How to Use ESP-32 DEVKIT-V1 with Expansion Board: Examples, Pinouts, and Specs

The ESP-32 DEVKIT-V1 with Expansion Board, manufactured by Espressif, is a versatile development board designed for IoT (Internet of Things) applications. It features the powerful ESP32 chip, which integrates Wi-Fi and Bluetooth capabilities, making it ideal for wireless communication projects. The expansion board enhances the functionality of the ESP32 by providing additional GPIO pins, sensor interfaces, and prototyping-friendly features.

• IoT devices and smart home automation
• Wireless sensor networks
• Wearable technology
• Robotics and automation systems
• Prototyping and educational projects

The ESP-32 DEVKIT-V1 with Expansion Board provides a variety of pins for interfacing with peripherals. Below is the pinout description:

Note: The exact pin availability and functionality may vary depending on the specific expansion board used.

1. Powering the Board:

   • Connect the ESP-32 DEVKIT-V1 to your computer using a micro-USB cable. This will power the board and allow programming.
   • Alternatively, supply 5V to the VIN pin and connect GND to the ground of your power source.

2. Programming the Board:

   • Install the Arduino IDE and add the ESP32 board support package via the Board Manager.
   • Select "ESP32 Dev Module" from the Tools > Board menu.
   • Connect the board to your computer and select the appropriate COM port.

3. Connecting Peripherals:

   • Use the GPIO pins to connect sensors, actuators, or other peripherals.
   • Ensure that the voltage levels of connected devices are compatible with the 3.3V logic of the ESP32.

4. Uploading Code:

   • Write your code in the Arduino IDE or another supported environment.
   • Click the upload button to flash the code to the ESP32.

• Voltage Levels: The ESP32 operates at 3.3V logic. Avoid connecting 5V signals directly to GPIO pins to prevent damage.
• Boot Mode: Ensure GPIO0 is pulled low during boot to enter programming mode.
• Power Supply: Use a stable power source to avoid unexpected resets or instability.
• Wi-Fi Antenna: Avoid placing metal objects near the onboard antenna to ensure optimal wireless performance.

Below is an example of using the ESP-32 DEVKIT-V1 to read data from a DHT11 temperature and humidity sensor and send it to a serial monitor:

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

// Define DHT sensor type and pin
#define DHTPIN 4       // GPIO4 is connected to the DHT sensor
#define DHTTYPE DHT11  // DHT11 sensor type

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);  // Initialize serial communication
  dht.begin();           // Initialize the DHT sensor
  Serial.println("DHT11 Sensor Test");
}

void loop() {
  delay(2000);  // Wait 2 seconds between readings

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

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

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

Note: Ensure the DHT sensor is connected to GPIO4 and powered with 3.3V or 5V.

1. Board Not Detected by Computer:

   • Ensure the USB cable is functional and supports data transfer.
   • Install the correct USB-to-serial driver for the ESP32.

2. Code Upload Fails:

   • Check that the correct COM port and board type are selected in the Arduino IDE.
   • Hold the "BOOT" button on the ESP32 while uploading the code.

3. Wi-Fi Connection Issues:

   • Verify the SSID and password in your code.
   • Ensure the Wi-Fi network is within range and operational.

4. Unstable Operation:

   • Use a stable power supply with sufficient current (at least 500mA).
   • Avoid excessive load on GPIO pins.

• Reset the Board: Press the "EN" button to reset the ESP32 if it becomes unresponsive.
• Check Connections: Verify all wiring and connections to ensure proper functionality.
• 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 ESP-32 DEVKIT-V1 with Expansion Board for a wide range of IoT and prototyping applications.