Product Info

LTE Standard Module Series
EC21_Series_Hardware_Design
38
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The following figure shows the connection between the module and the host.
Figure 3: Sleep Mode Application via UART
 Driving the module’s DTR to low level will wake up the module.
 When module has a URC to report, RI signal will wake up the host. See Chapter 3.19 for details
about RI behaviors.
 AP_READY will detect the sleep state of the host (can be configured to high level or low level
detection). For more details about AT+QCFG="apready", see document [3].
3.5.1.2. USB Application with USB Remote Wakeup Function
If the host supports USB suspend/resume and remote wakeup functions, the following three
preconditions must be met to let the module enter sleep mode.

Execute AT+QSCLK=1 to enable sleep mode.

Ensure DTR is held at high level or keep it open.

The host’s USB bus, which is connected with the module’s USB interface, enters suspend state.
The following figure shows the connection between the module and the host.
Figure 4: Sleep Mode Application with USB Remote Wakeup