Ublox SARA-R5 Series, Руководство по системной интеграции

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SARA-R5 series - System integration manual
UBX-19041356 - R04 System description Page 25 of 118
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1.6.3 Module reset
SARA-R5 series modules can be gracefully reset (re-booted), triggering the storage of the current
parameter settings in the non-volatile memory of the module and performing a clean network detach
procedure, by:
• AT+CFUN=16 command (see SARA-R5 series AT commands manual [2] for further details).
An abrupt software reset of the modules, without storage of the current parameter in th e module’s
non-volatile memory and without proper network detach, can be triggered by:
• Forcing a low pulse on the RESET_N pin (normally high due to internal pull-up) for a valid time
period (see the SARA-R5 series data sheet [1] ).
☞
If considered necessary, an abrupt software reset must be preferred to an abrupt emergency
hardware shutdown or an abrupt removal of the
VCC supply.
☞
In case of applications where an abrupt power removal cannot be avoided, it is recommended to
set the
RESET_N input line at the low logic level as soon as the power failure in the supply source
is detected, so that the under-voltage shutdown may be executed more safely since ~450 ms after
the falling edge at the
RESET_N input line.
As described in Figure 16 , the RESET_N input pin is directly connected to the processor core, with an
integrated active pull-up, in order to perform an abrupt software reset when asserted, excluding the
power management unit. Detailed electrical characteristics with voltages and timings are described
in the SARA-R5 series data sheet
[1] .
18
RESET_N
SARA-R5 series
Baseband processor
Reset
Figure 16: SARA-R5 series RESET_N input equivalent circuit description