Holux GR-213U User Manual
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NOTE: Items <4>,<5>,<6> and <7> repeat for each satellite in view to a maximum of four (4) satellites per
sentence. Additional satellites in view information must be sent in subsequent sentences. These fields will be
null if unused.
5.1.5 Recommended Minimum Specific GNSS Data (RMC)
Table 5-9 contains the values for the following example:
$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598, ,*10
Table 5-9 RMC Data Format
Name Example
Units
Description
Message ID
$GPRMC
RMC protocol header
UTC Time
161229.487
hhmmss.sss
Status
A
A=data valid or V=data not valid
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
Speed Over Ground
0.13
knots
Course Over Ground
309.62
degrees True
Date 120598
ddmmyy
Magnetic Variation (1)
degrees E=east or W=west
Checksum *10
End of message termination
1. SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are geodetic
WGS84 directions.
5.1.6 Course Over Ground and Ground Speed (VTG)
Table 5-10 contains the values for the following example:
$GPVTG,309.62,T, ,M,0.13,N,0.2,K*6E
Table 5-10 VTG Data Format
Name Example
Units
Description
Message ID
$GPVTG
VTG protocol header
Course 309.62
degrees
Measured
heading
Reference T
True
Course
degrees
Measured
heading
Reference M
Magnetic
(1)
Speed
0.13
knots
Measured horizontal speed
Units N
Knots
Speed
0.2
km/hr
Measured horizontal speed
Units
K
Kilometers per hour
Checksum *6E
End of message termination
1. SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are geodetic
WGS84 directions.
5.1.7 ZDA—SiRF Timing Message
Outputs the time associated with the current 1 PPS pulse. Each message will be output within a few
hundred ms after the 1 PPS pulse is output and will tell the time of the pulse that just occurred.
Table 5-11 contains the values for the following example:
$GPZDA,181813,14,10,2003,00,00*4F