How to Use 24GHz mmWave Sensor for XIAO : Examples, Pinouts, and Specs

The 24GHz mmWave Sensor for XIAO by Seeed Studio is a compact and highly efficient sensor designed for motion detection and distance measurement. Operating at a frequency of 24GHz, this sensor leverages millimeter-wave technology to provide accurate and reliable data in a variety of environments. Its small form factor makes it an ideal choice for integration with Seeed Studio's XIAO microcontroller platforms, enabling developers to create innovative IoT, robotics, and automation projects.

• Motion detection for smart home automation
• Distance measurement in robotics and drones
• Presence detection in security systems
• Gesture recognition for touchless interfaces
• Industrial automation and monitoring

The following table outlines the key technical details of the 24GHz mmWave Sensor for XIAO:

The sensor features a 4-pin interface for easy connection to the XIAO microcontroller. The pinout is as follows:

1. Power the Sensor: Connect the VCC pin to a 3.3V or 5V power source and the GND pin to ground.
2. Connect to XIAO: Use the TX and RX pins to establish a UART connection with the XIAO microcontroller. Ensure that the TX pin of the sensor is connected to the RX pin of the XIAO, and vice versa.
3. Load the Code: Upload the appropriate code to the XIAO microcontroller to initialize the sensor and process the data.

• Power Supply: Ensure a stable power supply to avoid fluctuations that may affect sensor performance.
• Placement: Mount the sensor in a location free from obstructions to maximize its detection range and accuracy.
• UART Configuration: Verify that the UART baud rate is set to 115200 bps for proper communication.
• Environmental Factors: The sensor is designed to operate in a wide temperature range, but extreme environmental conditions (e.g., heavy rain or dense fog) may impact its performance.

Below is an example code snippet to interface the 24GHz mmWave Sensor with a XIAO microcontroller:

// Include the SoftwareSerial library for UART communication
#include <SoftwareSerial.h>

// Define the RX and TX pins for the sensor
#define SENSOR_RX 6  // Connect to the TX pin of the sensor
#define SENSOR_TX 7  // Connect to the RX pin of the sensor

// Create a SoftwareSerial object for the sensor
SoftwareSerial mmWaveSerial(SENSOR_RX, SENSOR_TX);

void setup() {
  // Initialize the serial communication for debugging
  Serial.begin(115200);
  // Initialize the sensor's UART communication
  mmWaveSerial.begin(115200);

  Serial.println("24GHz mmWave Sensor Initialized");
}

void loop() {
  // Check if data is available from the sensor
  if (mmWaveSerial.available()) {
    // Read and print the data from the sensor
    String sensorData = mmWaveSerial.readString();
    Serial.println("Sensor Data: " + sensorData);
  }

  delay(100); // Add a small delay to avoid overwhelming the serial buffer
}

1. No Data Output from the Sensor

   • Cause: Incorrect UART connection or baud rate mismatch.
   • Solution: Double-check the wiring and ensure the baud rate is set to 115200 bps.

2. Inconsistent Readings

   • Cause: Environmental interference or unstable power supply.
   • Solution: Ensure the sensor is placed in a clear area and use a stable power source.

3. Sensor Not Detected by XIAO

   • Cause: Incorrect pin connections or faulty sensor.
   • Solution: Verify the pin connections and test the sensor with another microcontroller.

• Q: Can the sensor detect objects through walls or glass?
  A: The sensor can detect objects through certain materials, but dense or metallic barriers may block the signal.

• Q: Is the sensor compatible with other microcontrollers?
  A: Yes, the sensor can be used with other microcontrollers that support UART communication.

• Q: How can I extend the detection range?
  A: The detection range is hardware-limited to 10m. For longer ranges, consider using a different sensor model.

This documentation provides a comprehensive guide to using the 24GHz mmWave Sensor for XIAO. For further assistance, refer to the official Seeed Studio resources or community forums.