GSM/GPRS Module
M85 Hardware Design
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For detailed information about ―AT+CFUN‖, please refer to the
document [1]
.
3.5.2. SLEEP Mode
The SLEEP mode is disabled by default. You can enable it by ―AT+QSCLK=1‖. On the other hand, the
default setting is ―AT+QSCLK=0‖ and in this mode, the module cannot enter SLEEP mode.
When the module is set by the command with ―AT+QSCLK=1‖, you can control the module to enter or exit
from the SLEEP mode through pin DTR. When DTR is set to high level, and there is no on-air or hardware
interrupt such as GPIO interrupt or data on UART port, the module will enter SLEEP mode automatically.
In this mode, the module can still receive voice, SMS or GPRS paging from network, but the UART port
does not work.
3.5.3. Wake Up Module From SLEEP Mode
When the module is in the SLEEP mode, the following methods can wake up the module.
If the DTR Pin is set low, it would wake up the module from the SLEEP mode. The UART port will be
active within 20ms after DTR is changed to low level.
Receive a voice or data call from network wakes up module.
Receive an SMS from network wakes up module.
DTR pin should be held at low level during communication between the module and DTE.
3.5.4. Summary Of State Transition
Table 6: Summary of State Transition
Current mode
Next mode
Power Down
Normal Mode
Sleep Mode
Power down
Use PWRKEY
Normal mode
AT+QPOWD, use PWRKEY
pin, or use EMERG_OFF pin
Use AT command
―AT+QSCLK=1‖ and pull
DTR up
NOTES
Quectel
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