[Hilo] How to get the indication when a CALL or SMS is coming while module is in data mode?
Answer: You can use RI signal as the indicator for a CALL or SMS when module is in data mode.
When you check the change of RI signal (From high to low level), please use +++ or toggle DTR signal to switch from data mode to command mode, then you can deal with the CALL or SMS.
Please set <AT&D1> or <AT&D2> to define the behavior of DTR drop.
Please set <AT+KRIC=3,1> to enable the RI indicator for call and SMS.
Please use to get back to data mode when you need.
For RI for incoming SMS, it’s a 1 second of pulse of high level.