Mavic 2 wants a compass calibration 30 days after last one

[sar104]

I try again. Thank you!

That calibration request was triggered by magnetic interference. But note that after successful calibration it stores both date and location.


-260.250 : 1743 [L-FDI]NS(0) COMPASS(0): fault on , interfere
-259.430 : 1791 [L-FMU/LED]action changed. compass out of range:need_cali(1)
-199.647 : 5294 [L-COMPASS][scale cali(0)] fill num:[149]
-199.647 : 5294 [L-COMPASS][scale cali(0)] estimation error:[9.6]
-199.647 : 5294 [L-COMPASS][scale cali(0)] succeed! bias:-127.7 -300.1 229.0 scal:2.946 2.879 3.090|
-199.647 : 5294 [L-COMPASS][save data] app cali all success
-199.647 : 5294 [L-COMPASS][save data] in user index mode
-199.647 : 5294 [L-COMPASS]mag cali pos and time saved success!
-199.647 : 5294 [L-COMPASS][mag_cali_pt]lat:0.760686, lon:-2.028914
-199.647 : 5294 [L-COMPASS][mag_cali_pt]height:850.0, date:20181006

 

[Former Member]

That calibration request was triggered by magnetic interference. But note that after successful calibration it stores both date and location.


-260.250 : 1743 [L-FDI]NS(0) COMPASS(0): fault on , interfere
-259.430 : 1791 [L-FMU/LED]action changed. compass out of range:need_cali(1)
-199.647 : 5294 [L-COMPASS][scale cali(0)] fill num:[149]
-199.647 : 5294 [L-COMPASS][scale cali(0)] estimation error:[9.6]
-199.647 : 5294 [L-COMPASS][scale cali(0)] succeed! bias:-127.7 -300.1 229.0 scal:2.946 2.879 3.090|
-199.647 : 5294 [L-COMPASS][save data] app cali all success
-199.647 : 5294 [L-COMPASS][save data] in user index mode
-199.647 : 5294 [L-COMPASS]mag cali pos and time saved success!
-199.647 : 5294 [L-COMPASS][mag_cali_pt]lat:0.760686, lon:-2.028914
-199.647 : 5294 [L-COMPASS][mag_cali_pt]height:850.0, date:20181006

In this specific case I guess the 30 days had nothing to do with the drone requesting calibration.

 

[sar104]

In this specific case I guess the 30 days had nothing to do with the drone requesting calibration.

There's certainly no mention previous calibration test in the log.

 

[Former Member]

There's certainly no mention previous calibration test in the log.

Could that be due to a date anomaly similar to what you have found in 1 other DAT file?

 

[sar104]

Could that be due to a date anomaly similar to what you have found in 1 other DAT file?

If it weren't for the specific mention of interference as the reason then I'd certainly wonder about that.

 

[Former Member]

What if the 30 day rule had something to do with the eventLog stream date of 2032 on @gnirtS but @sar104 and @BudWalker updated to 2018 correct date and time? Where would the eventLog stream be getting its data from? Is it possible that @gnirtS might need calibration less often since his has been calibrated for the next 14 years according to the eventLog stream file? His date of 2032 is 14 years into the future, so any calibrations before that date are not being recorded. Maybe the day after 20320216, 20320217, @gnirtS will show the updated calibration.

If DJI does not come up with a cure, maybe there is a way to fast forward the date on whatever chip is keeping track of the date, so an owner wont be prompted for continual calibrations.

 

[sar104]

What if the 30 day rule had something to do with the eventLog stream date of 2032 on @gnirtS but @sar104 and @BudWalker updated to 2018 correct date and time? Where would the eventLog stream be getting its data from? Is it possible that @gnirtS might need calibration less often since his has been calibrated for the next 14 years according to the eventLog stream file? His date of 2032 is 14 years into the future, so any calibrations before that date are not being recorded. Maybe the day after 20320216, 20320217, @gnirtS will show the updated calibration.

If DJI does not come up with a cure, maybe there is a way to fast forward the date on whatever chip is keeping track of the date, so an owner wont be prompted for continual calibrations.

Right - and that 2032 date likely came from a bug in the firmware. At some point, presumably before it had accurate GPS time, and possibly in its initial factor calibration, the aircraft thought it was 2032. That will mean it won't ask again, at least due to time elapsed. However, it will be interesting to see, if it is calibrated for a different reason, whether the date resets to current time.

 

[bcoles]

Was it calibrated 30+ days ago? I.e., did you calibrate it before the first flight? And, can you provide the tablet .DAT where it requested the calibration and then accepted the partial calibration? Look here to see how to retrieve the table .DAT.

I tried to retrieve my Dat files today and found them but was unable to read them. They came up as a text file and I was unable to read the text. This was on my iMac. Do I need a file manager app (recommend) to be able to read the Dat file? I seem to be getting a lot of compass calibrate requests. Bryan.

 

[sar104]

I tried to retrieve my Dat files today and found them but was unable to read them. They came up as a text file and I was unable to read the text. This was on my iMac. Do I need a file manager app (recommend) to be able to read the Dat file? I seem to be getting a lot of compass calibrate requests. Bryan.

CsvView Introduction

 

[Former Member]

Right - and that 2032 date likely came from a bug in the firmware. At some point, presumably before it had accurate GPS time, and possibly in its initial factor calibration, the aircraft thought it was 2032. That will mean it won't ask again, at least due to time elapsed. However, it will be interesting to see, if it is calibrated for a different reason, whether the date resets to current time.

That would be a big firmware bug. Especially if DJI needs to analyze flight logs to determine who is at fault in a warranty claim. Without proper date and time, how can they compare previous calibrations?

Do you think Airdata would give more precise info or is that fed by the eventLog stream file?

Strange and funny that it picked 2032 as the year if @gnirtS M2 was set at the factory. In China it's the year 4716 (Year of the dog), in Thailand it's the year 2561, and to the western world it's 2018. Lets hope the year of the dog doesnt refer to the M2. joking.

 

[sar104]

That would be a big firmware bug. Especially if DJI needs to analyze flight logs to determine who is at fault in a warranty claim. Without proper date and time, how can they compare previous calibrations?

Do you think Airdata would give more precise info or is that fed by the eventLog stream file?

Strange and funny that it picked 2032 as the year. In China it's the year 4716 (Year of the dog), in Thailand it's the year 2561, and to the western world it's 2018. Lets hope the year of the dog doesnt refer to the M2. joking.

It could be a tiny bug, but with bigger consequences. AirData doesn't read DAT files, and that's where the the event log is recorded.

 

[bcoles]

CsvView Introduction

I downloaded Csv for my iMac and then downloaded the Java script tool as well. When I opened my "FLT39.DAT with Csv it tells me it is unable to read the file. Obviously I'm still missing something. Bryan.

 

[sar104]

I downloaded Csv for my iMac and then downloaded the Java script tool as well. When I opened my "FLT39.DAT with Csv it tells me it is unable to read the file. Obviously I'm still missing something. Bryan.

I don't know - you would have to post the file here so that we could see what you are looking at.

 

[bcoles]

I don't know - you would have to post the file here so that we could see what you are looking at.

This is the file I'm trying to open. 2018-10-05_14-16-49_FLY039.DAT

 

[sar104]

This is the file I'm trying to open. 2018-10-05_14-16-49_FLY039.DAT

Yes - the filename looks fine. I'd need to see the file itself to understand why you can't open it.

 

[bcoles]

Yes - the filename looks fine. I'd need to see the file itself to understand why you can't open it.

Dropbox - 2018-10-05_14-16-49_FLY039.DAT sar104 Here is the file. I hope you can read it. Thanks, Bryan

 

[sar104]

Dropbox - 2018-10-05_14-16-49_FLY039.DAT sar104 Here is the file. I hope you can read it. Thanks, Bryan

The name of that file suggests that it is the correct kind of DAT, but it is far too small to be a real DAT file. It contains no valid data.

 

[BudWalker]

I try again. Thank you!

As @sar104 observed (below) the calibration was requested because "magnetic interference", not the 30+ day rule.

Has the M2P requested another calibration after the one you did for this flight?

It would be interesting to see the .DAT file immediately before you started getting the calibration request. Since the .DAT files are relatively small you could zip up several.

Did you add a tracker or some other external device? The calibration made a significant change. Here is the magMod before and after the calibration. It changes from about 1230 before the calibration to about 1500 after.

 

[bcoles]

The name of that file suggests that it is the correct kind of DAT, but it is far too small to be a real DAT file. It contains no valid data.

Your are right when I drag the file into the dropbox folder is shows the size as 836 bytes yet the flight recorders show the file size as 11.9 mb. I must be doing something wrong. Any ideas.

 

[BudWalker]

Your are right when I drag the file into the dropbox folder is shows the size as 836 bytes yet the flight recorders show the file size as 11.9 mb. I must be doing something wrong. Any ideas.

I looked at it briefly. I think it's dragging the file descriptor and not the actual file.