T-RSC3 Serial Ports

[utr_brk]

T-RSC3 has one isolated RS-232 port, one isolated RS-485 port and one TTL serial port on 2x6 female header.
And there is also one virtual serial port which is used for programming etc, on the USB-C port.

I can access Virtual serial port as Serial, TTL serial port as Serial0.
But never achieved to access RS-232 and RS-485 ports.
I am using Arduino-IDE to program T-RSC3.

Any suggestions to use 232/485 ports will be much appeciated.

Best regards.
BT