The ATmega328PB has two new pins, PE0 and PE1, that have no equivalent on the ATmega328P. These pins do not yet have official pin numbers in the Arduino environment, so if you need to use their pin ...

There are three ways to specify a pin: By its pin number; By its AVR pin name, using the IO_* macros that this library provides. For example, IO_D3 refers to pin PD3. By alternative names defined in ...