Difference between FreeRTOS libary (AVR_ATmega328PB_Xplained_mini_GCC) Versus FreeRTOS compatible for Arduino boards from Richard barrey
ATmega328PB is not the same MCU as used by Arduino boards. Those use ATmega328P (no B). ATmega328PB is a mostly compatible successor and offers more timers, built-in touch functionality and more but does not come in large DIP packages. Arduino uses the older ATmega328P.