Simultaneous voice and asynchronous data telephone

• US 4,593,389 A
• Filed: 06/28/1984
• Issued: 06/03/1986
• Est. Priority Date: 06/28/1984
• Status: Expired due to Term

• Current Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Wurzburg, Henry, Kelley, Stephen H.
• Primary Examiner(s): Olms, Douglas W.
• Application Number:
  US06/625,871
• Time in Patent Office: 705 Days
• Field of Search: 370/110.1, 179/2 DP
• US Class Current: 370/524
• CPC Class Codes: H04M 11/068 using time division multiplex techniques; integrated services digital networks H04Q11/0428
• CPC Class Codes: H04M 19/08 with current supply sources at the substations generating ringing current H04M19/04

Abstract

A telephone which can receive and transmit voice and asynchronous data simultaneously is provided. A signalling circuit provides signals indicating the request for a communication link or requesting a communication link to a predetermined location. A transceiver circuit synchronously receives and transmits frames of digital data bits representing data, voice and signalling information. A voice digitizer circuit converts the received frames of digital bits to an analog output and converts a received voice signal to a digital voice output. An interface circuit is used to interface between an asynchronous data source and the synchronous transceiver circuit. The telephone is line powered by utilizing D.C. isolating transformers to power both voice and data circuitry.

Claims

1. A digital telephone for providing simultaneous voice and asynchronous data communication via a two conductor communication channel, comprising:

signalling means for providing a first signal indicating the receipt of a communication link request and a second signal indicating a request for a communication link to a predetermined destination;

transceiver means coupled to both the two conductor communication channel and the signalling means, for synchronously receiving from the two conductor communication channel frames of digital bits, predetermined ones of which each contain data, voice and signalling information, and synchronously tansmitting frames of digital bits from the telephone to the predetermined destination via the two conductor communication channel;

voice digitizing means coupled to both the transceiver means and the signalling means, for converting the voice information portion of the received frames of digital bits to an analog output, and for receiving and converting an analog voice signal to a digital voice output which is coupled to the transceiver means for transmission;

asynchronous data inteface means coupled to the transceiver means, for receiving a receive portion of digital data from the transceiver means and providing the receive portion of data in asynchronous form at an output, and for asynchronously receiving a transmit portion of digital data and providing the transmit portion of data to the transceiver means while maintaining synchronization with the transceiver means;

switching power supply means having an input coupled to the two conductor communication channel, and an output, for converting D.C. power received from the two conductor communication channel to a regulated D.C. voltage for line powering the telephone set;

first isolation means coupled to the output of the switching power supply means, for converting D.C. power received from the communication channel to an isolated, regulated D.C. voltage for line powering the telephone set; and

second isolation means coupled between the transceiver means and the two conductor communication channel, for electrically isolating D.C. voltage potentials which may be coupled to the communication channel at both the telephone set and a remote location.

2. The digital telephone set of claim 1 wherein the transceivers means is coupled to the voice digitizing means via a 64 K bits/second communication channel, said transceiver means is coupled to the signalling means via an 8 k bits/second communication channel, and said transceiver means is coupled to the asynchronous data interface means via a second 8 K bits/second communication channel.

3. A simultaneous voice and asynchronous data telephone, comprising:

synchronous transceiver means coupled to a synchronous communication channel, for synchronously receiving frames of digital bits, each frame containing data, voice and signalling information, and synchronously transmitting frames of the bits to a predetermined destination;

signalling means coupled to the transceiver means via a first channel means, for receiving a ring signal indicating the receipt of a communication link request, and for coupling a call signal to the transceiver means indicating the request for a communication link with the predetermined destination;

voice digitizing means coupled to the transceiver means via a second channel means, for converting the voice information portion of the received frames of digital bits to an analog output, and for receiving and converting an analog voice signal to a digital voice output;

data interface means coupled to the transceiver means via a third channel means, for asynchronously receiving data in start/stop format and providing the data to the transceiver means while maintaining synchronization, and for receiving data from the transceiver means and asynchronously providing the data at an output, wherein the second channel operates at a higher communication rate than the first and third channels;

switching power supply means having an input coupled to the synchronous communication channel, and an output, for converting D.C. power received from the synchronous communication channel to a regulated D.C. voltage for line powering the telephone;

first isolation means coupled to the output of the switching power supply means, for converting D.C. power received from the communication channel to an isolated, regulated D.C. voltage for line powering the telephone; and

second isolation means coupled between the transceiver means and the communication channel, for electrically isolating substantially equal D.C. voltage potentials which may be coupled to the communication channel at both the telephone set and a remote location.

4. The telephone of claim 3 wherein the second channel operates a substantially 64K bits/second and the first and third channels each operate at substantially 8K bits/second.