DB9 to DB25 Conversion Pinout
Pinout and COM Port Summary Card
| EIA-232-E (RS-232) Function |
| EIA-530 Function | PIN # DB-25 | TO DTE | TO DCE | |||||
| Shield | 1 | Shield | 1 | |||||||
| Transmit Data (TD) | 2 | 3 |
| 2 14 | > | |||||
| Receive Data (RD) | 3 | 2 |
| 3 16 | < | |||||
| Request To Send (RTS) | 4 | 7 |
| 4 19 | > | |||||
| Clear To Send (CTS) | 5 | 8 |
| 5 13 | < | |||||
| DCE Ready (DSR) | 6 | 6 |
| 6 22 | < | |||||
| Signal Ground (SG) | 7 | 5 |
| 7 | ||||||
| Received Line Signal Detector (DCD) | 8 | 1 |
| 8 10 | < | |||||
| DTE Ready (DTR) | 20 | 4 |
| 20 23 | > | |||||
| Ring Indicator | 22 | 9 | N/A | ----- | ||||||
This table is from http://www.bb-elec.com/Learning-Center/All-White-Papers/Serial/Quick-Reference-Card-RS-232-DB9-DB25-pinouts-level.aspx