4 configuration notes – Novatel GNSS Receiver and Antenna SMART-AG User Manual
Page 37
Operation
Chapter 3
SMART-AG User Manual Rev 5
37
3.3.4
Configuration Notes
For compatibility with other GNSS receivers, and to minimize message size, it is recommended that
you use the standard form of RTCA, RTCM, RTCMV3 or CMR corrections as shown in the base and
rover examples above. This requires using the INTERFACEMODE command to dedicate one
direction of a serial port to only that message type. When the INTERFACEMODE command is used
to change the mode from the default, NOVATEL, you can no longer use NovAtel format messages.
If you wish to mix NovAtel format messages and RTCA, RTCM, RTCMV3 or CMR messages on the
same port, you can leave the INTERFACEMODE set to NOVATEL and log out variants of the
standard correction messages with a NovAtel header. ASCII or binary variants can be requested by
simply appending an "A" or "B" to the standard message name. For example on the base station:
interfacemode com2 novatel novatel
fix position 51.11358042 -114.04358013 1059.4105
log com2 rtcm1b ontime 2
Using the receiver in this mode consumes more CPU bandwidth than using the native differential
messages as shown in Section 3.3.1, Base Station Configuration on Page 35.
At the rover station you can leave the INTERFACEMODE default settings (interfacemode com2
novatel novatel). The rover receiver recognizes the default and uses the corrections it receives with a
NovAtel header.
The PSRDIFFSOURCE and RTKSOURCE commands set the station ID values which identify the
base stations from which to accept pseudorange or RTK corrections respectively. They are useful
commands when the rover station is receiving corrections from multiple base stations. Refer to the
GNSS Book for more information on SBAS, available from our Web site at:
All PSRDIFFSOURCE entries fall back to SBAS (even NONE) for backwards compatibility.
At the base station it is also possible to log out the contents of the standard corrections in a form that is
easier to read or process. These larger variants have the correction fields broken out into standard
types within the log, rather than compressed into bit fields. This can be useful if you wish to modify
the format of the corrections for a non-standard application, or if you wish to look at the corrections
for system debugging purposes. These variants have "DATA" as part of their names (for example,
RTCADATA1, RTCMDATA1, CMRDATAOBS, and more). Refer also to the OEMV Family
Firmware Reference Manual, which describes the various message formats in more detail.
Information on how to send multiple commands and log requests using DOS or Windows, can be
found on our Web site at
http://www.novatel.com/support/knowledgedb.htm