Vanguard 3000 Multicarrier Cellular Data Modem & IP Router PN 134732-VG3000 Rev. D| Page 108
Receive an indication generated by the Vanguard 3000
(1) Vanguard 3000 sends indication (NMEA msg: ALR)
[manager application] <-------- alarm -----(1)---- [Vanguard 3000]
Alarms and Indications
Alarms
Alarms are abnormal conditions or faults declared by the Vanguard 3000.
The manager is able to acknowledge alarms to stop their repeated generation.
Reporting
Alarms are reported continually at GPS AVL reporting rate until acknowledged by the manager or until the alarm root
cause disappears.
Upon original assertion, alarms force the immediate generation of an alarm report
Indications
Indication messages are unacknowledged.
Alarm return-to-normal
The Vanguard 3000 generates an indication message when the root cause of a previously-declared alarm has
disappeared.
Informational messages
The Vanguard 3000 generates an indication message when a non-alarm, informational event is detected (for example,
power-up boot sequence has completed).
A single informational message is currently supported by the Vanguard 3000: vehicle power-up (corresponds to initial
detection of ignition sense).
Position Fix
Immediately following an alarm or indication message, the Vanguard 3000 sends a $GPRMC message followed by a
$GPVTG message to help track the vehicle.
The $GPRMC and $GPVTG messages are sent in the same UDP datagram (when UDP is used) or in the same TCP
datagram (when TCP is used) as the alarm or indication message.
Multiple Alarms or Indications Reports
The Vanguard 3000 is able to send up to twelve (12) alarm and/or indication messages in a single transmission.
Each alarm or indication is sent using its own ALR message.
The GPS position fix is appended only after the last ALR message.
Example:
