PreArm: Internal errors 0x400 l:234 cnstring_nan


Got this message - PreArm: Internal errors 0x400 l:234 cnstring_nan - after doing the COMPASSMOT.

Restart it and it was all good during the flight.

Cube Black + HERE3 (CAN) - Mini Carrier - 4.1.0


Any ideas what could it be?

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It’s a bug - I have seen this several times

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I have seen this also.

so what basically does it mean

I have just seen this too. I want to check the compass interference when the motors are running.

I am using Arducopter 4.1.3 with an official Pixhawk 1.

I have had this working back in January 2021 with whatever the Arducopter version was then. Has anyone actually had the magnetic/motor calibration test working in “recent” times?

Even with the “bug” Compassmot is still successful. At least that’s what I found.

I did not see any magnetic field at all on the graph.

I can calibrate my compass fine though on its own doing the x-y-z axis rotation calibration.

Ah, that’s different. What I saw was the error after the procedure completed but it worked.

I am using a separate standalone compass that is not built-in to the GPS.

My GPS has a compass which I am not using at all. I am using the Pixhawk compass but it is obviously the second compass since it will experience lots of noise.

My feeling is that this issue is related to using a standalone compass because I have had this drone working in the past doing magnetic interference tests but only when I used the compass built-in to the GPS.

Just experienced this issue as well with 4.1.4 on cube orange + Here3

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We got this IE (PreArm: Internal errors 0x400 l:234 cnstring_nan) after CompassMot calibration and SdCard logs download too

I also just got this on 4.1.3 on Cube Blue following a compass motor calibration.

Right and it completed?. The issue remains, carry on.

I’m getting the same 0x400 after running compas motor calibration, also requiring a restart to fix.
Both in QGroundcontrol and Missionplanner.
I’m also seeing a “Initialising Ardupilot” repeatedly (every 3 or so seconds) in the log.

I also have seen the ‘initializing ardupilot’ message during this… @dkemxr how do I tell if it completed correctly? It did complete, I did reboot and it started up fine, however I am reticent to fly the sUAS. It’s an octocopter that has already has 2 crashes and is not trust worthy whatsoever (yet).