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Descriptions and non-contractual illustrations in this document are given as an indication only.
ERCO&GENER reserves the right to make any modifications.
7.7 WatchDog
The Hardware WatchDog function allows the surveillance of the modem software activity: the Software
management of the WatchDog must be implanted in the embedded application (Open AT).
If the software activity is interrupted, the component WatchDog starts a material Reset.
The WatchDog function is active only if the SIM card is present. That's why during a Firmware Update, it's
imperative to remove the SIM card.
Note: On the box label, the presence of the WD mark allows to identify Modems GenPro integrating this
hardware feature.
7.8 Audio
The audio interface is a standard interface for connecting a telephone handset.
Echo cancellation and noise reduction features are also available to improve the audio quality in hands-free
applications.
ERCO & GENER recommend the use of the following cable : DATA/AUDIO Sub D 9pts Fem / Sub HD 15pts
Male / RJ9 (order code 4404000205) and a telephone handset (order code 3153400000).
Table : Pin identification
Pin name
SUBD 9 F pin number
SUBD 15 M-HD pin number
DCD/Buzzer 1
1
RXD 2
6
TXD 3
2
DTR 4
8
GND 5
9
DSR 6
7
RTS 7
12
CTS 8
11
RI/3.8V 9
13
RJ9 pin number
Micro +
1
4
S
2
10
Speaker -
3
15
Micro -
4
5
7.8.1 Microphone
Differential microphone inputs are used to help reduce common–mode and TDMA noise. They are ESD
protected.
An electret type microphone (0.5 mA / 2 Volts) may be connected directly to these inputs allowing the
connexion of a telephone handset.
The microphone impedance is approximately 2 k
Ω
.