How to Use ESP32-S3-Touch-LCD-3.5B: Examples, Pinouts, and Specs

The ESP32-S3-Touch-LCD-3.5B is a versatile 3.5-inch touchscreen display module developed by Waveshare. It is powered by the ESP32-S3 microcontroller, which features dual-core Xtensa LX7 processors, integrated Wi-Fi, and Bluetooth 5.0 connectivity. This module is designed for interactive applications, IoT projects, and smart device interfaces, offering a seamless combination of display and processing capabilities.

• Smart home control panels
• IoT dashboards and monitoring systems
• Industrial automation interfaces
• Educational and prototyping projects
• Portable devices with touch-based user interfaces

The ESP32-S3-Touch-LCD-3.5B features a GPIO header for external connections. Below is the pinout description:

1. Powering the Module:

   • Connect a 5V power source to the USB-C port or use an external 5V supply via the GPIO header.
   • Ensure the power supply can provide sufficient current (at least 500 mA).

2. Connecting to External Devices:

   • Use the GPIO pins to interface with sensors, actuators, or other peripherals.
   • For SPI communication, connect the SCK, MISO, and MOSI pins to the corresponding pins on the external device.

3. Programming the ESP32-S3:

   • Install the Arduino IDE or ESP-IDF (Espressif IoT Development Framework).
   • Select the ESP32-S3 board in the development environment.
   • Connect the module to your computer via USB-C and upload your code.

4. Touchscreen Usage:

   • The capacitive touchscreen can be used to detect touch inputs. Libraries such as TFT_eSPI or LVGL (Light and Versatile Graphics Library) can be used to create graphical interfaces.

• Power Supply: Always use a stable 5V power source to avoid damage to the module.
• GPIO Voltage Levels: The GPIO pins operate at 3.3V logic levels. Avoid connecting 5V signals directly to the GPIO pins.
• Heat Management: If the module is used in high-performance applications, ensure proper ventilation to prevent overheating.
• Firmware Updates: Regularly update the ESP32-S3 firmware to ensure compatibility with the latest libraries and features.

Below is an example of how to use the ESP32-S3-Touch-LCD-3.5B with the Arduino IDE to display text on the screen:

#include <TFT_eSPI.h> // Include the TFT_eSPI library

TFT_eSPI tft = TFT_eSPI(); // Create an instance of the TFT_eSPI class

void setup() {
  tft.init(); // Initialize the display
  tft.setRotation(1); // Set the display orientation (0-3)
  tft.fillScreen(TFT_BLACK); // Clear the screen with black color

  // Display a message on the screen
  tft.setTextColor(TFT_WHITE, TFT_BLACK); // Set text color and background
  tft.setTextSize(2); // Set text size
  tft.setCursor(10, 10); // Set cursor position
  tft.println("Hello, ESP32-S3!"); // Print text to the screen
}

void loop() {
  // Add your code here for interactive functionality
}

1. The module does not power on:

   • Ensure the USB-C cable is properly connected and the power source is functional.
   • Check the power supply voltage and current ratings.

2. Touchscreen is unresponsive:

   • Verify that the touchscreen library is correctly installed and initialized.
   • Ensure the SPI connections are secure and configured correctly in the code.

3. Wi-Fi or Bluetooth is not working:

   • Check the firmware version and update if necessary.
   • Ensure the correct Wi-Fi credentials are provided in the code.

4. Display shows incorrect or no output:

   • Verify the display initialization code and ensure the correct library is used.
   • Check the SPI connections and ensure the pins are correctly assigned in the code.

• Can I power the module with a battery?
  Yes, you can use a 3.7V LiPo battery with a suitable voltage regulator to provide 5V input.

• What is the maximum touch input resolution?
  The touchscreen supports a resolution of 480 x 320 pixels, matching the display resolution.

• Is the module compatible with other development boards?
  Yes, the module can be used with other boards like Raspberry Pi or STM32, provided the SPI interface is configured correctly.

• Can I use the module outdoors?
  The module is not weatherproof. For outdoor use, ensure it is enclosed in a protective case.