User`s manual

Appendix A Pin Assignments 35
A.3 Isolated 5-wire RS-232/422/485 Serial
Port (COM3 ~ COM4)
Pin Assignments
Table A-3 Isolated 5-wire RS-232/422/485 serial port pin assignments
Pin 5-wire RS-232 Signal Name RS-422 Signal Name RS-485 Signal Name
1 RxD TxD+ DATA+
2 TxD TxD- DATA-
3 RTS RxD+ NC
4 CTS RxD- NC
5 GND GND GND
Note: NC represents “No Connection.”
RS-232/422/485 Selection
COM3 and COM4 support 5-wire RS-232, RS-422 or RS-485 interfaces,
and you can set corresponding jumpers to select serial ports as RS-232
or RS-422/485 interfaces shown in Table A-4.
The system detects RS-422 or RS-485 signals automatically in RS-422/
485 mode.
Table A-4: Jumpers to select 5-wire RS-232/422/485
Serial Port Corresponding jumper to select RS-232/422/485
COM3 JP4
COM4 JP5
COM3
1 2 3 4 5 1 2 3 4 5
COM4