u-blox ZED-F9P, Interface Description

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u-blox ZED-F9P Interface Description - Manual
Advance Information
NMEA Talker IDs continued
Configured GNSS Talker ID
BeiDou GB
Any combination of GNSS GN
4.1.3 Protocol Configuration
The NMEA protocol on u-blox receivers can be configured to the need of customer applications using
configuration items
CFG-NMEA-*
.
There are four NMEA standards supported. The default NMEA version is 4.10. Alternatively versions 4.00, 2.3,
and 2.1 can be enabled (for details on how this affects the output refer to section
Position Fix Flags in NMEA
Mode ).
NMEA defines satellite numbering systems for some, but not all GNSS (this is partly dependent on the NMEA
version). Satellite numbers for unsupported GNSS can be configured using configuration items
CFG-NMEA-*
.
Unknown satellite numbers are always reported as a null NMEA field (i.e. an empty string)
The NMEA specification indicates that the GGA message is GPS specific. However, u-blox receivers support the
output of a GGA message for each of the Talker IDs.
NMEA filtering flags
Parameter Description
Position filtering Enable to permit positions from failed or invalid fixes to be reported (with the "V"
status flag to indicate that the data is not valid).
Valid position filtering Enable to permit positions from invalid fixes to be reported (with the "V" status flag to
indicate that the data is not valid).
Time filtering Enable to permit the receiver's best knowledge of time to be output, even though it
might be wrong.
Date filtering Enable to permit the receiver's best knowledge of date to be output, even though it
might be wrong.
GPS-only filtering Enable to restrict output to only report GPS satellites.
Track filtering Enable to permit course over ground (COG) to be reported even when it would
otherwise be frozen.
NMEA flags
Parameter Description
Compatibility Mode Some older NMEA applications expect the NMEA output to be formatted in a specific
way, for example, they will only work if the latitude and longitude have exactly four
digits behind the decimal point. u-blox receivers offer a compatibility mode to support
these legacy applications.
Consideration Mode u-blox receivers use a sophisticated signal quality detection scheme, in order to produce
the best possible position output. This algorithm considers all SV measurements, and
may eventually decide to only use a subset thereof, if it improves the overall position
accuracy. If Consideration mode is enabled, all satellites, which were considered for
navigation, are communicated as being used for the position determination. If
Consideration Mode is disabled, only those satellites which after the consideration step
remained in the position output are marked as being used.
Limit82 Mode Enabling this mode will limit the NMEA sentence length to a maximum of 82 characters.
UBX-18010854 - R04 Advance Information Page 7 of 259