CSI Wireless Vector Sensor, Справочное руководство

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Vector Sensor Reference Manual
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6.7.1 $GPMSK Beacon Tune Command
This command instructs the SBX beacon engine to tune to a specified frequency and automatically
select the correct MSK rate. When this command is sent through either Vector Sensor Port A or
B, it will automatically be routed to SBX. The resulting confirmation of this message will be
returned to the same port from which the command was sent. It has the following form.
$GPMSK,fff.f,F,mmm,M,n<CR><LF
Response.
$PCSI,ACK,GPMSK,fff.f,F,mmm,M,n<CR><LF>
Field Description
fff.f This field is the beacon frequency in kHz (283.5 to 325) and may be left null if
F This field selects the frequency selection mode, either manual “M” or automatic “A”
mmm This field is the MSK bit rate. If the following field is set to automatic MSK rate “A”,
this field can be left null
M Designates automatic MSK bit rate selection
n Period of output of performance status message, 0 to 100 seconds ($CRMSS)
When this message is acknowledged by the SBX, it will immediately tune to the frequency
specified and demodulate at the rate specified.
When the ‘n’ field is set to a non-zero value, the SBX will output the $CRMSS message at that
period through the serial port from which the SBX 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 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 Vector Sensor 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 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 may interrupt the flow of RTCM
data to the GPS receiver. Re-power the SBX to stop the output of the $CRMSS
message, or re-tune the beacon receiver with the ‘n’ field set to zero.
6.7.2 $PCSI,1 Beacon Status Command
This command is used to obtain $PCSI,CS0 beacon status data from the SBX beacon engine inside
the Vector Sensor. When this command is sent through either Port A or B, it will automatically be