KR950002754B1 - Interface circuit of keyphone system - Google Patents

Abstract

The circuit includes; a plurality of hierarchy 1 functions for decoding a signal from a digital multifunction telephone and outputting it to a PCM highway interrupt, and for encoding a signal received from the PCM highway interrupt; the PCM highway interrupt for outputting a signal from the hierarchy 1 functions to a PCM highway; a plurality of hierarchy 2 functions for outputting a control signal from a processor to the hierarchy 1 function; a PLL for outputting a signal to the hierarchy 1 function; a local interface bus interrupt for outputting a control signal from a private exchange to the processor and hierarchy 2 function; and a monitor for displaying the operation state, the monitor being connected to the processor.

Description

Digital Multifunction Telephone Interface Circuit

1 shows a digital multifunction telephone connected to a digital multifunction telephone interface circuit.

2 is a schematic diagram of a digital multifunction telephone interface circuit.

3 is a block diagram of a multi-function telephone interface circuit according to the present invention.

4 is a diagram for explaining signal transmission between a multifunction telephone interface circuit and a multifunction telephone according to the present invention;

* Explanation of symbols for main parts of the drawings

1: private exchange 2: digital multifunction telephone interface circuit

4: digital multifunction telephone 5: transceiver

6 control unit 10 layer 1 functional unit

11: layer 2 function part 12: PCM highway interrupt part

13: PLL 14: LlB Interrupt Section

15 processor 16 monitor

T: trance

The present invention relates to a digital multifunction telephone interface circuit, and more particularly, to a digital multifunction telephone interface circuit capable of connecting a two-wire digital multifunction telephone and a private exchange.

Recently, digital multifunctional telephones capable of providing various services have been used. When the digital multifunction telephone is connected to a private exchange, as shown in FIG. 1, a digital multifunction telephone interface circuit 2 must be provided between the digital multifunction telephone 4 and the private exchange 1.

An object of the present invention is to provide a digital multifunction telephone interface circuit capable of connecting a two-wire digital multifunction telephone with a private exchange.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a schematic diagram of a digital multifunction telephone interface circuit. As can be seen from the figure, the digital multifunction telephone interface circuit 2 can be summarized and configured as a transformer (T), a transceiver (5) and a controller (6). The signal input from the digital multifunction telephone 4 through the transformer T is decoded by the transmission / reception unit 5 so that a dual control signal is output to the control unit 6, and the control signal from the control unit 6 is a transmission / reception unit 5. Is encoded and output to the digital multifunction telephone 4 via the transformer T. That is, the control unit 6 performs a function of monitoring and controlling the communication state between the digital multifunction telephone 4 and the transceiver unit 5.

3 is a detailed block diagram of a digital multifunction telephone interface circuit according to the present invention. As can be seen from the figure, the digital multifunction telephone interface circuit 2 includes a plurality of transformers T, a plurality of layer one functional units 10, a plurality of layer two function units 11, and a PCM highway interrupt unit 12. ), A PLL (Phase Locked Loop) 13, a LIB (Local Interface Bus) interrupt unit 14, a processor unit 15, and a monitoring unit 16. In the drawing, only two transformers (T), one layer one function unit 10, and one layer two function unit 11 are shown, but in reality, eight are mounted on each one, so that eight digital multifunction telephones are provided in one interface circuit 2. Can be connected.

The layer 1 functional unit 10 decodes a signal input through a transformer (T) from one digital multifunction telephone 4 side, so that voice and data of the decoded signals (voice, control, and data) are transferred to the PCM highway interrupt unit ( 12) the voice and data outputted to the private exchange 1 side and switched at the private exchange 1 side are output to the layer 1 functional unit 10 through the PCM highway interrupt unit 12, where voice and data are output. It is encoded and output through the transformer T to another digital multifunction telephone 4 side. This means that a call path between two digital multifunction telephones 4 is connected and enables simultaneous communication of voice and data with one call line. The layer 2 function unit 11 converts a control signal of the signals (voice, data, and control) decoded by the layer 1 function unit 10 from serial to parallel and transfers the control signal to the processor unit l5 and the private exchange 1. On the contrary, the control signals from the private switch 1 and the processor unit 15 are converted from parallel to serial and transmitted to the layer 1 functional unit 10. That is, by exchanging control signals through the layer 2 function unit 11, the private exchange 1 side and the processor unit 15 can perform a check and control function of a call path between two digital multi-function telephones 4. . The PCM highway interrupter 12 performs a function of communicating voice and data between the digital multifunction telephone 4 and the private exchange 1 side at the timing assigned by each terminal. The PLL 13 is used to synchronize the synchronization between the private exchange 11 side and the digital multifunction telephone 4 (at the time of signal exchange). In practice, the PLL 13 receives a clock from the private exchange 1 side and synchronizes the synchronization with the layer 1 functional unit 10. Supply the clock to). The LIB interrupt unit 14 is composed of a buffer, a programmable array logic (PAL), and a clock circuit, and controls the control signal inputted from the private exchange 1 side through the LIB (Local Interface Bus) and the processor unit 15 side. It outputs to the 2 function part 11, and outputs the control signal input from the processor part 15 side and the layer 2 function part 11 to the private exchange 1 side via LlB. The monitoring unit 16 displays the operation state of the digital multifunction telephone interface circuit 2.

4 is a diagram illustrating an example of a method of encoding and decoding a signal occurring in the layer / function unit 10. Including the actual digital multi-function interface (2) internal communication, the signal communication between the private switch 1 (1), all signals are communicated in the form of (A), the signal between the digital multi-function telephone interface circuit (2) and the digital multi-function phone (4) The communication is performed by converting the layer 1 functional unit 10 into a biphase (D) form. In other words, the digital multifunction telephone interface circuit 2 adopts the dual phase method in the signal coding method, and the signal is transmitted and received on the line of the actual digital multifunction telephone 4 in the same waveform as (E). (B) (C) is converted from (A) to (D) and is shown for clarity. When a signal such as (E) of FIG. 4 is input from the digital multifunction telephone 4 to the layer 1 functional unit 10 through a transformer (T), it is decoded into a signal such as (D) of FIG. 4 and the PCM highway interrupt unit A signal such as (D) of FIG. 4 inputted from (12) and the layer 2 functional section 11 is encoded into a signal such as (E) of FIG. 4 by the layer 1 functional section 10, and the digital multifunction telephone 4 Output to the side.

As described above, the digital multifunction telephone interface circuit according to the present invention has the effect of smoothly connecting the two-wire digital multifunction telephone 4 using the existing telephone line to the existing all-electric private exchange.

Claims (1)

A plurality of transformers (T) for matching input and output signals; The digital multifunction telephone 4 decodes the signal input through the transformer T and outputs it to the PCM highway interrupt unit 12, and encodes the signal input from the PCM highway interrupt unit 12 to transmit the transformer T. A plurality of hierarchical one function units 10 for outputting to a side); The PCM highway interrupt unit 12 outputs the signal from the layer 1 function unit 10 to the PCM highway side in timing, and outputs the signal from the PCM highway side to the layer 1 function unit 10 in timing. And a control signal from the processor unit 15 to the layer 1 functional unit 10, and outputs a control signal of the signals (voice, data, control) from the layer 1 functional unit 10 to the processor unit. A plurality of layer 2 functional units 11 outputted to the (15) side; A PLL (13) for synchronizing clocks with the clock signal from the private switch (1) and outputting the same to the layer 1 functional section (10); The control signal input from the private exchange 1 side through the LIB (Local Interface Bus) is outputted to the processor unit 15 side and the layer 2 function unit 11, and the processor unit 15 and the layer 2 function. An L1B interrupt section 14 for outputting a control signal from the section 11 to the LIB side; The control signal from the LIB interrupt unit 14 is processed and output to the layer 2 functional unit 11, and the control signal from the layer 2 function unit 11 is processed and output to the LIB interrupt unit 14. The processor unit 15; And a monitoring unit (16) connected to said processor unit (15) to display an operation state.