The library functions eeprom_read() and
eeprom_write(), can be called to read from, and write to, the EEPROM
during program execution.
These functions are available for all Mid-range devices that implement EEPROM (described in eeprom_read Function and eeprom_write Function).
For convenience, the macro _EEPROMSIZE represents the
number of bytes of EEPROM available on the target device.