RG500Q-EA to connect in Linux

Hi guys. I am trying to connect RG500Q-EA with our board in Linux. So I have installed USB driver in linux. Fortunately ttyUSB ports are created in /dev (ttyUSB0~ttyUSB4).
But when I type

microcom /dev/ttyUSB2

It responded below but I can’t type any command.
It seems the processor can’t communicate with the module.

connected to /dev/ttyS0
Escape character: Ctrl-
Type the escape character followed by c to get to the menu or q to quit

Anyone know about this??
Thank you.

Log in my system :

root@localhost:/# microcom /dev/ttyUSB2
connected to /dev/ttyS0
Escape character: Ctrl-
Type the escape character followed by c to get to the menu or q to quit

It was because I didn’t install USB driver properly. I’ve installed USB driver in Linux again. And now it’s working well.

Ok, wish you all the best.