I am recently working on building a communication system involving multiple arduinos and plan to use RS-485 modules as the distances I need to cover are fairly large (in the order of Km).
But , the problem is that, I am unable to use the RS485_protocol.h library. I installed and imported the zip file into the IDE , but everytime I get an error message saying that such a library already exists.Directly using (#include " RS485_protocol.h" ) along with the softwareserial library gives other error messages like "no reference to sendMsg and recvMsg". I have also tried installing the HardwareSerialRS485.h library , but with no effect . What to do? Plz help me out.