How to Use ESP32-S3 1.75inch AMOLED Round : Examples, Pinouts, and Specs

The ESP32-S3 1.75inch AMOLED Round by WaveShare is a compact display module that combines a high-resolution 1.75-inch AMOLED screen with the powerful ESP32-S3 microcontroller. This module is designed for applications requiring vibrant graphics, low power consumption, and wireless connectivity. The ESP32-S3 provides dual-core processing, Wi-Fi, and Bluetooth capabilities, making it ideal for IoT, wearable devices, smart home systems, and portable displays.

• Smartwatches and wearable devices
• IoT dashboards and control panels
• Portable media players
• Smart home automation interfaces
• Educational and prototyping projects

The module features a standard pin header for easy integration. Below is the pinout:

1. Power Supply: Connect the VCC pin to a 3.3V power source and GND to ground.
2. SPI Communication: Connect the SPI pins (SCK, MOSI, MISO, CS) to the corresponding SPI pins on your microcontroller or development board.
3. Control Signals: Use the DC pin to toggle between data and command modes. The RST pin can be used to reset the display.
4. Backlight Control: The BL pin can be connected to a PWM-capable pin on your microcontroller to adjust the screen brightness.
5. Touch Panel (Optional): If your module includes a touch panel, connect the TP_INT pin to an interrupt-capable pin on your microcontroller.

• Ensure the power supply is stable and within the specified voltage range (3.3V).
• Use appropriate pull-up or pull-down resistors for SPI lines if required.
• Avoid prolonged exposure to static electricity to prevent damage to the AMOLED screen.
• If using the touch panel, debounce the interrupt signal in software to avoid false triggers.

Below is an example of how to interface the ESP32-S3 1.75inch AMOLED Round with an Arduino UNO using the SPI interface. Note that the ESP32-S3 is the onboard microcontroller, but this example demonstrates external control.

#include <SPI.h>

// Define SPI pins
#define CS_PIN 10    // Chip select pin
#define DC_PIN 9     // Data/Command pin
#define RST_PIN 8    // Reset pin
#define BL_PIN 6     // Backlight control pin (PWM)

// Function to initialize the display
void initDisplay() {
  pinMode(CS_PIN, OUTPUT);
  pinMode(DC_PIN, OUTPUT);
  pinMode(RST_PIN, OUTPUT);
  pinMode(BL_PIN, OUTPUT);

  // Reset the display
  digitalWrite(RST_PIN, LOW);
  delay(100);
  digitalWrite(RST_PIN, HIGH);
  delay(100);

  // Initialize SPI
  SPI.begin();
  digitalWrite(CS_PIN, HIGH); // Deselect the display
}

// Function to send a command to the display
void sendCommand(uint8_t cmd) {
  digitalWrite(CS_PIN, LOW);  // Select the display
  digitalWrite(DC_PIN, LOW);  // Command mode
  SPI.transfer(cmd);
  digitalWrite(CS_PIN, HIGH); // Deselect the display
}

// Function to send data to the display
void sendData(uint8_t data) {
  digitalWrite(CS_PIN, LOW);  // Select the display
  digitalWrite(DC_PIN, HIGH); // Data mode
  SPI.transfer(data);
  digitalWrite(CS_PIN, HIGH); // Deselect the display
}

void setup() {
  initDisplay();
  analogWrite(BL_PIN, 128); // Set backlight brightness (50%)
  
  // Example: Clear the screen with a command
  sendCommand(0x01); // Clear display command (example)
}

void loop() {
  // Add your display logic here
}

1. Display Not Turning On

   • Ensure the VCC and GND connections are secure and the power supply is 3.3V.
   • Check the RST pin; ensure it is not held low.

2. No Response from the Display

   • Verify the SPI connections and ensure the correct pins are used.
   • Check the CS, DC, and RST signals for proper operation.

3. Touch Panel Not Responding

   • Ensure the TP_INT pin is connected to an interrupt-capable pin on your microcontroller.
   • Verify that the touch panel is enabled in your software.

4. Flickering or Dim Display

   • Check the BL pin connection and ensure the PWM signal is stable.
   • Verify that the power supply can provide sufficient current.

• Use a logic analyzer or oscilloscope to debug SPI communication if the display is unresponsive.
• Refer to the WaveShare datasheet for detailed initialization sequences and commands.
• If using the ESP32-S3 onboard microcontroller, leverage its built-in libraries for SPI and display control to simplify development.