An interface for connecting a local input device to a host, such as a telephone message receiving unit. The interface transfers data serially from the local input device to the telephone message receiving unit for print out or facsimile transmission thereby. Control of the interface is governed by a...http://www.google.de/patents/US5590339?utm_source=gb-gplus-sharePatent US5590339 - Input device interface with power connect state and serial data channel enabling power to the device from time to time
