Abstract: A method and apparatus is provided within an interface to data terminal equipment for obtaining call progress information. The call progress information provides relevant data as to the progress of a call initiated by the data terminal equipment. The interface is designed to be used in a portion of the telephone network that lacks byte alignment. Such portions of the telephone network do not currently receive call progress tones. The interface is preferably a data service unit that includes a receiving means processor and a display means. The data service unit interprets signals sent from the DDA/OCU that encode the presence or absence of call progress tones sent from the destination node of an initiated call.

Abstract: An echo canceler is disabled by sending two signals to it or in the alternate, by sending a single signal. The two signals are bit shifted replicas of each other. The nature of the sequence of the bits within the signals assures that one of the two signals or in the alternate case, a single signal will disable the echo canceler. All of these signals are not necessarily comprised solely of tone at a predetermined frequency; rather they may merely have sufficient energy at a disabling frequency and sufficient signal noise ratio to disable the echo cancelers.

Abstract: A means is provided within an interface to data terminal equipment for obtaining call progress information. The call progress information provides relevant data as to the progress of a call initiated by the data terminal equipment. The interface is designed to be used in a portion of the telephone network that lacks byte alignment. Such portions of the telephone network do not currently receive call progress tones. The interface is preferably a data service unit that includes a receiving means processor and a display means. The data service unit interprets signals sent from the DDA/OCU that encode the progress or absence of call progress tones sent from the destination node of an initiated call.

Abstract: A method and apparatus is provided within an interface to data terminal equipment for obtaining call progress information. The call progress information provides relevant data as to the progress of a call initiated by the data terminal equipment. The interface is designed to be used in a portion of the telephone network that lacks byte alignment. Such portions of the telephone network do not currently receive call progress tones. The interface is preferably a data service unit that includes a receiving means processor and a display means. The data service unit interprets signals sent from the DDA/OCU that encode the presence or absence of call progress tones sent from the destination node of an initiated call.