Skysurfer-14

I get the same error, when I use the board "Atmel ATmega328PB". It would be very helpful to add the support of ATmega328PB and its variants (Elector UNO R4, Wattuino...

Thank you! I've made some first tests after `pio update` and inserting the boards-file and pins_arduino.h in directory R4. - `Serial.begin(9600);` and `Serial1.begin(9600);` compiles - `#include ` and `#include `...