Apple Communication Slot

The original Communication Slot standard was introduced in the Macintosh LC 575 and can be identified by the notch toward its rear.

In addition to the respective expansion bus pins, these slots also carried audio and serial lines.

Because the power and serial pins remained unchanged between the two slots, it was possible to design a universal modem card which could work in either.

[citation needed] Further, due to its unconventional architecture, the Performa 5200's printer port would be disabled if a network adapter was installed in the Communication Slot.

In addition, a modified Communication Slot II was present on the Power Macintosh G3 personality cards.