User's Manual

GE866-DUAL Hardware User Guide
1VV0301051 Rev. 2 – 2014-04-07 7
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Reserved. Page 41 of 82
Mod. 0805 2011-07 Rev.2
8.1. Reset signal
Signal Function I/O pin
RESET* Phone reset I G4
RESET* is used to reset the GE866-QUAD. Whenever this signal
is pulled low, the GE866-QUAD is reset. When the device is
reset it stops any operation. After the release of the reset
GE866-QUAD is unconditionally shut down, without doing any
detach operation from the network where it is registered. This
behaviour is not a proper shut down because any GSM device is
requested to issue a detach request on turn off. For this
reason the Reset signal must not be used to normally shutting
down the device, but only as an emergency exit in the rare
case the device remains stuck waiting for some network
response.
The RESET* is internally controlled on start-up to achieve a
proper power-on reset sequence, so there's no need to control
this pin on start-up. It may only be used to reset a device
already on that is not responding to any command.
NOTE:
Do not use this signal to power OFF the GE866-QUAD. Use the
ON/OFF procedure to perform this function.
Signal Min Max
RESET* Input high 1.8V(NOTE1) 2.1V
RESET* Input low
0V
0
.2V
(NOTE1) this signal is internally pulled up so the pin can be
left floating if not used.
If unused, this signal may be left unconnected. If used, then
it must always be connected with an open collector transistor,
to permit to the internal circuitry the power on reset and
under voltage lockout functions.