User manual
ARK-1122 User Manual 18
2.5.7 COM Connector
ARK-1122C provides four D-sub 9-pin connectors, which offers two RS-232 serial
communication interface and two RS-232/422/485 serial communication interface.
Default setting is RS-232, and the mode of serial ports are controlled by relay IC. If
you would like to use RS-422/485, just need change the BIOS setting. You can find
detailed BIOS setting for serial ports in Chapter 3.
Figure 2.21 COM Port Connector
Table 2.12: COM Connector Pin Assignments
RS-232 RS-422 RS-485
Pin Signal Name Signal Name Signal Name
1 DCD Tx- DATA-
2 RxD Tx+ DATA+
3 TxD Rx+ NC
4 DTR Rx- NC
5 GND GND GND
6 DSR NC NC
7 RTS NC NC
8 CTS NC NC
9 RI NC NC
Note! NC means “No Connection”.