| Pin | Name | Dir | Description |
|---|---|---|---|
| 1 | DSR/RI | ![]() |
Data Set Ready / Ring Indicator |
| 2 | CD | ![]() |
Carrier Detect |
| 3 | DTR | ![]() |
Data Terminal Ready |
| 4 | GND | ![]() |
System Ground |
| 5 | RXD | ![]() |
Receive Data |
| 6 | TXD | ![]() |
Transmit Data |
| 7 | CTS | ![]() |
Clear to Send |
| 8 | RTS | ![]() |
Request to Send |
Note: Direction is DTE (Computer) relative DCE (Modem).
See also RS-232 (EIA-232) serial interface





