User's Manual

page 40/51
HiAll
NC
User Manual 2012/06/28
6.4 MODULE POWER OFF
AT command “AT*PSCPOF” allows for correct power-off of the HiAll
NC
module.
In case of necessary the module can be powered off by controlling the power supply. This can be used for
example when the system freezes and no reset line is connected to the HiAll
NC
. In this case the only way to get
the control back over the module is to switch off the power line. If the system is on a battery, it is wise to have a
control of the power supply by a GPIO with for example the following schematic.
Figure 26: Power supply command by a GPIO

This kind of schematic could also be used to save few micro amperes in case of need. As the module has
a drain current of up to 56µA, this kind of function could lower it to the current through R4.
These, are the behaviours of the VGPIO and the CTS signal during the power off sequence.
Figure 27: Power OFF sequence for POK_IN, VGPIO and CTS
POK_IN is low
VGPIO
Module is ON
Module is OFF
Typ 2 seconds
AT*PSCPOF
CTS
POK_IN is high