Microchip Technology GPS-2700, User Manual

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GPS-2700 User’s Guide
DS50003016A-page 42
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2020 Microchip Technology Inc.
systems that can be enabled. Configuration with invalid combinations of GNSS sys-
tems or GPS-2700 without uBlox 8 receiver will result in a Command Error response
and no change to the configuration.
The following example command will enable GPS, SBAS, Galileo and GLONASS all
concurrently:
GPS:SYST:SEL GPS SBAS GAL GLO
The following command will query the currently enabled GNSS systems:
GPS:SYST:SEL?
The GPS-2700 with uBlox 8 receiver will respond to the query with the list of enabled
GNSS systems such as:
GPS SBAS GAL GLO
GPS-2700 with firmware revision 0.75 and later and uBlox 8 GNSS receiver adds sup-
port for switching the talker ID mode between GP and GN for GGA, Microchip GGA,
RMC, and ZDA commands. See
Section 3.3.32 “GPS:NMEA:TALK <GP | GN>” for
detailed operations and restrictions on talker ID mode.
3.3.32 GPS:NMEA:TALK <GP | GN>
GPS-2700 with firmware revision 0.75 and later and uBlox 8 GNSS receiver adds sup-
port for switching the talker ID mode between GP and GN for GGA, Microchip GGA,
RMC, and ZDA commands.
This command has the following format and changed setting will be applied immedi-
ately to the GPS-2700, and is stored in NV memory:
GPS:NMEA:TALK <GP | GN>
The following command returns the NMEA talker ID mode stored in NV memory:
GPS:NMEA:TALK?
Sending command with invalid parameter or GPS-2700 without uBlox 8 receiver will
result in a Command Error response and no change to the configuration.
Several rules are applied when switching between GN and GP talker ID mode:
• The $GNxxx NMEA string is equivalent to corresponding $GPxxx NMEA string
except for the main talker ID $GN at the header.
• Sending GPS:NMEA:TALK GP command or any of the GPxxx commands will
change the talker ID mode to GP for all GGA, Microchip GGA, RMC, and ZDA
commands with any combination of GNSS systems enabled in
Section 3.3.31 “GPS:SYST:SEL [GPS | SBAS | QZSS | GAL | BD | GLO]” .
• If talker ID mode is GN and only one GNSS system is enabled (i.e.,
GPS|SBAS|QZSS only, or Galileo only, or GLONASS only, or BeiDou only), the
corresponding GNSS-specific talker ID listed in
Table 3-1 will be used.
• Sending GPS:NMEA:TALK GN command or any of the GNxxx commands will
change the talker ID mode to GN for all GGA, Microchip GGA, RMC, and ZDA
commands when more than one GNSS system is enabled.
• If talker ID mode is GP, the GSV command will only contain the satellite informa-
tion for GPS, SBAS, and QZSS only, if available. To include satellite info from
other GNSS systems in $GPGSV string, GPS:NMEA:SVN GN command dis-
cussed in
Section 3.3.33 “GPS:NMEA:SVN <GP | GN>” can be used.
The GPS:NMEA:TALK GP and GPxxx commands are useful for environment with poor
GPS reception with multiple concurrent GNSS systems enabled to output valid naviga-
tion and PVT data for GPS system. Please see Section 2.4.3 for details of merits in con-
current GNSS systems.