Abstract: An improved communication system which allows data, voice, and/or other non-real-time and real-time data streams to be transferred from one station to another over a single telephone line with optimal use of the available bandwidth and with a transparency to data transferring processes such as in computer systems coupled to the station interface devices is disclosed. A local data+voice interface device accepts digital data at a data port, analog voice signals at a voice port, digitizes the voice signals, compresses them, packetizes both the digital data and the digital voice data, identifying for each packet the type of data contained therein, and transmits the packets to a remote data+voice interface device, which separates the packets by their identification, and reconstructs the separate voice and data streams.

Abstract: An improved data transfer system is provided to transfer game data over a telephone line with low delay even while a voice conversation is being transferred over the same telephone line. Voice data and game data are framed, in a modified HDLC framing scheme, with game data inserted, if necessary, into a frame which contains voice, so that the time needed to complete the frame is not added to the delay of the game data. The inserted game data need not be of a fixed length, as it is delimited within the voice data by an escape sequence not found in the voice data. The available bandwidth is efficiently used since frames of voice data are not necessarily sent during periods of silence and frames of game data or other data can be sent using the entire telephone line bandwidth. The data is framed at a point beyond the output of pre-existing games and data transfer programs, to allow for transparent insertion of voice into the frame stream.

Abstract: A system for reducing noise coupling in a mixed-signal IC includes a digital clock, an analog clock, and gating signal generator, and a gating circuit. The gating circuit receives a digital clock signal and the gating pulse to generate a gated digital clock signal having no pulses at a sampling edge of the analog clock signal to provide a "quiet time" for analog sampling.