Hello All

I am using the standard ACM 1280 with MediaTek GPS Module firmware 1.6.

I first build a Quad and uploaded at that time 2.0.39 firmware and both MTEK Blue LED and ACM red LED (C) were working fine when I get a GPS Lock.

Lately I finish building a new Tricopter Frame and I used the same equipment the only difference is I updated the firmware to (Arducopter V2.0.49 Beta Tri) firmware.

and this is what is happening with me in the field:

  • The blue LED on the MediaTek module GPS is solid but the red APM GPS LED (C) is OFF.
  • If I connect the APM with the (Mission Planner) MP though USB, I get both the Blue and Red LED solid and it shows 3D GPS lock on the MP, but if I disconnect the USB the Red LED goes OFF again and the Blue is solid.

I really appreciate any help and opinions

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  • Dear Matthew

    After intense troubleshooting, I found the problem

    I am using a separate power supply for the ACM using an external BEC, it seems that the BEC that I used with the tricopter is giving me 5.6v, every time I connect to USB the ACM get its voltage from the USB port which is pure 5v.

    So I connected the BEC that I used when I first build the Quad which gives me 5.13v and everything worked fine, now I get GPS lock both the Blue and Red LED.

    I'll go for a flight test tomorrow to see if I can get the Loiter working. Thanks Matthew for your reply, as it is the only reply I got, really appreciate it.

  • The suggestion may be made to upload again using the Arduino software and configure it for Tri manually.  The Arduino always does a good job and it cleans out the boards memory - which is important.  Funny things happen if parts of other configs are left intact.

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