External compass initialisation issue

Hi everybody!

I just got an external compass for my apm2.5 2 days ago because I had a compassmot interferences above 100% :(

I received it 2 days ago and installed it. I tried it with the apm powered by usb and everything looked good. I even did a compassmot calibration which gave 6%. 

However once the quad set up I tried to fly it but was unable to arm it. I plug it on usb and managed to arm it. the issue seems to occur only when powered from the bec (3A). I checked that I had the required 3.3V on the I2C port.

I cleared eprom and reinstall everything with no luck. I also used 3dr modems to monitor what is happening and it says : compass not healthy.

I also have a led error code but I couldn't find the meaning the red led (A?) blink twice and then pause for 1 sec.

I don't know what else I can try... Any Idea?

thank you in advance.

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Replies

  • Hi!

     

    Problem solved! It had to do with the compass pull-up to 5V.

    I am not sure why, as I2C on APM is 3.3V, but when I enabled the pull up on the compass board it started to operate as expected.

    It is still a mistery why it was working on usb power and not on bec.

     

    Hope this can help if somebody have the issue. If somebody can explain why it was working on USB I am interested!

This reply was deleted.

Activity

Neville Rodrigues liked Neville Rodrigues's profile
Jun 30
Santiago Perez liked Santiago Perez's profile
Jun 21
More…