JPH05276280A - Telephone terminal equipment - Google Patents

Abstract

PURPOSE:To simultaneously transmit both voice data and communication data by providing an encoding means and a protocol converting means, multiplexing the voice data and the communication data by different bit length, and outputting both the data in each octet timing. CONSTITUTION:When the communication data are supplied from a personal computer side to a telephone terminal equipment 20, a CPU 3 writes the communication data through an SCC 6 in a transmission buffer 5a. When the buffer 5a is turned to a full state, the CPU 3 requests the transmission of the stored communication data, and the communication data are inputted to a multiplex and separator circuit 10. On the other hand, a voice speaking part supplies the voice data quantized by 8 bits to the circuit 10. The circuit 10 multiplexes the voice data for the upper 7 bits, and the communication data for the 1 bit in each octet timing, and transmits those data through a driver/receiver 11 to a B channel. Thus, the voice data in which an LSB 1 bit is removed are transmitted at a 56kbps transmission rate, and the communication data are transmitted at an 8kbps transmission rate.

Description

Detailed Description of the Invention

[0001]

This invention relates to ISDN (Integrat
The present invention relates to a telephone terminal device compatible with ed Services Digital Network).

[0002]

2. Description of the Related Art In recent years, ISDN (Service Integrated Digital Network) has been constructed to integrate various communication media such as voice, image, or data to provide various communication services, and accordingly, ISDN is connected. Various types of digital telephone terminals, compound terminals, etc. have been put to practical use.

A digital telephone terminal is equipped with a CPU and a memory, and is configured to carry out protocol control adapted to a user / network interface defined in ISDN, and a PCM is used for a user information transfer channel called B channel. 6 encoded audio data
It transmits at 4 Kbps. Some of such digital telephone terminals are equipped with a terminal adapter, and are configured to perform either voice or data communication via the terminal adapter according to the operation of the changeover switch. In addition, with this terminal adapter,
IS the communication interface specified on the external terminal side
This is converted into a DN compatible interface. That is, the signal level conversion and the transmission rate conversion are performed. On the other hand, the composite terminal is configured to have a so-called personal computer communication function in addition to the communication function of the digital telephone terminal so that both the voice call and the data communication described above can be performed at the same time. That is, in the compound terminal, for example, it is possible to perform an advanced multimedia service that combines voice and image / text, such as transmitting / receiving an e-mail while transmitting a call using voice data and transmitting screen information to a communication partner. Has become.

[0004]

By the way, in the above-mentioned compound terminal, the voice and the image / text are multiplexed, and the multiplexed data is transmitted according to a predetermined frame structure. Therefore, in the compound terminal,
Since sophisticated communication control is required, the device configuration becomes complicated, resulting in a high-priced product. On the other hand, the digital telephone terminal has a simpler structure and a lower price than the composite terminal, but cannot simultaneously perform both voice data communication and data communication.

Therefore, in the case of realizing a simple multimedia service for performing well-known personal computer communication and voice communication at the same time, use of the above-mentioned composite terminal causes waste because it has an excessive communication function. On the other hand, there has been a problem that digital telephone terminals cannot provide such simple multimedia services.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide a telephone terminal device capable of supporting a simple multimedia service.

[0007]

According to the present invention, in a telephone terminal device that multiplexes serial data supplied from an external terminal and voice and sends the voice to a digital transmission line, the voice is converted into a voice signal, and The communication performed between the encoding means for generating voice data obtained by quantizing the voice signal and the external terminal is controlled according to the first protocol, and the communication data received based on the first protocol is controlled. Protocol conversion means for outputting in accordance with a second protocol, and multiplexing means for multiplexing the voice data and the communication data with bit lengths different from each other and outputting the multiplexed data as multiplexed data to the digital transmission path at octet timing. It is characterized by having.

[0008]

According to the above construction, the encoding means generates the voice data, and the protocol converting means controls the communication with the terminal in accordance with the first protocol.
The communication data received based on the second protocol is output according to the second protocol. Then, the multiplexing means multiplexes the voice data and the communication data with mutually different bit lengths, and outputs this as multiplexed data to the preceding digital transmission line at each octet timing. As a result, voice data and communication data can be simultaneously transmitted to one digital transmission line at different transmission speeds.
A simple multimedia service that performs well-known personal computer communication and voice call at the same time is realized.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of an embodiment according to the present invention. In the figure, reference numeral 20 is a telephone terminal device, and 30 is a well-known personal computer (hereinafter referred to as a personal computer) connected to the telephone terminal device 20 via a serial data transmission line (for example, RS232C). 40 is a digital communication network ISDN
It is an external terminal device connected to the telephone terminal device 20 via (Integrated Services Digital Network), and is a communication partner of the telephone terminal device 20. The telephone terminal device 20 uses a digital transmission line called "INS64" in ISDN. In the transmission line, a B channel for user information transfer having a transmission rate of 64 Kbps and a transmission rate of 16 Kbps. A control D channel is defined.

Next, the configurations of the voice communication unit, the data communication unit, and the demultiplexing unit which form the telephone terminal device 20 will be described.

Structure of voice call unit In the figure, reference numeral 1 is a handset including a microphone, a speaker and the like. Reference numeral 2 is an encoding / decoding circuit, which converts an audio signal supplied from the handset 1 to 8 KHz.
Sampling at A / D conversion is performed and PC
Outputs M-coded 8-bit long audio data. Further, the encoding / decoding circuit 2 includes a multiplexing / demultiplexing circuit 10
The voice data supplied from (to be described later) is D / A converted, and the voice signal decoded by this is converted to the handset 1
Output to.

The configuration 3 of the data communication unit is a CPU that controls the components 4 to 8 of the data communication unit. Reference numeral 4 is a ROM in which various control programs used in the CPU 3 are stored. Reference numeral 5 is a RAM in which various registers, flags, or transmission / reception data are temporarily stored. The transmission / reception data is data transmitted / received between the personal computer 30 and the external terminal device via the telephone terminal device 20, and the transmission / reception data is a RAM described later.
5, a transmission buffer 5a provided in a predetermined storage area
And the reception buffer 5b (not shown).

Reference numerals 6 to 8 denote serial data communication control circuits (hereinafter referred to as SCs) for controlling communication by a predetermined protocol.
(Abbreviated as C). First, the SCC 6 controls communication with the personal computer 30 under the control of the CPU by a well-known start-stop synchronization method (no procedure). That is, this SCC6
Controls serial data communication between the driver / receiver 9 and the port 30a (personal computer 30) connected by a serial transmission line such as RS232C. The driver / receiver 9 exchanges data with the signal standard of RS232C. Communication data transmitted and received between the SCC 6 and the personal computer 30 via the driver / receiver 9 is once stored in the transmission / reception buffers 5a and 5b described above.

Next, the SCC 7 is under the control of the CPU,
Communication data transmitted / received to / from the external terminal device 40 via a demultiplexing unit described later is converted into HDLC (High-level Data).
Link Control) Control based on the procedure. This HDLC procedure realizes transparent transmission and CR
The data is checked by C to ensure highly reliable data transfer. The SCC 7 uses the HDLC for transmitting the transmission data read by the CPU 3 from the transmission buffer 5a.
Based on the procedure, while outputting to the demultiplexing unit, the received data is transferred to the receiving buffer 5b.

Next, the SCC 8 controls the D channel link access procedure defined in "Layer 2" of ISDN. For example, call setup for connecting a line to a communication partner and communication in a network interface. Detects and recovers from failures. As described above, the data communication unit is configured to convert the communication procedure of the start-stop synchronization method (non-procedure) generally adopted in personal computer communication into the HDLC procedure and transmit / receive the communication data according to the HDLC procedure. ing.

Configuration of Demultiplexing Unit This demultiplexing unit includes a demultiplexing / demultiplexing circuit 10 and a driver / demultiplexing circuit 10.
It is composed of a receiver 11. Multiplexing / demultiplexing circuit 10
Outputs the above-mentioned voice data and communication data to the B channel as serial 8-bit multiplexed data. The demultiplexing / demultiplexing circuit 10 generates 8-bit width data at every octet timing (8 KHz). At this time, for example, the upper 7 bits of the 8 bits are assigned to the voice data, and the remaining 1 LSB is assigned to the communication data to be multiplexed. As a result, the B channel can be regarded as two transmission lines having different transmission rates.
That is, the voice data to which the higher 7 bits are allocated at each octet timing is transmitted at the transmission rate of 56 Kbps, while the communication data to which the 1 bit of LSB is assigned is transmitted at the transmission rate of 8 Kbps. To do.

Of the audio data quantized with 8 bits,
When the LSB 1 bit is removed, the effect on the actual voice call can be almost ignored. It is possible to remove the lower 2 bits of this voice data in consideration of the allowable call quality. That is, it is possible to multiplex the upper 6 bits of the audio data and the communication data assigned to the remaining lower 2 bits, and in this case, the audio data is transmitted at 48 Kbps and the communication data is transmitted at 16 Kbps. Will be done.

Multiplexing / demultiplexing circuit 1 for performing such multiplexing
0 separates the multiplexed data supplied from the communication partner via the B channel into voice data and communication data and outputs the data. The separated voice data is supplied to the encoding / decoding circuit 2 described above, while the communication data is supplied to the SCC 7. The driver / receiver 11 converts the multiplexed data into a signal format compatible with the ISDN standard and outputs it.

Next, the operation of the telephone terminal device 20 having the above configuration will be described. In the explanation of this operation, the external terminal device 40, which is the other party of the communication, performs the above-mentioned SC.
It is assumed that the call has already been set up by C8. In the state where the line connection with the external terminal device 40 is completed, first, when communication data is supplied from the personal computer 30 side to the telephone terminal device 20 by the start-stop synchronization method (no procedure), the CPU
3 sequentially writes the communication data supplied via the SCC 6 into the transmission buffer 5a. And the buffer 5
When a is in the "buffer full" state, the CPU 3 requests the SCC 7 to send out the communication data stored in the transmission buffer 5a. As a result, the SCC 7 uses the HDLC procedure to multiplex / demultiplex the communication data.
Output to 0.

On the other hand, the voice call unit is, as described above, 8
Multiplexing / demultiplexing circuit 10 for audio data quantized into bits
Supply to. The circuit 10 supplied with both the voice data and the communication data multiplexes the upper 7 bits of the voice data and the communication data of 1 bit for each octet timing, and transmits the multiplexed data via the driver / receiver 11. Transmitted to the B channel. As a result, the audio data from which the LSB 1 bit has been removed is sent out at a transmission rate of 56 Kbps, while the communication data is sent out at a transmission rate of 8 Kbps.

The multiplexed data is transmitted to the external terminal device 40 via the ISDN, and a simple multimedia service for simultaneously transmitting voice and data is realized. Next, when the same multiplexed data is transmitted from the external terminal device 40 to the telephone terminal device 20 side, the multiplexing / demultiplexing circuit 10 separates the multiplexed data into voice data and communication data. Here, the voice data is supplied to the voice call unit to be decoded, and is output as a voice signal from the speaker of the handset 1. On the other hand, the communication data is sequentially written in the reception buffer 5b via the SCC 7. Next, the communication data written in the reception buffer 5b is stored in the CPU 3 when the "buffer full" state is reached.
Is read out and supplied to the SCC 6. SCC6
Sequentially serially transfers the supplied communication data in accordance with the protocol of the personal computer 30.

As described above, according to the above-described embodiment, the serial data communication is performed between the personal computer 30 and the telephone terminal device 20 according to the protocol called "procedure" as in the conventional personal computer communication. Between the device 20 and the external terminal device 40, this "non-procedure" is changed to "HDL".
The C "procedure is converted to ensure transparent and error-free communication, and data transmission is performed according to the ISDN compatible standard. Then, in data transmission, voice data and communication data are multiplexed so that one B channel can be regarded as two communication paths having different transmission speeds.
As a result, a simple multimedia that simultaneously transmits both is realized.

In the above embodiment, the protocol conversion is performed when the transmission buffer 5a and the reception buffer 5b are in the buffer full state, respectively.
Instead of this, for example, timer interrupt processing for protocol conversion may be performed at regular intervals. Further, in the protocol conversion, “non-procedure” is converted to “HDLC” or “HDLC” is converted to “non-procedure” according to the transmission / reception mode, but the present invention is not limited to this and may be converted to another protocol. .. The point is that the "no procedure" used in personal computer communication can be converted into a protocol that provides transparent and error-free communication.

[0024]

As described above, according to the present invention, the encoding means generates the voice data, and the protocol converting means controls the communication with the external terminal according to the first protocol. At the same time, the communication data received based on the first protocol is output according to the second protocol. Then, the multiplexing means multiplexes the voice data and the communication data with bit lengths different from each other and outputs the multiplexed data to the digital transmission line at every octet timing. As a result, since voice data and communication data are simultaneously transmitted to one digital transmission line at different transmission rates, it is possible to support a well-known simple multimedia service in which a personal computer communication and a voice call are simultaneously performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a telephone terminal device 20 according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Handset, 2 ... Encoding / decoding circuit, 3 ... CPU, 4 ... ROM, 5 ... RAM, 6-8 ... SCC, 10 ... Multiplexing / separating circuit, 20 ... Telephone terminal device, 30 ... Personal computer, 40 ... External terminal device.

Claims (1)

[Claims] 1. A telephone terminal device for multiplexing serial data supplied from an external terminal and voice and transmitting the voice to a digital transmission line, wherein the voice data is converted into a voice signal and the voice signal is quantized. Controlling the communication performed between the encoding means for generating and the external terminal according to the first protocol, and outputting the communication data received based on the first protocol according to the second protocol. A protocol converting means; and a multiplexing means for multiplexing the voice data and the communication data with bit lengths different from each other and outputting the multiplexed data as multiplexed data to the digital transmission path at each octet timing. Telephone terminal equipment.