Petrel User Manual 0.1
6
Petrel Operating Modes
Magnet Turn On/Off
The Petrel can be turned off using the magnet turn-off method any time, regardless of its current
state. When the Petrel unit is turned back on by the magnet, it will always start in Bluetooth
mode.
Bluetooth Mode
In this mode, Bluetooth is active and can be connected to with the Xeos Beacon Bluetooth app.
If no Bluetooth connection is made in 5 minutes, the unit will proceed to GPS Search Mode.
However, if a Bluetooth connection is established, the unit will stay in Bluetooth mode until 5
minutes after the most recent Bluetooth session has ended.
If the Petrel unit has exited Bluetooth mode before a Bluetooth connection could be made. The
magnet can be used to turn the unit off and then on again, to re-enter Bluetooth mode.
While in Bluetooth mode, both the AIS and GPS functionality of the unit are inactive. The unit will
not attempt to acquire a GPS lock and will not transmit or receive AIS messages.
GPS Search Mode
In GPS Search Mode, the Petrel unit will attempt to acquire a GPS lock. While in this mode, the
unit’s Bluetooth and AIS functionality are inactive.
If the attempt to acquire a GPS lock is successful, the unit will proceed to AIS Transmit Mode. If
the attempt fails, the unit will proceed to Underwater Mode. The decision to proceed to these
states is made according to the following decision criteria:
•
If a GPS lock is obtained, the unit will progress automatically to AIS Transmit Mode.
•
If any 90 second period passes without the unit observing a single GPS satellite above a
minimum threshold for signal integrity, the unit proceeds to Underwater Mode.
•
If 14 minutes pass without a GPS lock being obtained, the unit proceeds to Underwater
Mode. Note that this 14 minute timeout can be adjusted to be longer or shorter (GPS
Timeout).
