TrackingTheWorld WorldTracker AVL, User Manual

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Serial port data sending using the GSM Modem:
Serial port data sending allows any external device to use the tracking units as communication interface. As
the tracking unit has the TCP/IP protocol build in the external device does not require the protocol to send
and receive data using the Internet to or from any location in the world.
Simple ‘AT’ commands are used for all communication.
Serial port data sending:
Tracking unit must have credits to access the modem using the serial port for SMS and GPRS mode(s).
Send "S". (Capital "S")
Wait for "OK+<mode - 1 byte>"
(mode is 0 when in SMS only mode and 1 if in SMS and GPRS mode)
Then send 4 digit pa CR ($0D).
Wait for “>” + CR($0D) + LF($0A).
The serial port has now ‘direct’ access to the GSM modem. Baud speed is set at 9600 and cannot be
changed. Only ‘AT’ commands are allowed, no connection to the internet using dial-up is allowed on this
port.
The tracking unit will monitor the port for data communication.
Type ‘AT COMSTOP’ or ‘at comstop’ to disconnect.
Type ‘at status’ or ‘AT STATUS’
This command will report current status and GPS location.
Example:
< Connected using ‘S’ command>
>
at status
< CR>
05*850,000,L001,A,2459.3640,N,12125.2958,E,000.0,224.8,00.8,07:47:26 09-09-05,9.00,D3,0,C4,1
When connected using the ‘Serial port data sending’ the GPS module is automatically powered on if the
tracking unit is in ‘sleep’ mode.
If no data is send (from the serial port to the modem) for more then 60 seconds the port will automatic
disconnect.
During connection the tracking unit cannot send or process any data.
Please note:
In SMS only mode the unit will send all data using SMS. In SMS and GPRS mode the unit will send all data
using GPRS.
The unit still processes SMS messages when connected to the GPRS network. The unit can process and
send SMS messages without disconnecting from the GPRS network.
Priority of Messages:
As your tracking system processes many inputs and outputs there are several outputs and inputs that have
priority above others.
In general:
Panic Button – First Priority
Alarm input – Second Priority
All others have the same priority, but reporting of the activation may depend on what input has activated first
if several inputs are activated at the same time.
This priority setup may delay messages that have less priority.
When changing operating mode from 'SMS Only' to 'SMS+GPRS' the current active commands are
completed first before changing operating mode.
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