I will implements an emergency backup feature before power off, on Arduino Mega 2650. Arduino is powered by capacitor, for the time (I hope) of the EEPROM write.
On AVR2650 Datasheet is reported that the typical EEPROM writing time is 3.3ms. But 3.3ms for what? a byte? a word? the whole EEPROM?
I need the data for calculate the capacitors.