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LTE Standard Module Series
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3.2.2.2. 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.
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 5: Sleep Mode Application with MAIN_RI
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Sending data to the module through USB will wake up the module.
⚫
When the module has a URC to report, the URC will trigger the behavior of MAIN_RI pin.