The GY-9255 sensor uses MPU-9255 chip which is a 9-axis sensor which packages the accelerometer, gyroscope, magnetometer together each provides data for x, y and z axes.  Other than the three mentioned sensors, it also has other features like Pedometer, Motion and Tap detection, and Temperature. It’s really sensitive low field magnetic sensor.  MPU-9255 is also designed to interface with multiple non-inertial digital sensors, such as pressure sensors, on its auxiliary I2C port and it guaranteeing optimal motion performance for users.

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