Serial connection ubuntu problem

[lipstick31]

Hello

I have a serial device in ubuntu which connection to the machine via serial cable and usb cable (for power supply i think)

I think that my device has not bidirectional support.

The device send some informations to the machine , but the machine cannot send same informations to the device

So , is there any way to set up this device with bidirectional support?

The only command i know is # dmesg |grep tty which shows me the device id.

Thanks in advance