Re: [avrdude-dev] program error?

[Brian Dean]

On Sun, Mar 23, 2003 at 01:33:28PM -0800, Sander Pool wrote:

> yes, this happens every time but I did not try the -e flag yet. I just tried
> that and it worked fine! This was without a verify though. When I added the
> verify flag back in and ran avrdude again it locked up like I reported
> earlier.

Just to make sure I understand ... you issue avrdude as so:

        avrdude -p m128 -e -i foo.hex

And it then programs OK, i.e., you don't get the verify error?

If so, then avrdude is working correctly - since after programming it
reads out the entirety of the flash, and compares the results with
what it just uploaded and they matched.

Just as an aside, '-e' is always necessary when you are updating the
flash, since the flash does not perform an auto-erase for each byte
programmed (the eeprom does, but not the flash).  Thus, programming
flash can only turn bits off, and if a bit is currently a '0', but
needs to become a '1', the subsequent verify will fail.  Doing a chip
erase sets the whole flash to 0xff, which is why '-e' is needed before
loading in a new program.

-Brian
-- 
Brian Dean
address@hidden
http://www.bsdhome.com/
http://www.bdmicro.com/