DB9 RS232 pinout
| Pin | Signal | In/Out | Description |
|---|---|---|---|
| 1 | DCD | In | Data Carrier Detect |
| 2 | RxD | In | Receive Data |
| 3 | TxD | Out | Transmit Data |
| 4 | DTR | Out | Data Terminal Ready |
| 5 | GND | - | Ground |
| 6 | DSR | In | Data Set Ready |
| 7 | RTS | Out | Request To Send |
| 8 | CTS | In | Clear To Send |
| 9 | RI | In | Ring Indicator |
db9 pin configuration