arduino, avrdude verification error

[loungelover]

hi I am Having a bit of a problem with the AVR on my Gertboard. I had the button and the blink sketches working yesterday but i think i may have connected 5v to analogue 0. Today I cant get any of the sketches to work i keep getting a "avrdude verification error content mismatch" message.

[DirkS]

Are you using the Arduino IDE? If yes, try using 'Upload using programmer' from the File menu instead of using the standard upload function.
Apparently this erases the chip before uploading (the standard 'upload' does not) and it solved my verification problems.

(see https://projects.drogon.net/raspberry-p ... mment-1232 for some relevant comments on Gordon's article on using the IDE with the Gertboard)

Gr.
Dirk.

[loungelover]

yeh that got it. up and blinking now!

thanks

[DirkS]

my pleasure!

[pschaeffer]

Dirk S has already provided the right suggestion in this case. However, the following may be helpful. AVRDUDE verification errors have an interesting origin.

What is frequently happening is that the upload didn't work at all (for various reasons) and the subsequent verification fails. The way AVRDUDE works is that it does all of the upload work first, and then does the verification second. The upload process doesn't appear to have any checks built-in. If every part of the upload fails, you won't know anything about it at this stage. Of course, the verification will fail. If the new upload is only slightly different than the old upload the first mismatch can be far into the flash (not at offset 0x0000).

Why can upload fail? Many reasons of course. I have had good results using the 'Arduino as ISP' approach to uploading sketches. This approach does not use the bootloader at all. That's important when you can't trust the bootloader. Note that you MUST use the 'Upload Using Programmer' command from the file menu and not the normal upload button.