Serial Communication Library for Arduino Zero

Hello,

I'm trying to do a RS-485 communication between two Arduino's, implementing Max 450. However, the Arduino Zero is 48 Mhz and when I use it, I keep getting this error. Can some please help?

C:\Program Files (x86)\Arduino\libraries\NewSoftSerial\NewSoftSerial.cpp:43:24: fatal error: WConstants.h: No such file or directory

#include "WConstants.h"

^

compilation terminated.

exit status 1
Error compiling for board Arduino/Genuino Zero (Programming Port).

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