How to Use Seeed Studio XIAO nRF52840 Plus: Examples, Pinouts, and Specs

The Seeed Studio XIAO nRF52840 Plus is a compact and powerful microcontroller board built around the Nordic nRF52840 chip. It is designed for low-power wireless applications and features Bluetooth 5.0 support, USB-C connectivity, and a variety of GPIO pins. Its small form factor and robust capabilities make it ideal for IoT, wearable devices, and other wireless communication projects.

• Bluetooth Low Energy (BLE) applications
• IoT devices and smart home systems
• Wearable technology
• Wireless sensors and data loggers
• Prototyping for low-power wireless communication

1. Powering the Board: Connect the board to a USB-C cable for power and programming. Alternatively, you can supply 3.3V to the 3V3 pin.
2. Programming: Use the Arduino IDE or other compatible development environments to program the board. Select "Seeed XIAO nRF52840" as the board in the IDE.
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 board.
4. Wireless Communication: Utilize the built-in Bluetooth 5.0 capabilities for wireless communication. Libraries such as Adafruit Bluefruit can simplify BLE development.

• Voltage Levels: Ensure all connected peripherals operate at 3.3V logic levels to avoid damaging the board.
• Heat Management: While the board is efficient, avoid prolonged high-current operations to prevent overheating.
• Firmware Updates: Regularly check for firmware updates to ensure compatibility and access to the latest features.
• Pin Usage: Avoid using the same pin for multiple functions simultaneously to prevent conflicts.

Below is an example of using the Seeed Studio XIAO nRF52840 Plus to blink an LED connected to pin D0.

// Define the pin for the LED
const int ledPin = D0;

void setup() {
  // Set the LED pin as an output
  pinMode(ledPin, OUTPUT);
}

void loop() {
  // Turn the LED on
  digitalWrite(ledPin, HIGH);
  delay(1000); // Wait for 1 second

  // Turn the LED off
  digitalWrite(ledPin, LOW);
  delay(1000); // Wait for 1 second
}

1. Board Not Recognized by Computer:

   • Ensure the USB-C cable is a data cable, not just a charging cable.
   • Check that the correct board and port are selected in the Arduino IDE.

2. Program Upload Fails:

   • Double-check the board selection in the IDE.
   • Press the reset button twice to enter bootloader mode and try uploading again.

3. Bluetooth Not Working:

   • Verify that the BLE library is correctly installed and initialized in your code.
   • Ensure the device is within range and not obstructed by physical barriers.

4. Overheating:

   • Reduce the current draw of connected peripherals.
   • Ensure proper ventilation around the board.

Q: Can I power the board with a battery?
A: Yes, you can power the board using a 3.7V LiPo battery connected to the 3V3 and GND pins.

Q: Does the board support USB OTG?
A: No, the USB-C port is primarily for programming and power.

Q: Can I use this board for Zigbee applications?
A: Yes, the nRF52840 chip supports Zigbee, but you will need to use appropriate libraries and configurations.

Q: Is the board compatible with CircuitPython?
A: Yes, the Seeed Studio XIAO nRF52840 Plus supports CircuitPython, making it versatile for Python-based development.