DSUB IDC Name Dir Description
1 1 CD IN Carrier Detect
2 3 RXD IN Receive Data
3 5 TXD OUT Transmit Data
4 7 DTR OUT Data Terminal Ready
5 9 GND - System Ground
6 2 DSR IN Data Set Ready
7 4 RTS OUT Request to Send
8 6 CTS IN Clear to Send
9 8 RI IN Ring Indicator