TrimTrac ProE Locator, Техническое руководство

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TrimTrac ProE Locator Technical Manual v2.0e 41
Final consideration on how polling is enabled is that network operators from time
to time make changes on their networks that require power cycling of mobile
devices. The power reset occurs automatically on the TrimTrac ProE each time
the device cycles through the state machine in accordance with its default settings;
however, if Anytime Polling is set “2=OnDemand” or if the device is in
continuous motion and In-Motion Polling is set “1=Enabled”, the device may
never power cycle off. It is, therefore, recommended that Anytime Polling be set
“2=OnDemand” only when the application absolutely requires uninterrupted
communications and the device can be physically accessed to execute a power off
reset whenever such a need arises.
For those applications that require polling capabilites and the ability to recover
from network changes that require power cycling, it is recommended that In-
Motion Polling be set to “1=OnDemand” and Anytime Polling be set to “1=Duty
Cycled while in IDLE State”. Then set Polling Duty-Cycle Frequency, T19 to 60
seconds and set Polling Duty-Cycle On-Time, T20, to 3600 seconds. In so doing,
the server application can be in constant communication with the device while it
is in motion. While stationary, the device will keep the GSM modem active but
shut it off for 60 seconds after being on for an hour. This will achieve the power
reset that may be required from time to time as a result of changes on the network.
Query Hold Flag
The Query Hold Flag is seldom changed from its default configuration. In its
default 0=Disabled mode and assuming neither Anytime Polling nor In-Motion
Polling is enabled, if the device loses connection to the GSM network while in the
QUERY state, it will not attempt to re-establish connection again until the has
cycled back through the state machine and again re-enters the TRANSMIT or
QUERY states.
If the Query Hold Flag is set, then the device will attempt to re-establish
connection to the GSM network if connection to the GSM network was lost prior
to the expiration of the QUERY State Timeout, T5. It will attempt to re-establish
connection to the GSM network until the QUERY State Timeout, T5, has expired.
This may be of benefit to certain applications where no Polling is enabled and the
device may be expected to rapidly come into and exit GSM coverage and there is
a strong need to get messages transmitted as soon as possible. The Automatic
Message Log Dump feature described elsewhere, however, should suffice in most
applications.
Transmit Attempts
The number of transmit attempts is individually selectable for position reports,
status messages and alert messages. Each time the device has messages to be
transmitted, it enters the TRANSMIT State and assuming a GSM network is
available, it will make the specified number of transmit attempts until the