20
COM1/COM2
: 4 x DB-9 COM ports with RS-232/422/485 signals (COM1-4 on the panel)
Pin
Signal
Pin
Signal
1
Data Carrier Detect (DCDA#)
6
Data Set Ready (DSRA#)
2
Receive Data (RXDA)
7
Request To Send (RTSA#)
3
Transmit Data (TXDA)
8
Clear To Send (CTSA#)
4
Data Terminal Ready (DTRA#)
9
Ring Indicator (RIA#)
5
GND
Pin Assignments for RS-232/422/485
Pin
RS-232
RS-422
RS-485
1
DCD
TX-
RTX-
2
RXD
TX+
RTX+
3
TXD
RX+
4
DTR
RX-
5
GND
6
DSR
7
RTS
8
CTS
9
RI
