How to Use Adafruit ESP32-S3 Reverse TFT Feather: Examples, Pinouts, and Specs

The Adafruit ESP32-S3 Reverse TFT Feather (Part ID: 5691) is a compact and versatile development board built around the ESP32-S3 microcontroller. It is designed for low-power IoT applications and features integrated Wi-Fi and Bluetooth connectivity. The standout feature of this board is its reverse-mounted 240x135 pixel TFT display, which provides a convenient way to display visual output directly on the board.

This board is ideal for projects requiring wireless communication, graphical interfaces, or low-power operation. It is particularly well-suited for IoT devices, wearable electronics, and portable data visualization tools.

• Microcontroller: ESP32-S3 dual-core Xtensa LX7
• Clock Speed: Up to 240 MHz
• Flash Memory: 8 MB
• PSRAM: 2 MB
• Display: 1.14" 240x135 pixel TFT (ST7789 driver)
• Connectivity: Wi-Fi (802.11 b/g/n) and Bluetooth 5.0 LE
• Power Supply: 3.3V logic, USB-C for power and programming
• Battery Support: JST-PH connector for LiPo batteries (with charging circuit)
• GPIO Pins: 21 GPIO pins, including ADC, DAC, I2C, SPI, UART, and PWM
• Dimensions: 51mm x 23mm x 8mm (2" x 0.9" x 0.3")
• Weight: 5.5g

The Adafruit ESP32-S3 Reverse TFT Feather has a standard Feather pinout. Below is a table summarizing the key pins and their functions:

1. Powering the Board:

   • Connect the board to a USB-C cable for power and programming.
   • Alternatively, connect a LiPo battery to the JST-PH connector for portable operation.

2. Programming the Board:

   • Install the latest version of the Arduino IDE.
   • Add the ESP32 board support package via the Arduino Boards Manager.
   • Select "Adafruit ESP32-S3 Reverse TFT Feather" as the target board.

3. Connecting Peripherals:

   • Use the GPIO pins to connect sensors, actuators, or other peripherals.
   • For I2C devices, connect to the SDA and SCL pins.
   • For SPI devices, use the MOSI, MISO, and SCK pins.

4. Using the TFT Display:

   • The TFT display is pre-wired to the ESP32-S3. Use the Adafruit GFX and Adafruit ST7789 libraries to control the display.

• Voltage Levels: Ensure all connected peripherals operate at 3.3V logic levels to avoid damaging the board.
• Battery Charging: If using a LiPo battery, the onboard charging circuit will automatically charge the battery when connected to USB power.
• Pin Multiplexing: Some GPIO pins may have multiple functions. Refer to the ESP32-S3 datasheet for details.
• Heat Management: Avoid prolonged operation at high clock speeds to prevent overheating.

Below is an example sketch to display text on the TFT screen:

#include <Adafruit_GFX.h>       // Core graphics library
#include <Adafruit_ST7789.h>    // Driver for the TFT display
#include <SPI.h>

// Define TFT display pins
#define TFT_CS        10  // Chip select pin
#define TFT_RST       9   // Reset pin
#define TFT_DC        8   // Data/command pin

// Initialize the TFT display
Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_RST);

void setup() {
  // Initialize serial communication
  Serial.begin(115200);
  Serial.println("Initializing TFT...");

  // Initialize the TFT display
  tft.init(240, 135);  // Initialize with screen dimensions
  tft.setRotation(1);  // Set screen rotation
  tft.fillScreen(ST77XX_BLACK);  // Clear the screen

  // Display text
  tft.setTextColor(ST77XX_WHITE);
  tft.setTextSize(2);
  tft.setCursor(10, 10);
  tft.println("Hello, ESP32-S3!");
}

void loop() {
  // Nothing to do here
}

1. Board Not Detected by Arduino IDE:

   • Ensure the correct USB driver is installed for the ESP32-S3.
   • Check that the correct board and port are selected in the Arduino IDE.

2. TFT Display Not Working:

   • Verify the Adafruit GFX and Adafruit ST7789 libraries are installed.
   • Ensure the correct pin definitions are used in your code.

3. Wi-Fi or Bluetooth Not Connecting:

   • Double-check your network credentials or Bluetooth pairing settings.
   • Ensure the ESP32-S3 firmware is up to date.

4. Overheating:

   • Reduce the clock speed or limit the duration of high-power operations.

• Can I use 5V peripherals with this board?
  No, the board operates at 3.3V logic levels. Use a level shifter for 5V peripherals.

• What is the maximum current draw for the board?
  The maximum current draw depends on the peripherals connected, but the ESP32-S3 itself can draw up to 500mA under heavy load.

• Can I use the board without a battery?
  Yes, the board can be powered solely via USB-C.

• Is the TFT display backlight adjustable?
  Yes, the backlight can be controlled via the TFT_BACKLIGHT pin using PWM.

This concludes the documentation for the Adafruit ESP32-S3 Reverse TFT Feather.