uint64 timestamp            # time since system start (microseconds)

uint64 timestamp_sample     # the timestamp of the raw data (microseconds)

uint32 device_id            # unique device ID for the selected magnetometer

float32[3] magnetometer_ga  # Magnetic field in NED body frame, in Gauss

uint8 calibration_count     # Calibration changed counter. Monotonically increases whenever calibration changes.