Product Info

LTE Standard Module Series
EC21 Mini PCIe Hardware Design
EC21_Mini_PCIe_Hardware_Design 33 / 64
3.8.1. RI Signal
The RI signal can be used to wake up the host. When a URC returns, there will be the following behaviors
on the RI pin after executing AT+QCFG="risignaltype","physical" command.
High
Low
URC returns
120ms
Figure 10: RI Behavior
3.8.2. DTR Signal
The DTR signal supports sleep control function. Driving it to low level will wake up the module.
3.8.3. W_DISABLE# Signal
EC21 Mini PCIe provides a W_DISABLE# signal to disable or enable the RF function (GNSS not included)
W_DISABLE# signal function is disabled by default, and AT+QCFG=“airplanecontrol”,1 can be used to
enable this function. The W_DISABLE# pin is pulled up by default. Driving it to low level will let the module
enter airplane mode.
AT+CFUN can also be used to control the RF status, and the details are as follows:
Table 11: Airplane Mode Controlled by Hardware Method
Software method can be controlled by AT+CFUN, and has the same effect with W_DISABLE# signal
function, the details is as follows.
W_DISABLE# RF Function Status Module Operation Mode
High level RF enabled Normal mode
Low level RF disabled Airplane mode