iSXblue/SXBlue II GNSS Series Technical Reference Manual
119
5.9.3
GLL Data Message
The GLL message contains Latitude and Longitude. In the table below, the GLL data message is broken
down into its components. This message has the following format:
$GPGLL,ddmm.mmmm,s,dddmm.mmmm,s,hhmmss.ss,s*cc<CR><LF>
Table 5-14 GLL Data Message Defined
Field
Description
ddmm.mmmmm
Latitude in degrees, minutes, and decimal minutes
s
s = N or s = S, for North or South latitude
dddmm.mmmmm
Longitude in degrees, minutes, and decimal minutes
s
s = E or s = W, for East or West longitude
hhmmss.ss
UTC time in hours, minutes, and seconds of GPS position
s
Status, s = A = valid, s = V = invalid
*cc
Checksum
<CR><LF>
Carriage return and line feed
5.9.4
GSA Data Message
The GSA message contains GPS DOP and active satellite information. Only satellites used in the
position computation are present in this message. Null fields are present when data is unavailable due to
the number of satellites tracked. The table below breaks down the GSA message into its components.
This message has the following format:
$GPGSA,a,b,cc,dd,ee,ff,gg,hh,ii,jj,kk,mm,nn,oo,p.p,q.q,r.r *cc<CR><LF>
Table 5-15 GSA Data Message Defined
Field
Description
a
Satellite acquisition mode M = manually forced to 2D or 3D, A = automatic swap
between 2D and 3D
b
Position mode, 1 = fix not available, 2 = 2D fix, 3 = 3D fix
Cc to oo
Satellites used in the position solution, a null field occurs if a channel is unused
p.p
Position Dilution of Precision (PDOP) = 1.0 to 9.9
q.q
Horizontal Dilution of Precision (HDOP) = 1.0 to 9.9
r.r
Vertical Dilution of Precision (VDOP) = 1.0 to 9.9
*cc
Checksum
<CR><LF>
Carriage return and line feed
