PX4+QGC internal/external magnetometer calibration and orientation

PX4 Autopilot
1

As I understand, Pixracer has 2 magnetometers on board and I am connecting one more externally (with M8N GPS).

I did not find any individual mag settings in QGC mag calibration screen. From reading the web I understand there are orientation and calibration parameters in QGC Parameters section. Is it where I set the orientation for different magnetometers before calibration? Not sure which mag ID is for the external mag…
Some info might be too old. Is it correct that there is a primary magnetometer and it is usually the external one (automatically selected as primary)?
Does calibration procedure work with all magnetometers simultaneously?
My Pixracer board does not need any rotation offset, but external mag might need ROLL_180, not sure yet. If it does, do I need to set it in PARAMETERS before running calibration? If I don’t set it and my mag orientation is different from Pixracer controller orientation, will calibration procedure fail ?

Thanks,

Mikhail

2

Just do a compass cal, and after it completes you will be prompted to set the external compass orientation. All compasses are calibration at the same ime.

3

Thanks! I just noticed that “Set Orientation” button in Sensor Calibration. For some reason I did not see it yesterday.
I get it now. Calibration procedure does not use rotation parameter and it makes sense :slight_smile:
Compass seems to work fine now with ROTATION_NONE. It was not clear from BN-880 GPS description where the top/bottom of the compass chip is. Looks like the top is actually where GPS antenna is (i.e. no software rotation needed).

4

You won’t see Set Orientation until after you calibrate the very first time. Before that QGC has no idea whether you have any external compasses which need possible orientation.