ashtech HDS800, Reference Manual

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Using the Web Server
Rover Operating in
Hot Standby RTK
Hot Standby RTK is the process of making available a second
RTK position solution in the background. Should the primary
RTK solution stop being delivered by the receiver for some
reason, then the second RTK solution would be provided
instead, until the primary RTK solution is back again and
valid.
If you wish to make available this background solution, then
enable the
Hot Standby RTK
option at bottom of the page. You
are then asked to specify which port will route the differential
corrections used to compute that solution (you should use a
source of differential corrections different from the one used
for the primary solution; make sure this source of corrections
will be delivered on the specified port).
Defining Output
Messages
Depending on your application, you will have to define
different types of data output messages as well as the way
they are delivered to outside equipment (typically through a
serial port for a rover).
Three categories of output data are possible (NMEA,
differential and raw data) but in most rover applications, only
the use of NMEA messages makes sense.
However, to allow raw data to be recorded in the rover, you
should make sure the appropriate messages are set on the U
and M ports.
Follow the instructions below to program the desired
messages:
• On the
Configuration
tab, click on the
Data Output
menu.
• Click on the
NMEA Messages
submenu. Use the page that
opens as explained below:
– All possible NMEA message types are listed below.
Message Name Description
ALM Almanac data for each of the tracked satellites
ATT Computed attitude data (not supported)
CRT Cartesian coordinates of computed position
DCR Cartesian coordinates of computed baseline
DDS Differential decoder status
DPO Delta position (baseline components)
DTM Datum Reference
GGA Standard GNSS position message
GLL Latitude and longitude of computed position
GNS GNSS fix data
GRS GNSS range residuals
GSA GNSS DOP and active satellites