A two wire exchange system is disclosed that enables a gaming machine having one communication port to function as a gaming machine having a plurality of communication ports. The two-wire exchange system allows a gaming machine having only a single communication port to connect to two or more system hosts simultaneously. The two wire exchange system is an intelligent multiplexer that communicates using the same protocol as the system hosts to which it is connected. The two-wire exchange system has the ability to respond to a poll from the system host by indicating that the gaming machine is busy, and that the system host should poll the gaming machine again. This is provided to avoid and to prevent data collisions.