LC 475, Quadra 605, Performa 475 476: Serial Ports

These four Macintosh models have two serial ports, one for a printer and one for a modem. They ports are not identical.

* The printer port uses the standard 8-pin mini-DIN socket.

* The modem port uses a 9-pin mini-DIN socket.

Both sockets accept 8-pin plugs, but only the modem port accepts a 9-pin plug. Pin 9 on the modem connector provides +5V power from the ADB power supply. An attached modem should draw no more than 100mA from that pin. The total current available for all devices connected to the +5V supply for the ADB and the modem port is 500mA.