1.1 Additional Pin Functionalities

ATmega324PB supports seven additional GPIOs on PORTE [6:0].

The GPIO pins PE0, PE1, and PE4 are assigned to Pin7, Pin8, and Pin29. PE0, PE1, and PE4 are multiplexed with XTAL2, XTAL1, and AREF.

The GPIO pin PC5 is multiplexed with ACO, the Analog Comparator output.

Pin17(VCC), Pin18(GND), Pin38 (VCC), and Pin39 (GND) are replaced by PE2, PE3, PE5, and PE6 respectively.

Table 1-1. Pin Functionality Difference between ATmega324 Variants and ATmega324PB
44-pin TQFP/MLF packageATmega324 variantsATmega324PB
Pin 7XTAL2PE0 (XTAL2)
Pin 8XTAL1PE1 (XTAL1)
Pin 17VCCPE2
Pin 18GNDPE3
Pin 29AREFPE4 (AREF)
Pin 38VCCPE5
Pin 39GNDPE6