KR920004154B1 - Analog/digital communication system - Google Patents

Abstract

a modem chip (23); a central control means (22) connected to the modem chip (23); an interface input/ output port (26) connected to both the modem chip (23) and the central control means (22); a relay circuit (25) connected to both the input/output port (26) and the modem chip (23); and a line matching circuit (24) connected to both the relay circuit (25) and the modem chip (23). The apparatus further includes: a ring tone detecting means (27) connected to both the line matching circuit (24) and the input/output port (26); a transmission detecting circuit (28) connected to both the line matching circuit (24) and the input/output port (26); and a speaker circuit (29) connected to the input/output port (26). The apparatus performs both audio and data communications through a single telephone line.

Description

Voice communication and data communication parallel method and apparatus

1 is a timing diagram with outgoing tones.

2 is a modem circuit diagram including a detection circuit.

3 is a flowchart of a receiving side according to the present invention.

4 is a diagram illustrating an operating procedure according to the present invention.

5 is a model diagram of the present invention applied to PC communication.

6 is a block diagram of the transmission tone detection unit of the present invention.

* Explanation of symbols for main parts of the drawings

20 modem device 27 ringtone detection unit

28: transmission tone detection unit 29: speaker circuit

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates generally to a method and apparatus for paralleling voice and data communications, and in particular, to a conventional modem circuit by adding a ring tone detection circuit, a dial tone detection circuit, and a speaker (or buzzer) having a circuit capable of producing sound. The present invention relates to a method and an apparatus for enabling simultaneous voice communication and data communication.

Due to the recent mass distribution of PCs, voice communication service and data communication service must coexist on a public telephone line in a normal home. Currently, most data communication equipment is not designed to coexist with voice communication. Therefore, after the first call is completed, the line must be restored and redialed again to enable the next voice call or data communication. Therefore, since the receiving side cannot know the status of the transmitting side, it is possible to receive at least one call. In order to prevent this, CCITT V.25 bis uses the calling tone recommended to distinguish between data communication and voice communication, so that the system can perform both voice and data communication.

The present invention makes it possible to distinguish whether a transmitting party is a person or a machine by using an existing source tone generating modem and a device that converts a single analog frequency into a digital waveform. Assuming that most modem communication currently has no outgoing tone, as shown in the first diagram, the modem generates a answering tone immediately upon hook-off and enters data communication. Therefore, when the machine dials, data communication is established. However, even if a person dials directly for a voice call, there is a disadvantage that a call is impossible because a machine answer is heard unconditionally.

In order to eliminate this shortcoming, the present invention uses a conventional modem chip that is already available to use an outgoing tone recommended as an option in CCITT V.25 bis, and has been widely used for accurate reception of this outgoing tone. Chip was used. And if the outgoing tone is not detected, it is possible to voice communication by informing the person that the voice call by generating a constant speaker sound in the step of not recovering the line.

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

2 is a block diagram of the present invention, which is composed of an existing modem apparatus 20, a ring tone detector 29, an outgoing tone detector 28, and a speaker circuit portion 29. As shown in FIG.

The existing modem device 20 includes an LED display circuit 21, a modem chip 23, a rotation matching circuit (DAA) 24, a relay circuit section 25, an interface I / O port 26, and a central control section 22. It consists of).

Referring to FIG. 2, in the existing modem circuit 20, a relay circuit section 25 connected to a line matching circuit (DAA) 24 is installed to generate a control signal at the interface input / output port 26 to generate a calling tone detection circuit section. (28) (e.g., XR2211) can be controlled. Circuits are attached to enable the speaker to operate when no tone is detected.

When the call is first initiated by the sender's modem, the exchange sends a ringtone to the other modem. At this time, the opposite modem detects the ring tone using the ring tone detection unit 27 and drives the switch and the relay by the control signal of the interface input / output port 26 (voltage amplification for driving the relay uses transistor amplification). Hook-off and connect the outgoing tone detection circuitry 28. Here, the ringtone detection unit 27 uses a commonly used ringtone detection circuit, and is configured using a photocoupler CN35 and a JK flip-flop, and whether or not ringtones are generated is transmitted to the central control unit 22 and the modem chip 23. Inform.

Thus, when a transmitting side generates a calling tone as a function of the sequence control of the existing modem, the calling tone is transmitted to the calling tone detecting circuit unit 28 of the other modem through the telephone line, and the receiving side is the moment when the line is hooked off. If the receiving side central control unit 22 checks the presence or absence of the outgoing tone for a predetermined time occurring in the outgoing tone detecting circuit unit 28 and sends out a predetermined signal to the speaker circuit 29 for a predetermined time, If this is detected, the hook-off line is switched to the modem receiver to control the central controller 22 to receive data according to the flowchart of FIG.

Referring to the flowchart of Fig. 3, when the ring tone is detected and the R1 signal is generated, the relay is operated so that the line is hooked off according to the program. After detecting outgoing tone with 1.5 ~ second silence time before outgoing tone generation, enter auto receive mode and start data communication.If outgoing tone is not detected even after more than 5 seconds, speaker sound It checks if a voice call is being made while ringing, and if a data communication is desired during the voice call, the user can enter the data communication mode.

Referring to FIG. 4, the method according to the present invention comprises: 1) a modem on the transmitting side receives a dialing number from a higher layer, recognizes a dialing tone, and transmits a digit. 2) the receiving side is determined by the exchange and transmits the ring tone to the receiving side and the ring back tone to the transmitting side; and 3) the receiving modem which recognizes the ring tone hooks off the hybrid circuit to perform outgoing tone detection. Beginning, the sender shall transmit a transmit tone of 0.5 to 7 sec after 1.5 to 2 sec of silence as recommended by CCITT V.25 bis if the ringback tone is recognized, and the receiver shall immediately disable the transmit tone detection circuit as soon as the line is hooked off. If the outgoing tone is not detected until 5 seconds has elapsed, determining that it is a voice call and transmitting a constant sound through the speaker (or buzzer); and 4) if the outgoing tone is detected, the receiving side sends out a response tone. The transmitting side starts the response tone detection, 5) the two modems of the transmitting side and the receiving side perform a training sequence for speed control, and then performs normal data communication; and 6) an application for terminating the communication. The modem may recover the circuit according to the circuit recovery command provided by the layer.

5 shows an example of the application of the present invention in a communications-ton processing system (CPS) which will serve as a PC communication adapter and a center function.

6 is a view illustrating an embodiment of a transmission tone detection unit in the configuration of the present invention.

In Figure 6, the transmission tone detection unit is constructed using the XR2211 chip and its peripheral circuit.

In the figure, R0, R1, Rx, Rd, and RL represent resistance, and CL, Cd, and Co represent capacitors.

As described above, according to the present invention, unnecessary transmission and reception are prevented by accurate classification of voice / data, and it is advantageous that both voice communication and data communication can be performed simultaneously in one telephone line.

Claims (2)

A transmitting side comprising a ring tone detection circuit, an outgoing tone detection circuit, and a speaker (or buzzer) having a sound generating circuit added to an existing modem circuit so that voice communication and data communication can be performed in parallel. The modem receives the dial number from the upper layer, recognizes the dial tone, and transmits a digit.The receiver determines the receiving side, and transmits the ring tone to the receiving side and the ring back tone to the transmitting side. When the recognized modem on the receiving side starts to detect outgoing tones, the transmitting side transmits 0.5 to 0.7sec of outgoing tone after 1.5 ~ 2sec mute according to the recommendation of CCITT V.25 bis when ring backtone is recognized. As soon as the hook-off is activated, the dial tone detection circuit is activated immediately, and if the dial tone is not detected until 5 seconds is exceeded, it is determined as a voice call, Transmitting a response tone, if the calling tone is detected, the receiving end transmits the response tone, the transmitting side starts detecting the response tone, and after the two modems of the transmitting side and the receiving side perform a training sequence for speed control, And performing a data communication and recovering a line by a modem according to a circuit recovery command provided by an application layer for terminating the communication. A modem chip 23, a central control means 22 connected to the modem chip 23, an interface input / output port 26 connected to the modem chip 23 and the central control means 22, and the input / output port 26 A modem device comprising a relay circuit 25 connected to a modem chip 23 and a line matching circuit 24 connected to the relay circuit 25 and the modem chip 23, wherein the line matching circuit 24 and Ring tone detection means 27 connected to an interface input / output port 26, outgoing tone detection means 28 connected to the DAA 24 and an interface input / output port 26, and a speaker circuit connected to the interface input / output port 26 ( 29) A voice communication and data communication parallel device, characterized in that consisting of.

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