| Pin No. | RS-232 Signal | Direction | RS-485 Signal | Direction |
|---|---|---|---|---|
| 1 | DCD | input | SR | signal ref. |
| 2 | RxD | input | TxD B(+) | output |
| 3 | TxD | output | RxD B(+) | input |
| 4 | DTR | output | RTS B(+) | output |
| 5 | SG | signal gnd. | CTS B(+) | input |
| 6 | TxD A(-) | output | ||
| 7 | RTS | output | RxD A(-) | input |
| 8 | CTS | input | RTS A(-) | output |
| 9 | CTS A(-) | input |
Male DB-9 Connector (RS-232) Female DB-9 Connector (RS-485)
