How to Use Esp32 Feather v2: Examples, Pinouts, and Specs

The ESP32 Feather v2 by Adafruit is a compact and versatile microcontroller board designed for IoT (Internet of Things) applications. It features a powerful dual-core ESP32 processor with integrated Wi-Fi and Bluetooth capabilities, making it ideal for wireless communication and smart device projects. The board is part of Adafruit's Feather ecosystem, ensuring compatibility with a wide range of FeatherWing add-ons for extended functionality.

• IoT devices and smart home automation
• Wireless sensor networks
• Wearable technology
• Robotics and automation
• Prototyping and development of connected devices
• Data logging and remote monitoring

The ESP32 Feather v2 is packed with features to support a variety of applications. Below are its key technical details:

The ESP32 Feather v2 has a rich set of GPIO pins, each with specific functions. Below is the pinout description:

The ESP32 Feather v2 is easy to use and highly adaptable for various projects. Below are the steps and best practices for using the board:

1. Powering the Board:
   • Connect the board to a USB-C cable for power and programming.
   • Alternatively, connect a 3.7V LiPo battery to the JST connector for portable applications.
2. Programming:
   • Install the latest version of the Arduino IDE.
   • Add the ESP32 board support package to the Arduino IDE by following the instructions on the ESP32 Arduino GitHub page.
   • Select "Adafruit ESP32 Feather" as the board in the Arduino IDE.
3. Connecting Peripherals:
   • Use the GPIO pins to connect sensors, actuators, or other modules.
   • For I2C devices, connect to GPIO21 (SDA) and GPIO22 (SCL).
   • For SPI devices, use the designated SPI pins (MOSI, MISO, SCK, and CS).

• 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.
• Wi-Fi and Bluetooth: Avoid placing the board in metal enclosures, as this can interfere with wireless communication.
• Boot Mode: To enter bootloader mode, hold down the BOOT button while pressing the RESET button.

Below is an example of how to use the ESP32 Feather v2 to read data from a DHT11 temperature and humidity sensor and send it over Wi-Fi:

#include <WiFi.h>
#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <DHT_U.h>

// Replace with your network credentials
const char* ssid = "Your_SSID";
const char* password = "Your_PASSWORD";

// DHT sensor configuration
#define DHTPIN 4       // GPIO pin connected to the DHT sensor
#define DHTTYPE DHT11  // DHT11 or DHT22

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);
  delay(10);

  // Initialize DHT sensor
  dht.begin();
  Serial.println("DHT sensor initialized.");

  // Connect to Wi-Fi
  Serial.print("Connecting to Wi-Fi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWi-Fi connected.");
}

void loop() {
  // Read temperature and humidity
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();

  // Check if readings are valid
  if (isnan(temperature) || isnan(humidity)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Print readings to Serial Monitor
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  delay(2000); // Wait 2 seconds before next reading
}

1. Board Not Detected by Arduino IDE:
   • Ensure the correct USB driver is installed for the ESP32.
   • Check that the correct board and port are selected in the Arduino IDE.
2. Wi-Fi Connection Fails:
   • Verify the SSID and password are correct.
   • Ensure the Wi-Fi network is within range and not overloaded.
3. Sensor Readings Are Incorrect:
   • Check the wiring and ensure the sensor is compatible with 3.3V logic.
   • Verify the sensor library is correctly installed.

• Reset the Board: Press the RESET button to restart the microcontroller.
• Check Power Supply: Ensure the board is receiving sufficient power, especially when using peripherals.
• Update Firmware: Use the latest ESP32 board support package to ensure compatibility and bug fixes.
• Debugging: Use the Serial Monitor in the Arduino IDE to print debug messages and identify issues.

By following this documentation, users can effectively utilize the ESP32 Feather v2 for a wide range of IoT and embedded applications.