CUQI Raspberry Pi 4 Touchscreen Display Kit User Manual

1. Product Overview

This manual provides instructions for the CUQI 3.5-inch touchscreen display kit designed for Raspberry Pi 4. The kit includes a 3.5-inch display with 480x320 resolution, a protective case, a mini cooling fan, and heatsinks to ensure optimal performance and heat dissipation for your Raspberry Pi 4.

The display supports a 125MHz SPI signal input, offering a refresh rate of approximately 60 frames per second, suitable for video playback and gaming without noticeable flicker. It features a resistive touch interface for interactive control.

2. Package Contents

Please verify that all the following components are included in your package:

• 3.5-inch Touchscreen Display (1)
• Protective Case for Raspberry Pi 4 (1)
• Mini Cooling Fan (1)
• Heatsinks (3)
• Screws (6)
• Rubber Feet (1 set)
• White Balance Column (1)
• Square Patch (1)
• Touch Pen (1)

Image: All items included in the CUQI Raspberry Pi 4 touchscreen kit: protective case, 3.5-inch screen, touch pen, heat-sinks, rubber feet, balance column, balance square, and mini fan.

3. Setup Instructions

Follow these steps to assemble your CUQI touchscreen display kit and install the necessary drivers for your Raspberry Pi 4.

3.1 Hardware Assembly

1. Install Heatsinks: Apply the heatsinks to the appropriate chips on your Raspberry Pi 4 board.
2. Install Mini Fan: Attach the mini cooling fan to the designated pins on the Raspberry Pi board. Ensure proper orientation for airflow.
3. Mount Raspberry Pi in Case: Carefully place the Raspberry Pi 4 board into the bottom part of the protective case.
4. Connect Touchscreen: Align the 3.5-inch touchscreen with the GPIO pins on the Raspberry Pi 4 and gently press it into place. Ensure all pins are correctly seated.
5. Secure Case: Attach the top part of the protective case and secure it with the provided screws.

Image: An exploded diagram illustrating the individual components of the CUQI display kit: the bottom case, Raspberry Pi board, 3.5-inch touchscreen, and top case. It highlights how the components fit together, with a focus on the connection points.

Image: A transparent view demonstrating the placement of the mini cooling fan on the Raspberry Pi 4 board, beneath the touchscreen. Arrows indicate airflow for heat dissipation.

3.2 Driver Installation

There are two methods for installing the display driver:

Mode 1: Using a Pre-configured System Image (Recommended for beginners)

If you are unfamiliar with driver installation, it is recommended to use a pre-configured system image that includes the necessary drivers. This simplifies the setup process.

1. Download the pre-configured image with the driver directly from the provided link: https://mega.nz/#!Ojp2ACyI!dn4Gt5OibU2pzN9AvwzQXg4PSSYmh3mMxXnvgNVbgT0
2. Burn this image to your Micro SD card using a tool like Win32DiskImager or Raspberry Pi Imager.
3. Insert the Micro SD card into your Raspberry Pi 4, connect power, and the system will boot with the display working.

Mode 2: Manual Driver Installation

If you prefer to install the driver on an existing Raspbian Buster installation, follow these steps:

1. Install Latest Official Image:
   • Download the latest Raspbian Buster image from the official Raspberry Pi website.
   • Format your Micro SD card using a tool like SDFormatter.
   • Use Win32DiskImager or Raspberry Pi Imager to burn the official image to the Micro SD card.
2. Connect Raspberry Pi:

   Insert the prepared Micro SD card into your Raspberry Pi. Connect a network cable (for internet access), a mouse, a keyboard, and a standard HDMI monitor. Connect the power supply to start the Raspberry Pi.

3. Install LCD Driver:
   • Access the Raspberry Pi Terminal (command line interface).
   • Execute the following commands to download and install the LCD driver:

     sudo rm -rf LCD-show
     git clone https://github.com/goodtft/LCD-show.git
     chmod -R 755 LCD-show
     cd LCD-show/
     sudo ./MHS35-show

   • After the driver installation completes, the system will restart. Disconnect the power, then connect the 3.5-inch screen to the Raspberry Pi. Reconnect power, and the screen should now be operational.

4. Operating Instructions

4.1 Display Switching

If you have installed the driver and wish to switch back to an HDMI monitor from the 3.5-inch screen, access the Raspberry Pi Terminal and run the following command:

cd LCD-show/
sudo ./LCD-hdmi

To switch back to the 3.5-inch LCD, you would typically run the `sudo ./MHS35-show` command again from the `LCD-show` directory.

4.2 Touch Functionality

The 3.5-inch display features resistive touch. Use the provided touch pen or a suitable stylus for precise interaction with the screen. Basic touch gestures are supported by the installed driver.

Image: The fully assembled CUQI 3.5-inch touchscreen display kit, including the Raspberry Pi 4 housed within its protective case, with the touchscreen mounted on top. A stylus is depicted interacting with the screen, highlighting its touch functionality.

5. Important Notices and Warnings

Please be aware of the following points:

• GPIO Pin Usage: After the screen is installed, the General Purpose Input/Output (GPIO) pins on the Raspberry Pi may not be accessible or usable for other purposes.
• Backlight Control: This display kit does not include a physical backlight ON/OFF key.
• Driver Installation Issues: Some users may encounter system crashes or a blank display after manual driver installation. If you are not familiar with Raspberry Pi system configuration, it is strongly recommended to use the pre-configured system image (Mode 1) for a smoother experience.
• System Compatibility: This display kit is primarily designed for Raspbian Buster and compatible Linux distributions (Ubuntu, Kali, RetroPie). It does not support other operating systems such as Windows.
• Optimal Viewing Angle: The best viewing angle for this display is vertical.

Image: This image outlines key product advantages, such as effective heat dissipation and smooth video playback, alongside important notices regarding GPIO pin usage, potential driver installation issues, system compatibility (not Windows), and optimal viewing angle.

6. Specifications

Detailed technical specifications for the CUQI 3.5-inch touchscreen display kit:

Image: A graphic detailing the technical specifications of the 3.5-inch touchscreen, including its size, SPI touch interface, resistive touch type, low power consumption, 480x320 resolution, and compatibility with Raspbian, Ubuntu, Kali, and RetroPie operating systems.

7. Troubleshooting

• Display Not Working After Driver Installation:

  If the screen remains blank or the system crashes after attempting manual driver installation (Mode 2), ensure that you have followed all steps precisely. Verify the correct Raspbian Buster image was used. If issues persist, it is highly recommended to use the pre-configured system image (Mode 1) as it includes pre-tested drivers.

• No Touch Response:

  Ensure the screen is firmly seated on the Raspberry Pi's GPIO pins. Recheck the driver installation. If using a custom OS, confirm driver compatibility.
• Fan Noise:

  While the fan is designed to be quiet, some noise may be present during operation. Ensure the fan is securely mounted and free from obstructions.

8. Maintenance

• Cleaning: Use a soft, dry, anti-static cloth to clean the screen and case. Avoid liquid cleaners directly on the screen.
• Storage: Store the device in a cool, dry place away from direct sunlight and extreme temperatures.
• Handling: Handle the device with care to avoid physical damage to the screen or internal components.

9. Warranty and Support

Specific warranty information for this product is not provided in the available documentation. For support inquiries, please refer to the retailer or manufacturer's official contact channels.