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RGM-3550LP User Manual
7. Software Specification and NMEA Protocol
Software Specification
GPS Firmware
- Standard SiRF firmware for SSIII (GSW3 & SiRFLoc 3)
- Upload firmware
- RGM-3550LP [GSW3][SBAS GGA(1), GSA(1), GSV(1),
RMC(1) 9600 GPS Firmware, version 2.1.0.123 (default)
GPS Utility
- A GPS performance diagnostic utility is required
- C/NO, TTFF
WAAS
- Enable
GPS status
- See GPS status light indicating specification
NMEA V3.0 Protocol
Its output signal level is TTL: 9600bps (default), 8 bit data, 1 stop bit and no parity. It supports
the following NMEA-0183
Messages: GGA, GLL, GSA, GSV, RMC and VTG.
NMEA Output Messages: the Engine board outputs the following messages as shown in Table
1:
Table 1 NMEA-0183 Output Messages
NMEA Record Description
GGA Global positioning system fixed data
GLL Geographic position – latitude / longitude
GSA GNSS DOP and active satellites
GSV GNSS satellites in view
RMC Recommended minimum specific GNSS data
VTG Course over ground and ground speed
GGA-Global Positioning System Fixed Data
Table 2 contains the values of the following example:
$GPGGA, 161229.487, 3723.2475, N, 12158.3416, W, 1, 07, 1.0, 9.0, M, , , ,0000*18
