Apple Macintosh RS-422 Serial Connector Pinout
From AllPinouts
Connector pinout for: Apple Macintosh RS-422 Serial

8 PIN MINI-DIN FEMALE at the computer.
It's possible to connect RS-232 peripheral to the RS-422 port available on Macintosh computers. Use RXD- as RXD, TXD- as TXD, Ground RXD+, Leave TXD+ unconnected, GPi as CD.
| Pin | Name | Dir | Description |
|---|---|---|---|
| 1 | HSKo | OUT | Output Handshake |
| 2 | HSKi/CLK | IN | Input Handshake or External Clock |
| 3 | TXD- | OUT | Transmit Data (-) |
| 4 | GND | - | Ground |
| 5 | RXD- | IN | Receive Data (-) |
| 6 | TXD+ | OUT | Transmit Data (+) |
| 7 | GPi | IN | General Purpose Input |
| 8 | RXD+ | IN | Receive Data (+) |
Notes
- Direction is DTE (Computer) relative DCE (Modem)
- GPi is connected to SCC Data Carrier Detect (or to Receive/Transmit Clock if the VIA1 SYNC signal is high). Not connected on the Macintosh Plus, Classic, Classic II, LC, LC II or IIsi.
