Mini Apm Pro clone / Compass Calibration

Hi everyboady can you help me please?.. I got a APM Pro clone and a BN880GPS but I got a bad compass health and i cant calibrate it.. When I disable MAG, bad compass health disapears but I still got a Compass1 99 error and no calibtration and weirdly I can see on the panel my heading moving... Even when I disable all compass parameters.. I think this APM based on APM 2.6 has a mag in but to use a external compass you might disable something on the board or do something I think.. I tried all that I found and spent a lot of time on the web to find solution but no way... Test the SCL, SDA wires has a 3.2v with GND... Here is my APM Pro



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  • Hi everybody,
    All my wires are correctly connected... TX on RX and TX on RX, SDA to SDA and SCL to SCL.. My problem is when I upload the Rover firmware, I got a GPS lock and and a heading on my compass but when I upload Arducopter firmware I dont have GPS lock and heading at the same place... So I think I got a problem with my APM Pro, I did not know it was a clone, when I opened it it saw that... I will buy another one... But when I upload the Rover firmware I got GPS and heading and Arducopter not... Where can I donwload older firmwares?... Or someone can share his parameter file with me?..

  • ok I seem to have found the controller.

    From the M8n you should have 6 wires, 4 from GPS and 2 for the i2c mag. You would connect the GPS to the GPS pins circled and the mag to the 2 pins circled. [in the attached image]

    Remember the TX and RX need to be crossed that the SCL/SDA are NOT crossed.


  • There is no mag on that board [you can see the missing chip under the misspelled "Ardupiolt" lol] 

    You can see the reticle moving because it is using the gyro.

    You NEED a mag connected before you can calibrate it.

    I've seen a LOT of APMs over the years but never one that looks like the one in the image. And so without a link to where you got it I am unable to help on how to properly connect your m8n gps/mag to it :(

  • Unfortunately I'm on the mobile site and can't see your picture but the mini apm pro has an onboard compass and there is no calibration. You will first need to check the SCL SDA cables. The most common problem I have had is either having those cables (normally Green and Yellow colour) around the wrong way or one position to the right by mistake. Check you have the cables on the far right of the pins green on the outer edge yellow toward the centre of the board, it is the most common problem I'm aware of. Just remember there is no calibration and just check the compass is turned on, if you still have problems let me know I will try help but if anyone else has more info or has found any new results I am interested as well because the compass calibration has long been an issue with the mini APM pro.
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