4.3inch DSI LCD Screen

Features

  • 800*480 resolution capacitive touch IPS screens
  • Raspberry Pi MIPI DSI interface direct output, plug and play, no need to install driver
  • Support for official system Raspbian, 2 points to zoom the page
  • Support Ubuntu/Kali/Win10 IoT, single touch
  • Support Retropie
  • Backlight brightness adjustment button
  • Support PWM backlight brightness adjustment, adapt to different use environment

Hardware Description

1）Backlight brightness adjustment button

2）MIPI DSI interface
MIPI DSI interface for connecting Raspberry Pi via FPC flexible cable
3）Backlight control mode selection
The circuit is used to choose the mode of fixed maximum brightness value or
the mode of adjusting brightness value through PWM：

  • The 0R resistor is soldered to the right, then the maximum brightness value is fixed to control the backlight;
  • The 0R resistor is welded to the left, then the backlight is controlled by adjusting the brightness value through PWM.

Note: The default option is to set the maximum brightness value to control the backlight
4）External PWM access point
Used for external PWM control signal input, you can control the screen
backlight brightness through the PWM signal. Where the PWM point is connected
to the GPIO (such as GPIO18) that outputs the PWM signal, and the GND point
is connected to the GND pin.

Module Size

R is the radius of the mounting hole of the positioning column

How to use

The module can be driven directly using the official original image without any
modifications.

Here are the steps to use the module on Raspberry Pi:
1) Download the latest Raspberry Pi system image from the official website (https://www.raspberrypi.org/downloads/) to your PC. Extract the file to obtain an.img file.
2) Prepare a Micro SD card (at least 8GB). Insert it into the PC using a card reader. Open SDFormatter software, select the target SD card, and click the Format button to format it.
3) After formatting, open Win32DiskImager software. Select the Micro SD card inserted on the PC as the device. Then select the decompressed IMG image file. Finally, click Write to burn the image.

4）Remove the SD card from the PC and insert it into the SD card slot of the Raspberry Pi.
5) Install the Raspberry Pi into the display module. First, install four copper columns to the positioning column (refer to Figure 3). Then, use four M2.5 screws to fix the Raspberry Pi to the copper column. Connect the DISPLAY module to the Raspberry Pi Display interface (J4 interface) via a 5cm FPC flexible cable (refer to Figure 4). Finally, connect the power cord to the Raspberry Pi.
6) Power on the Raspberry Pi. The program should run normally. The module will have display screen output and normal touch function.

Note:
1）Product accessories include copper columns, screws, and 15PIN FPC wiring.
2）As shown in Figure 4, the installation of Raspberry Pi 4 is demonstrated. The installation method of Raspberry Pi 3 is largely the same as that of Raspberry Pi 4. The sole difference lies in the connected power cord. Raspberry Pi 4 uses a Type-C cable while Raspberry Pi 3 uses a Micro USB cable.

How to use PWM to control backlight brightness

1) Make the hardware connection first. Adjusting mode according to the hardware
specifications, backlit by PWM adjust brightness value way, so to backlight control mode selection circuit of resistance welding to the PWM control circuit, the next on the PWM & GND access points respectively welding dubond thread (as shown in Figure 5), finally will PWM access points connected to the output PWM signals of Raspberry Pi GPIO (select GPIO18), connect GND access points to Raspberry Pi GND pin.

2) Software adjustment. The first step (which you can ignore if you have already done it) is to connect the SD with the official image to your PC, then create a new SSH file in the root directory of the SD card, pop the SD card out, and insert it into the Raspberry Pi. The above steps are to prepare for an SSH connection. Next, open the PC terminal software (such as PuTTY, Securecrt, etc.), select the SSH protocol, enter the Raspberry Pi IP address and log in to the Raspberry Pi terminal (the IP address can be viewed through the router's web page or be viewed on the Raspberry Pi through the relevant module).

3) On the Raspberry Pi terminal, enter the following command to adjust the PWM backlight brightness (select GPIO18 here, and other idle GPIO can also be selected) :

gpio -g pwm 18 1024

gpio -g mode 18 pwm 

gpio pwmc 1000

gpio -g pwm 18 X （Control the brightness, X value between 0 and 1024）

In addition, add the following content at the end of /boot/config.txt file to make the display module boot. PWM will reach its maximum value to achieve the maximum brightness of the display screen.

gpio=18=op,pu
Note:
Backlight control on Raspberry Pi 4 may fail. If Raspberry Pi requires an Internet connection, you need to update the WiringPi GPIO library by typing the following command.
cd /tmp
wget https://project-downloads.drogon.net/wiringpi-latest.deb
sudo dpkg -i -B wiringpi-latest.deb

Display direction rotation

There are two kinds of display direction rotation: FKMS mode direction rotation and traditional graphics mode direction rotation.

Method 1: FKMS mode direction rotation.

FKMS mode is used by default on Raspberry Pi 4B. When using this mode, make sure that “dtoverlay = vc4-fkms-v3d” in the /boot/config.txt file under pi4 is not commented out. In this mode, the display direction can only be rotated by menu options (Figure 6, Figure 7). Note that when setting the display direction in the menu, it is recommended to use the mouse for operation.

Method 2: Traditional graphics mode
By default, the Raspberry Pi 3, 2, and 1 series use traditional graphics mode. Raspberry Pi 4B can also use traditional graphics mode. Just add relevant settings in the /boot/config.txt file under the Pi 4.

 dtoverlay=vc4-fkms-v3d

Comment out, as shown in Figure 8. (Traditional graphics mode is generally not recommended on Raspberry Pi 4B.) In traditional graphics mode, this can be done by adding [what needs to be added] at the end of the /boot/config.txt file.

 display_lcd_rotate=x（x=0,1,2,3,0x10000,0x20000）

To set the display orientation, reboot is required to take effect (Figure 9).

                                              Figure 8

 

 

                                               Figure 9

 display_lcd_rotate=0, The default normal display direction (no rotation);
display_lcd_rotate=1, Rotate 90° clockwise;
display_lcd_rotate=2, Rotate 180° clockwise;
display_lcd_rotate=3, Rotate 270° clockwise;
display_lcd_rotate=0x10000, Flip horizontal;
display_lcd_rotate=0x20000, Flip vertical;

Touch direction rotation

The display direction is set, and the touch direction should be set accordingly. It needs to correspond with the display direction, otherwise the touch operation is not accurate. Touch direction setting needs to be in the /usr/share/X11/xorg.conf.d/40-libinput.conf file. Add the content 'Option "CalibrationMatrix" "XXX"' to this file, where XXX is the set parameter for the touch direction. The following will show (as shown in Figure 10).

Open the 40-libinput.conf file:

 sudo nano /usr/share/X11/xorg.conf.d/40-libinput.conf

                                              Figure 10

After the modification, press Ctrl +X, Y, and Enter to save and exit.

Corresponding relation table of display direction and touch direction:

How to install the virtual keyboard

Execute the following command:

 sudo apt-get install matchbox-keyboard

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