146.2 SOFTWARE INTERFACEThis section describes the details of the serial port commandsthrough which the HI-305III GPS module is controlled andmonitored. The serial port commands allow users to set the receiverparameters, configure output message type, and retrieve statusinformation. The baud rate and protocol of the host COM port mustmatch the baud rate and protocol of the GPS receiver serial port forcommands and data to be successfully transmitted and received.The default receiver protocol is 4800bps, 8 data bits, 1 stop bit, andnone parity.6.3 NMEA OUTPUT MESSAGE SPECIFICATIONThe HI-305III supports NMEA-0183 output format as defined by theNational Marine Electronics Association (http://www.nmea.org).The currently supported NMEA messages for GPS applications are: