Verification Error

Hey guys, I have been working on a fairly large bit of code, and for a while now it has been giving me verification errors after uploading.

The sketches DO still seem to work, despite this error, but it'd be nice to get rid of it.

It only happens with this sketch - so doesn't seem like a problem with dead ATMega's etc.

avrdude: verification error, first mismatch at byte 0x2e23 0x80 != 0x82 avrdude: verification error; content mismatch

Does that point to any specific point in my code or spmething? I have read that sometimes it complains if you try and upload really large chunks of code?

Cheers, Dan

This errors means that AVRDude fails to read back whatever content it has written. This implies that either the written content is flawed or that the verification read failed for other reasons. Yes it points at a specific location in the compiled code. 02xe23. My first step would be to use AVRStudio or AVRDude from the commandline and see if it is possible to read the contents of the chip. Then I would compare this with whatever should have been written. It might also be that this specific memory cell is damaged. No clue how something like this should happen but it might happen.

Step 1: narrow down the possibilities.

I had a similar problem when playing around with the very wonderful Gameduino. I was defining a character set of 256 characters (16 bytes per character) but only bothered to define characters for 'A' to 'Z' leaving all the others blank. According to a post from the old forum avrdude can fail to program properly if there are long stretches of 0 or 1 bits. I changed all the unused characters to non-blank shapes and suddenly the verification error went away.