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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
7.8 WatchDog
The Hardware WatchDog function allows the surveillance of the
GenPro 53e
software activity: the Software
management of the WatchDog is implanted in the embedded application by default. In the case of a
development (EGM) it must be implanted in the embedded application of the final customer.
If the software activity is interrupted, the WatchDog component starts a hardware Reset.
The WatchDog function is active only if the SIM card is present. That’s why, it is imperative to
remove the SIM card during a Firmware updating.
7.9 Audio
The audio interface is standard to connect an equipment like a telephone handset.
The modem contains the EGM standard library (see the documents
"EG_EGM_CL_xxx_yy" of ERCO &
GENER) in this case, the echo cancelation (see command
AT$MICAEC
) and noise reduction features are
also available to improve the audio quality in the case of free-hand applications. The command
AT$VSELECT
also allows the Handset selection.
(see paragraph 3.2.1.3 Audio connector ).
RJ9
Micro -
1
Speaker -
2
S
3
Micro +
4
7.9.1 Microphone inputs
The microphone inputs are assembled in differential to reduce the noise in common mode and the TDMA
noise.
They include the functionality for a microphone like Electret (0.5 mA and 2 Volts) and they are ESD
protected. This Electret microphone can be directly connected to these inputs allowing an easy connection to
a telephone handset.
The microphone impedance is around 36 k
Ω
.
The gain of the microphone inputs is internally adjusted by a differential amplifier and can be adjusted, if the
modem contains the EGM standard library (see the documents "EG_EGM_CL_xxx_yy" of ERCO & GENER)
using the command
AT+PREAM.
The amplifier has a gain of 25.6 dB and a Bias generator that supplies an
external tension of 2 or 2.5V for the microphone Bias.
