How to Use ESP32D on Goouuu Expansion Board: Examples, Pinouts, and Specs

The ESP32D on the Goouuu Expansion Board is a versatile development platform featuring the ESP32D microcontroller, manufactured by Espressif. This board is specifically designed for Internet of Things (IoT) applications, offering built-in Wi-Fi and Bluetooth connectivity. It also provides a wide range of GPIO pins, making it suitable for prototyping and developing smart devices, home automation systems, and other connected projects.

• IoT devices and smart home systems
• Wireless sensor networks
• Wearable technology
• Robotics and automation
• Data logging and remote monitoring
• Bluetooth-enabled applications

• Microcontroller: ESP32D (Espressif)
• Processor: Dual-core Xtensa® 32-bit LX6 CPU
• Clock Speed: Up to 240 MHz
• Flash Memory: 4 MB
• SRAM: 520 KB
• Connectivity:
  • Wi-Fi: 802.11 b/g/n
  • Bluetooth: v4.2 BR/EDR and BLE
• Operating Voltage: 3.3V
• Input Voltage (via USB): 5V
• GPIO Pins: 30+ (including ADC, DAC, PWM, I2C, SPI, UART)
• Power Consumption: Ultra-low power consumption in deep sleep mode (~10 µA)
• Dimensions: 58mm x 25mm (approx.)

The Goouuu Expansion Board provides easy access to the ESP32D's pins. Below is the pinout description:

Note: Some GPIO pins have specific functions (e.g., ADC, DAC, PWM). Refer to the ESP32D datasheet for detailed pin capabilities.

1. Powering the Board:

   • Connect the board to a computer or USB power source using a micro-USB cable.
   • Alternatively, supply 5V to the VIN pin and connect GND to the ground.

2. Programming the ESP32D:

   • Install the Arduino IDE and add the ESP32 board support package.
   • 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 external components operate at 3.3V logic levels to avoid damaging the ESP32D.

4. Uploading Code:

   • Write your code in the Arduino IDE or another compatible environment.
   • Click the "Upload" button to flash the code to the ESP32D.

• Voltage Levels: The ESP32D operates at 3.3V. Avoid applying 5V directly to GPIO pins.
• Boot Mode: To enter bootloader mode, hold the "BOOT" button while pressing the "EN" (reset) button.
• Power Supply: Use a stable power source to prevent unexpected resets or malfunctions.
• Wi-Fi and Bluetooth: Avoid placing the board near metal objects or sources of interference to ensure reliable wireless communication.

Below is an example of how to use the ESP32D to read a sensor value and send it over Wi-Fi:

#include <WiFi.h>

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

void setup() {
  Serial.begin(115200); // Initialize serial communication at 115200 baud
  WiFi.begin(ssid, password); // Connect to Wi-Fi network

  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to Wi-Fi...");
  }

  Serial.println("Connected to Wi-Fi");
}

void loop() {
  // Example: Read a sensor value (e.g., analog pin A0)
  int sensorValue = analogRead(34); // GPIO34 is an ADC pin
  Serial.print("Sensor Value: ");
  Serial.println(sensorValue);

  delay(1000); // Wait for 1 second before reading again
}

Note: Replace Your_SSID and Your_PASSWORD with your Wi-Fi network credentials.

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 ESP32D.

2. Code Upload Fails:

   • Check the selected COM port in the Arduino IDE.
   • Hold the "BOOT" button while uploading the code.

3. Wi-Fi Connection Issues:

   • Verify the SSID and password in your code.
   • Ensure the router is within range and not blocking the ESP32D.

4. Unexpected Resets:

   • Check the power supply for stability.
   • Avoid connecting high-current devices directly to the GPIO pins.

• Q: Can I power the board with a battery?

  • A: Yes, you can use a 3.7V LiPo battery connected to the 3V3 pin or a 5V source to the VIN pin.

• Q: How do I use Bluetooth on the ESP32D?

  • A: Use the BluetoothSerial library in the Arduino IDE to implement Bluetooth communication.

• Q: Can I use the ESP32D with other IDEs?

  • A: Yes, the ESP32D is compatible with platforms like PlatformIO and Espressif's IDF.

By following this documentation, you can effectively utilize the ESP32D on the Goouuu Expansion Board for your IoT and embedded projects.