CSI Wireless SBX-3, Reference Manual

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SBX-3 Reference Manual
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automatic mode, provided a valid beacon almanac
is present in receiver memory. Without a valid almanac, the beacon
receiver will perform a Global Search to identify candidate stations in
the area, followed by the acquisition phase of the initial search.
When the ‘n’ field is set to a non-zero value, the SBX-3 will output the
$CRMSS message at that period through the serial port from which the
SBX-3 was tuned. When issuing the tune command with a non-zero ‘n’
field through the secondary port, the periodic output of the $CRMSS
message will not impact the output of RTCM on the main port.
However, when tuning the SBX-3 with a non-zero ‘n’ field through the
primary port, the NMEA status message will be interspersed within the
RTCM data. Most GPS engines will not be able to filter the NMEA
message, causing the overall data to fail parity checking.
When power to the SBX-3 is removed and reapplied, the status output
interval resets to zero (no output). Section 5.7.1.2 discusses the
$CRMSS status message output by the SBX-3 as initiated using this
command.
Note – When tuning using the primary serial port, if the ‘n’ field
in this message is non-zero, the status data message output by the
SBX-3 may interrupt the flow of RTCM data to the GPS receiver.
Re-power the SBX-3 to stop the output of the $CRMSS message,
or re-tune the beacon receiver with the ‘n’ field set to zero.
5.6.2 Proprietary Commands
The following subsections describe the selection of CSI Wireless
proprietary NMEA-0183 formatted commands, and their responses.
5.6.2.1 Wipe Search Command ($PCSI,4)
The Wipe Search command instructs the SBX-3 to erase all
parameters within the beacon almanac and to initiate a new Global
Search to identify the beacon signals available for a particular area.