Arduino DUE SoftwareSerial problem?

[LaCasaDePapel]

I'm using Arduino DUE and I get an error like this.What do you think is wrong?

[ard_newbie]

There is hardware serial on a DUE and softwareSerial is for AVRs only. However, antodom has written a soft UART library :

GitHub - antodom/soft_uart: This is an implementation of a software UART...