ashtech DG14, Справочное руководство

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NMEA Commands 233
NMEA Commands
GGA: 3-D GPS Position
$PASHS,NME,GGA,x,s,[f]
Enable or disable NMEA GPS position response message on port x, where x is the
output port A, B, or C. s is ON or OFF. f is the optional message output rate ranging
from 0.05 to 999 seconds depending on the measurement update rate option
installed.
If the command is set without a period, the DG16 uses the period set by the
$PASHS,NME,PER command If the $PASHS,NME,PER command is issued after
this message period has been set, the period resets to the PER setting.
$PASHS,GGA,x,[f]
This command enables the receiver to output either the entire GGA message
(x=FUL) or the standard GGA message (x=STD). NMEA standards restricts the
length of any message to a maximum of 82 characters, including the header,
checksum and
<CR><LF> characters. f is the optional message output rate ranging
from 0.05 to 999 seconds depending on the measurement update rate option
installed.
If the command is set without a period, the DG16 uses the period set by the
$PASHS,NME,PER command If the $PASHS,NME,PER command is issued after
this message period has been set, the period resets to the PER setting.
A GGA message output in the FUL format may exceed the maximum length of 82
characters to accommodate the highest level of resolution (recommended in RTK
mode). Some software and hardware devices which accept NMEA inputs may reject
or ignore NMEA messages that exceed the maximum length; in those cases, the
STD format should be selected.
When using the STD format, leading zeroes in numeric fields and plus signs (+) for
positive values are eliminated and the geoidal separation value is rounded to the
nearest meter. This allows the GGA message to comply with the maximum length
restriction.
M geoidal separation units (M = meters)
014 age of corrections
1010 Differential Station ID
W84 Reference datum is WGS 84
2A checksum
Table 8.6. Typical GDC Message
Item Description