Com Port Connector (Cn20); Com2 Rs-232/422/485 Setting (J9); Table 2-6: J9: Com2 Rs-232/422/485 Select - Advantech PCM-9550F User Manual

2.18 COM port connector (CN20)

The PCM-9550F/FM/L provides four serial ports (COM1, 3, 4:
RS-232; COM2: RS-232/422/485) in one COM port connector.
The COM port connector is a 40-pin, dual-inline, male header. It
provides connections for serial devices (a mouse, etc.) or a
communication network. You can find the pin assignments for the
COM port connector in Appendix C.

2.18.1 COM2 RS-232/422/485 setting (J9)

COM2 can be configured to operate in RS-232, RS-422, or RS-
485 mode. This is done via J9.

Table 2-6: J9: COM2 RS-232/422/485 select

1-2
3-4
5-6
7-9
8-10
9-11
10-12
13-15
14-16
15-17
16-18
RS-232* RS-422 RS-485
Open Open
Open Closed
Closed Open
Closed Open
Closed Open
Open Closed
Open Closed
Closed Open
Closed Open
Open Closed
Open Closed
Closed
Open
Open
Open
Open
Closed
Closed
Open
Open
Closed
Closed
Chapter 2 Installation 27