connector wiring scheme
25 pin D-SUB female
connector
25 pin D-SUB male
connector
| Pin | Name | Dir | Description |
|---|---|---|---|
| 1 | GND | - | Ground |
| 2 | TXD- | OUT | Transmit Data |
| 3 | RXD- | IN | Receive Data |
| 4 | RTS | OUT | Request To Send |
| 5 | CTS | IN | Clear To Send |
| 6 | DSR | IN | Data Set Ready |
| 7 | GND | - | Ground |
| 8 | DCD | OUT | Data Carrier Detect |
| 20 | DTR- | OUT | Data Terminal Ready |
| 22 | RING | IN | ? |
Notes
- Direction is Printer relative Computer.