Cannot install 3.2, installation fails while reading hex

I have never been able to flash new firmware. Now that 3.2 is out I really want the new position hold mode. When I go to install firmware in mission planner I select 3.2. It goes through detecting board version, then reading hex. The bar starts to fill up and goes till about under the 75% point, then it stops and flashes up an error box "communication error- no connection". My cable and everything is fine. I have been using the same cable to monitor telemetry and program my apm for months without issue. What should I do?

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  • How are you powering the board? I have had problems with a laptop not supplying enough power through the USB port. Also just for the upgrade try unplugging things from the board and retrying.


    • I have tried to update both from my mac laptop and from my desktop pc. The board has been plugged directly into both. I have in the past tried with nothing connected to the board and also tried with the board powered by the flight battery. All with the same failures. 

      • What is the baud rate on the COM port that you're using?  Also, you aren't connecting with the COM port, right?  You're just selecting it and then going through the firmware upgrade process.

        What happens when you attempt to use another COM port on your PC?  Does it actually change in the drop down list?


        • 115200. No im selecting the com port but not hitting connect. Then trying to update the firmware. It won't even work if youre connected it just says you cannot update firmware while connected to mavlink.  

          Yes changing the com port changes it in the drop down, but doesn't seem to help anything.

  • I found a solution after reading another forum. I disabeled the other serial interfaces in the device manager then uploaded the ac3.2. Hope this will help you as well.

    • What exactly did you disable? I had three com ports listed. One said arduino. I deleted the other two, but still no success. 

      • I disabeled all ports but the one saying arduino. 

        • I have done the same. But unfortunately that doesn't seem to fix the problem for me. 

  • I just now experience the same problem. Never seen it before. 

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