Data access arrangement with telephone interface

摘要

A data access arrangement (DAA) interface for alternately coupling a telephone set to a modem for operation in conjunction with and independent of the central office power supply line. The DAA interface provides an enhanced power supply to supply adequate power to the telephone set when the telephone set, or a computer coupled thereto, communicates with the modem independent of the central office line. Multiple relays are coordinated and controlled via an application program in communication with the modem which detects certain conditions representing incoming and outgoing telephone and data/facsimile calls, and commands the relays to respond to the conditions.