JP3306897B2 - Network control device and connection destination identification method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network control device for connecting a data communication terminal such as a facsimile or a computer to an analog line such as a telephone line. The present invention also relates to a network control device capable of flexibly coping with the network control device and a connection destination identifying method thereof.

[0002]

2. Description of the Related Art When a data communication terminal such as a facsimile or a computer is connected to an analog line such as a public telephone line, a network control device (modem) is provided between a modem for performing analog / digital conversion of data and the line. NCU: N
network control unit), the network control device performs activation and restoration of the switching equipment of the data communication service station, transmission of a selection signal, confirmation of a response to a called party, and the like.

A data communication terminal may be used by being connected not only to an external line (analog line) such as a public telephone line but also to an extension (analog line) such as a private line for private use. As described in the gazette, a network control device for selectively connecting a facsimile or the like to either an outside line or an inside line has been developed.
In this network control device, identification of a first line connection unit accommodating one line of either an outside line or an extension and a second line connection unit accommodating two lines of both an outside line and an extension is automatically performed. And a line control unit for performing line control corresponding to the identified line connection unit. This allows
Regardless of which of the first and second line connection units is used, the same line control unit can cope with this, and it is possible to reduce the cost of the network control device.

In this network control device, the first line connection unit and the second line connection unit are identified based on the DC state of the accommodated line detected at each line connection unit. That is, a terminal for detecting the DC state of an unaccommodated line is provided in the first line connection unit, the output state of this terminal is set to a fixed value, and this fixed output is detected. Is identified. If a signal other than a fixed output is detected at the corresponding terminal, the terminal is identified as a second line connection unit.

[0005] However, in recent years, in order to reduce the number of control signals, a network control device has provided a multiplexer or the like on the second line connection unit to connect to the line control unit. For this reason, in the conventional second line connection unit,
The terminals for detecting the DC state of the lines provided for the respective accommodated lines are integrated into one, and have the same number as the first line connection unit. That is, even in the second line connection section, there is no terminal for detecting the DC state of the second analog line. Therefore, in such a network control device, in order to identify the line connection as in the prior art, it is necessary to provide a multiplexer and the like on the first line connection only for the purpose of identification.

[0006]

A problem to be solved is that, in a network control device provided with a multiplexer for reducing control signals, a terminal for detecting a DC state of a line at a second line connection is provided. , The same number as that of the first line connection unit. When the first line connection unit is distinguished from the second line connection unit by the conventional technology, the first line connection unit In addition, it is necessary to provide a multiplexer and the like, which is very uneconomical in terms of cost. An object of the present invention is to solve these problems of the prior art,
Automatic identification of the second line connection unit having the same number of terminals for detecting the DC state of the line and the first line connection unit by a multiplexer or the like is performed without increasing the cost. An object of the present invention is to provide a network control device capable of reducing the number of lines and increasing the efficiency of line control, and a method of identifying a connection destination.

[0007]

In order to achieve the above object, a network controller according to the present invention has the following features. (1) A first network controller accommodates one analog line and outputs a DC state of the analog line.
A second line connection unit that accommodates two analog lines and outputs a DC state of each analog line, and a first line connection unit and a second line connection unit based on the DC state. And a line control unit that performs line control corresponding to the first line connection unit or the second line connection unit based on the result of the identification. The second line connection unit selectively transmits the DC states of the two analog lines to the line control unit via the same terminal in response to the input of the first selection control signal from the line control unit. And the second from the line control unit.
In response to the selection control signal input, a DC state output control unit that sends a specific DC state that does not correspond to any of the two analog lines to the line control unit via the same terminal,
The line control unit is connected to an input terminal for inputting a DC state from the connected first line connection unit or the second line connection unit, and to the input terminal when the second selection control signal is output. It is characterized by comprising a connection destination identification unit that identifies a connection destination to one of a first line connection unit and a second line connection unit based on an input DC state. (2) In the network control device according to (1), the DC state output control unit includes a multiplexer. Further, (3) the above (1) or (2)
In the connection destination identification method of the network control device according to any one of the above, the connection destination identification unit, when outputting the second selection control signal,
A DC state input to the input terminal is detected, and if the detected DC state is a specific DC state from the DC state output control section of the second line connection section, the second line connection section is connected. If it is not a specific DC state,
The first line connection unit is identified as connected.

[0008]

In the present invention, if the second line connection unit is connected to the line control unit, the transmitted second selection control signal is transmitted.
The DC state input from the DC state output control unit such as the multiplexer in response to the above is a specific DC state different from any of the external line and the internal line. Further, if the first line connection unit is connected to the line control unit, the DC state input in response to the transmitted second selection control signal is any one of the external line and the internal line. . In this way, the line control unit can detect the DC state at the time of transmitting the second selection control signal, thereby identifying the line connection unit configured to transmit the DC state from the same terminal. The control unit can perform the line control processing as before.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the configuration according to the present invention of the network control device of the present invention. The network control device 1a of this embodiment is connected to a telephone 2 and a facsimile machine 3 with a built-in modem (not shown). The network controller 1a accommodates two lines of external lines 4a, 4b and extensions 5a, 5b. Selection processing of the second line connection unit 6a to be connected, external lines 4a and 4b and extensions 5a and 5b, automatic arrival / departure processing for the selected line, and selective connection of the selected line to the facsimile 3 of the telephone 2 And a line control unit 7 for performing processing. The line connection unit 6a and the line control unit 7 exchange various signals via the signal lines 8a to 8h. For example, in the signal lines 8a and 8b,
The signals with the external lines 4a and 4b are the signal lines 8c and 8d, the signals with the internal lines 5a and 5b are, the signal lines 8e and 8f are the DC states of the external lines 4a and 4b and the internal lines 5a and 5b, and the signal lines. 8g and 8h, the line control unit 7 sends the signal to the line connection unit 6
A selection control signal to a is exchanged. The line connection unit 6a selects one of the DC states of the external lines 4a, 4b and the internal lines 5a, 5b based on the first selection control signal sent from the line control unit 7 via the signal line 8g. do it,
The signal is sent to the line controller 7 via the signal lines 8e and 8f, and based on the second selection control signal sent from the line controller 7 via the signal line 8h, the outer lines 4a and 4b and the inner lines 5a and A multiplexer 9 is provided as a DC state output control unit for selecting a specific DC state different from any of the DC states 5b and transmitting the selected DC state to the line control unit 7 via the signal lines 8e and 8f. Further, the line control unit 7 sends out a first selection control signal to the multiplexer 9 via the signal line 8g, and based on the DC state sent via the signal lines 8e and 8f, the external lines 4a and 4b. And which one of the extensions 5a and 5b is connected, sends a second selection control signal to the multiplexer 9 via the signal line 8h, and outputs a signal line corresponding to the second selection control signal. 8e, 8
external lines 4a and 4b and internal lines 5a and 5
a connection destination identification unit for identifying that the connection destination is the second line connection unit based on a specific DC state different from either of the above.

As described above, by providing the connection destination identifying section 10 in the line control section 7, the network control apparatus 1a of the present embodiment is provided.
Is equipped with a multiplexer 9 and can identify the line connection unit 6a configured to transmit a DC state from the same terminal. If the connection destination is the first line connection unit that can accommodate only one of the outside lines 4a and 4b or the inside lines 5a and 5b, as shown in FIG. , A second selection control signal is transmitted through the signal line 8e, corresponding to the second selection control signal.
8f is not a specific DC state, but is an external line 4a, 4b or an internal line 5a, 5b.
It corresponds to either of the above. Thus, the line control unit 7 identifies that the connection destination is the first line connection unit.

FIG. 2 is a block diagram showing a second embodiment of the configuration according to the present invention of the network control device of the present invention. The network control device 1b of the present embodiment is different from the network control device 1a in FIG.
Similarly to the above, a line control unit 7 connected to the telephone 2 and the facsimile 3 and having a connection destination identification unit 10 is provided.
In place of the second line connection unit 6a in FIG. 1, a first line connection unit 6b for accommodating one of an outside line and an inside line is provided. In this embodiment, the outside lines 4a and 4b are accommodated. Further, the line connection unit 6b and the line control unit 7
1 via signal lines 8a to 8h.
The same signals are exchanged as in a. Line connection unit 6b
Accommodates only one of the external lines 4a and 4b, and is not provided with a DC state output control unit such as the multiplexer 9 included in the line connection unit 6a in FIG. For this reason, even if the connection destination identification unit 10 of the line control unit 7 sends out the second selection control signal via the signal line 8h, the line connection unit 6b
And the DC state output to the signal lines 8e and 8f does not change. As described above, when the DC state output to the signal lines 8e and 8f does not indicate a specific DC state when the second selection control signal is transmitted, the connection destination identification unit 10 causes the first line connection unit 6b Can be identified as being connected.

FIG. 3 is a circuit diagram showing an embodiment of the internal configuration according to the present invention of the second line connection unit in FIG. In the second line connection unit 6b of the present embodiment, the external line 4
Signals on a and 4b are exchanged on signal lines 8a and 8b via a switch 11 for opening and closing the external lines 4a and 4b, a resistor 13 and a transformer 12. This resistance 1
3, a photocoupler 14 and a resistor 15 are connected in parallel, and the output of the photocoupler 14 is a pull-up resistor 2
7 and 28 and the waveform shaping circuits 16 and 17 are input to the multiplexer 9. Similarly, the signal on extensions 5a and 5b is a switch 2 for closing extensions 5a and 5b.
0 and the signal line 8 via the resistor 22 and the transformer 21.
c and 8d, a photocoupler 23 and a resistor 24 are connected in parallel to the resistor 22.
The output of 3 is input to the multiplexer 9 via the pull-up resistors 27 and 28 and the waveform shaping circuits 25 and 26. Here, the multiplexer 9 uses the first selection control signal from the signal line 8g to determine which of the signals input from the waveform shaping circuits 16 and 17 or the signals input from the waveform shaping circuits 25 and 26 the signal line. 8e and 8f are selected. In addition, the multiplexer 9 causes the signal line 8e, the signal line 8e, by the second selection control signal from the signal line 8h.
At 8f, a signal (DC state) of a specific level different from the signals input from the waveform shaping circuits 16 and 17 and the waveform shaping circuits 25 and 26 is output. Using the signal of this specific level as an input, the line control unit 7 in FIG. 1 can identify the connected second line connection unit 6b.

FIG. 4 is a circuit diagram showing one embodiment of the internal configuration of the first line connection unit in FIG. The first line connection unit 6b of this embodiment accommodates only one line of the external lines 4a and 4b, and the signals on the external lines 4a and 4b
The signal is transmitted and received via signal lines 8a and 8b via a switch 41 for opening and closing 4b, a resistor 43 and a transformer 42. The resistor 43 includes a photocoupler 44 and a resistor 45.
Are connected in parallel, and the outputs of the photocoupler 44 are sent to the signal lines 8e and 8f via the pull-up resistors 48 and 49 and the waveform shaping circuits 46 and 47, respectively. Here, the signal lines 8g and 8 for the first selection control signal and the second selection control signal sent from the line control unit 7 in FIG.
Since h is open, the signals on the signal lines 8e and 8f always indicate the DC state of the external lines 4a and 4b. Thereby, the line control unit 7 in FIG. 1 can identify the connection of the first line connection unit 6b. Here, the symbol lines 8c and 8d are connected to the transformer 40 whose primary side is open.

FIG. 5 is an explanatory diagram showing one embodiment of the operation of the connection destination identification unit in FIG. 1 according to the present invention. The drawing shows signal lines 8e corresponding to the signal lines 8g and 8h indicating the states of the output first selection control signal and second selection control signal.
FIG. 5A is an output table of FIG.
5 (b) corresponds to the first line connection unit 6b in FIG. When the signal line 8g is "L" (low), it is in the external line DC state detection mode, and when it is "H" (high), it is in the internal line DC state detection mode. Then, the case where the signal line 8h is “H” is the connection destination detection mode. First, when the signal line 8h is “L”, the signal line 8g corresponds to the “L” and “H” states of the signal line 8g in both of FIGS. 5A and 5B. The outputs of 8e and 8f are any combination of "H" and "H", "L" and "H", and "H" and "L". In FIG. 5B, when the first line connection unit 6b is connected to an external line as shown in FIG. 2, the internal DC state has no meaning. Next, when the signal line 8h is at “H”, the connection destination detection mode is set. At this time, as shown in FIG. 2, when the first line connection unit 6b is connected to the line control unit 6,
Since the signal lines 8e and 8f cannot be at the low level at the same time, an external DC state is always output to the signal lines 8e and 8f. In FIG. 5B, the signal lines 8e and 8f
Any combination of “H” and “H”, or “L” and “H”, or “H” and “L”. However, FIG.
In (a), the signal lines 8e and 8f both become "L". As described above, in a state where both of the signal lines 8e and 8f are "L", the connection destination identification unit 10 in FIG. 1 sets the second line in FIG. The connection part 6a is identified.

FIG. 6 is a flowchart showing the connection destination identifying operation of the line control unit in FIGS. 1 and 2 according to the present invention. First, a second selection control signal is transmitted by the connection destination identification unit 10 in FIGS. 1 and 2, the signal line 8h is activated (high) (step 601), and the signal states of the signal lines 8e and 8f at this time point (Step 60)
2) The respective signal states of the input signal lines 8e and 8f are detected (step 603). Here, the signal lines 8e,
If both 8f are low level, it is determined that the second line connection unit accommodating two lines is connected, and control corresponding to accommodating two lines is performed (step 604). If the signals on the signal lines 8e and 8f are not at the low level, it is determined that the first line connection unit accommodating only one line is connected, and control corresponding to accommodating one line is performed. (Step 605).

As described above with reference to FIGS. 1 to 6, in the network control device of the present embodiment, when the second selection control signal is transmitted, two signal lines indicating the DC state from the line connection unit are provided. However, only when both become low level, it is identified that the second line connection unit accommodating two lines is connected, otherwise, the first line connection accommodating only one line is connected. The unit is identified as connected. Thus, even if the second line connection unit accommodating two lines includes a multiplexer or the like and is configured to reduce the number of control signals, the line control unit determines which of the first and second line connection units is used. The connection can be automatically identified without increasing the cost.
The present invention is not limited to the embodiment described with reference to FIGS.

[0017]

According to the present invention, a second system for accommodating two lines is provided.
Even if the number of the terminals for detecting the DC state of the line of the line connection unit becomes equal to the number of the first line connection units accommodating only one line by providing a multiplexer or the like, the first Since the first line connection unit and the second line connection unit can be identified without providing a multiplexer or the like on the line connection unit, it is possible to increase the efficiency of line control without increasing costs.

[0018]

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a configuration according to the present invention of a network control device of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the configuration according to the present invention of the network control device of the present invention.

FIG. 3 is a circuit diagram showing one embodiment of an internal configuration according to the present invention of a second line connection unit in FIG. 1;

FIG. 4 is a circuit diagram showing one embodiment of an internal configuration of a first line connection unit in FIG. 2;

FIG. 5 is an explanatory diagram showing one embodiment of the operation of the connection destination identification unit in FIG. 1 according to the present invention.

FIG. 6 is a flowchart showing an operation of the line control unit in FIGS. 1 and 2 according to the present invention.

[Explanation of symbols]

 1a, 1b Network control device 2 Telephone 3 Facsimile 4a, 4b Outside line 5a, 5b Extension 6a Second line connection unit 6b First line connection unit 7 Line control unit 8a to 8h Signal line 9 Multiplexer 10 Connection destination identification unit 11 Switch REFERENCE SIGNS LIST 12 transformer 13 resistor 14 photocoupler 15 resistor 16, 17 waveform shaping circuit 18, 19 pull-up resistor 20 switch 21 transformer 22 resistor 23 photocoupler 24 resistor 25, 26 waveform shaping circuit 27, 28 pull-up resistor 40 transformer 41 switch 42 transformer 43 resistor 44 photo coupler 45 resistor 46, 47 waveform shaping circuit 48, 49 pull-up resistor

Claims (3)

(57) [Claims] A first line connection means for accommodating one analog line and outputting a DC state of the analog line, and a second line for accommodating two analog lines and outputting a DC state of each analog line. and line connection means, it is properly also on SL first line connecting hands stage a network control unit comprising a circuit control means for line control corresponding to the second line connection means, the second line connection means Responding to the input of the first selection control signal from the line control means, selectively transmitting the DC state of the two analog lines to the line control means via the same terminal, In response to the input of the second selection control signal from the line control means, a specific DC state not corresponding to any of the two analog lines is transmitted to the line control means via the same terminal. DC status output Comprising a control means, said first line connection means, on from the line control unit
The input of the first selection control signal and the second selection control
The same DC state is applied to any of the signal inputs
Means for sending to the control means, the line control means comprising: an input terminal for inputting a DC state from the connected first line connection means or the second line connection means; when the output of the selection control signal, if the specific DC state is inputted to the input terminal
Identify that the second line connection means is connected, and
If the specified DC status is not input to the input terminal,
Connection destination identification means for identifying that the first line connection means is connected , wherein the identification result of the connection destination identification means is
The first line connection means or the second circuit
A network control device for performing line control corresponding to line connection means . 2. The network control device according to claim 1, wherein said DC state output control means comprises a multiplexer.
The multiplexer receives a DC state of one of the two analog lines.
1, a third input for inputting the second input terminal and the other DC state
4 and the input of the first selection control signal.
Correspondingly, the pair of the first and second input terminals or the
A third output terminal that outputs any of the inputs of the fourth input terminal set;
A first output terminal , a second input terminal, and the third and fourth input terminals.
In the pair of power terminals, as the DC state of the analog line,
"H (high)", "L (low)", "L (low)"
"H (high)", "H (high)" and "H (high)"
Entered by a combination of Zureka, in response to input of the first selection control signal "H"
Any of "L", "L" and "H", "H" and "H"
Output from the first and second output terminals in combination, and output “L” in response to the input of the second selection control signal.
The combination of "L" as the specific DC state
1, a network control unit according to claim also be output from the second output terminal. 3. An analog circuit for accommodating one analog line.
First line connection means for outputting a DC state of the
Accommodates two analog lines, one for each analog line
A second line connection means for outputting a DC state;
The first line connection means and the second line connection
Of which means are connected, and based on the result of the identification,
The first line connection means or the second line
Line control means that performs line control corresponding to the connection means
Additional Ranaru network control apparatus first line connection means and the second round
Der way to identify which is connected to one of the lines connecting means
And Tsu, in the second line connection means, or the line control unit
In response to the input of the first selection control signal,
Select the DC status of the analog line via the same terminal selectively.
And sends it to the line control means.
Corresponding to the input of the second selection control signal from the means,
A specific direct current that does not correspond to either of the two analog lines
The status is sent to the line control means via the same terminal.
Out, in the first line connection means, or the line control unit
Input of the first selection control signal and the second selection
The same DC state for any of the control signal inputs.
Sent to the serial channel control means, in the line control hand stage, when the output of the second selection control signal, the DC state of the upper Kitoku constant is input to the second
Identifies that the line connection means are connected, the connection destination network controlling apparatus characterized by identifying the upper Symbol first line connection means is connected if the specific DC state is entered Identification method.