4inch RPi LCD (A)

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4inch RPi LCD (A)
320×480, IPS
4inch-RPi-LCD-A

4 inch Touch Screen TFT LCD Designed for Raspberry Pi
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Introduction

4 inch Touch Screen TFT LCD Designed for Raspberry Pi

More

Features

  • 800×480 hardware resolution
  • Resistive touch control
  • It is compatible and can be directly inserted in any version of Raspberry Pi.
  • Drivers provided (works with your own Raspbian/Ubuntu/Kali and Retropie system directly)
  • Support FBCP software driver, can set the software resolution and dual screen display.
  • IPS screen, with wide viewing angle and outstanding display effect.

Getting Started

Hardware Connection

  • There are 40 pins on Raspberry Pi, but there are 26 pins on the LCD, so you should pay attention to connecting the pins to your Pi accordingly.

Install the touch driver

The RPi LCD can be driven in two ways: Method 1. install driver to your Raspbian OS. Method 2. use the Ready-to-use image file of which LCD driver was pre-installed.

Method 1. Driver installation

Please download the latest version of the image on the Raspberry Pi official website. (Raspbian/Ubuntu Mate/Kali or Retropie)

1) Download the compressed image file to the PC, and unzip it to get the .img file.

2) Connect the TF card to the PC, open the Win32DiskImager software, select the system image downloaded in step 1 and click‘Write’ to write the system image. ( How to write an image to a micro SD card for your Pi? See RPi Image Installation Guides for more details)

3) Connect the TF card to the Raspberry Pi, start the Raspberry Pi. The LCD will display after booting up, and then log in to the Raspberry Pi terminal,(You may need to connect a keyboard and HDMI LCD to Pi for driver installing, or log in remotely with SSH)

4) Then open the terminal of Raspberry Pi to install the touch driver.

git clone https://github.com/waveshare/LCD-show.git
cd LCD-show/

Note: The Raspberry Pi must be connected to the network, or else the touch driver won't be successfully installed.

chmod +x LCD4-show
 ./LCD4-show 

The touch function will work after restart. For ease of use, you can set the screen orientation, see: #Screen orientation settings.

Notes:

  • 1. Executing apt-get upgrade will cause the LCD to fail to work properly. In this case, you need to edit the config.txt file in the SD card and delete this sentence: dtoverlay=ads7846.
  • 2. Using with Raspbian-lite, the command of the touch driver installation should be:
 ./LCD4-show lite

Method 2. Using Ready-to-use image

The image file with pre-installed driver is located in the IMAGE directory of the CD, or you can download it from #Image. Extract the .7z file and you will get an .img file. Write the image to your micro SD card (How to write an image to a micro SD card for your Pi? See RPi Image Installation Guides for more details). Then insert the card to your Pi, power up and enjoy it.


Screen orientation settings

After installing the touch driver, you can modify the screen rotation direction by running the following commands.

cd LCD-show/
#X can be 0, 90, 180 and 270. Indicates that the LCD rotates 0 degrees, 90 degrees, 180 degrees and 270 degrees, respectively.
#If it is an old version, execute the following code:
sudo ./LCD28-show X
#If it is a new version, execute the following code:
sudo ./LCD28-show-V2 X

The rotation command under Raspbian-lite is as follows:

cd LCD-show/
#X can be 0, 90, 180 and 270. Indicates that the LCD rotates 0 degrees, 90 degrees, 180 degrees and 270 degrees, respectively.
#If it is an old version, execute the following code:
sudo ./LCD28-show lite X
#If it is a new version, execute the following code:
sudo ./LCD28-show-V2 lite X

Touch screen calibration

This LCD can be calibrated through the xinput-calibrator program. Note: The Raspberry Pi must be connected to the network, or else the program won't be successfully installed.

  • Run the following command to install:
sudo apt-get install xinput-calibrator 
  • Click the "Menu" button on the taskbar, choose "Preference" -> "Calibrate Touchscreen".
  • Finish the touch calibration following the prompts. Maybe rebooting is required to make calibration active.
  • You can create a 99-calibration.conf file to save the touch parameters (not necessary if file exists).
sudo nano /etc/X11/xorg.conf.d/99-calibration.conf
  • Save the touch parameters (may differ depending on LCD) to 99-calibration.conf, as shown in the picture:

5inch HDMI LCD FAQ1.jpg

Control Backlight Brightness with GPIO

Use a 0R resistor or solder to connect this pad.
Virtual Keyboard Install01.png
Execute the following command on the Raspberry Pi terminal to control the backlight brightness:

gpio -g pwm 18 1024
gpio -g mode 18 pwm (the occupied pins are PWM pins)
gpio pwmc 1000
gpio -g pwm 18 X (control brightness, X value is between 0~1024)


Install Virtual Keyboard

1. Install matchbox-keyboard

sudo apt-get install update
sudo apt-get install matchbox-keyboard
sudo nano /usr/bin/toggle-matchbox-keyboard.sh

2. Copy the statements below to toggle-matchbox-keyboard.sh and save.

#!/bin/bash
#This script toggle the virtual keyboard
PID=`pidof matchbox-keyboard`
if [ ! -e $PID ]; then
killall matchbox-keyboard
else
matchbox-keyboard -s 50 extended&
fi

3. Execute the commands:

sudo chmod +x /usr/bin/toggle-matchbox-keyboard.sh
sudo mkdir /usr/local/share/applications
sudo nano /usr/local/share/applications/toggle-matchbox-keyboard.desktop

4. Copy the statements to toggle-matchbox-keyboard.desktop and save.

[Desktop Entry]
Name=Toggle Matchbox Keyboard
Comment=Toggle Matchbox Keyboard`
Exec=toggle-matchbox-keyboard.sh
Type=Application
Icon=matchbox-keyboard.png
Categories=Panel;Utility;MB
X-MB-INPUT-MECHANSIM=True

5. Execute commands as below. Note that you need to use "Pi " user permission instead of root to execute this command

sudo nano /etc/xdg/lxpanel/LXDE-pi/panels/panel

6. Find the statement which is similar to below: (It maybe different in different version)

Plugin {
type = launchbar
Config {
Button {
id=lxde-screenlock.desktop
}
Button {
id=lxde-logout.desktop
}
}

7. Append these statements to add an button option:

Button {
id=/usr/local/share/applications/toggle-matchbox-keyboard.desktop
}

RPILCD-INSTALL-KEYBOARD01.png

8. Reboot your Raspberry Pi. If the virtual keyboard is installed correctly, you can find that there is a keyboard icon on the left of the bar

sudo reboot



Interface

PIN NO. SYMBOL DESCRIPTION
1, 17 3.3V Power positive (3.3V power input)
2, 4 5V Power positive (5V power input)
3, 5, 7, 8, 10, 12, 13, 15, 16 NC NC
6, 9, 14, 20, 25 GND Ground
11 TP_IRQ Touch Panel interrupt, low level while the Touch Panel detects touching
18 LCD_RS Command/data register selection
19 LCD_SI / TP_SI LCD display/SPI data input of Touch Panel
21 TP_SO SPI data output of Touch Panel
22 RST Reset
23 LCD_SCK / TP_SCK LCD display/SPI clock of Touch Panel
24 LCD_CS LCD chip selection, low active
26 TP_CS Touch Panel chip selection, low active

Resources

User Manual

Image

Description: if you felt hard to install the driver, try the image with the driver pre-installed.


Driver

The driver can be downloaded from github

git clone https://github.com/waveshare/LCD-show.git

Software

Diemension

FAQ

 Answer:
The LCD must have a driver installed for normal use. For details, please refer to the relevant introduction in the user manual.
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 Answer:
Since the Raspberry Pi image and version are frequently updated, if you encounter a situation where the LCD cannot be used normally, please download the latest version of the image provided by us or from the official website of Raspberry Pi and install the latest driver provided by us.
  • Make sure the hardware connection is correct and the contact is good.
  • Make sure that TF card programming is normal.
  • When the Raspberry Pi starts normally, the PWR light is always on, and the ACT light is flashing. If it is found that both lights are always on, it may be that the TF card is not successfully programmed to the image or the TF card is in poor contact with the Raspberry Pi.
  • It is recommended to use a 5V 2.5A power adapter for the Raspberry Pi. If the Raspberry Pi is powered by the USB port of the PC, the Raspberry Pi may not be able to start normally due to an insufficient power supply.
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 Answer:
Commercial grade (0~70 degrees Celsius).
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 Answer:
When working with 5V input, the current is about 200mA.
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 Answer:
when working with 5V input, the current is about 200mA.
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Anti-Piracy

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:

RPi-LCD-Anti-Piracy.jpg

(Click to enlarge)

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.

Support