27
Startup
In its energized state, the GSM module
provides the supply voltage (VDD). VDD
ensures that the switching regulator
remains on, even when its closing condition
is lost (i.e. IGT_IN=low).
Explanation:
VBAT=operating voltage for the GSM
module
VDD=supply voltage from the module
Activation of the RS232 control line DTR
The TC35 Terminal can be switched on in the
same way as via IGT_IN by activating the
RS232 control line DTR (high signal).
Note
The TC35 Terminal is switched on
immediately using the recommended plug-
in power supply unit (see the above
explanation on startup).
Switching off /resetting theTerminal
The Terminal can be switched off in two
different ways:
Using a software command by means of
an AT command
A software shutdown via an AT command is
always advisable for a controlled shutdown
of the TC35 Terminal. In this case, the GSM
module signs off before the watchdog
condition results in the specific switching off
of the supply voltages.