GPS Receiver to BL4S200 PortC Connection

In Samples Code GPS.C it assumes hardware used GPS receiver attached to serial port C, May I know how to connect the GPS receiver wire to BL4S200 portC (RS485)? Please help and advise.

The GPS receiver uses RS232 so you will need to connect it to serial port E or F on J11 and then modify the sample to use that port instead of serial port C.