ashtech DG16 Reference Manual page 266

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.
Example
Enter the following command to enable GST message on port B.
$PASHS,NME,GST,B,ON
$PASHQ,GST,[c1]
This command queries the GST message, where c1 is the optional port designator
for the output of the response. If a port is not specified, the receiver sends the
response to the current port.
$GPGST
The GST message contains UTC time, the RMS value of the standard deviation
for satellite range measurements, and the corresponding standard deviation values
for latitude, longitude, and altitude. The response is output in the format:
$GPGST,m1,f2,f3,f4,f5,f7,f8,f9*hh
Table 8.18 outlines the message format.
Parameter
m1 UTC time (hhmmss.ss) of the position fix
f2 RMS value of the standard deviation of the satellite range inputs to
the navigation processor. This field is related to remaining fields as
follows:
• (RMS value of standard deviation range inputs)
(Standard deviation of latitude error)
longitude error)
• (RMS value of standard deviation of range inputs)
(Standard deviation of altitude error)
f3 Standard deviation of semi-major axis of error ellipse (meters).
f4 Standard deviation of semi-minor axis of error ellipse (meters).
f5 Orientation of semi-major axis of error ellipse (degrees from true
north).
246
Table 8.18. $GPGST Message Format
Description
2
DG14 and DG16 Board & Sensor Reference Manual
2 2
* (HDOP) =
2
+ (Standard deviation of
2 2
* (VDOP)
2
Range
000000.00 to
235959.95
0.00 to 99.99
=
0.00 to 99.99
(might be an
empty field)
0.00 to 99.99
(might be an
empty field)
0.00 to 99.99
(might be an
empty field)