LTE Standard Module Series
EC200T Series Hardware Design
EC200T_Series_Hardware_Design 31 / 90
Figure 3: Sleep Mode Application with USB Remote Wakeup
Sending data to EC200T series through USB will wake up the module.
When EC200T series has a URC to report, the module will send remote wakeup signals via USB bus
so as to wake up the host.
3.5.1.3. USB Application with USB Suspend/Resume and MAIN_RI Wakeup Function
If the host supports USB Suspend/Resume, but does not support remote wakeup function, the MAIN_RI
signal is needed to wake up the host.
There are three preconditions to let the module enter sleep mode.
Execute
AT+QSCLK=1
to enable the sleep mode.
Ensure the MAIN_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.
USB_VBUS
USB_DP
USB_DM
AP_READY
VDD
USB_DP
USB_DM
GPIO
Module
Host
GND
GND
MAIN_RI
EINT
Figure 4: Sleep Mode Application with MAIN_RI
Sending data to EC200T series through USB will wake up the module.
When EC200T series has a URC to report, the URC will trigger the behavior of MAIN_RI pin.