CSI Wireless SBX-3, Reference Manual

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SBX-3 Reference Manual
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This section discusses the standard and proprietary NMEA 0183
commands accepted by the SBX-3.
5.6.1 Standard Commands
The following subsections describe the selection of valid standard
NMEA-0183 commands, and their responses.
5.6.1.1 Full Manual Tune Command ($GPMSK)
This command instructs the SBX-3 to tune to a specified frequency and
MSK rate and may be issued through either serial port. It has the
following form:
$GPMSK,fff.f,M,ddd,M,n<CR><LF>
Response:
$PCSI,ACK,GPMSK,fff.f,M,ddd,M,n<CR><LF>
Field Description
fff.f Frequency in kHz (283.5 to 325)
M Designates manual frequency selection
ddd MSK bit rate (100 or 200 bps)
M Designates manual MSK bit rate selection
n Output period of the performance status message, 0 to 100 seconds
($CRMSS)
When this message is acknowledged by the SBX-3, 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-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