mRo GPS u-Blox Neo-M8N Dual Compass LIS3MDL+ IST8310 (Problem)

Hallo!
Bought a set of mRo. The kit includes GPS with a compass. It turns out there are two compasses on the board. And they are directed in different directions. Mission planner defines as 3 compass. But how can I determine which compass is 1, which is 2, and which is 3? I also need to set the 2 external compasses direction.

Maybe if the jumpers (red) are soldered, then I will disconnect one of the two compasses? and it will be easier.

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They can be determined from the compass Device ID’s if you want to post your parameter file.

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Hello.
Yes, I found now such parameters in the full list of parameters. How to find the ID of the internal compass or one of the external. Is it supposed to be written in datasheet?

Only way I know is to run the attached Python script.
Compass decode.zip (1.2 KB)

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Wow, thanks and how to use it? Can I run it through the Mission Planner?

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No. 1st you have to install the Python Interpreter and then run it from Windows command prompt. If you want to post your device ID’s I’ll do it if you like.

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OK, I’ll be back home in the evening, I will try, thank you.

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Tried the whole evening does not work.:confused: Writes: “Invalid syntax”. These are the Id numbers I have. Maybe you can do it.
ID:531977
ID2:658953
ID3:131594


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Here you go!
ID:531977- LIS3MDL
ID2:658953- IST8310
ID3:131594-LSM303D

How many internal compass’s does you flight controller have? It would be interesting to see what’s reported for Device ID’s with no external compass’s connected.

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Wow, thanks. Internal compass ID: 131594. I have a flight controller from mRo too. Interesting. Why I could not see the ID numbers?

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Which Flight Controller? So with no external compass connected at all it only shows 1 compass ID? Just trying to confirm that the 1st 2 compass’s are in fact external. It would seem so.

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Yes, if not connected. Shows only internal. The remaining IDs are 0

Here is a flight controller. Here is a flight controller.
https://store.mrobotics.io/product-p/mro-pixhawk1-fullkit-mr.htm

Now I can not understand how to set the orientation. It seems to automatically set none. All the same, I want to understand where x should be, where y. What am I confused.

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The “Y” arrow would point towards the rear of the craft for “rotation 0” as I recall so the IST 8310 would require either Yaw 90 or Yaw 270, not sure which,if the LIS3MDL is mounted that way.

You could install the dev version of firmare and enable on-board compass learning for the FC to determine orientation and then flash back to stable after its complete.

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Hi. I want to jump into this discussion with a question about calibrating this dual compass unit. I have 4 of these mRo units. Two were purchased in 2018 and two in 2019. The 2019 units were upgraded with RGB LEDs. I can calibrate the older units but not the newer ones. I am using mRo Pixhawk 1’s set up to recognize the external compasses in the GPS unit. The newer units will flash the RGB lights during the calibration procedure but I don’t know what they’re telling me. All I know is that the two green progress bars will move along until one of them completes and then I get a failure message, and the process starts all over again. I have done as many as 4 repeats and no luck.

Can anyone offer any suggestions to resolve this?

Thanks,
Joe

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Good day,
me im using the same units without any issue, just keep your gps far from any magnetic interferences… Just try also to change the rotation of the module and when you are doing the calibration just rotate it randomly in all the axis…

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just let me know if you need suggestions and the results pls

Post a screen shot of the HW ID screen after connecting. Let’s see what’s being recognized. Clearly 2 are if the bars are advancing but it could be usefull anyway.

Here’s the HW ID screen:

This is the calibration screen. Only one compass seems ot calibrate but not the other. I get the same result with another identical GPS module. It flashes with a blue light during this process.

image

Joe

UPDATE: I tried several combinations.

  1. Just Mag2 (also primary), and it calibrated with one compass on the Relaxed setting, but not the Default setting. (First screen)

  2. Both mags, Compass 1 primary, no calibration on either default or relaxed.

  3. Both mags, Compass 2 primary, calibrates on relaxed, but not default. (Second screen)

But the Mag1 offsets in red bothers me.

image

image

Good day,
Did you try reposition the module?
You mount it on a stand or?