GeoPort

GeoPort was an enhanced Mini-DIN-9 serial data port available on Apple's beige-era Power Macintosh computers.

Functionality
The serial ports were capable of LocalTalk speeds up to 230.4 kbps. Many early Macs typically had two Mini-DIN-8 serial ports, labeled for a printer and modem. The GeoPort specification adds a 9th pin to the serial port to supply 5 volts of DC power. A GeoPort is backwards-compatible with standard Mini-DIN-8 serial devices, but 9-pin peripherals cannot be plugged into an older 8-pin serial port.

Attaching a GeoPort Telecom Adapter to a GeoPort-ready serial port (labeled with a globe symbol on Pippin consoles) allows it to emulate and function as a (relatively) low-cost modem without an external power supply, at the expense of CPU overhead. The GeoPort's functionality was also integrated into Apple's proprietary Comm Slot II in some PowerPC-based Macintosh desktop computers, but has since been discontinued.

Telecom Adapter models
GeoPort Telecom Adapters shipped with varying modem connection speeds, and could be upgraded through software updates.
 * GeoPort Telecom Adapter M1694LL/B - 14.4 kilobaud (kbps)
 * GeoPort Telecom Adapter (II) M2117LL/A - 28.8 kilobaud (kbps)
 * GeoPort Telecom Adapter II M5438LL/A - 33.6 kilobaud (kbps)

Conventional modems on GeoPort
Some third party manufacturers, such as Global Village, also created conventional modems that could draw power from the 9th pin of GeoPort-equiped Macs to eliminate the need for a power supply, like Pippin modems.

Discontinuation
GeoPort and several other legacy technologies were eventually phased out by Apple, starting with Steve Jobs' introduction of the iMac G3 in May 1998.