fanuc 18 ta communication problem

[jeeprump]

hi,by wrong cable connected to communication port rs 232 we lost communication.There are to available ports on main fanuc 18 ta panel. We tried to use the second one by changing channel number I/O to 2 par 20 with no luck. Also we didn't noticed any output signals.Is any other parameters we suppose to chaged? Is it possible that interface module is defective? thanks for help.