Apple Macintosh RS-422 connector

#Computer#Serial Interfaces#Apple

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.

8 pin MINI-DIN FEMALE connector pin-out & layout

8 pin MINI-DIN FEMALE connector  at the computer

PinNameDirDescription
1HSKo-->Output Handshake
2HSKi/CLK<--Input Handshake or External Clock
3TXD--->Transmit Data (-)
4GND---Ground
5RXD-<--Receive Data (-)
6TXD+-->Transmit Data (+)
7GPi<--General Purpose Input
8RXD+<--Receive Data (+)
On serial port A (modem), if the VIA1 SYNC signal is high, this input will be routed to the receive/transmit clock input of the SCC. This clock input supports high-speed synchronous devices. Pin 7 is not connected on the Macintosh Plus, LC, or IIsi. Note: Direction is DTE (Computer) relative DCE (Modem).

Apple LaserWriter Serial connector

Apple Macintosh Serial connector