Kantronics KAM 98, Руководство пользователя

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+ Note: You do NOT have to change the interface command (INTface) to GPS
since the GPS device is not attached to the RS-232 port in this tracker configura-
tion. Second, it is necessary to configure jumper J9 to the center pin and pin 2.
This jumper setting routes the signal coming from pin 3 into the processor.
3. With the tracker set up and running - Magellan feeding the firmware port of
the KAM’98 - with a computer attached to the RS-232 serial port, with a basic
terminal program running, and with the packet MONITOR command and moni-
tor transmission (MXMIT) command on, beaconed RMC strings look like this:
W0XI>GPS: <UI>:
$GPRMC, 200257,A,3858.07,N,09518.09,W,00.0,000.0,040798,04,E*5D.
Time and data accuracy
Data and time accuracy for GPS tracker operations are improved with the
KAM’98. The firmware features the option of clearing of the location text buffers
after each beacon and the verification of checksums of the fix strings if they were
included in the NMEA-0183 strings received.
With the CLEAR option in the beacon location text (BLT) command, one has the
option of not beaconing if a new NMEA string is not received. If one was not re-
ceived but the location text buffer is still full, not CLEARED after the last bea-
con, “old” data will be beaconed. With the clear feature only fresh and valid data
is beaconed. This is optional, of course, as in some applications one might want
to beacon the last location known.
With the gpstime command (GPSTIME), one has the option of not setting the
KAM’98 clock unless a fresh string has been received that has a correct
checksum. Using this option in conjunction with the clear option for the location
text buffers, one can be assured that a beacon will not go out that does not have a
satellite based updated UTC time stamp.
GPS NMEA Interfacing Capability Packet Modes of Operation
KAM’98 v 8.3 197 User’s Guide