PROFIBUS DP uses a DB9 connector for field device communication at up to 12 Mbps. Widely used in Siemens PLC systems for sensors and actuators.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | Shield | Cable shield | GND |
| 3 | B-Line | RxD/TxD positive | BUS |
| 4 | CNTR-P | RTS control signal | I/O |
| 5 | DGND | Data ground | GND |
| 6 | VP | Positive for termination | PWR |
| 8 | A-Line | RxD/TxD negative | BUS |