BMM350 Calibration Guidance

[bbooher]

I'm developing an application that uses the BMM350. The product is a custom board, using the nRF5340 SOC running Zephyr RTOS. We've developed an out-of-tree driver to support the BMM350 (wrapping the BMM350API) and verified we can read data - so all good there. I'm looking for calibration documentation or guidance during run-time, as it's not apparent from the documentation I've seen. A few questions:

- can the compensation values be overwritten? If so, is that the recommended method for run-time calibration?

- should instead, the SOC (or off-board application, since I have BLE connectivity) be responsible for the calibration algorithm and merely apply an offset and bias at collection time? If so, is there recommended guidance for this approach?

[BSTRobin]

Hi bbooher,

Thanks for your inquiry.
Normally magnetic sensor only output sensor data, calibration algorithms need to be running on the host side.
We have mag calibration algorithms running on the BHIxxx series of products(https://www.bosch-sensortec.com/products/smart-sensor-systems/programmable-and-ai-sensor-systems/), and users can directly use the calibration algorithms on this series of products, but we have not disclosed the details of its algorithm implementation.

[bbooher]

Thanks for the quick response. That link appears to only be IMU (not magnetometer) products. Do you mean another product line, instead? Or do those products have an option to pair with a magnetometer like the BMM350?

[FAE_CA1]

Hi,

Please see the attached "How to play with BHI360 shuttle board 3.0 v1.pdf". BHI360 smart sensor has Bosch BSX sensor fusion algorithm running inside that can automatically calibrate BMM350 when BMM350 is connected to BHI360.

Thanks.