06-01-2017, 12:42 PM
Huh? A standard RS-232 port contains only a single serial port. There is no such thing as having multiple serial ports (port 0, port 1, etc.) contained within a DB-25 connector. This is why a pass-through is never needed. A RS-232 serial port can only have one device connected to it at a time (unlike RS-422 and RS-485).