Avalue ECM-CX700 - Manual (Page 13)

Quick Installation Guide
ECM-CX700 Series Quick Installation Guide 13
2.3.6 Serial Port 2 Connector in RS-232/422/485 Mode (JCOM2)
RS-232 Mode
Signal PIN PIN Signal
GND 10 9 RI
CTS 8 7 RTS
DSR 6 5 GND
DRT 4 3 TxD
RxD 2 1 DCD
RS-422 Mode
Signal PIN PIN Signal
GND 10 9 GND
RxD- 8 7 NC
TxD+ 6 5 GND
NC 4 3 NC
RxD+ 2 1 TxD-
RS-485 Mode
Signal PIN PIN Signal
GND 10 9 GND
NC 8 7 NC
DATA+ 6 5 GND
NC 4 3 NC
NC 2 1 DATA-