc/X11/ (if the directory already exists, proceed directly to step 3).
sudo mkdir /etc/X11/xorg.conf.d
3.Copy the 40-libinput-conf file to the directory you created just now.
sudo cp /usr/share/X11/xorg.conf.d/40-libinput.conf /etc/X11/xorg.conf.d/
4.Edit this file.
sudo nano /etc/X11/xorg.conf.d/40-libinput.conf
Find the part of the touchscreen, add the following statement inside, and then save the file.
Option "CalibrationMatrix" "0 1 0 -1 0 1 0 0 1"
Similar to the picture below:
After completing these steps. The LCD could rotate 90 degrees both display and touch function.
90 degree: Option "CalibrationMatrix" "0 1 0 -1 0 1 0 0 1"
180 degree: Option "CalibrationMatrix" "-1 0 1 0 -1 1 0 0 1"
270 degree: Option "CalibrationMatrix" "0 -1 1 1 0 0 0 0 1"
Disable power saving.
If you want to keep the display turning on all the time, you can disable the power saving function.
Modify file lightdm.conf
sudo nano /etc/lightdm/lightdm.conf
Find the [SeatDefaults] option and uncomment the line"xserver-command", modify it as below:
Modify this code to
xserver-command=X -s 0 -dpms
- -s # –Disable the display protecting.
- dpms Disable power saving.
Turn on/off HDMI output
You can use the following commands to disable/enable the displaying.
vcgencmd display_power 0 vcgencmd display_power 1
Adjust brightness by PWM
Update wiringPi if you use Pi4.
wget https://project-downloads.drogon.net/wiringpi-latest.deb sudo dpkg -i wiringpi-latest.deb gpio -v # It should be 2.52 version
Change the brightness by the following command
gpio -g mode 18 pwm #Set the pin for PWM gpio pwmc 100 gpio -g pwm 18 0 #Bightest gpio -g pwm 18 1023 #Dimest gpio -g mode 18 out #Clean the GPIO
The pins labeled "NC" below means that those pins of Raspberry Pi are not occupied by the LCD, and the user can use them for other applications.
|1||NC||Power positive (3.3V power input)|
|2||5V||Power positive (5V power input)|
|4||5V||Power positive (5V power input)|
|7||B0||RGB signal cable|
|8||G2||RGB signal cable|
|10||G3||RGB signal cable|
|11||G5||RGB signal cable|
|13||TP_INT||Touch Panel interrupt|
|15||R2||RGB signal cable|
|16||R3||RGB signal cable|
|17||NC||Power positive (3.3V power input)|
|18||R4||RGB signal cable|
|19||TP_SDA||I2C SDA for touch panel|
|21||B5||RGB signal cable|
|22||R5||RGB signal cable|
|23||TP_SCL||I2C SCL for touch panel|
|24||B4||RGB signal cable|
|26||B3||RGB signal cable|
|28||DE||LCD data enable|
|29||B1||RGB signal cable|
|31||B2||RGB signal cable|
|32||G0||RGB signal cable|
|33||G1||RGB signal cable|
|36||G4||RGB signal cable|
|38||R0||RGB signal cable|
|40||R1||RGB signal cable|
Since the first-generation Raspberry Pi released, Waveshare has been working on designing, developing, and producing various fantastic touch LCDs for the Pi. Unfortunately, there are quite a few pirated/knock-off products in the market. They're usually some poor copies of our early hardware revisions, and comes with none support service.
To avoid becoming a victim of pirated products, please pay attention to the following features when purchasing:
Beware of knock-offs
Please note that we've found some poor copies of this item in the market. They are usually made of inferior materials and shipped without any testing.
You might be wondering if the one you're watching or you've purchased in other non-official stores is original, feel free to contact us.