LIS3MDL calibration issues

[bu]

I'm using a LIS3MDL magnetometer on my board, and I figured out how to calibrate it to account for distortions  caused by the board, and the procedure works. However, it seems that every time the same magnetometer is turned off and re-powered, the measurements received are different. I saw somewhere that the LIS3MDL will self calibrate at startup and I think this might be what causes the differences. Is there any way to disable this process, and if that isn't the issue, do you know what it might be?

[Federica Bossi · Accepted solution]

Hi @bu ,

The LIS3MDL does not perform an automatic hard‑iron “self‑calibration” at startup, so there’s nothing of that kind to disable. Any change you see after power‑cycling is usually due to:

• Different register configuration after each boot (FS range, ODR, operating mode, performance mode).
• Your own calibration not being re‑applied exactly the same way (or done at a different FS).

Ensure you always write the same configuration registers on startup, read them back to verify, then apply the same stored calibration parameters to the raw data each time.