Product specifications

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For example, if you are communicating with the Crescent Vector Port B, and
wish to turn the GPGGA message on at an update rate of 5 Hz on Port A, the
following command would be used.
$JASC,GPGGA,5,OTHER<CR><LF>
If you wish to turn the GPGGA message on at 5 Hz on Port B, you would issue
the following command.
$JASC,GPGGA,5<CR><LF>
When turning a message on or off on ‘This’ port, you do not need to indicate
‘This’ at the end of the message. In contrast, when turning messages on or
off on Port C from Port A or Port B, you must use the following procedure. For
example, if you are communicating with the Crescent Vector on Port A and
wish to turn on the GLL NMEA message at 10 Hz on Port C, the following
command would be used.
$JASC,GPGLL,10,PORTC<CR><LF>
As with Port A and B, if you are communicating directly with Port C, you do
not need to indicate anything at the end of the message. Consult Chapter 6
for more information on NMEA messages.
S AVING THE C RESCENT V ECTOR C ONFIGURATION
Each time that you change the configuration of the Crescent Vector, you may wish to
save the new configuration so the receiver does not have to be reconfigured again
for the next power cycle.
To save the settings, issue the $JSAVE command and the receiver will record the
current configuration to non-volatile memory. The Crescent Vector will let you know
when the save process has been completed, which will take approximately five
seconds.
U SING P ORT D FOR RTCM I NPUT
The Crescent Vector has a port that’s been designed to accommodate externally
supplied corrections input according to the RTCM SC-104 protocol. Port D provides
this functionality although it’s been fixed to operate at a baud rate of 9600 (8 data
bits, no parity, and 1 stop bit – 8-N-1).
To use Port D of the Crescent Vector for correction input you must set the Crescent
Vector to operate in beacon differential mode using the following command:
$JDIFF,BEACON<CR><LF>
This command was designed to ‘turn on’ Port D differential operation in our products
since many use the Hemisphere GPS SBX beacon module, interfaced to Port D.
Although the following RTCM SC-104 message types don’t all contain differential
data, the Crescent Vector is compatible with them.