WATSON INDUSTRIES GGC-E101, Руководство пользователя

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Watson Industries, Inc. GGC-E101 Rev A 08/30/2013
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11. “*cc” is a three character string representing an asterisk followed by a two digit
hexadecimal checksum.
12.
<CR><LF> The string is terminated by a carriage return and Line Feed. There will then be
a short interval with no data transmission before the next string begins.
Example:
$GPVTG,186.55,T,187.35,M,0.13,N,0.24,K,D*25
$GPVTG message Header
186.55 True Course over ground 261.74 degrees
T True Heading
187.35 Magnetic Course over ground 262.26 degrees
M Magnetic Heading
0.13 Speed over ground 0.13 knots
N Knots
0.24 Speed over ground 0.24 Km/hr
K Km/hr
D Mode Indicator = Differential
*25 Checksum
$GPRMC Message Format
The $GPRMC consists of a string ASCII characters sent asynchronously at regular intervals. The
string is sent at 9600 baud with eight data bits, one stop bit and no parity. The contents of this
string are formed as follows:
$GPRMC,hhmmss.ss,ddmm.mmmmm,s,dddmm.mmmmm,s,zzz.zz,ttt.tt,ddmmyy,ddd.d,v,
i*cc<CR> <LF>
1.
The ”$GPRMC” header indicates the start of the data string. This data is followed by a
comma.
2.
“hhmmss.ss” is a nine character string representing the Universal time in “hh” hours, “mm”
minutes, “ ss” seconds and “.ss” decimal fraction seconds at the GPS position. This data is
followed by a comma.
3.
“a” is a single character representing the Status. a = A for data valid,
a = V for data invalid. This data is followed by a comma
4
“ddmm.mmmmm” is a nine character string representing the Latitude in “dd” degrees,
“mm”minutes, and “.mmmmm” decimal fraction minutes. This data is followed by a
comma.
5.
“s” is a single character representing the Latitude direction. s = N for North Latitude, s = S
for South Latitude. This data is followed by a comma.
6.
“dddmm.mmmmm” is an eleven character string representing the Longitude in “ddd”
degrees, “mm” minutes, and “.mmmmm” decimal fraction minutes. This data is followed
by a comma.