APM 1280 upload problem

Hi guys, we are having some problems uploading firmware with Arduino to APM 1280 board when the size of the sketch is more than 122880 bytes (0x1E000).

I understand that bootloader starts at 0x1F000, so the maximum sketch size is 126976 bytes as Arduino shows.

What can be wrong? Tested on different boards and different computers. Arduino 0022 version.



Binary sketch size: 122904 bytes (of a 126976 byte maximum)


avrdude: verifying ...
avrdude: verification error, first mismatch at byte 0x1e000
         0xe1 != 0xff
avrdude: verification error; content mismatch

Thank you!!


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  • deleted

  • Hello, I have a similar problem to this day never had a problem with loading the firmware inAPM 1280. Planner using the APM.

    But with the update 251. I get an error in the verification.

    Detects the plate, internet download and up load the new firmware.

    Not if the same problem that exists in this thread.

    If so, how I can resolve this error?

    The plate is purchased in July 2010 Sparkfun.

    Sorry for my English, but only speak Spanish and I use the Google translator.


  • Hi Juampa,


    I changed those 2 fuses and the board is back to work again.  However, when I try to connect to APM Planner, it couldn't connect.  But I haven't had time to troubleshoot that yet.  Maybe it's another issue.  I have hard-coded some of the parameters i.e. GPS, disable logging to save space so that APM 2.20 can be uploaded to APM 1280.  So that might create another problem.  I'll update later.


    Thanks for this post!



  • I tried to upload to Arduino Mega board with success, then I just found the problem, my APM boards came with fuses set wrong.

    Boot flash start is wrong, preventing to write from 0x1E000 to 0x1EFFF.

    Comparing to Arduino Mega fuses the brown out detection is wrong too.

    I've set the fuses in APM board and now it's working.

    Who know how many APM boards are out there with wrong fuses?

    Take a look at BODLEVEL and BOOTSZ.

    My APM boards fuses:


    Arduino Mega fuses:


  • Developer

    I've uploaded sketches a few hundred bytes shy to a 1280 without problems. Older versions of AC2 were 125k.


  • Developer
    when your uploading do you have servos/ecs attached?
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