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Telit TRIZIUM Product Description

80264ST10007a Rev. 4– 09/09/04

5.11 Jammed Detect & Report Extension

5.11.1 Overview

The Jammed Detect & Report feature allows a Telit TRIZIUM to detect the presence of a

disturbing device such as a Communication Jammer and give indication to the user and/or send a

report of that to the network.

This feature can be very important in alarm, security and safety applications that rely on the module

for the communications. In these applications, the presence of a Jammer device can compromise the

whole system reliability and functionality and therefore shall be recognized and reported either to

the local system for countermeasure actions or to the network providing remote actions.

An example scenario could be an intrusion detection system that uses the Telit TRIZIUM for

sending the alarm indication for example with an SMS to the system owner, and a thief incomes

using a Jammer to prevent any communication between the GSM module and the network.

In such a case, the Telit TRIZIUM detects the Jammer presence even before the break in and can

trigger an alarm siren, other communication devices (PSTN modem) or directly report this

condition to the network that can provide further security services for example sending SMS to the

owner or police.

5.11.2 Jammed Detect & Report custom AT commands

5.11.2.1 #JDR - Jammed Detect & Report

#JDR - Jammed Detect & Report

Execute command

Read command

AT#JDR?

Reports the current settings of the command, in the format:

#JDR: <mode>,<MNPL>,<DCMN>

Write command

AT#JDR = <mode>

[,<MNPL>,<DCMN>]

This command allows to control the Jammed Detect & Report feature.

The TRIZIUM can Detect if a communication Jammer is active in its range and give

indication to the user of this condition either on the serial line with an unsolicited

code or on a dedicated GPIO by rising it.

The TRIZIUM can also report to the network the Jammed status condition, even if

normal communications are inhibited by the Jammer, by using a unique message.

Parameter:

<mode> - behavior mode of the Jammed Detect & Report

0 - Jammed Detect & Report DISABLED (Default)

1 - the Jammed Detect is active and the Jammed condition is reported on pin

GPIO1/JDR

GPIO1/JDR LOW - Normal Operating Condition

GPIO1/JDR HIGH - Jammed Condition.

2 - the Jammed Detect is active and the Jammed condition is reported with a single

unsolicited code on serial line whose format is:

#JDR: JAMMED - Jammed condition detected

#JDR: OPERATIVE - Normal Operating condition restored.

Note: the #JDR: OPERATIVE code will show only after a jammed condition