Datasheet

Page-write support in the AT28C256 can significantly speed up programming, but it depends on tight timing. The Arduino Mega is too slow to use this feature reliably, while faster platforms like the Arduino Due make it practical and stable.

Both DATA and RDY/!BUSY polling methods cut EEPROM write wait time by roughly threefold compared to fixed delays. They deliver similar performance and are simple to implement on Arduino. The limiting factor is the Arduino’s processing speed, not the AT28Cxx IC.