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Appendix A
A.3 Isolated RS-232/422/485 Ports
Pin Assignments
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.3: Isolated RS-232/422/485 Port Assigns
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.”
Table A.4: Jumpers to Select 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
