Macintosh Serial Port Pinouts - ZyXEL Communications Omni 288S User Manual

Macintosh Serial Port Pinouts

The following table shows the wiring of a modem Macintosh hardware
handshaking cable:
Mac Modem
Din 8 DB 25
1 4 & 20
2 5
3 2
4 7
5 3
6 -
7 8
8 7
Appendix C - Connector Pinouts
Description
DTR to RTS and DTR, Hardware Handshaking Out
CTS to CTS, Hardware Handshaking In
TX- to TXD, Data sent
GND, Ground
RX- to RXD, Data received
not connected
GPI to CD, Carrier detected
GND, Ground, needed for RS-232 connections
C-2