Magic Wand example Issue: No data from IMU

[wundabar0]

Hey,
I'm using the XIAO MG24 Sense running the example project magic_wand_imu_capture on software versions Silabs Arduino boards v3.0.0 and stm32duino LSM6DSOX library v2.3.4.
My issue is that I don't see any output on the serial after "aX,aY,aZ,gX,gY,gZ" from setup(). I did some debugging and I see that the accel and gyro flags are not setting nor are the accel or gyro values changing when read directly in a simple loop. I also see the behavior on the example project magic_wand.
Note that the other example, ble_hid_mouse_xiao_mg24 works just fine - the mouse moves with the movement of the board. This example uses a different library for reading the IMU, namely, Seeed Arduino LSM6DS3 v2.0.4.
Am I missing something?

[Leonardo Cavagnis (leonardocavagnis)]

Hey,
XIAO MG24 Sense board uses LSM6DS3TR-C imu sensor.
Magic wand example works with LSM6DSOX imu sensor. You should adapt the example on your IMU sensor using the correct library (LSM6DS3 library as in the example ble_hid_mouse_xiao_mg24)

[wundabar0]

Thanks Leonardo,

I've included here a barebones IMU acceleration + gyro CSV data logger sketch that anyone can use to capture data to build ML models on the MG24 Sense.

/*
  Project: XIAO MG24 Sense IMU CSV Logger
  Author:  Brendan Henrich
  Date:    2025-08-26

  Description:
    This sketch initializes the Seeed Studio LSM6DS3 IMU on the XIAO MG24 Sense board,
    continuously reads accelerometer and gyroscope data, and outputs it to the 
    serial port in CSV format for easy logging or post-processing.

    Libraries Used:
      - Seeed Arduino LSM6DS3: https://github.com/Seeed-Studio/Seeed_Arduino_LSM6DS3

    Compatible Board:
      - Seeed Studio XIAO MG24 Sense (EFR32MG24)
      - Make sure Tools > Protocol Stack = "BLE (Silabs)" (for compatibility)

    CSV Output Format:
      timestamp_ms,accel_x_g,accel_y_g,accel_z_g,gyro_x_dps,gyro_y_dps,gyro_z_dps

    Example Output:
      1234,0.01,-0.02,1.00,0.05,-0.01,0.02
*/

#include <Wire.h>
#include "LSM6DS3.h"

// -----------------------------------------------------------------------------
// IMU Setup
// -----------------------------------------------------------------------------
LSM6DS3 myIMU(I2C_MODE, 0x6A);  // I2C address 0x6A for LSM6DS3 on XIAO MG24

// -----------------------------------------------------------------------------
// Sampling Settings
// -----------------------------------------------------------------------------
#define IMU_READ_INTERVAL_MS 50  // Read IMU every 50ms (~20Hz)

// -----------------------------------------------------------------------------
// Setup Function
// -----------------------------------------------------------------------------
void setup() {
  // Start serial communication for CSV logging
  Serial.begin(115200);
  while (!Serial) {
    ; // Wait for Serial to initialize (important when using USB CDC)
  }

  Serial.println("timestamp_ms,accel_x_g,accel_y_g,accel_z_g,gyro_x_dps,gyro_y_dps,gyro_z_dps");

  // Initialize IMU
  if (myIMU.begin() != 0) {
    Serial.println("IMU initialization failed! Check wiring or I2C address.");
    while (1);
  }

  Serial.println("IMU initialized successfully.");
}

// -----------------------------------------------------------------------------
// Loop Function
// -----------------------------------------------------------------------------
void loop() {
  static uint32_t last_read = 0;
  uint32_t now = millis();

  // Check if it's time to read the IMU
  if (now - last_read >= IMU_READ_INTERVAL_MS) {
    last_read = now;

    // -------------------------------------------------------------------------
    // Read Accelerometer Data (in g)
    // -------------------------------------------------------------------------
    float accelX = myIMU.readFloatAccelX();
    float accelY = myIMU.readFloatAccelY();
    float accelZ = myIMU.readFloatAccelZ();

    // -------------------------------------------------------------------------
    // Read Gyroscope Data (in degrees/sec)
    // -------------------------------------------------------------------------
    float gyroX = myIMU.readFloatGyroX();
    float gyroY = myIMU.readFloatGyroY();
    float gyroZ = myIMU.readFloatGyroZ();

    // -------------------------------------------------------------------------
    // Output in CSV Format
    // -------------------------------------------------------------------------
    Serial.print(now);      Serial.print(",");
    Serial.print(accelX);   Serial.print(",");
    Serial.print(accelY);   Serial.print(",");
    Serial.print(accelZ);   Serial.print(",");
    Serial.print(gyroX);    Serial.print(",");
    Serial.print(gyroY);    Serial.print(",");
    Serial.println(gyroZ);
  }
}