Magellan GPS ColorTRAK, Руководство пользователя

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Magellan GPS ColorTRAK 67
GSA GPS DOP and Active Satellites
GPS receiver operating mode, satelites used in the naviga-
tion solution reported by the $--GGA sentence, and DOP
values.
1 2 3 4 5 6 7
GSA,a,x,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,x.x,x.x,x.x*hh<CR><LF>,
1 Mode: M=Manual, forced to operate in 2D or 3D mode,
A=Automatic, allowed to automatically switch 2D/3D
2 Mode: 1= Fix not available, 2=2D, 3=3D
3-4 PRN numbers of satellites used in solution (null for
unused fields)
5 PDOP
6 HDOP
7 VDOP
GSV GPS Satellites in View
Number of satellites (SV) in view, PRN numbers, elevation,
azimuth and SNR value. Four satellites maximum per transmis-
sion, additional satellite data sent in second or their
message. Total number of messages being transmitted and the
number of messages being transmitted is indicated in the
first two fields.
1 2 3 4 5 6 7 8 910 11
GSV,x,x,xx,xx,xx,xxx,xx..........xx,xx,xxx,xx*hh<CR><LF>
1 Total number of messages, 1 to 3
2 Message number, 1 to 3
3 Total numer of satellites in view
4 Satellite PRN number
5 Elevation, degrees, 90
°
maximum
6 Azimuth, degrees True, 000 to 359
7 SNR (C/No) 00-99 dB, null when not tracking
8-9 2nd-3rd SV
10-11 4th SV
Notes: 1) Satellite information may require the transmission
of multiple messages. The first field specifies the total
number of messages, minimum value 1. The second field iden-
tifies the order of this message (message number), minimum
value 1.
2) A variable number of “PRN-Elevation-Azimuth-SNR” sets are
allowed up to a maximum of four sets per message. Null
fields are not required for unused sets when less than four
sets are transmitted.