Here4 Bad Compass?


I have 2x Here4 units and looks like one of them has bad compass. I thought it was bad setup this is why i started this thread: Here4 Compass DevID

but after switching to the other unit i realized it is not the param setup.

Comparing the here4 params on both working and not working the only diff is that the unit that is not work has “CAN_FDBAUDRATE,8000000” and the working unit don’t have this one at all.

I guess it is not related since it also have “CAN_FDMODE,0” but correct me if wrong here…

It is loaded with latest on both Here4 and Ubx


Any Ideas what can i do?

@guyzoler please set FORMAT_VERSION 0 on Here4 modules and retry. To verify id Compass data is being published, Goto DroneCAN tab in Setup, can click Inspector. Check if you see MagneticFieldStrength message show up. Also make sure you calibrate Compass after swapping Here4 modules.


Saw this one too late and the bad unit was already shipped to IRLOCK.

We’ll see what they find.

Hi Sid,
We have the Here4 now. Our tech couldn’t get the MagneticFieldStrength to appear (see image). He tried the FORMAT_VERSION 0 on the Here4.


@Thomas thanks! Can you please RMA this module. Mark it as failing Compass.

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I’m having the same issue with my here4

Please send a screenshot of the Inspector screen of the Here4 (as Sid has advised above, after setting FORMAT_VERSION 0 on the Here4).

As soon as I get home this evening I’ll get it done! Appreciate it!

This is not exhibiting the compass issue. Your mag is showing up as expected. (see MagneticFieldStrength in Inspector)

Ok… what do you need me to do? I also updated the firmware on the here4 and I flew it and was auto tuning and everything was going good for about 4 mins and she went off the rails again. Although it was long than before update.

You would need to create a thread describing your issue. This thread is referencing a Here4 with missing mag readings.

The tech will probably request a log file and a description of your setup. (and perhaps doing a calibration outside)

Will do. I’m going to try the here4 on a different drone and a here2 on the drone with the here4 on it and see if the results are reproduced…

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Hi, I have the same problem as Thomas. Is it possible that this is software, not hardware problem? UAVCAN Inspector didn’t show any MagneticFieldStrength report, thanks

@palma if you are running the latest firmware updated through mission planner and not seeing Magnetic Field Strength please contact your reseller for support.