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Geonics Limited
AAAAA.2 Description of GGA and GSA Data Messages
.2 Description of GGA and GSA Data Messages
.2 Description of GGA and GSA Data Messages
.2 Description of GGA and GSA Data Messages
.2 Description of GGA and GSA Data Messages
GGA Data Message
GGA Data Message
GGA Data Message
GGA Data Message
GGA Data Message
The GGA message contains the GPS position information and it is the most widely used NMEA
data message. This message takes the following form:
$GPGGA,hhmmss.ss,ddmm.mmmmm,s,dddmm.mmmmm,s,n,qq,pp.p,saaaaa.aa,u,
+xxxx.x,M,sss,aaaa*cc<CR><LF>
Definition of GGA message component:
hhmmss.ss
UTC time in hours, minutes, seconds of the GPS position
ddmm.mmmmm
Latitude in degrees, minutes, and decimal minutes
s
s=N or s=S, for North and South latitude
dddmm.mmmmm
Longitude in degrees, minutes, and decimal minutes
s
s=E or s=W, for East and West longitude
n
Quality indicator, 0 = no position, 1 = raw, no differentially corrected
position, 2 = differentially corrected position, 9 = position computed
using almanac information
Number of satellites used in position computation
pp.p
HDOP = 0.0 to 99.9
saaaaa.aa
Antenna altitude
u
Altitude units, M=meters
+xxxx.x
Geoidal separation (requires geoidal height option)
M
Geoidal separation units, M = meters
sss
Age of differential corrections in seconds
aaaa
Base station identification
*cc
Checksum
<CR><LF>
Carriage return and Line feed
GSA Data Message
GSA Data Message
GSA Data Message
GSA Data Message
GSA Data Message
The GSA message contains active satellites and PDOP value. The GSA message is given in the
following form:
$GPGSA,c1,d1,d2,d3,d4,d5,d6,d7,d8,d9,d10,d11,d12,d13,f1,f2,f3*cc<CR><LF>
Definition of GSA message components:
c1
Mode, M = manual, A = automatic
d1
Mode, 2 = 2D, 3 = 3D
d2-d13
Satellites used in position computation (range 0 to 32)
f1
PDOP (range 0 to 99.9)
f2
HDOP (range 0 to 99.9)
f3
VDOP (range 0 to 99.9)
*cc
Checksum
<CR><LF>
Carriage return and Line Feed
Summary of Contents for EM61MK2A
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