Company Confidential
23
Raveon Technologies Corp.
7.2. Position Transmission
When the
RF-7800W
transmits its position, it also reports other status information
such as voltage, input bits, temperature, velocity, and heading. All of these
parameters are compressed into a short data packet, and sent over the air in the
proper TDMA time slot. By default, each
RF-7800W
is assigned a time slot, based
upon its ID. ID 1 is slot 1, ID 2 is slot 2…
Position/status reporting happens in one of 2 intervals.
A)
At the
TXRATE
setting. This is the transmit frequency interval setting. The
user configures
TXRATE
to be shortest acceptable interval between reports.
The factory default is 10 seconds.
IDLERATE
is used as a slow-reporting rate for parked vehicles, vehicles that have
no active trigger inputs, no proximity alerts, and that the user has programmed
them to require a minimum movement distance before they will report.
7.3. GPS Position and Status Reception
When the
RF-7800W
receives a position report and status from another
RF-
7800W
, it will send this information out all connected telnet sessions that are in the
Communication Mode, formatted as configured with the
OUTPUT x
command. By
default, the output format is 0 (no position message sent out).
The position/status messages that the
RF-7800W
is able to send out of its
Communication Mode telnet sessions are:
None
No position message output.
Output 0
disable the device from outputting
any message when a position report is received.
$PRAVE
Raveon Position & Satus.
Output 1
This message is sent out of the
RF-
7800W
when it is operating in the
GPS 2
mode. This message is used by
third-party and PC applications for tracking location and status information.
*note: PRAVE is the format which messages are sent and received in the low
level hardware of the radio. A buffer is designated for holding these messages
and is polled by way of the GPSDATA command which returns in RGI format.
The command setting GPSAGAING can be used to set the amount of time to
allow for the buffer remaining stagnant before clearing the buffer and replacing
the parameters with 0s.
7.4. Security Keyphrase
The security KEYPHRASE programmed into every
RF-7800W
transponder
ensures that only
RF-7800W
transponders with the exact same security encryption
key phrase can receive position and status information. There are two versions of
keys that can be used.
