XRS - Extensible Radio Specification XRS Technology: Interfacing radio with computers.
Antenna Switch

Antenna Switch

This plug-in makes it possible to switch antennas depending on the frequency the radio is tuned in. It requires a third-party (or do-it-yourself) external antenna relay which can be connected either to a serial or parallel port of your PC.

It can also launch a third-party application program if the radio is tuned to a particular frequency range.