Enable serial rs232 connection to external pc

Hello,

I have a Fidia F1 controller that I wish to connect by serial cable to a pc to transfer programs and DNC. How do I activate parameter TT0 for serial connection? I only have access to transfer from floppy drive and LN0 witch is I belive an old LAN connection type between dos pc s . The machine has 2 serial ports ,one in the front with 25 pins and one in the back of the controller with 9 pins that with DNC label.
I don't know much about this controllers.

Thanks in advance