Is it possible to save calibration data of magnetometer to NVM in BMX160?

[odeng250won]

Dear All

I'm working with bmx160.

As I  Know, the calibration data for Accelerometer and gyro sensor  can be saved to NVM using command, but there is no explain for magnetometer.

If it is possible, let me know how to save calibration data of magnetometer.

Thanks.

[FAE_CA1]

Hi,

Thanks for your inquiry.

It is true that BMX160 accel and gyro calibration offset values can be saved in the registers, but now in the NVM. This means that when BMX160 is powered off, those calibration offset values will be lost.

It is not possible to save mag calibration offset values in either registers or NVM, because the mag BMM150 inside BMX160 doesn't have such feature. In addition the mag always needs to be calibrated before use if there is environment magnetic field change at the same location or the mag is moved to another location. Performing a few figure-8 motions in 3D space can calibrate the mag before using it for eCompass or 9DoF sensor fusion.

Thanks.

[odeng250won]

I understood there is no way to save magnetic data to NVM for BMX160.

I have one more question.

Is it possible to calibrate magnetometer without BSX library? 
If so, please let me know the way or reference document?

Thanks.

[FAE_CA1 · Accepted solution]

Hi,

The magnetometer inside BMX160 is BMM150. You can use our API at https://github.com/boschsensortec/BMI160_driver to configure BMM150 to work in normal mode at 25Hz sampling rate and then get BMM150 data in the unit of uT. You can then search Google for "magnetometer calibration" or "9DoF sensor fusion". You will find a lot of articles and open source sample codes for magnetometer calibration and sensor fusion without using BSX library.

Thanks.