"Serial type: Modem" mode is intended to be used when you need to establish dial up connection with the operator. This mode does not support AT commands, which are necessary for sending/reading SMS messages.
Instead of "Modem" mode, you can you "Console" mode. In this mode, your RS232/RS485 device will be able to connect to router's console and have full control of the router.
- Console login: root
- Console password: <your router's password>
Console command to send SMS message: 'gsmctl -S -s "<number> <text>" ', example: gsmctl -S -s "+37061234567 test message"
Console command to read SMS message: 'gsmctl -S -r <index>', example: gsmctl -S -r 1