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2. General Description
The Tracker can be operated by standard SMS messages from a mobile phone, or via
GPRS internet connection. With a standard SMS message, the GPS position data can
be requested and will then be sent back to the requested user mobile phone via a reply
SMS from the Tracker. The number and the time sequence of these GPS data blocks
and other parameters are fully programmable by an instruction SMS.
2.1 Data Format of SMS Command Messages:
The data has to comply with an exact format able to be read by the tracker module.
The format is: [Password]-[mode]-[Sub-Group1]-[Sub-Group2]
Password : Factory default password (security code) is 1234
Mode : Select the operating mode. This can be a Direct command,
Set-up command, or a Recall command.
Sub-Group1 : ON / OFF commands; or Set-up (Initialization) or Request group.
Sub-Group2 : Parameters of the set-up group. Information like Telephone
numbers, setting string of T and C mode, data format for GPS
information (DMS,Google,Ddec) etc.
2.2 Geo-Fence feature:
The tracker has a “geo-fencing” feature. If activated, the instructed party will receive a
SMS when the Tracker unit exits and enters the set boundary area.
2.3 Battery Low alert:
When the Internal battery is nearly discharged and reaches a predetermined low voltage
level, the charge LED starts blinking and later a SMS message will be sent to indicate a
“Battery Low” situation. (Please note that this feature is turned OFF by Default. It will have
to be activated with the message 1234-BATLOW-ON, if required.)
2.4 No GPS data:
If no GPS data can be retrieved from the GPS receiver the unit will transmit the current
GSM tower location “Node” information.
2.5 Last valid GPS position data:
The “LAST” valid GPS position data can be recalled via SMS message. This may be a
position of quite some time ago if powersave mode is used.