User's Manual

M80 Hardware Design
M80_HD_V1.2 - 36 -
3.4.2.1. Power down module using the PWRKEY pin
Customer’s application can turn off the module by driving the PWRKEY to a low level voltage for
certain time. The power-down scenario is illustrated in Figure 9.
The power-down procedure causes the module to log off from the network and allows the software
to save important data before completely disconnecting the power supply, thus it is a safe way.
Before the completion of the power-down procedure, the module sends out the result code shown
below:
NORMAL POWER DOWN
Note: This result code does not appear when autobauding is active and DTE and DCE are not
correctly synchronized after start-up. The module is recommended to set a fixed baud rate.
After that moment, no further AT commands can be executed. Then the module enters the
POWER DOWN mode, only the RTC is still active. The POWER DOWN mode can also be
indicated by the STATUS pin, which is a low level voltage in this mode.
VBAT
PWRKEY
(INPUT)
STATUS
(OUTPUT)
EMERG_OFF
(INPUT)
Logout net about 2s to 12s
0.6s<Pulldown<1s
>160us
Figure 9: Timing of turning off the module
3.4.2.2. Power down module using AT command
Customer’s application can turn off the module via AT command “AT+QPOWD=1”. This
command will let the module to log off from the network and allow the software to save important
data before completely disconnecting the power supply, thus it is a safe way.
Before the completion of the power-down procedure the module sends out the result code shown