TrimTrac ProE Locator, Technical Manual

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TrimTrac ProE Locator Technical Manual v2.0e 84
is set “0=Disabled”. If the Motion Report Flag is set “1=Enabled” then motion will
cause a transition to STATUS. Expiration of IDLE Timeout, T1, causes a transition to
the STATUS state. The programmable IDLE Timeout, T1, is stored as seconds and is
typically on the order of 12 to 48 hours. There are also optional Anytime Polling
settings that allow the device to run the communications protocol stack during the
IDLE state to receive and process incoming messages.
FIX: The device attempts to fix a position until expiration of FIX Timeout, T2.
If a fix is achieved, the position is read by the application, the internal real-time clock
(RTC) is updated, and the TrimTrac ProE transitions to the STATUS state. If no
position fix is achieved prior to expiration of the FIX Timeout, T2, the TrimTrac
ProE transitions to the STATUS state with status of “no new fix”. The FIX Timeout,
T2, parameter is programmable and is stored as seconds and is typically on the order
of 3 to 5 minutes. If the device does not have a complete almanac, then it will keep
the GPS receiver operating in the background to collect it; however, almanac
collection will not delay the transition to the STATUS state once a GPS position fix is
obtained.
STATUS: The TrimTrac ProE retrieves the latest status information, constructs the
new appropriate message(s) and then transitions to the TRANSMIT state. In addition
to any position and associated information, the status information includes various
operational metrics such as conditional alerts, battery condition, battery change events
and other such information.
TRANSMIT: The device attempts to transmit alert, position and/or status
information to the server. First, the latest status information is combined with the
position information in messages per the TrimTrac Application Protocol. Such
messages are then sent to the GSM protocol stack to attempt transmission. If the
Motion Report Flag is set “1=Enabled” and the message was a Motion Report
Message then the TrimTrac ProE transitions back to the FIX state. If the message
was not a Motion Report Message then it does not transition to the FIX state, instead
if the transmission was successful, the TrimTrac ProE transitions to the QUERY
state. If the transmission fails, the TrimTrac ProE transitions to the DELAY state
unless the TriggerType was an IDLE timeout, in which case, it will transition back to
the IDLE state. The programmable TRANSMIT Timeout, T3, is stored in seconds
and is typically on the order of 1 to 5 minutes.
QUERY: The device waits to receive any requests from the server for a
programmable QUERY Timeout, T5. If any requests are received, they are processed
in order received and responses are sent. After expiration of the QUERY Timeout,
T5, the device transitions to the DELAY state if the TriggerType was motion, or to
IDLE state if the TriggerType was an IDLE timeout. The programmable QUERY
Timeout, T5 is stored as seconds and is typically on the order of 1 to 2 minutes.
Normally, the TrimTrac ProE can only receive and process Data messages sent from
the server application while in the QUERY state; however, it can receive messages
during any state if the appropriate polling capabilities are enabled. The unit can be
polled for information, including new or logged position information even if the GPS
receiver is actively computing new positions.