2.1 Overview

ATmega328PB ports have true Read-Modify-Write functionality when used as general digital I/O ports. This means that the direction, output drive value, or input pull-up enabling/disabling of one port pin can be changed without unintentionally changing other port pins. Most port pins are multiplexed with alternate functions for the peripheral features on the device. Enabling the alternate function of some of the port pins does not affect the use of the other pins in the port as general digital I/O.