UMTS/HSPA+ Module Series
UC200A-GL_Hardware_Design 24 / 78
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
Figure 3: Sleep Mode Application with USB Remote Wakeup
⚫
Sending data to the module through USB will wake up the module.
⚫
When the module has a URC to report, the module will send remote wakeup signals via USB bus to
wake up the host.
3.2.2.1. 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 kept open.
⚫
The host’s US
B bus, which is connected with the m
odule’s USB interface, enters
Suspend state.
The AP_READY is active low and the default state is high.
NOTE
