BBxM UART2 which /dev/tty???

Hi everyone,

I 'm working on BBxM and have some trouble about UART2 to communicate with it.
I connect a Simcom 5218E device via UART2(RX_TX) and I tried to communicate with it but I could not.
I’m using microcom. microcom -s 460800 /dev/tty??? using this command to communicate with device. So I could not connect.

How to I know which UART in which device, /dev/tty???

My console is under image like this when it s running. ttyS2 .