RoyalTek RGM-2000 - Manual (Page 39)

Software Data
NMEA V2.2 Protocol
It is the RS-232 interface：4800 bps, 8 bit data, 1 stop bit and no parity.
NMEA Output Messages
The Sapphire outputs the following messages as shown in Table 1：
TABLE 1 NMEA OUTPUT MESSAGES
NMEA Record Description
GGA Global positioning system fixed data
GSA GNSS DOP and active satellites
GSV GNSS satellites in view
RMC Recommended minimum specific GNSS data
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
TABLE 2 GGA DATA FORMAT
Name Example Units Description
Message ID $GPGGA GGA protocol header
UTC Position 161229.487 hhmmss.sss
Latitude 3723.2475 ddmm.mmmm
N/S Indicator N N=north or S=south
Longitude 12158.3416 dddmm.mmmm
E/W Indicator W E=east or W=west
Position Fix Indicator 1 See Table 5-1
Satellites Used 07 Range 0 to 12
HDOP 1.0 Horizontal Dilution of Precision
MSL Altitude 9.0 meters
Units M meters
Geoid Separation meters
Units M meters
Age of Diff. Corr. second Null fields when DGPS is not used
Diff. Ref. Station ID 0000
Checksum *18
＜CR＞＜LF＞ End of message termination