User's Manual

M80 Hardware Design
M80_HD_V1.2 - 41 -
“AT+CFUN=1”.
For detailed information about “AT+CFUN”, please refer to document [1].
3.6.2. SLEEP mode
The SLEEP mode is disabled in default software configuration. Customer’s application can enable
this mode by “AT+QSCLK=1”. On the other hand, the default setting is “AT+QSCLK=0” and in
this mode, the module can’t enter SLEEP mode.
When “AT+QSCLK=1” is sent to the module, customer’s application 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 is not accessible.
3.6.3. 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.
 Receiving an SMS from network wakes up module.
Note: DTR pin should be held low level during communication between the module and DTE.
3.7. Summary of state transitions
Table 9: 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
Sleep mode
Use PWRKEY pin, or
use EMERG_OFF pin
Pull DTR down or
incoming call or
SMS or GPRS