JP2000101571A - Synchronization control method for terminal adapter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To normally perform communication in interconnection of terminal adapters between different makes by providing a buffer in the terminal adapter and adjusting a timing between control signals and data signals sent out to an ISDN line and received from the ISDN line matching the opposing terminal adapter. SOLUTION: At the time of transmitting and receiving the control signals and data signals of an ITU-T recommendation V.24 standard, synchronization between the control signals and the data signals is varied. A transmission data buffer 8 and a control signal buffer 11 respectively delay transmission data and the control signals from a V.24 DTE interface 7 corresponding to a delay from a control part 15 and then, send them out to an ISDN frame generation part 9. A reception data buffer 12 and the control signal buffer 14 respectively delay the transmission data and the control signals delivered from an ISDN frame development part 13 corresponding to the delay value from the control part 15 and then, send them out to the V.24 DTE interface 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal adapter connected to an ISDN line, and more particularly to a synchronization control method for the terminal adapter.

[0002]

2. Description of the Related Art A conventional technique will be described with reference to FIG.
The terminal adapter 2 is connected to the terminal adapter 4 which is connected to the terminal adapter 4 via the ISDN line 3 and has an ITU-
T Recommendation V. When transmitting and receiving control signals and data signals of the H.24 standard to each other, the terminal 1 connected to the terminal adapter 2
When the terminal adapter 2 returns the transmission enable control signal to the terminal 1 in response to the transmission request control signal from the terminal 1 being turned on, the transmission data signal transmitted from the terminal 1 is transmitted from the terminal adapter 4 to the terminal adapter 4 Terminal adapter 2 so that it is transmitted as a received data signal after turning on the data channel reception carrier detection control signal to terminal 5 connected to ITU-T Recommendation V.3. 1
The timing between the control signal and the data signal transmitted in a frame to the ISDN line 3 is adjusted in accordance with the 10 standards. In the reverse control, ISDN
From line 3 to ITU-T Recommendation V. The timing at which a frame received according to the H.110 standard is developed into a control signal and a data signal is matched.

Also, in response to the transmission request control signal being turned off from the terminal 1 to which the terminal adapter 2 is connected, when the terminal adapter 2 returns the transmission enable control signal to the terminal 1, the transmission request control signal is transmitted from the terminal 1 before. The terminal adapter 2 transmits the transmission data signal from the terminal adapter 4 to the terminal 5 connected to the terminal adapter 4 as a reception data signal before the data channel reception carrier detection control signal is turned off. 110
According to the standard, the timing between the control signal and the data signal transmitted in a frame to the ISDN line 3 is matched. Then, in the control in the opposite direction, the ITU-T Recommendation V. The timing at which a received frame was expanded into a control signal and a data signal according to the 110 standard was matched.

[0004]

The above prior art is based on the IT
U.T. Recommendation V. Since the relationship between the control signal and the data signal of the H.24 standard is adjusted by the unique timing between the terminal adapters connected to each other via the ISDN network, the above timing differs for each terminal adapter manufacturer. In the interconnection of terminal adapters of ITU-T Recommendation V. There is a problem that the timing between the control signal of the H.24 standard and the data signal is shifted and normal data communication cannot be performed.

[0005] The present invention relates to a timing between a control signal and a data signal transmitted to an ISDN line for each terminal adapter to be connected to each other, and to an ITU-T Recommendation V.1 from an ISDN line. ITU-T in the interconnection of terminal adapters between different manufacturers by aligning the timing between control signals and data signals received according to the H.110 standard
Recommendation V. It is intended that communication of the H.24 standard can be performed normally.

[0006]

In order to achieve the above-mentioned object, a buffer is provided in a terminal adapter so that ITU-T Recommendation V.10 can be used. Timing between control signal and data signal transmitted to ISDN line according to H.110 standard and I
ITU-T Recommendation V. This makes it possible to adjust the timing between the control signal and the data signal received according to the H.110 standard in accordance with the counter terminal adapter.

Further, the adjusted parameters are stored in the ISDN
By having a terminal adapter for each telephone number of terminal adapters interconnected via a line, terminal adapters manufactured by many other manufacturers and ITU-T Recommendations Normal data communication of 24 standards can be performed.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a system configuration diagram to which the present invention is applied.

The terminal adapter 2 is an ISDN line 3
Are interconnected with the terminal adapter 4. The terminal 1 and the terminal 2 are connected to the terminal adapter 2 and the terminal adapter 4 provided by the ITU-T Recommendation V.4. 24
Perform mutual data communication according to the standard.

FIG. 2 is a diagram showing the internal structure of the terminal adapter 2.

The ISDN interface 10 is an ISDN
The connection and disconnection control with the ISDN line 3 which is connected to the line 3 according to the control of the control unit 15 and sends frame data from the ISDN frame generation unit to the ISDN line 3 and performs ISD
Transmission / reception control for passing the frame data received from the N line 3 to the ISDN frame development unit is performed. The ISDN frame generation unit 9 converts the transmission data from the transmission buffer 8 and the control signal from the control signal buffer 11 into ITU-T Recommendation V. 11
According to the standard 0, the frame is sent to the ISDN interface 10 in an ISDN frame. ISDN frame development unit 13
Is the ISDN passed from the ISDN interface 10.
The frame is described in ITU-T Recommendation V. In accordance with the H.110 standard, the received data and control signal are expanded, and the received data is sent to the received data buffer 12 and the control signal is sent to the control signal buffer 14. The transmission data buffer 8 has The transmission data from the 24DTE interface 7 is delayed according to the delay value passed from the control unit 15 and then transmitted to the ISDN frame generation unit 9. The control signal buffer 11 controls the V.V. 24DT
The transmission data from the E interface 7 is delayed according to the delay value passed from the control unit 15 and then transmitted to the ISDN frame generation unit 9. Receive data buffer 12 is ISD
After delaying the received data passed from the N frame developing unit 13 in accordance with the delay value passed from the control unit 15, V.N. 24
Sends to DTE interface 7. The control signal buffer 14 delays the control signal passed from the ISDN frame developing unit in accordance with the delay value passed from the control unit 15, and Send to 24DTE interface 7. V. 24
The DTE interface 7 transmits transmission data and a control signal from the terminal 1 to a transmission data buffer 8 and a control signal buffer 11.
To the terminal 1 and the received data from the received data buffer 12 and the control signal from the control signal buffer 14 to the terminal 1. When connected to the ISDN line 3, the control unit 15 transmits the ITU-T Recommendation V.10 for each telephone number of the terminal adapter 4.
A delay value registered in advance is set in each buffer so that normal data communication of 24 standards can be performed.

[0013]

As described above, according to the present invention,
For interconnection with terminal adapters of different manufacturers, ITU-T recommendation V. It is possible to perform normal data communication of 24 standards.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a system configuration according to an embodiment of the present invention.

FIG. 2 is an internal configuration diagram of a terminal adapter according to an embodiment of the present invention.

[Explanation of symbols]

1, 5, terminal, 2, 4, 6 terminal adapter, 3
ISDN line, 7 ... V. 24 DTE interface, 8
... Transmission data buffer, 9 ... ISDN frame generation unit,
10: ISDN interface, 11, 14: control signal buffer, 12: received data buffer, 13: ISDN
Frame developing unit, 15 ... Control unit.

Claims (1)

[Claims] 1. A terminal device for connecting to an ISDN line (integrated digital communication network) and connecting to the ISDN line is provided by ITU-T Recommendation V.4 defined by the International Telegraph and Telephone Advisory Committee. Terminal adapters interconnected according to the ITU-T Recommendation V.24. Control signals and data signals of the ITU-T Recommendation V.24 are transmitted to the ISDN line. When transmitting and receiving according to the H.110 standard, the ITU-T
Recommendation V. 24. A method for controlling the synchronization of a terminal adapter, wherein the synchronization between a control signal and a data signal conforming to the H.24 standard is varied to guarantee data in a terminal adapter having different synchronization control and interconnection via the ISDN line.