New ArduPilot2.5+, never flown, only connected with USB and board has been working flawlessly for 4 days while I learned Mission Planner and browsed the code.  Today I got the error "Upload succeeded but verify failed: exp C got 14 at 0" when uploading firmware.

I now get the error using Mission Planner or Arduino IDE to do an upload.  Does not matter if I am uploading ArduPlane V2.70, ArduCopter quad or older versions. I have found at least 4 other references to this issue various places on web forums but no information as to the cause or how to fix the problem.

Except for the verify error, the board and software seem to work the same as before the verify error.

Main question:  How do I fix this problem - make the verify error go away?

Related questions:

Is it a corrupted boot loader?  

  • If so, do I return the board to 3DRobotics ( place of purchase) or do I have to buy the hardware and get the software to replace the boot loader (Yuk - time, money, frustration)?
  • How in the world does the bootloader get corrupted?  Is it not protected?
  • Was It me? I did do a few minor changes in the ArduPlane code (Using Arduino IDE) to try to debug a CLI issue in Mission Planner  (see  here )
    Changes were simple - like add a delay(500); at several places along with a message for CLI.  Example:
    cliSerial->println_P(PSTR("\nAfter Ld Parms\n")); // ********Test ****  
    No other changes except inserting similar statements in various places - one at a time. 
  • Or, can Ardunio IDE change that address during an upload?
  • Or, could a bug in the ArduPlane code overwrite that address?

Is it a bad board?  

  • I do not think so because everything else seems to work in Mission Planner (board on desk)  Gyros work, compass works, AHRS works, setup works, CLI works - but only after a reboot if in Mission Planner (This is a separate issue - see  here ) 

Should I use this board in a plane without fixing the error?

  • Some discussion somewhere indicated this was a fuse in the boot area (adress 0?).  If that is so, then I would tend to ignore the message and proceed with installation and flight tests.  Any suggestions?

Thanks in advance for any help you can provide.

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  • I had the same problem:

    "upload succeeded but verify failed: exp 8c got DC at 102254".

    As for me, the problem happened because I use Windows VM on MAC (VMware fusion hypervisor). It's very common issue when you use Serial port on a VM.

    Try to use Windows box to upload the firmware. It helped me so potentially it may help you.

  • Solution found after hours of searching:  

    I get it now.  No one replied so I could learn this the hard way - called educate the newbee  :)

    The problem was that the lock bits on the 2560 mcu had been set to a value of 0xC3 instead of the desired value of 0xCF.  The bad value had BLB0 set to LPM_SPM_DISABLE  which prohibits reading and writing to some part of memory - not sure which part - that is another research project. I will never know how the values got changed.

    Of course to find the problem required information from  3DR support (thanks) as to what the values should be, and then I had to buy an ISP programmer, install AVRStudio, erase the 2560 chip, set the lock bits back to the way they should be and upload the 2560 boot loader for the AP2.5. Since this was such a difficult task I am going to open a new topic later and detail how to re-install the boot loader for the 2560 chip.  Just finding the hex file for the boot loader was not easy - although 3DR support is in the process of sending me the file - just forgot to attach it.  Also the ISP connections on the AP2.5+ is not documented anywhere I could find.  Where the six pins are is on the drawing but which pin is pin 1 is not marked on the drawings. Lucky one pin on the circuit board has a square land - so I guessed and it was pin 1.  

    This should all be on the wiki somewhere one would think.  Anyone out there know how to go about helping get this info documented somewhere except in this forum.  I can do the text etc but don't know how to go about the wiki stuff.

  • OK, perhaps that was too much data.  

    When I upload firmware I get "Upload succeeded but verify failed: exp C got 14 at 0"

    Can anyone tell me what that means and what to do next?   No answer from 3dr re my service request.

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