Hi!
Now trying to upload new firmware to Arduino 2560 however getting "Read Failed. Connection unavailable" after clicking Configure button.
First thing I did wrong - tried to configure EEPROM with old firmware, config utility suggested to repair it, I proceeded. Then I uploaded .hex using avrdude and then using config utility again. I uploaded previous firmware I used, now configuration works well.
I saw the commentary about resistor. Does it cause the issue? Sorry, haven't got the idea yet.
Thank you.