The followings are pin assignments for various connection options:
Opt8A/S
(DCE, DB25 Female)
2RxD
3TxD
4CTS
5RTS
6DTR
7GND
8DCD
20DSR
Opt8B/C
(DTE, DB25 Male)
2TxD
3RxD
4RTS
5CTS
6DSR
7GND
8DCD
20DTR
Opt8D
(DTE, DB9 Male)
1DCD
2RxD
3TxD
4DTR
5GND
6DSR
7RTS
8CTS
