JP3293559B2 - Line controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line controller to which a plurality of digital transmission terminals are connected, and more particularly, to a line controller for connecting and disconnecting the lines of these digital transmission terminals.

[0002]

2. Description of the Related Art Conventionally, as a concept of communication, a form in which a certain point is connected to another point and information is mutually transmitted and received is generally used. However, in the information communication society in recent years, it is necessary to connect one point to a plurality of points and transmit and receive information to and from each other. As such point-to-multipoint communication, for example, a remote monitoring system in which a central monitoring station collects monitoring statuses of monitoring devices at a plurality of points, or a remote education in which a lecture given in a classroom is directly delivered to a plurality of points And other broadcasting systems. The central office and the plurality of points in these communication systems are, for example, integrated service digital networks (In
integrated Services Digital Network: ISDN
Abbreviated. ) Each is connected by a public line such as a line.

[0003] Taking the above-mentioned remote monitoring system as an example, a plurality of monitoring points, each of which is installed at a point isolated at a long distance, have a one-to-one correspondence with a monitoring station as a central station.
They are connected via SDN lines. The monitoring station collects information such as video and audio from a plurality of monitoring points via an ISDN line, and constructs a system in the monitoring station so that necessary information can be easily obtained according to the monitoring purpose. There is a line control device that selects and switches a plurality of lines to which monitoring information from such a plurality of monitoring points is transmitted.

FIG. 10 shows an outline of the configuration of a conventionally proposed line control device. This line control device transmits an image signal 10 to a first ISDN line 11 and a second
A line can be selected and switched to transmit to or receive from any one of the SDN line 12 and the high-speed digital leased line 13. The line control device that enables such line selection and switching transmits a switching unit 14 for switching the line on which the image signal 10 is transmitted, and a switching signal 15 for selecting and switching the line to the switching unit 14. And a switching control unit 16. Further, the first IS
A first ISDN line terminating unit 17 for transmitting / receiving a line connection signal to / from a line termination of the DN line 11 and a second ISDN line termination unit 17 for transmitting / receiving a line connection signal to / from the line termination of the second ISDN line 12. 2 ISDN line terminating unit 18 and a high-speed digital line terminating unit 19 for transmitting and receiving the line termination of the high-speed digital leased line 13 and the line connection signal to / from the other party
And

The switching control unit 16 sends a switching signal 15 to the switching unit 14 in response to an operator pressing a button (not shown) corresponding to the line to be selected as the transmission line, and switches the line terminating units 17 to 19. Sends a transmission instruction signal of the line connection signal of the partner station to the other station. The line termination unit of the selected line sends a line connection signal to the partner station to perform a predetermined line connection process. The image signal 10 transmitted on the line selected in this way is usually coded immediately before that, and then transmitted to the line from each line terminal selectively connected by the switching unit 14. In addition, the image signal 10 received from the line termination unit via the selected line via the switching unit 14 is thereafter compounded and used in, for example, a monitoring television system.

The technology related to such a line control device is as follows.
For example, it is disclosed in Japanese Patent Application Laid-Open No. 5-316247, "Image Transmission Coding Apparatus".

[0007]

In such a conventional line control device, each monitoring terminal for collecting monitoring information in the above-described remote monitoring system must be connected by an ISDN line. In the above description, an ISDN line is taken as an example, but one line is required for each connection monitoring terminal, not limited to the ISDN line. In other words, the number of lines to be used increases each time the number of monitoring points increases, so that there is a problem that the operation cost of the system also increases.

In order to obtain monitoring information intended for monitoring at the monitoring station in this way, transmission terminals are installed in the monitoring station in correspondence with each monitoring point, and are constantly monitored by being connected to each monitoring point on a one-to-one basis. In order to reduce the total cost of the system, there is a case where only one transmission terminal is installed at the monitoring station and the line is repeatedly connected to and disconnected from each monitoring point at a fixed time interval to perform periodic monitoring. Was. However, connection to each monitoring point by a public line such as an ISDN line is required. In particular, when one transmission terminal is installed in the monitoring station, while communicating with the monitoring station from one monitoring point, another monitoring point obtains information intended for monitoring and transmits it to the monitoring station. However, the monitoring station may not be able to transmit data because it is busy. Even if the monitoring information is not lost by the additional service of the line carrier, the monitoring station cannot obtain the monitoring information in real time. In order to transmit the information to the monitoring station in real time, it is necessary to temporarily disconnect the connection with the transmission terminal that is in a call and then connect the transmission terminal to the transmission terminal that has attempted to transmit the monitoring information again. However, there has been a problem that a delay time is generated due to a conventional connection and disconnection sequence of the ISDN line, and thus a monitoring station cannot obtain monitoring target information in real time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a line control apparatus for quickly selecting and switching a line for collecting information transmitted via the line in real time.

[0010]

According to the first aspect of the present invention, there is provided a line connection request receiving means for receiving a line connection request transmitted from a first transmission terminal to be connected and a line number for which the connection is requested. And (b) indicating whether to permit a line connection request of the first transmission terminal in response to a line connection request from another transmission terminal other than the first transmission terminal among the plurality of connected transmission terminals. Line connection permission receiving means for receiving a line connection permission; and (c) permitting a line connection request from all transmission terminals except the first transmission terminal with reference to the line connection permission received by the line connection permission reception means. Line connection permission determination means for determining whether or not a line connection permission for connection is received; (d) line connection detection means for detecting whether a predetermined line to be connected is being connected; By connection permission judgment means It is determined that the line connection permission was received from all of the transmission terminal other than the first transmission terminal, and the first transmission terminal when the predetermined line mentioned above is determined to be in connection with the line connection detecting means the transmission signal of the transmission signal sending means for sending to the predetermined line,
(F) is determined to be received line connection permission by line connection permission determination unit from all transmission terminals except the first transmission terminal, and where the above by the line connection detecting means
When it is determined that the fixed line is not being connected, a line connection for setting a line for transmitting a transmission signal from the first transmission terminal in accordance with the line number received by the line connection request receiving means. The line control device is provided with setting means.

That is, according to the first aspect of the present invention, a line connection request and a line number for which the connection is requested are received from a first transmission terminal among a plurality of transmission terminals to be connected. Further, in response to the line connection request of the first transmission terminal, a line connection permission is received from another transmission terminal indicating whether or not this line connection request is permitted. The line connection permission determining means refers to the line connection permission received in this manner, and requests the line connection request of the first transmission terminal from all the other transmission terminals except the first transmission terminal which made the line connection request. When a line connection permission for permitting is received, it is determined that the line connection request is permitted. When the line connection of the first transmission terminal is determined to be permitted by the line connection permission determination means, and a predetermined line is being connected, a transmission signal from the first transmission terminal is transmitted to the predetermined line . I do. On the other hand, the line connection of the first transmission terminal is determined to allow the line connection permission determination means, and where the said
When the fixed line is not connected, the connection of the line for transmitting the transmission signal from the first transmission terminal is set in accordance with the line number transmitted by the first transmission terminal.

According to the second aspect of the present invention, (a) a line disconnection request receiving means for receiving a line disconnection request sent from the first transmission terminal to be connected; Line disconnection permission receiving means for receiving a line disconnection permission indicating whether to permit a line disconnection request of the first transmission terminal in response to a line disconnection request from all transmission terminals except the first transmission terminal. And (c) referencing the line disconnection permission received by the line disconnection permission receiving means to determine whether a line disconnection permission for permitting a line disconnection request has been received from all transmission terminals except the first transmission terminal. A line disconnection permission determining means for determining, and (d) a line for disconnecting the connected line when the line disconnection permission determining means determines that the line disconnection permission has been received from all the transmission terminals except the first transmission terminal. Off It is made to and means the line control device.

That is, according to the present invention, the line is disconnected from the first transmission terminal among the plurality of transmission terminals to be connected.
Receive the request . Further, in response to the line disconnection request of the first transmission terminal, a line disconnection permission indicating whether or not to permit the line disconnection request from all other transmission terminals is received.
The line disconnection permission determining means refers to the line disconnection permission received in this manner, and requests the line disconnection request of the first transmission terminal from all the other transmission terminals except the first transmission terminal that made the line disconnection request. When a line disconnection permission for permitting the line disconnection is received, it is determined that the line disconnection request is permitted. When the line disconnection permission determination unit determines that the line disconnection of the first transmission terminal is permitted, the line being connected is disconnected.

According to a third aspect of the present invention, in the line control device according to the first aspect, the line connection request receiving means is a line connection request sent from the first transmission terminal to be connected and a line for requesting the line connection. Upon receiving the number, the transmission signal sending means determines that the line connection permission has been received from all the transmission terminals except the first transmission terminal by the line connection permission determination means, and the line connection detection means determines that the line is being connected. When it is determined that there is, the transmission signal from the first transmission terminal is transmitted from the plurality of connected lines to the line corresponding to the line number received by the line connection request receiving unit, and the line connection setting unit transmits the line connection permission signal. The determination means determines that the line connection permission has been received from all the transmission terminals except the first transmission terminal, and the line connection detection means determines that the line is being connected. It is characterized by performing the channel connection setting corresponding to the line number received by the line connection request receiving means from a plurality of lines when the yarn is determined.

That is, according to the third aspect of the present invention, a plurality of lines are connected, and a line number for requesting a line connection received simultaneously with a line connection request from the first transmission terminal by the line connection request receiving means. The transmission or connection setting to the line corresponding to.

According to a fourth aspect of the present invention, in the line controller according to the second aspect, the line disconnection request receiving means transmits the line disconnection request sent from the first transmission terminal to be connected and the line for requesting the line disconnection. When the number is received and the transmission signal transmission means determines that the line disconnect permission has been received from all the transmission terminals except the first transmission terminal by the line disconnect permission determination means, the transmission signal transmission means receives from the plurality of lines by the line disconnect request reception means. The connected line corresponding to the specified line number is disconnected.

That is, in the invention according to claim 4, a plurality of lines are connected, and a line number for requesting a line disconnection received simultaneously with a line disconnection request from the first transmission terminal by the line disconnection request receiving means. The line corresponding to is disconnected.

According to a fifth aspect of the present invention, in the line control device according to the first or third aspect, a line connection request of an arbitrary transmission terminal among a plurality of transmission terminals to be connected and a line number for which the connection is requested are specified. A line connection request inputting means for inputting from outside, the transmission signal transmitting means is provided with a line connection detecting means when a line connection request is inputted from outside by the line connection request inputting means irrespective of the judgment result by the line connection permission judging means; When it is determined that the line is being connected, the transmission signal from the transmission terminal that has requested the line connection by the line connection request input means is transmitted to the line,
When a line connection request is input from the outside by the line connection request input unit, the line connection setting unit determines whether the line is not being connected by the line connection detection unit regardless of the result of the determination by the line connection permission determination unit. A line connection corresponding to a line number for transmitting a transmission signal from a transmission terminal that has requested a line connection by a line connection request input unit is set.

That is, according to the fifth aspect of the present invention, there is provided a line connection request input means for inputting a line connection request of an arbitrary transmission terminal among a plurality of transmission terminals connected from the outside and a line number for which the connection is requested. ing. The line connection request of an arbitrary transmission terminal input by the line connection request input means performs transmission to the line or connection setting of the line corresponding to the line number irrespective of permission of the line connection from another transmission terminal. Like that.

According to a sixth aspect of the present invention, in the line controller according to the second or fourth aspect, a line disconnection request for externally inputting a line disconnection request of an arbitrary transmission terminal among a plurality of connected transmission terminals. Input means, and when a line disconnection request is input from the outside by the line disconnection request input means, the line disconnection request means irrespective of the judgment result by the line disconnection permission judging means. It is characterized by cutting.

That is, the invention according to claim 6 is provided with a line disconnection request input means for inputting a line disconnection request of an arbitrary transmission terminal among a plurality of transmission terminals connected from the outside and a line number for which the disconnection request is made. ing. The line disconnection request of an arbitrary transmission terminal input by the line disconnection request input means disconnects the line corresponding to the line number irrespective of permission of line disconnection from another transmission terminal.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments.

First Embodiment

FIG. 1 shows an outline of a configuration of a line control device according to a first embodiment of the present invention. The line controller 20 includes N (N is plural) first digital transmission terminals 21 ₁ , second digital transmission terminals 21 ₂ ,
..., digital transmission terminal 21 _N of the N are connected via the interface connection line 22 ₁ through 22 _N. These interfaces connecting lines 22 ₁ through 22 _N, as the interface signals between the line control unit 20, respectively, and transmitting and receiving digital signals as the communication data,
A line connection request signal as a line connection request, a line connection permission signal as a connection permission corresponding to the line connection request, a line disconnection request signal as a line disconnection request,
A line disconnection permission signal as disconnection permission corresponding to the line disconnection request, a dial signal for connecting an unconnected line, and another terminal line connection indicating that a terminal other than the own terminal has requested a line connection. There is a request signal and another terminal line disconnection request signal indicating that a terminal other than the terminal itself has requested a line disconnection. With such an interface signal, the first to Nth digital transmission terminals 21 _{1 to} 21 _N
After the transmission / reception signal is selected and switched by the line control device 20, the signal is transmitted / received to / from the other party via the ISDN line 23.

The line control device 20 is connected to each of the transmission terminals 21 ₁ to 21 ₁ .
An input / output interface 24 for converting the level of an interface signal with the 21 _N ;
4, a transmission signal switching unit 25 for selecting and switching transmission signals from each of the transmission terminals 21 _{1 to} 21 _N , and transmitting the transmission signals switched by the transmission signal switching unit 25 to the ISD
And a ISDN line interface unit 26 for sending the received signal through the input-output interface unit 24 to the transmission terminal 21 ₁ through 21 _N from the ISDN line 23 sends out to the N line 23. Further, the device control unit 27
Performs line selection and switching control on the transmission signal switching unit 25 based on the interface signals from the transmission terminals 21 _{1 to} 21 _N input via the input / output interface unit 24. An operation unit 28 for forcibly connecting and disconnecting the line from the outside is connected to the device control unit 27.

The input / output interface unit 24 receives, for example, an RS (Recommended Stan) from each of the transmission terminals 21 _{1 to} 21 _N.
dard) A transmission signal having a signal level of an interface connection line such as -449 is converted into a device level, and a reception signal received via the ISDN line interface unit 26 is converted from the device level to a signal level of the interface connection line. converted and sent to each of the transmission terminals 21 ₁ through 21 _N. The transmission digital signals 29 _{1 to} 29 _N from the transmission terminals 21 _{1 to} 21 _N converted into the device level by the input / output interface unit 24 are input to the transmission signal switching unit 25. The transmission signal switching unit 25 is an N: 1 switch (N-input / 1-output selector), and the first to N-th digital transmission terminals 21 _{1 according} to the transmission selection signal 30 and the operation permission signal 31 input from the device control unit 27. to 21 any one of _N is selected and inputted to the ISDN line interface unit 26 as a transmission switching digital signal 32.

FIG. 2 shows an outline of the configuration of such a transmission signal switching unit 25. The device signal switching unit 25 includes an N input 1 selector circuit 33 and a selection output switching unit 34. The N input 1 selector circuit 33 receives N transmission digital signals 2 according to the transmission selection signal 30.
One transmission signal can be selected from 9 _{1 to} 29 _N. The selection output switching unit 34 can switch on / off the output of the transmission selection signal 30 by the operation permission signal 31. By holding the transmission selection signal 30, when the output is turned off, the held previous value is output as it is, so that the configuration of the subsequent circuit can be simplified.

Returning to FIG. 1, the description will be continued.

In the ISDN line interface unit 26,
The transmission switching digital signal 32 is transmitted to the International Telecommunication Union (IT) telecommunication standardization section (International Telecommunication Union), which is the electrical interface condition of the ISDN line 23.
n-Telecommunication Sector (ITU-T) Recommendation I.T.
430 based on the transmission frame structure
Converted to the transmission line signal level of the DN line and converted to the ISDN line 2
3 On the other hand, the signal received via the ISDN line 23 is
U.T. Recommendation I. The transmission frame conforming to 430 is converted into an in-apparatus frame, and after being converted into an in-apparatus level, is input as a received digital signal 35 to each of the transmission terminals 21 _{1 to} 21 _N via the input / output interface unit 24. The reception digital signal 35 is transmitted to the input / output interface unit 24.
In converted to the signal level of the interface connection line, is delivered to all the digital transmission terminal 21 ₁ through 21 _N. Each transmission terminals 21 ₁ through 21 _N, and obtained by separating the video and audio data from the received digital signal framed preassigned to the radio terminal, the video data in the transmission terminal 21 ₁ through 21 _N image Output and audio data are output as audio.

Each transmission terminal uses the ISD of the line controller 20.
A status display signal (not shown) from the N-line interface unit 26 can be monitored.
Any transmission terminal can recognize whether the N line 23 is under line connection or not connected. Therefore, when information to be transmitted to the transmission terminal is generated and should be transmitted, or at the start of reception, if the same line as the already connected line is used while the line is already connected, the transmission terminal is connected via the interface connection line. And output a line connection request. This line connection request is input to the device control unit 27 as a line connection request signal 36 via the input / output interface unit 24. This line connection request signal 3
6 is transmitted as the other terminal line connection request signal 37 to all transmission terminals other than the transmission terminal that has transmitted this.
For example, if ₂ second digital transmission terminal 21 that sends a line connection request signal, the digital transmission terminal 21 of the _first and third to N, 21 ₃ through 21 in _N other terminal line connection request signal 37 Will be notified. When each transmission terminal receives the other terminal line connection request via the interface connection line, it transmits a line connection permission signal according to the state of each transmission terminal. For example, when the transmission terminal that has received the other terminal line connection request has information to be transmitted, the line connection is not permitted, and the transmission is continued or the line connection request is made. , Line connection permission can be made. The line connection permission signal is input to the device control unit 27 via the input / output interface unit 24 as a line connection permission signal 38.

On the other hand, when information to be transmitted to the transmission terminal occurs and transmission is to be performed, or at the start of reception, when a line different from the already connected line is used when the line is already connected,
This transmission terminal outputs a line disconnection request via the interface connection line. This line disconnection request is input to the device control unit 27 via the input / output interface unit 24 as a line disconnection request signal 39. This line disconnection request signal 39
Is transmitted as the other-terminal line disconnection request signal 40 to all transmission terminals other than the transmission terminal that has transmitted this. For example, if ₂ second digital transmission terminal 21 that sends a line disconnection request signal, the digital transmission terminal 21 of the _first and third to N, 21 ₃ through 21 in _N other terminal line disconnection request signal 40 Will be notified. When each transmission terminal receives the other terminal line disconnection request via the interface connection line, it transmits a line disconnection permission signal according to the state of each transmission terminal. For example, when the transmission terminal that has received the other terminal line connection request has information to be transmitted, the line disconnection permission is not permitted, and otherwise, the line disconnection permission is permitted. . The line disconnection permission signal is transmitted via the input / output interface unit 24 to the line disconnection permission signal 4.
1 is input to the device control unit 27.

Further, when information to be transmitted is generated from the transmission terminal and the line is not connected at that time, the transmission terminal receives the line connection request via the interface connection line and the line number of the destination. Output dial signal. The line connection request and the dial signal are input to the device control unit 27 via the input / output interface unit 24 as a line connection request signal 36 and a dial signal 42, respectively.

The device control unit 27 receives a line connection request signal 36 sent from an arbitrary digital transmission terminal and a line connection permission signal 38 from a digital transmission terminal other than the transmission terminal that sent the line connection request. To detect a port connection request from a digital transmission terminal connected to which port, and a transmission selection signal 30
Generate Also, referring to the line connection permission signal 38 from a transmission terminal other than the transmission terminal that has transmitted the line connection request, if all of these are connection permitted, the operation permission signal is regarded as connection permission of the transmission terminal that transmitted the line connection request. 31 is generated to be enabled. These transmission selection signals 3
0 and the operation permission signal 31 are output to the transmission signal switching unit 25.

Further, the device control unit 27 can monitor a status display signal (not shown) from the ISDN line interface unit 26 like each transmission terminal, and determines whether the line is connected or not connected. It can recognize whether it is connected. Therefore, when a line connection request is input while it is recognized that the line is not connected, the reception of a dial signal 42, which is the line connection destination, is awaited. Then, as described above, when it is determined from another transmission terminal that the line connection is permitted by the line connection permission signal 38, the transmission selection signal 30 and the operation permission signal 31 are output to the transmission signal switching unit 25, and the transmission terminal In addition to selecting and switching, ISDN line interface unit 2
Then, a line connection control signal 43 is sent to 6 to perform line connection processing.

Similarly, the apparatus control unit 27 receives a line disconnection request signal 39 from a certain transmission terminal, and receives a line disconnection permission signal 41 from all transmission terminals other than the terminal that requested the line disconnection.
Is input, it is determined that the line disconnection is permitted, and IS
A line disconnection control signal 44 is sent to the DN line interface unit 26 to perform a line disconnection process.

In the ISDN line interface unit 26,
It controls the layers 1 to 3 of the D channel protocol. The layer 1 mainly converts the signal into a signal that satisfies the electrical and physical conditions of the ISDN line 23, the layer 2 mainly performs data transfer control for dealing with transmission errors and improving reliability, and the layer 3 mainly performs data transfer control. A predetermined call process for an ISDN line such as call setup and call release can be performed. Upon receiving the line connection control signal 43 from the device control unit 27, a new line is connected by a predetermined line connection control for transmitting a call setting message to which the line number of the other party is added as a Layer 3 message of Layer 3. When the line disconnection control signal 44 is received from the device control unit 27, the line is disconnected by a predetermined line disconnection control for transmitting a call release message to which a call number to be disconnected is added.

The operation section 28 can also issue an instruction regarding the line connection and the line disconnection described above. That is, when a desired transmission terminal is to be connected to an already connected line, a line connection external request signal 45 is input from the outside to the device control unit 27. The apparatus control unit 27, the line connection external request signal 45 from the outside, with priority over all line connection request signal 36 from the transmission terminal 21 ₁ through 21 _N, the line connection enable signal from other transmission terminals The transmission selection signal 30 and the operation permission signal 31 are transmitted by the transmission signal switching unit 25 so that the transmission digital signals 29 _{1 to} 29 _N are forcibly switched regardless of the transmission digital signal 29.
Output to When the line is not connected, a line connection external request signal 45 of an arbitrary transmission terminal is input, and an external input dial signal 46, which is the number of the line connection destination of the other party, is input. _A predetermined line connection process is performed by forcibly sending a line connection control signal 43 to the ISDN line interface unit 26 regardless of the line connection request signal 36 and the line connection permission signal 38 from _{1 to} 21 _N. You can do it. Further, when an arbitrary transmission terminal wants to disconnect the line even while the line is connected, a line disconnection external request signal 47 is input to the device control unit 27 from outside. Then
Regardless line disconnection request signal 39 and line disconnection permission signal 41 of the transmission terminal 21 ₁ through 21 _N are connected, forcibly given by sending a line disconnection control signal 44 with respect to the ISDN line interface unit 26 Line disconnection processing can be performed.

Next, a description will be given of the device control unit 27 which enables such line connection control and line disconnection control.

FIG. 3 shows an outline of the configuration of the device control unit 27.
I forgot. The device control unit 27 includes an input / output interface.
1st to Nth digital transmission terminals via the base unit 24
21 ₁~ 21_NEach to store the interface signal between
Seed registers and the I / Os stored in these registers.
Line connection control and
A central processing unit 50 for performing line disconnection control;
And switching of the transmission signal switching unit 25 according to the processing result of
Selection signal 30 for performing switching control and operation permission
A line connection permission signal of each transmission terminal for generating the signal 31
And a terminal number that identifies
A communication selection register 51. I / O interface
The first to Nth digital transmission terminals 2 via the
1₁~ 21_NVarious to store the interface signal between
As a group of registers, the first to Nth digital transmission terminals 2
1₁~ 21_NLine connection request signal 36 corresponding to each₁
~ 36_N, A connection request register unit 52 for storing
Nth digital transmission terminal 21₁~ 21_NFor each
Line connection permission signal 38₁~ 38_NPermission to store
A register unit 53 and first to Nth digital transmission terminals 2
1₁~ 21_NLine disconnection request signal 39 corresponding to each₁
~ 39_NAnd a disconnection request register unit 54 for storing
Nth digital transmission terminal 21₁~ 21_NFor each
Line disconnection permission signal 41₁~ 41_NStore disconnect permission
There is a register section 55.

Each of the register groups 51 to 55 is connected to the central processing unit 50 via an N-bit internal bus 56. The connection request register section 52, the connection permission register section 53, the disconnection request register section 54, and the disconnection permission register section 55 are read-only registers for the central processing section 50, and the transmission selection register section 51 includes the central processing section 50
Is a write-only register. Further, the central processing unit 50 receives a line connection external request signal 45, an external input dial signal 46, and a line disconnection external request signal 47 from the external operation unit 28. Furthermore, a dial signal 42 ₁ for inputting a dial number which is a line connection number of a destination for line connection when a line is not connected, corresponding to each of the _first to Nth digital transmission terminals 21 _{1 to} 21 _N.
~42 _N is adapted to be input. The central processing unit 50 is connected to the ISDN line interface unit 26 via an N-bit internal bus 56, sends out the line connection control signal 43 and the line disconnection control signal 44 in a predetermined format, and outputs the ISDN line interface unit. 26 can be referred to.

The central processing unit 50 to which such an interface signal is input is provided with a central processing unit (Centra not shown).
l Processing Unit: Hereinafter abbreviated as CPU. ), And an external storage device such as a magnetic disk or a read only memory (Read Only Memory) provided separately from the external storage device.
Various processes such as the line connection control and the line disconnection control described above can be executed based on a program stored in a predetermined storage device such as a ry: ROM. FIG.
An outline of these processing procedures will be described with reference to FIG.

FIGS. 4 and 5 show the outline of the line connection processing procedure performed by the CPU (not shown) of the central processing unit 50. First, it is determined whether or not the line connection external request signal 45 has been input from the external operation unit 28 (step S60). When it is determined that the line connection external request signal 45 has not been input from the external operation unit 28 (step S60: N), the connection request register unit 52 is read out via the N-bit internal bus 56 (step S60). Step S61), it is detected whether there is a line connection request from any of the _first to Nth digital transmission terminals 21 _{1 to} 21 _N to be connected (step S62). here,
When it is detected that there is one less line connection request transmission terminals 21 ₁ through 21 _N: (step S62 Y) reads the connection permission register 53 via the N-bit internal bus 56 (step S63 ). At each transmission terminal,
All transmission terminals other than the transmission terminal that sent the previous line connection request are notified as the other terminal line connection request signal 37, and for example, each transmission terminal receiving the other terminal line connection request has information to be transmitted. If so, the line connection is not permitted. Otherwise, the line connection is permitted. In this way, a line connection permission signal indicating permission or non-permission of the line connection from the transmission terminal that has requested the line connection is input to the connection permission register unit 52 from each transmission terminal.

On the other hand, when there is no line connection request from any of the transmission terminals 21 _{1 to} 21 _{N in} step S62 (step S62).
62: the N) after the predetermined time T ₁ elapses are predetermined (step S64: monitoring the input of the line connection external request signal 45 Y) again from the outside of the operation portion 28 of the step S60. In this way, unless the line connected to an external request from outside, the connection request register unit 5 at a predetermined T ₁ cycle
2, the line connection request signal 36 is monitored.

In step S63, the connection permission register 53
Is read, the read line connection permission signal 38
_It is detected whether or not the terminal requesting the line connection has a line connection permission based on _{1 to} 38 _N (step S6).
5). Here when all line connection permission from the transmission terminal other than transmission terminal which outputs a line connection request is not input: (step S65 N), the predetermined that predetermined time T ₂ after a lapse (Step S66 : Y), the input of the line connection external request signal 45 from the external operation unit 28 in step S60 is monitored again. In this way, unless the line connected to an external request from an external line connection request if there has, the line connection permitting signal 38 ₁ to 38 DEG _N with reference to the connection permission register unit 53 at a predetermined T ₂ cycles Perform monitoring.

If the line connection permission has been input from all the transmission terminals other than the transmission terminal that has output the line connection request in step S65 (step S65: Y), the ISDN line interface is connected via the N-bit internal bus 56. Referring to the line status display signal of the unit 26 (step S6).
7) It is detected whether or not the ISDN line 23 is in use and connected to the other party (step S68). If it is detected that any of the transmission terminals is already connected to the ISDN line 23 (step S68: Y), step S6
1 and the line connection request and the line connection permission read in step S63, a terminal to be connected to the line is specified, and this terminal is transmitted to the transmission selection register unit 5 via the N-bit internal bus 58.
The connection request terminal number is written in 1 (step S69).
Further, the N-bit transmission selection signal 30 is written in the transmission selection register 51 so that the transmission signal selection unit 25 switches to the line to be selected for transmission (step S70).
The operation permission signal 31 is output to the transmission signal selector 25 (step S71). Then, the line connection external request signal 45 is monitored again from the external operation unit 28 (return).

As described above, when the line is already connected, when the line connection permission is input from all the transmission terminals other than the transmission terminal which has output the line connection request, the transmission to the transmission terminal which has output the line connection request is performed. Perform line connection control. However, when the line connection permission has not been input from all the transmission terminals other than the transmission terminal that has output the line connection request, a transmission selection signal is output so as to directly select and transmit the line connected so far.

When it is detected in step S68 that the ISDN line 23 is not connected (step S68: N)
Is the dial signal 4 from the terminal that has output the line connection request.
Wait for 2 to be input (step S72: N). Each transmission terminal can monitor the line status display signal from the ISDN line interface unit 26 through a signal line (not shown), and monitors this signal to output a line connection request when the ISDN line 23 is not connected. The dial signal which is the previous line number is transmitted. When the dial signal 42, which is the line number of the other party, is input from the terminal that has output such a line connection request (step S72: Y), the line connection control signal 43 is output to the ISDN line interface unit 26. Then, after the predetermined line connection processing is performed, the external operation unit 28 monitors the line connection external request signal 45 again (return).

When it is determined in step S60 that the line connection external request signal 45 has been input from the external operation unit 28 (step S60: Y), the ISDN line interface is connected via the N-bit internal bus 56. Part 2
6 is referred to (step S7).
4), it is detected whether or not the ISDN line 23 is being connected (step S75). Here, when it is detected that the ISDN line 23 is being connected (step S75:
In step N59, by writing the connection request terminal number to the transmission selection register unit 51 in step S59, the line currently connected is allocated to the terminal corresponding to the line connection external request signal 45 input from the outside. To be able to The processing after step S59 is the same as the processing described so far.

Also, in step S75, the ISDN line 23
Is detected as being disconnected (step S7).
5: Y), it waits for external input dial signals 42 _{1 to} 42 _{N to} be input from the external operation unit 28 (step S7).
6: N). When an external input dial signal, which is the line number of the destination to which the line connection external request signal 45 is to be connected, is input from outside (step S76: Y), a new call is set up using this line number. To output the line connection control signal 43 to the ISDN line interface unit 26 (step S73). Thereafter, the line connection external request signal 45 is monitored again from the external operation unit 28 (return).

Next, an outline of the line disconnection processing performed by the central processing unit 50 will be described.

FIG. 6 shows a CP (not shown) of the central processing unit 50.
This shows an outline of the line disconnection process performed by U. First, it is determined whether or not the line disconnection external request signal 47 has been input from the external operation unit 28 (step S80). When it is determined that the line disconnection external request signal 47 has not been input from the external operation unit 28 (step S80: N), the disconnection request register unit 54 is read out via the N-bit internal bus 56 (step S80). Step S8
1) The first to Nth digital transmission terminals 21 to be connected
_It is detected whether there is a line disconnection request from any of _{1 to} 21 _N (step S82). Here, the transmission terminals 21 ₁ to
If it is detected that any one of 21 _N has a line disconnection request (step S82: Y), the disconnection permission register section 55 is read out via the N-bit internal bus 56 (step S83). In each transmission terminal, all transmission terminals other than the transmission terminal that transmitted the previous line disconnection request are notified as the other terminal line disconnection request signal 40. For example, each transmission terminal that has received the other terminal line disconnection request transmits If it has the information to be done, the line disconnection is not permitted. Otherwise, the line disconnection is permitted. In this way, a line disconnection permission signal indicating permission or non-permission of the line disconnection from the transmission terminal that has requested the line disconnection is input to the disconnection permission register unit 55 from each transmission terminal.

On the other hand, if there is no line disconnection request from any of the transmission terminals 21 _{1 to} 21 _{N in} step S82 (step S82).
82: the N) after the predetermined time T ₃ has elapsed, which is determined in advance (Step S84: Y) again from the outside of the operation portion 28 of the step S60 whether or not line disconnection external request signal 47 is input judge. In this way, unless the line disconnection external request from the outside, with reference to the disconnection request register unit 55 at a predetermined of T ₃ cycles line disconnection request signal 39 ₁
Monitor up to 39 _N.

In step S83, the disconnection permission register 5
5 is read, and it is detected whether or not there is a line disconnection permission (step S85). Here when all line disconnection permission from the transmission terminal other than transmission terminal which outputs a line disconnection request is not input: (step S85 N), the predetermined that predetermined time T ₄ after (Step S86 :
In Y), it is determined again whether or not the line disconnection external request signal 47 has been input from the external operation unit 28 in step S80. In this way, unless the line disconnection external request from the outside, if there is a line disconnection request, the predetermined T ₄ cycles with cutting enable register unit 55 with reference to line disconnection permission signal 41 ₁ to 41 _N and Perform monitoring.

When the line disconnection permission has been input from all the transmission terminals other than the transmission terminal that has output the line disconnection request in step S85 (step S85: Y), or the line disconnection external request 47 is received from the external operation unit 28. When the signal is input (step S80: Y), the line disconnection control signal 44 is output to the ISDN line interface unit 26 via the N-bit internal bus 56 (step S8).
7). Thereby, the ISDN line interface unit 26
Is disconnected by a predetermined line disconnection control. Thereafter, the line disconnection external request signal 47 from the external operation unit 28 is monitored again (return).

As described above, the central processing unit 5 of the device control unit 27
No. 0 executes the above-described line connection processing and line disconnection processing simultaneously or alternately.

Next, the operation of such a line controller will be described. First the first digital transmission terminal 21 ₁ will be described when the second digital transmission terminal 21 ₂ from the line connection request is sent during the line connection.

FIG. 7 shows a portion of the apparatus control section 27 shown in FIG. 3 which is related to the line connection processing. Transmitting data from the second digital transmission terminal 21 ₂ via the interface connection line 22 ₂ is input to the input-output interface unit 24. The output interface unit 24, is input to the transmission signal switching section 25 is converted from a signal level of the interface connection line device level as the transmission digital signal 29 _2. Therefore, the second
When the line connection request from the digital transmission terminal 21 ₂ is transmitted, but is input by the input-output interface unit 24 through an interface connection line 22 _2, output to the device control unit 27 so as line connection request signal 36 ₂ I do. In the device control unit 27, this is input to the connection request register unit 52. As described above, the first and third digital transmission terminal 21 _1, 21 ₃ through 21 _N, are simultaneously input line connection request signal 36 ₂ is another terminal line connection request signal 37, the respective terminal state Line connection permission signal 38 according to
_1, 38 _{3 ~38 N} is input to the connection permission register unit 53. The connection request register 52 and the connection permission register 53 are read by the central processing unit 50 at predetermined periods T ₁ and T ₂ , respectively. Connection request register section 52
Of the second digital transmission terminal 21 ₂
Upon detecting a line connection request signal 36 _second input from, by performing reading of connection permission register unit 53, it detects an input of the line connection permission signal 38 ₁ ~38 _N.

The central processing unit 50 receives the line connection permission signal 38 ₁
To 38 DEG _N input by detecting the in line connection permission signal 38 _1, 38 ₃ to 38 DEG _N all line connection permission from the first and the digital transmission terminal 21 ₁ of the third to N, 21 ₃ through 21 _N At some point, permission for line connection is determined. Then, the connection request terminal number is written to the transmission selection register unit 51 via the N-bit internal bus 56, and the transmission signal switching unit 25 is written.
, An N-bit transmission selection signal 30 is output. Moreover the central processing unit 50, for example, digital transmission terminal 21 of the _first and third to N, 21 ₃ through 21 line connection permission signal 38 ₁ from _N, 38 ₃ to 38 DEG _N transmission selection register section 5
1 and outputs an operation permission signal 31 to the transmission signal switching unit 25 when all the connections are permitted. In the transmission signal switching unit 25, the first digital transmission terminal 21 ₁
The transmission digital signal 29 ₁ from the second digital transmission terminal 21 ₂ is switched to the transmission digital signal 29 ₂ from the _second digital transmission terminal 21 _2, and is transmitted to the ISDN line interface unit 26 as the transmission switching digital signal 32. At this time,
If at least one of the first, third to Nth digital transmission terminals 21 ₁ , 21 _{3 to} 21 _N other than the _second digital transmission terminal 212 does not permit line connection, the central processing unit 50 of the device control unit 27. Does not write the line connection permission signal to the transmission selection register unit 51, and outputs the operation permission signal 31 to the transmission signal switching unit 25 with respect to the current line connection request from the _second digital transmission terminal 212. do not do. As a result, the transmission digital signal 29 of the _first digital transmission terminal 211 is directly used as the transmission switching digital signal 32.
Is output as

The transmission switching digital signal 32 is an ISDN
The signal is input to the line interface unit 26, and the I.T.T.
The frame is formed into a transmission line frame conforming to 430, converted to a transmission line signal level, and transmitted to the ISDN line 23.

Next, with reference to FIG. 7, description will be given of a case where the line has a first line connection request from the digital transmission terminal 21 ₁ is sent during the unconnected.

[0062] When the first line connection request from the digital transmission terminal 21 ₁ is output, the interface connection line 22 ₁
Via the input output interface unit 24, and outputs to the apparatus control unit 27 so as line connection request signal 36 _1. In the device control unit 27, the data is input to the connection request register unit 52. As described above, the line connection request signal 3 is simultaneously sent to the _{second to Nth} digital transmission terminals 21 _{2 to} 21 _N.
6 ₁ are inputted as the other terminal line connection request signal 37, the line connection permission signal 38 _{two or} three depending on the state of each terminal
8 _N is input to the connection permission register unit 53. The connection request register 52 and the connection permission register 53 are read out by the central processing unit 50 at predetermined periods T ₁ and T ₂ , respectively. Upon detecting a line connection request signal 36 of _the input from the transmission terminal 21 ₁ performs reading of connection permission register unit 53, the line connection permission signal 38 ₁
３８38 _N input is detected.

Each transmission terminal uses the ISD of the line controller 20.
A status display signal (not shown) from the N-line interface unit 26 can be monitored.
Since the N line 23 is adapted to recognize whether the potential or not connected in a connecting, lines of the destination together with the first digital transmission terminal 21 ₁ is the line connection request sent during line unconnected A dial signal, which is a connection number, is transmitted. This is input to the central processing unit 50 as a dial signal 42 _1. Therefore, the central processing unit 50 detects the input of the line connection permission signal 38 ₁ to 38 DEG _N, line connection permission signal 38 ₂ to 38 DEG _N all from the digital transmission terminal 21 ₂ through 21 _N of the second through N When the line connection is permitted,
It is determined that the line connection is permitted. And this dial signal 4
It sends out a line connection control signal 43 with respect to the ISDN line interface unit 26 based on the 2 ₁ to perform predetermined line connection processing.

Next, the first digital transmission terminal 21 ₁ will be described the case where the second line disconnection request from the digital transmission terminal 21 ₂ is sent during the line connection.

FIG. 8 shows a portion of the device control section 27 shown in FIG. 3 which is related to the line disconnection process. When the line disconnection request is sent from the second digital transmission terminal 21 _2, through the interface connection line 22 ₂ is inputted to the input-output interface unit 24, device control section so as line disconnection request signal 39 ₂ 27 Output to In the device control unit 27, this is the disconnection request register unit 5
4 is input. As described above, the first and third digital transmission terminal 21 _1, 21 ₃ through 21 _N, are simultaneously input line disconnection request signal 39 ₂ is another terminal line disconnection request signal 40, the respective terminal state The line disconnection permission signals 41 ₁ , 41 _{3 to} 41 _N are set in accordance with
Is input to The disconnection request register section 54 and the disconnection permission register section 55 are read out by the central processing section 50 at predetermined periods T ₃ and T ₄ , respectively. Upon detecting a line disconnection request signal 39 _second input from the transmission terminal 21 ₂ performs reading of cutting enable register section 55, it detects the input of the line disconnection permission signal 41 ₁ to 41 _N.

The central processing unit 50 outputs the line disconnection permission signal 41 ₁
To 41 _N input by detecting the, in digital transmission terminal 21 _1, 21 ₃ to 21 line disconnection permission signal 41 ₁ from _N, 41 ₃ to 41 _N are all line disconnection permission of the first and third to N In some cases, it is determined that the line disconnection is permitted, and a line disconnection control signal 44 is sent to the ISDN line interface unit 26 to perform a predetermined line disconnection process.

Next, a description will be given of line connection and line disconnection that can be forcibly performed by an external input from the operation unit 28. When the first line to the digital transmission terminal 21 ₁ is connected, the central processing unit 50 of the second digital transmission terminal 21 ₂ of the line connection request device control unit 27 by an external input means such as a keyboard of the operation unit 28 Is input as a line connection external request signal 45. The central processing unit 50 has priority over the line connection request signals 36 _{1 to} 36 _{N of the first} to Nth digital transmission terminals 21 _{1 to} 21 _N to be connected, and the lines from the other transmission terminals 21 _{1 to} 21 _N. Regardless of the connection permission signals 38 _{1 to} 38 _N , the connection request terminal number is forcibly written to the transmission selection register 51 via the N-bit internal bus 56, and N bits are transmitted to the transmission signal switching unit 25. The selection signal 30 is output. Further, the central processing unit 50 receives the line connection permission signal 3 from the first and third to Nth digital transmission terminals 21 ₁ , 21 _{3 to} 21 _N.
Writes 8 _1, 38 ₃ ~38 _N to the transmission selection register section 51, and outputs an operation permission signal 31 with respect to forcibly transmission signal switching section 25.

When the line is not connected, an arbitrary
Operates the line connection external request signal 45 of the digital transmission terminal
Input from the unit 28 to the central processing unit 50 of the device control unit 27
And the external input dial, which is the line connection number of the
The signal 46 is also input to the central processing unit 50. Again,
First to Nth digital transmission terminals 21 to be connected₁~ 2
1_NConnection request signal 36 from₁~ 36_NAnd line connection
Connection permission signal 38₁~ 38 _NISDN line regardless of
External input dial signal 4 for interface unit 26
Line connection control signal to perform connection processing for the line number 6
43 to perform a predetermined line connection process.

Further, at the time of line disconnection, even when an arbitrary digital transmission terminal is connected to the line, when the line disconnection external request signal 47 is input from the operation unit 28 to the central processing unit 50, the first to the first connected terminals are connected. N digital transmission terminal 21 regardless of ₁ to 21 line disconnection from _N request signals 39 ₁ ~ 39 _N and line disconnection permission signal 41 ₁ to 41 _N of performing line disconnection against forced ISDN line interface unit 26 Thus, the line disconnection control signal 44 is transmitted to perform a predetermined line disconnection process.

When such a line control device is applied to a monitoring system in which, for example, N digital transmission terminals are connected to a monitoring center by one line, the line control device has N lines at regular time intervals.
One transmission terminal repeats connection with the monitoring center by making a line connection request, or any transmission terminal that has detected a sensor such as an intruder should transmit the line connection request to the monitoring center by making a line connection request It can be transmitted instantly as information. As described above, by allowing a desired transmission terminal to instantaneously connect a line and transmit information to be transmitted, the monitoring system is improved in its monitoring capability.

As described above, when a line connection request is input to a line that is already connected by another transmission terminal, the line control device according to the first embodiment transmits signals other than the transmission terminal that has transmitted the line connection request. When the line connection is permitted from all the transmission terminals, the transmission data from the transmission terminal that has transmitted the line connection request can be transmitted using the already connected line. Also, when a line disconnection request is input to a line already connected by another transmission terminal, if all transmission terminals other than the transmission terminal that sent the line disconnection request have a line disconnection permission, this line is disconnected. Can be cut. Further, even when the line is not connected, when a line connection request is input, if the line connection is permitted from all the transmission terminals other than the transmission terminal that has transmitted the line connection request, the other party that has transmitted the line connection request simultaneously with the line connection request is transmitted. Line connection can be made to the previous line number.

Second Embodiment

In the line control device according to the first embodiment,
ISDN for N digital terminals connected
It was assumed that only one port was provided as a line interface. On the other hand, the line controller according to the second embodiment has N ports as ISDN line interfaces for N digital transmission terminals to be connected.

FIG. 9 shows an outline of the configuration of the line control device according to the second embodiment of the present invention. However, the same parts as those of the line control device according to the first embodiment shown in FIG. This second
The line control device 90 in the embodiment of FIG.
The difference from the line control device 20 in the embodiment of
The transmission signal switching section 91 is an N-input / N-output matrix switch. The transmission selection signal 30, the operation permission signal 31, and the output line selection signal 92 are input to change the transmission digital signals 29 _{1 to} 29 _N to the transmission switching digital signal 93 _1.
９３93 _N is output. Along with this,
A device control unit 94 for generating an output line selection signal 92 to be sent to the transmission signal switching unit 91, and an IS of _N transmission switching digital signals 93 _{1 to} 93 _N and ISDN lines 95 _{1 to} 95 _N
This is different from the ISDN line interface section 96 which interfaces with the DN line.

The output line selection signal generated by the device control unit 94
The transmission terminal 21 connected by the number 92₁~ 21_NFrom
Transmission digital signal 29₁~ 29_NAny ISDN times
Line 95₁~ 95_NIt is possible to send from. An example
For example, the first to Nth digital transmission terminals 21 to be connected
₁~ 21_NFor each ISDN line 95 ₁
~ 95_NIt is also possible to assign
A digital signal transmitted from another transmission terminal to the line that is communicating.
Can be sent. Output like this
The line selection signal 92 is the transmission selection signal in the first embodiment.
No. 30 and operation permission signal 31 are generated and transmitted at the same time.
The signal is input to the signal switching unit 91. That is, any Mth
Digital transmission terminal 21_MLine connection request signal input by
36_MAnd a dial signal 42 which is a line connection destination number._MYou
And the M-th digital transmission terminal 21_MAll biography except
Device control to receive line connection permission signal from sending terminal
The unit 94 includes the transmission terminal 21_MFrom all transmission terminals except
It is determined that the line connection is permitted by referring to the line connection permission signal of
And the line connection request signal 36_MDigital transmission sending
Terminal 21_MAnd the dial signal 42_MSend using
Transmission signal switching section 91 so as to select an ISDN line.
The transmission selection signal 30 and the operation permission signal 31,
A power line selection signal 92 is output.

The transmission switching digital signals 93 _{1 to} 93 _N output from the transmission signal switching section 91 are input to the ISDN line interface section 96, and the dial signals 42 _{1 to} 42 _N
Is transmitted through the interface unit selected by the user. A line connection request signal 36 ₁ ~ 36 _N, and the line connection permission signal 38 ₁ to 38 DEG _N from each terminal thereto, a dial signal 42 ₁ through 42 _N which is input at line not connected, the apparatus control unit 94, When the line connection is permitted from all the transmission terminals other than the transmission terminal that has requested the line connection, it is determined that the line connection is permitted, and the ISDN line interface unit 96 is determined based on the input dial signal. A line connection control signal 43 is transmitted to perform a predetermined line connection process.

When an arbitrary digital transmission terminal disconnects the line to which it is connected, the line disconnection request signals 39 _{1 to} 3 ₁
9 _N and the corresponding line disconnection permission signals 41 _{1 to} 41
_N and dial signals 421 to 42 _N are input. When it is determined that the line disconnection is permitted as in the first embodiment, the ISD selected by the dial signal is used.
The line disconnection control signal 44 is sent to the ISDN line interface unit 96 to perform predetermined line disconnection processing so as to perform disconnection control on the N lines.

[0078] Also, the operation unit 28, by entering a line connection external request signal 45 and the line connection destination of the external input dial signal 46, line connection request signal 36 ₁ ~ 36 _N and line connection permission from the transmission terminal regardless of the signal 38 ₁ ~38 _N, it is possible to perform a forced selection switch and connection of the line. Further, by inputting the line disconnection external request signal 47, the line disconnection request signal 3
Regardless of 9 _{1 to} 39 _N and the line disconnection permission signals 41 _{1 to} 41 _N , the line can be forcibly disconnected.

[0079] Now, transmission digital signal 29 ₁ from a first digital transmission terminal 21 ₁ is in line connection with the ISDN line 95 _1, and transmits the digital signal 29 ₂ from the second digital transmission terminal 21 ₂ Is ISDN line 9
It assumed to be in line connection with 5 _2. Furthermore, where when the line connection request signal 36 ₂ from the second digital transmission terminal 21 ₂ to the dial signal 42 ₂ is ISDN line 95 ₁ of the line number is entered, the digital first and third to N transmission terminals 21 _1, 21 ₃ to 21 line connection permission signal 38 ₁ from _N, 38 ₃ to 38 DEG _N are all assumed to be line connection permission. Then, transmission digital signal 29 ₂ is transmitted selectively transmitted signal from the signal switching unit 91 so as to be outputted selected as the transmission switching digital signals 93 ₁ 30 and the operation permission signal 3 from the second digital transmission terminal 21 ₂
1, by outputting the output line selection signal 92 can send the transmission data from the second digital transmission terminal 21 ₂ from the ISDN line 95 _1. At this time, when the first digital transmission terminal 21 ₁ inputs the line connection request signal 36 ₁ and the dial signal 42 ₁ which is a line number other than the ISDN line 95 ₁ , when the line connection is permitted from all the remaining transmission terminals, 1st digital transmission terminal 21 ₁
Transmission data from ISDN other than ISDN line 95 ₁
It is possible to transmit from a line.

As described above, the line control device according to the second embodiment, when a line connection request and a dial signal are input to a line already connected by another transmission terminal,
If there is a line connection permission from all transmission terminals other than the transmission terminal that sent the line connection request, the transmission data from the transmission terminal that sent this line connection request is transmitted using the already connected line or any line. I can do it. This makes it possible to allocate one ISDN line to one digital transmission terminal, or to transmit a transmission digital signal of another terminal to a line where an arbitrary transmission terminal is communicating. Therefore, for example, the first digital transmission terminal 21 ₁ is connected to the ISDN line 95 ₁
When communicating using, by the second digital transmission terminal 21 ₂ is connected request, when the first digital transmission terminal 21 ₁ permits the connection, for receiving the output line selection signal 92 , The second digital transmission terminal 21
₂ of a transmission digital signal 29 ₂ so that it is possible to sent to the ISDN line 95 _1. In this case, ISDN
Since the line disconnection and connection processing is not required, the effect that the overhead of the disconnection and connection processing can be omitted and information can be transmitted from another terminal instantly can be obtained.

In the first and second embodiments, the transmission digital signal is transmitted to the ISDN line as an example of the line. However, the line is not limited to the ISDN line.

In the first and second embodiments, when the transmission terminal which has received the line connection request as the other terminal line connection request has information to be transmitted, the line connection is not permitted and the transmission is performed as it is. In this case, it is assumed that the line connection is requested and the line connection is permitted at other times.However, for example, at this time, the line connection must be permitted according to a predetermined priority in the line connection request. Can also. According to this priority, line switching is forcibly performed even if there is information to be transmitted to the transmission terminal that has received the other terminal line connection request, and transmission digital signals from the transmission terminal with higher priority are quickly transmitted. It is possible to transmit to.

[0083]

As described above, according to the first aspect of the present invention, a line connection request sent from an arbitrary transmission terminal among a plurality of transmission terminals to be connected, and a line connection request sent from all the remaining transmission terminals to the line connection request. When the transmitted line connection permission is received, the transmission signal of the transmission terminal which has transmitted the line connection request is transmitted to the line. This makes it possible to connect a plurality of points to one point in a very simple configuration in a time-division manner and quickly in a line connection. further,
By adopting the sequence of request and permission, transmission can be switched by a request of the transmission terminal according to the state of a plurality of transmission terminals having different transmission purposes for each transmission system. Furthermore, since the central station can connect the line to each transmission terminal when necessary without connecting and disconnecting the line to each transmission terminal at any time as in the related art, the load of the monitoring process is dispersed. It is also possible.

According to the second aspect of the present invention, the connection
When receiving a line disconnection request transmitted from an arbitrary transmission terminal among the plurality of transmission terminals and a line disconnection permission transmitted from all the remaining transmission terminals corresponding thereto, the line being connected is disconnected. did. Thereby, even if another transmission terminal is using the line, the line can be disconnected only when permitted by all the remaining terminals in response to a new line connection request from another transmission terminal. This eliminates the need for the central office to perform line disconnection processing for each transmission terminal from time to time as required in the related art, and allows the line to be used only when necessary, thereby improving line utilization efficiency. . By combining with the invention described in claim 1, even if it is necessary to reconnect to another line at the time of line connection, the line is temporarily disconnected only by processing from the transmission terminal that requested the line connection, and further to the desired line Reconnection is also possible.

Further, according to the third aspect of the present invention, by using a plurality of lines and specifying them by line numbers, one ISDN line can be assigned to one transmission terminal, or an arbitrary transmission terminal can be assigned. It is also possible to transmit a transmission digital signal of another terminal to a line under communication, thereby improving the flexibility of a transmission system to which a line control device is applied. Furthermore, since the connection processing of the ISDN line is not required, the effect that the overhead of the connection processing can be omitted and information can be transmitted from another terminal instantaneously can be obtained.

Further, according to the fourth aspect of the present invention,
By using a plurality of lines and specifying them by line numbers, one ISDN line can be assigned to one transmission terminal, or a transmission terminal of another transmission terminal can transmit a line to which a transmission terminal is communicating. A digital signal can be transmitted, and the flexibility of a transmission system to which the line control device is applied can be improved. Further, since the disconnection processing of the ISDN line is not required, the effect that the overhead of the disconnection processing can be omitted and information can be transmitted from another terminal instantaneously can be obtained.

Further, according to the invention described in claim 5, by making it possible to forcibly make a line connection from the outside, it is possible to make an emergency line connection,
Maintainability can be improved.

Further, according to the invention described in claim 6, by making it possible to forcibly disconnect the line from the outside, an emergency line disconnection can be performed.
Maintainability can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an outline of a configuration of a line control device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating an outline of a configuration of a transmission signal switching unit according to the first embodiment.

FIG. 3 is a block diagram illustrating an outline of a configuration of a device control unit according to the first embodiment.

FIG. 4 is a flowchart showing an outline of a line connection process at the time of an external line connection request in the first embodiment.

FIG. 5 is a flowchart showing an outline of a line connection process other than when an external line connection is requested in the first embodiment.

FIG. 6 is a flowchart showing an outline of a line disconnection process in the first embodiment.

FIG. 7 is an explanatory diagram for explaining a line connection operation in the first embodiment.

FIG. 8 is an explanatory diagram for explaining a line disconnection operation in the first embodiment.

FIG. 9 is a block diagram illustrating an outline of a configuration of a line control device according to a second embodiment of the present invention.

FIG. 10 is a block diagram showing an outline of a configuration of a conventionally proposed line control device.

[Explanation of symbols]

Reference Signs List 20 line control devices 21 _{1 to} 21 _N first to Nth digital transmission terminals 22 _{1 to} 22 _N interface connection lines 23, 95 _{1 to} 95 _N ISDN lines 24 input / output interface units 25, 91 transmission signal switching units 26, 96 ISDN line interface unit 27, 94 Device control unit 28 Operation unit 29 _{1 to} 29 _N Transmission digital signal 30 Transmission selection signal 31 Operation permission signal 32, 93 _{1 to} 93 _N Transmission switching digital signal 33 N input 1 output selector circuit 34 Selection output Switching unit 35 Received digital signal 36, 36 _{1 to} 36 _N line connection request signal 37 Other terminal line connection request signal 38, 38 _{1 to} 38 _N line connection permission signal 39, 39 _{1 to} 39 _N line disconnection request signal 40 Other terminal line disconnection request signal 41, 41 ₁ to 41 _N line disconnection permission signal 42, 42 ₁ through 42 _N dial signal 4 Line connection control signal 44 line disconnection control signal 45 line connecting the external request signal 46 external input dial signal 47 Line disconnection external request signal 92 output line selection signal

Claims (6)

(57) [Claims] 1. A line connection request receiving means for receiving a line connection request sent from a first transmission terminal to be connected and a line number for which the connection is requested, and said first connection terminal out of a plurality of connected transmission terminals Line connection permission receiving means for receiving a line connection permission indicating whether to permit the line connection request of the first transmission terminal in response to the line connection request from another transmission terminal other than the transmission terminal; Line connection permission for determining whether or not line connection permission for permitting the line connection request has been received from all the transmission terminals except the first transmission terminal with reference to the line connection permission received by the connection permission receiving means. Determination means; line connection detection means for detecting whether a predetermined line to be connected is being connected; and line connection permission by the line connection permission determination means except for the first transmission terminal. Is determined from the transmission terminal has been received, and the predetermined by the line connection detecting means
A transmission signal transmitting unit for transmitting a transmission signal from the first transmission terminal to the predetermined line when it is determined that the line is being connected; and It is determined to be received from all transmission terminals except the transmission terminal, and the predetermined by the line connection detecting means
Line when the line is determined not to be in connection for connecting setting of the line for transmitting a transmission signal from the first transmission terminal in response to the received line number by the line connection request receiving means A line control device comprising: connection setting means. 2. A first and a line disconnection request receiving means for receiving the sent line disconnection request from the transmission terminal, all other except for the first transmission terminal from among the plurality of transmission terminals connected to be connected A line disconnection permission receiving means for receiving a line disconnection permission indicating whether or not to permit the line disconnection request of the first transmission terminal in response to the line disconnection request from the transmission terminal; Line disconnection permission determining means for determining whether or not line disconnection permission for permitting the line disconnection request has been received from all transmission terminals except the first transmission terminal with reference to the received line disconnection permission; A line disconnecting means for disconnecting the connected line when the line disconnection permission determining means determines that the line disconnection permission has been received from all of the transmission terminals except the first transmission terminal; A line control device characterized by the above-mentioned. 3. The line connection request receiving means receives a line connection request sent from a first transmission terminal to be connected and a line number requesting the line connection, and the transmission signal sending means receives the line connection permission. When the determination unit determines that the line connection permission has been received from all the transmission terminals except the first transmission terminal, and when the line connection detection unit determines that the line is being connected, a plurality of connected lines are determined. A transmission signal from the first transmission terminal is transmitted from the line to a line corresponding to the line number received by the line connection request receiving unit, and the line connection setting unit sets the line connection permission by the line connection permission determination unit. The first
Are determined to be received from all transmission terminals except for the transmission terminal, and when the line connection detecting means determines that the line is not being connected, the lines received by the line connection request receiving means from a plurality of lines. 2. The connection setting of a line corresponding to a number is performed.
The line control device as described above. 4. The line disconnection request receiving unit receives a line disconnection request sent from a first transmission terminal to be connected and a line number requesting the line disconnection, and the transmission signal transmitting unit receives the line disconnection permission. When the determination unit determines that the line disconnection permission has been received from all the transmission terminals except the first transmission terminal, the line being connected corresponding to the line number received from the plurality of lines by the line disconnection request reception unit 3. The line control device according to claim 2, wherein the line controller is disconnected. 5. A line connection request input means for externally inputting a line connection request of any transmission terminal among a plurality of transmission terminals to be connected and a line number for which the connection is requested,
The transmission signal transmitting means determines that the line is being connected by the line connection detecting means when the line connection request input means inputs a line connection request from outside, regardless of the determination result by the line connection permission determining means. When the line connection request is input, a transmission signal from the transmission terminal requesting the line connection is transmitted to the line by the line connection request input unit, and the line connection setting unit receives a line connection request from the outside by the line connection request input unit. When the line connection detecting means determines that the line is not connected regardless of the determination result by the line connection permission determining means, the transmission signal from the transmission terminal which has requested the line connection by the line connection request input means is transmitted. A connection setting for a line corresponding to the line number for transmission. Claim 1 or claim 3 line controller according. 6. A line disconnection request input means for externally inputting a line disconnection request of an arbitrary transmission terminal out of a plurality of connected transmission terminals, wherein said line disconnection means is externally operated by said line disconnection request input means. 5. The line control according to claim 2, wherein when the line disconnection request is input, the line requested by the line disconnection request inputting unit is disconnected irrespective of the judgment result by the line disconnection permission judging unit. apparatus.