WATSON INDUSTRIES GGC-E101, Руководство пользователя

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Watson Industries, Inc. GGC-E101 Rev A 08/30/2013
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$GPHDT Message Format
The $GPHDT 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:
$GPHDT,xxx.xx,T*cc<CR><LF>
1.
The ”$GPHDT” header indicates the start of the data string. . This data is followed by a
comma.
2.
“xxx.xx” is a variable character string (minimum-4, maximum-6) representing the gyro
stabilized true North heading 0.00 to 359.99 degrees. This data is followed by a comma.
3.
“T” is a single character representing the true North heading.
4.
“*cc” is a three character string representing an asterisk followed by a two digit
hexadecimal checksum.
5.
<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:
$GPHDT,175.58,T*0C
$GPHDT message Header
175.58 True Heading 175.58 deg
T True Heading
*0C Checksum
$GPGGA Message Format
The $GPGGA 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:
$GPGGA,hhmmss.ss,ddmm.mmmmm,s,dddmm.mmmmm,s,n,qq,p.p,saaaaa.a,M,
±xxxx.xx,M,sss,aaaa*cc<CR><LF>
1.
The ”$GPGGA” 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.
“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.
4.
“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.