JPS62234453A - Terminal extending system for plural-terminal storing line interface device - Google Patents

Abstract

PURPOSE:To easily increase the number of ports without extending any subscrib er line and to increase the degree of freedom for system constitution with a plural-terminal storing line interface device, by cascading a telephone type terminal including said interface device to a connection terminal via a telephone line. CONSTITUTION:A line interface device 2M set at the master side is connected to a line interface device 2S set at the slave side via a telephone line TL. Thus the number of terminals are increased. In other words, the line TL for extension and the dievice 2S cen be regarded as a telephone type terminal to the device 2M of the master side. The same relation is secured also when another line interface device is connected to a connection terminal for 2-wire communication terminal of the device 2S of the slave side. Thus the subscriber lines can be increased just with a mere telephone line without increasing the subscriber lines and in the same hardware structure. Thus the terminals can be extended easily and economically.

Description

Detailed Description of the Invention [Field of Industrial Application] This invention relates to a telephone line, a telephone line, a plurality of telephones, a facsimile communication terminal, a 1117 image communication terminal, and a ringless communication terminal (hereinafter collectively referred to as telephone-type communication terminals). (also referred to as a terminal) and at least one data terminal such as a personal computer (also referred to as a non-telephone type terminal), and is capable of selectively connecting to other external terminals. (hereinafter also simply referred to as a line interface device), and particularly relates to a method for adding terminals in such a line interface device. [Prior Art] As a method of installing a data terminal equipment (also abbreviated as DTE in the US) on a telephone line, for example, the method shown in FIG. 4 is known. In addition, in the same figure, 1 is a telephone exchange;
3C is a telephone, 5C is a DTE, 7 is a converter, 22 is a network control unit δ (NCU), 25 is a modem unit (MODEM)
), i4 is a telephone line.

This translates to <DTE>tlL! as shown in the figure. By R57 “
This method is to install it as a "telephone connection device."

Here, converter 7 connects telephone line 14. It is connected to the telephone set 3C and the data terminal 5C, and serves to connect the line 14 to the telephone set 3C or to the terminal 5C by manual operation of the converter 70.

However, since this method relies on manual operation of the converter 7, "telephone calls" and "data communications" are semi-fixed, resulting in various inconveniences. For this reason, recently, telephones with modems (with a built-in network control unit (NCU)) have appeared.

FIG. 5 is a schematic diagram showing a model 1 attached telephone.

Note that each symbol indicated by \ is the same as in Fig. 4, and T
5 is a connection terminal (also called a boat).

That is, this telephone with a modem has a port (terminal T5) for accommodating a DTE, and facilitates connection of the terminal 5C. In this case, the NCU 22 is provided with this function so that the switching operation between the telephone 3C and the terminal 5C is automatically performed, so that "call" and "communication" are not semi-fixed.

[Problem that the invention seeks to solve]

However, the number of terminals that can be installed on such a modem-equipped telephone is limited by cost and manufacturing constraints, so if a large number of boats are required, similar modem-equipped telephones must be added. . In other words, each time an additional telephone line is installed, additional telephone lines must be added, resulting in a problem of extremely high costs.

Therefore, this invention makes it possible to perform telephone communication and data communication without making them semi-fixed, and also makes it easy to expand or increase the number of boats without adding any telephone lines, thereby increasing the freedom of system configuration. The purpose is to increase the.

[Means for solving problems]

A plurality of connection terminals for connecting a plurality of telephone-type terminals each including a telephone capable of making and receiving calls automatically or manually and at least one non-telephone-type terminal, and a terminal that controls an interface with these plurality of terminals. an interface section, one contact Vt terminal connected to the telephone line-line;
It consists of another interface section that controls the interface with the telephone line network via this connection terminal, a modulation/demodulation section that modulates and demodulates data exchanged between non-telephone type terminals, and a control section that controls each of these sections. A line interface device will be provided.

[Effect]

The number of terminals is increased by sequentially cascading (cascading) telephone terminals including the line interface device to the telephone terminal connection terminal via telephone lines.

〔Example〕

FIG. 1 is a block diagram for explaining the terminal addition system according to the present invention, and FIG. 2 is a block diagram showing a specific example of the line interface device shown in FIG. 1.

First, explanation will be given from FIG. 2.

The line interface device 2 is a control circuit (CPU) 21
, scratch reversal detection circuit 22a, ringing signal (IR) detection circuit 22b, busy tone (BT), dial tone (DT)
Detection circuit 22c, terminal selection signal reception circuit 22d, loop closing circuit 22e, ring tone (RBT) transmission circuit 22f, guidance transmission path 22g, dial signal transmission circuit 22h
, calling signal sending circuit 221, signal route switching circuit 22j,
It is composed of a timer length selector switch 22k, a timer 22N, a relay control circuit 22rn, a call/response detection circuit 23, a boat connection switch 24, a modem circuit (MODEM) 25, etc., and the connection terminal (baud 1-) T2 is telephone,
A facsimile (FAX), a sketch phone, etc. are connected with an interface specification using a telephone line, and a terminal T
3 is connected to a personal computer or the like using, for example, an R3-232C interface specification. In Fig. 2, ■ is an exchange, 11 to β3 are telephone lines, and Tl is a connection terminal (boat).
, 3b is an external telephone, and 5b is an external data terminal.

Here, we will explain the procedure when, for example, there is an incoming call from the other party's telephone 3b to the line interface device 2.

When a call is received from the other party's telephone 3b, a ring tone (RBT) is sent from the telephone exchange 1 to the other party, and the telephone 'h'A
When a ringing signal (Ire) is sent to 1 +,
Line 1. The polarity of is reversed (one side (L,) of the two-wire system is earth and the other (L2) is -48V, L is -48V and L
2 changes into earth energy. ). When the line interface device 2 detects this reversal, the CPU 21 controls the loop closing circuit 2.
2e is activated and first makes a tentative response. When a selection signal for selecting a telephone terminal or a non-telephone terminal is sent after the provisional response of the line interface device 2, the terminal selection signal receiving circuit 22d receives this signal and then calls the corresponding terminal. Do the following. At this time, while sending the RBT created by the line interface device 2 to the calling side telephone 3b,
Telephone i3a housed in line interface device 2
, the IR is sent out by driving the calling signal sending circuit 22i, and the calling is performed. Thereafter, when the call/response detection circuit 23a detects a DC loop and detects a response from the telephone 3a, the calling signal sending circuit 221 and the ringing tone sending circuit 22f are restored and the IR is activated.

The RBT is stopped, the relay control circuit 22m is activated, and the boat connection switch 24a is operated from the bottom to the top in the diagram to connect the line II and the two-wire communication terminal connection terminal T2 to enable a telephone conversation.

Next, an explanation will be given of the operation when the data terminal 5a is specified by the calling side after the line interface device makes a provisional response.

In this case, the steps up to the provisional response are the same as those described above, so a description thereof will be omitted.

When the line interface device 2 tentatively responds, the CPU 21
Sends a calling signal consisting of a character code to any signal line of the multi-wire communication terminal connection terminal T3 via the signal route switching circuit 22j, or changes the voltage level of the signal line assigned for displaying an incoming call. As a result, the data terminal 5a is called, the ringing tone sending circuit 22f is activated, and the RBT is sent to the calling party.

A response signal consisting of a character code is returned from a signal line assigned to receive data from a data terminal housed in terminal T3, or a voltage level change of a signal line assigned for displaying a response occurs. ,CPU
21 detects a response from the terminal 5a via the No. 13 route switching circuit 22j, it restores the discharge sound output route 22f and stops the RBT, and then the signal route switching circuit 22j
, all of the signal lines of the terminal T3 used for communication with the transmitting side are connected to the modulation/demodulation circuit 25, thereby enabling communication with the transmitting side.

On the other hand, when there is a call request from the telephone 113a housed in the device 2, the CPU 21 sends a call/response detection circuit 23a to the call/response detection circuit 23a.
Detect this via . After that, the CPU 21 operates the relay control circuit 22m to connect the boat connection switch 2.
By switching the terminal 4a from the bottom to the top in the figure and connecting terminals T1 and T2, it is possible to make a call using the telephone 3a.

Note that when communication is being performed on a telephone type terminal or a data terminal at the time of making this call, the CPU 21 opens the loop using the loop closing circuit 220, disconnects the line, and restores it to its initial state. Make calls a priority.

Next, the operation when making a call from the data terminal 5a will be explained.

FIG. 3 is a chart for explaining the operation when making a call from the data terminal 5a via the terminal T3. Here, the terminal T3 may be of any type as long as it can interface with the modulation/demodulation circuit 25, but in this case, for example, an R3-232C interface may be used.
Then, use 5 wires: SD, RTS, DTR, CTS, and DSR. In addition, in Fig. 3, the direction from the terminal to the line interface device is up, and the opposite direction is down, and when the signal level is high, it is off, and 1]-
It is on when the level is reached.

Now, when the R'rS line is turned on in response to a call request from the data terminal 5a, the CPU 21 operates the loop closing circuit 22c to close the loop. Thereafter, when the BT-DT detection circuit 22 (4') detects a dial tone (DT) from the subscriber line exchange 1, the CPU 21 turns on the CTS line and notifies the terminal 5a that the DT has been received.Data terminal 5a detects that the CTS line is turned on.
CP the telephone number of the other party's data terminal 5b via the SD line.
The signal is sent to U21, and the RTS line is turned off when the sending is completed. The CPU 21 detects the completion of dialing from the data terminal 5a by turning off the RTS line, and turns off the CTS line. The data terminal 5a confirms that the CPU 21 has received the dial signal by turning off the CTS line, and turns on the DTR line as a dial transmission request. When the CPU 2t detects that the DTR line is turned on, it activates the dial signal sending circuit 22kl and transmits the telephone number of the other party's data terminal 5b received from the data terminal 5a to the telephone line 6. Send to. Exchange 1 uses RBT for line II and the other party's line L.

After that, when the other data terminal responds, the exchange 1 stops sending RBT and IR. At this time, the polarity of the line 11 is reversed, so when the polarity reversal detection circuit 22a detects this, the CPU 21
When the R line is turned on and the data terminal 5a accommodated in the line interface device 2 is notified that the data terminal 5b on the other side has responded, the signal route switching circuit 22j
is operated to connect all the signal lines of the multi-wire communication terminal connection terminal T3 used for communication with the data terminal 5b of the other party to the modulation/demodulation circuit 25. This enables communication between the data terminal 5a and the other party's data terminal 5b.

Now, returning to FIG. 1, the terminal expansion method according to the present invention will be explained. In such a case, conventionally it was necessary to add a telephone line, but in this invention, as shown in FIG.
By connecting the line interface device 2S on the slave side with L, the number of terminals can be easily expanded. In other words, the expansion telephone line TL and the line interface device 2S on the slave side can be considered as one telephone type terminal for that on the mask side, and this relationship is based on the telephone type terminal of the line interface device 2S on the slave side. The same applies to the case where another line interface device is connected to the telephone line, so that the number of terminals can be increased without increasing the number of telephone lines. Note that although the control programs of the control circuits of the line interface device are slightly different between the mask side and the slave side, everything else can be realized with the same hardware configuration, making it easy and economical to expand the terminal. In addition, two control programs for the control circuit are prepared, one for the mask and one for the slave, and these can be selected using a switch, etc. (This allows the line interface device to be used for the mask and for the slave. They can be exactly the same.

With such a connection configuration, for example, when the telephone on the slave side makes a call, the telephone off-hook--loop detection circuit 23a on the slave side detects a loop.An extension telephone line TL is connected to port 1-T2 on the slave side. The telephone on the slave side can be connected to the exchange a1 and a call can be made by following the following steps: - Detecting a loop on the master side - Connecting the line β1 on the master side to the port T21 on the mask side.

In addition, in the case of an incoming call, the mask side device 2M temporarily responds, waits for a boat selection signal from the calling side, and waits for a boat selection signal from the calling side.
When receiving the selection signal, the mask side device 2M makes a telephone call to the slave side device 2S. At this time, the calling signal sending circuit 22i inside the mask side device operates. As a result, the slave side device 2S makes a provisional response, and after that, Q! at a predetermined timing! If you make it so that 8-way boat selection No. 48 is sent from the calling side,
This signal passes through the mask side device 2M to the slave side device 2S.
By decoding this, the desired terminal port can be selected and connected.

In the above description, the line interface devices are connected in cascade, but it goes without saying that the number of telephone terminals can be increased by connecting other telephone type terminals to the line interface device.

〔Effect of the invention〕

According to the invention, a connection terminal for connecting a telephone type terminal is provided, and a telephone line is expanded by sequentially cascading the telephone type terminals including a line interface device through the connection terminal by a telephone line. This provides the advantage that terminals can be easily added without having to do anything, and services can be provided with a greater degree of freedom in system configuration.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a configuration diagram showing a specific example of the line interface device shown in FIG. 1, and FIG. 3 is for explaining the transmission operation from a data terminal. FIG. 4 is a schematic diagram showing a conventional example of a data terminal accommodating system, and FIG. 5 is a schematic diagram showing another conventional example of a data terminal accommodating system. Description of symbols 1... Exchange, 2.2M, 2S... Line interface device accommodating multiple terminals, 3a to 3C... Telephone, 4
... Telephone type terminal, 5a to 5C ... Data terminal (DT
l? ), 7... converter, 21... control circuit (CP
U), 22...Network control unit (NCU), 22 a
...Polarity reversal detection circuit, 22b...Call signal HR)
Detection circuit, 22c... Busy tone (BT) - Dial tone (DT) detection circuit, 22d... Terminal selection signal receiving circuit, 22e... Loop closing circuit, 22f... Ringing tone (RB T) ) Sending circuit, 22g... Guidance sending circuit, 22h... Dial signal sending circuit, 22i.
...Call signal sending circuit, 22j...Signal route switching circuit, 22k...Timer length selection switch, 221...Timer, 22m...Relay control circuit, 23 (23a-2
3d)...Call/response detection circuit, 24 (24a to 24
d)... Port connection switch, 25... Modulation/demodulation circuit (MODEM), l, ~7!4... Telephone line, Tl,
T2. T21. T3, T5... Connection terminal (boat),
TL: Telephone line for equipment expansion. Agent Patent Attorney Akio Namiki Agent Patent Attorney Kiyoo Matsuzaki 1v! J Figure 3 Procedural Amendment 61 N +3 1920, Month, Day, Commissioner of the Patent Office, Black 1) Ming Dat, Mr. 1, Indication of the case, 1986 Patent Application No. 70599, 2, Name of the invention, Line interface device accommodating multiple terminals Terminal expansion method 3, relationship with the amended case Patent applicant address 1-1-6 Uchisaiwai-cho, Chiyoda-ku, Tokyo Name
(422) Nippon Telegraph and Telephone Corporation Address: Namiki Patent Office 5, 5th floor, Fujita Building, 2-12-8 Shin-4i, Minato-ku, Tokyo Date of amendment order Voluntary action 7 Contents of amendment 1) Full text of the specification attached. Correct accordingly. 2) Correct Figures 4 and 5 as shown in the attached sheet. Full text correction Specification 1, Name of the invention, Terminal expansion method 2 in a line interface device accommodating multiple terminals, Claims: A method for adding multiple terminals in a line interface device accommodating multiple terminals, comprising a plurality of connection terminals for accommodating a plurality of telephones and non-telephone terminals, - for a subscriber line. In a line interface device accommodating multiple terminals that is connected and capable of selective communication with external telephones or non-telephone terminals, the telephone terminal including the device is cascade-connected to the connection terminal via a telephone line. 1. A method for adding terminals in a line interface device accommodating multiple terminals, characterized in that the number of terminals can be added by adding more terminals. 3. Detailed Description of the Invention [Field of Industrial Application] This invention provides: - In addition to a telephone, a subscriber line can be connected to a facsimile communication terminal, an image communication terminal, and a non-ringing communication terminal (hereinafter collectively referred to as telephone type terminals). ), a data terminal such as a personal computer (also referred to as a non-telephone type terminal), etc., and is capable of selectively connecting to other external terminals (hereinafter referred to as a multi-terminal line interface device). (also referred to as a line interface device), particularly relates to a method for adding terminals to such a line interface device. [Prior art] A telephone terminal device or a data terminal device (simply,
Also abbreviated as DTE. ) is shown in FIG. 4, for example. Note that FIG. 4 is an example of a DTE. In the figure, 1 is a telephone exchange, 3C is a telephone, 5C is a DTE, 6 is a converter, 22 is a network control unit (NCU), and 25 is a modulation/demodulation unit (
MODEM), f4 is a subscriber line. This is a method in which the DTE is installed as a "telephone connection device" using a converter 6 as shown in the figure. Here, converter 6 connects subscriber line 7!4. It is connected to the telephone set 3C and the data terminal 5C, and serves to connect the subscriber line 14 to the telephone set 3C or to the terminal 5C by manual operation of the converter 6. In addition, D
A terminal other than the TE, such as a facsimile terminal, is connected to the converter 6 in the same way as the telephone 3C. However, since this method relies on manual operation of the converter 6, it is difficult to communicate between "telephone calls" and "non-telephone communications."
becomes semi-fixed, causing various inconveniences. For this reason, recently, for example, for DTE, a modem-equipped telephone a (with a built-in network control unit R (NCU)) has appeared. FIG. 5 is a schematic diagram showing a telephone with a modem. Note that each symbol indicated by \ is the same as in Fig. 4, and T
4 is a multi-wire communication terminal connection terminal (also referred to as a port). That is, this telephone with a modem has a port (multiline communication terminal connection terminal T4) that accommodates the DTE, and the DTE terminal 5
This facilitates the connection of C. Here, in order to automatically switch between the telephone a3c and the terminal 5c, the NCU 22 is equipped with this function.
We are ensuring that "phone calls" and "communications" do not become semi-fixed. [Problem to be solved by the invention] However, the number of terminals that can be installed in such a modem-equipped telephone is limited by cost and manufacturing constraints. It is necessary to install additional telephones with modems. In other words, each time an additional telephone line is installed, additional telephone lines must be added, resulting in a problem of extremely high costs. Therefore, the present invention enables telephone calls and communications other than telephones to be made semi-fixed, and also facilitates expansion or expansion of the number of boats without adding any subscriber lines. The purpose is to increase the degree of freedom in configuration. [Means for solving the problem] The system is equipped with a plurality of connection terminals for accommodating a plurality of telephones and non-telephone terminals, and is connected to the subscriber line to enable selective communication with external telephones or non-telephone terminals. In a line interface device capable of accommodating multiple terminals, the number of terminals can be increased by 1) cascading a telephone type terminal device including this line interface device to the connection terminal No. 11 via a telephone line. [Function] By doing as described above, it is possible to increase the number of telephone terminal devices including line interface devices, thereby increasing the degree of freedom in system configuration and improving services. [Embodiment] FIG. 1 is a block diagram for explaining a terminal addition system according to the present invention, and FIG. 2 is a configuration diagram showing a specific example of the line interface device shown in FIG. 1. First, explanation will be given starting from FIG. The line interface device 2 is a control circuit (CPU) 21
, polarity reversal detection circuit 22a, ringing signal (IR) detection circuit 22b, busy tone (BT), dial tone (DT)
Detection circuit 22c, terminal selection signal receiving circuit 22d, loop closing circuit 22e, ring tone (RBT) sending circuit 22f, guidance sending circuit 22g, dial signal sending circuit 22h
, calling signal sending circuit 221, signal route switching circuit 22j,
It is composed of a timer length changeover switch 22, a timer 221, a relay control circuit 22m, a call/response detection circuit 23, a boat connection switch 24, a modem circuit (MODEM) 25, etc. 1 is an exchange, 11-I! , is the subscriber line, T
I and T2 are two-wire communication terminal connection terminals, T3 is a multi-wire communication terminal connection terminal (boat), 3b is an external telephone, and 5b is an external data terminal. Here, a procedure will be described when, for example, there is an incoming call from the other party's telephone i3b to the line interface device 2. When a call is received from the telephone 3b of the other party, a ring tone (RBT) is sent from the telephone exchange 1 to the other party, and a discharge signal (IR) is sent to the subscriber line II.
The polarity of is reversed (one (Ll) of the two-wire system is earth air and the other (L2) is -48V, so L2 is earth air and Ll is -48V
Changes to ). When line interface device 2 detects this reversal, C
The PU 21 first makes a tentative response by operating the loop closing circuit 22e. When a selection signal for selecting a telephone terminal or a non-telephone terminal is sent after the provisional response of the line interface device 2, the terminal selection signal receiving circuit 22d receives this signal and then calls the corresponding terminal. Do the following. here,
First, the operation when the telephone 3a is designated by the calling party will be explained. At this time, the RBT created by the line interface device 2 is sent to the calling side telephone 3b, while the calling signal sending circuit 221 is driven to the telephone 3a housed in the line interface device 2. This causes the IR to be sent and the call to be made. After that, when the call/response detection circuit 23a detects a DC loop and detects a response from the telephone 3a, the ringing signal sending circuit 22i and the ringing tone sending circuit 22f are restored, IR and RBT are stopped, and the relay control circuit 22m and operate the boat connection switch 24a from the bottom of the figure to the top, connecting subscriber lines l and 2.
The line communication terminal connection terminal T2 is connected to enable communication. Next, an explanation will be given of the operation when the data terminal 5a is specified by the calling side after the line interface device makes a provisional response. In this case, the steps up to the provisional response are the same as those described above, so a description thereof will be omitted. When the line interface device 2 tentatively responds, the CPU 21
Sends a calling signal consisting of a character code to any signal line of the multi-wire communication terminal connection terminal T3 via the signal route switching circuit 22j, or changes the voltage level of the signal line assigned for displaying an incoming call. As a result, the data terminal 5a is called, the ringing tone sending circuit 22f is activated, and the RBT is sent to the calling party. Among the multi-wire communication terminal connection terminals T3, a signal line allocated for receiving data from a data terminal accommodated therein returns a response signal consisting of a character code, or a signal line allocated for displaying a response. When the CPU 21 detects a response from the terminal 5a via the signal route switching circuit 22j due to a voltage level change, the ringing tone sending circuit 22
When f is restored and RBT is stopped, the signal route switching circuit 22j is activated, and all the signal lines used for communication with the transmitting side among the signal lines of the multi-wire communication terminal connection terminal T3 are switched to the modem circuit. 25 to enable communication with the calling party. On the other hand, when there is a call request from the telephone 3a housed in the device 2, the CPU 21 detects this via the call/response detection circuit 23a. After that, the CPU 21 operates the relay control circuit 22m to connect the boat connection switch 24a.
By switching from the bottom to the top of the diagram and connecting the two-wire communication terminal connection terminals T1 and T2, it is possible to make a call using the telephone 3a. Note that when communication is being performed on a telephone type terminal or a data terminal at the time of making this call, the CPU 2t opens the loop using the loop closing circuit 22e, disconnects the line, and restores it to its initial state. , to prioritize calls. Next, the operation when making a call from the data terminal 5a will be explained. FIG. 3 is a time chart 1 for explaining the operation when a call is made from the data terminal 5a via the multi-wire communication terminal connection terminal T3. Here, multi-wire communication terminal connection terminal T
3 may be any device that can interface with the modulation/demodulation circuit 25, but in this case, for example, R3-2
32C interface, SD, RTS
, D.T.R. Use CTS and DSR 5 wires. Further, in FIG. 3, the direction from the terminal to the line interface device is up, and the opposite direction is down, and the signal level is off when it is high and on when it is low. Now, when the RTS line is turned on in response to a call request from the data terminal 5a, the CPU 21 operates the loop closing circuit 22e to close the loop. After that, subscriber line exchange [1
The dial tone (DT) from the BT-DT detection circuit 2
2c, the CPU 21 turns on the CTS line,
The terminal 5a is notified that the DT has been received. When the data terminal 5a detects that the CTS line is turned on, the SD
The telephone number of the other party's data terminal 5b is sent to the CPU via the line.
21, and when the sending ends, I'? Turn off the TS line. The CPU 21 disconnects from the data terminal 5 by turning off the RTS line.
Detects the end of dialing from a and turns off the CTS line. The data terminal 5a is connected to the CPU 21 by turning off the CTS line.
confirms that it has received the dial signal and turns on the DTR line as a dial transmission request. CPU21 is DTR
When it detects that the line is on, it activates the dial signal sending circuit 22h and sends the telephone number of the other party's data terminal 5b received from the data terminal 5a to the subscriber's line! , to be sent. Exchange l connects subscriber line 2. and fR to the subscriber line 12 of the other party, and then, when the data terminal of the other party responds, the exchange 1 stops sending RIOT and tR. At this time, subscriber line l. Since the polarity of is reversed, when this is detected by the polarity reversal detection circuit 22a, the CPU 21 outputs D]? When the line is turned on and the data terminal 5a housed in the line interface device 2 is notified that the other party's data terminal 5b has responded, the signal route switching circuit 22j is activated and multiple Among the signal lines of the line communication terminal connection terminal T3, all lines used for communication with the other party's data terminal 5b are connected to the modulation/demodulation circuit 25.
Connect to. This enables communication between the data terminal 5a and the other party's data terminal 5b. Now, returning to FIG. 1, the terminal expansion method according to the present invention will be explained. In such a case, conventionally it was necessary to add additional subscriber lines, but in the present invention, as shown in FIG.
By connecting the line interface device 2S on the slave side with L, the number of terminals can be easily expanded. In other words, the expansion telephone line TL and the line interface device 2S on the slave side can be regarded as one telephone terminal for the mask side, and this relationship is 2k' of the line interface device 2S on the slave side. j1
The same applies to the case where another line interface device is connected to the communication terminal connection terminal, so that it is possible to increase the number of terminals using only telephone lines without increasing the number of subscriber lines. Note that although the control programs for the control circuits of the line interface device differ slightly between the mask side and the slave side, everything else can be realized with the same hardware configuration, making it easy and economical to expand the terminal. Also,
By preparing two control programs for the control circuit, one for the mask and one for the slave, and allowing them to be selected using a switch, etc., it is possible to use exactly the same line interface device for the mask and slave. It can be done. With such a connection configuration, for example, when the telephone on the slave side makes a call, the telephone goes off-hook - the loop detection circuit 23a on the slave side detects a loop - the extension telephone line TL is connected to the boat T2 on the slave side - the master side It is possible to connect the telephone on the slave side to the exchange 1 and make a call by following the procedure of detecting a loop by connecting the subscriber line 11 on the master side to the boat T21 on the mask side. In addition, in the case of an incoming call, the mask side device 2M temporarily responds and waits for a boat selection signal from the calling side, and when the selection signal of port 1-T21 is received, the mask side device 2M responds to the slave side device 2s. to make a phone call. At this time, the calling signal sending circuit 22i inside the mask side device operates. As a result, the slave side device 2S temporarily responds,
After that, if the final boat selection signal is sent from the calling side at a predetermined timing, this signal will directly reach the slave side device 2S via the mask side device 2M, so it can be decoded. The desired terminal boat can be selected and connected. In addition, in the above, the line interface devices are
It goes without saying that the number of telephone terminals can be increased by connecting other telephone terminals to the line interface device. Moreover, although the case where the line interface device accommodates a telephone, a telephone type terminal, and a data terminal (non-telephone type terminal) has been described above, in some cases, a non-telephone type terminal may not be provided. In such a case, it goes without saying that the signal route switching circuit 22j, timer length switching switch 22k, modulation/demodulation circuit 25, etc. shown in FIG. 1 can be omitted. [Effects of the Invention] According to the present invention, a connection terminal for connecting a telephone type terminal is provided, and a telephone is connected via the connection terminal. By sequentially cascading telephone terminals including telephone terminals and line interface devices via telephone lines, it is possible to easily add various terminals without adding subscriber lines, and the system configuration can be improved. This provides the advantage of being able to provide services with a greater degree of freedom. 4. Brief description of the drawings Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a block diagram showing a specific example of the line interface device shown in Fig. 1, and Fig. 3 is a block diagram showing a specific example of the line interface device shown in Fig. 1. FIG. 4 is a schematic diagram showing a conventional example of a data terminal accommodating system, and FIG. 5 is a schematic diagram showing another conventional example of a data terminal accommodating system. Description of symbols 1...Switchboard, 2.2M, 2S...Line interface device accommodating multiple terminals, 3a to 3c...Telephone, 4
...Telephone type terminal, 5a-5c...Data terminal (DT
E), 6... converter, 21... control circuit (CPU)
, 22... Network control unit (NCU), 22a... Polarity reversal detection circuit, 22b... Ringing signal (IR) detection circuit, 22c... Busy tone (BT)/dial tone (D
T) Detection circuit, 22d...Terminal selection signal receiving circuit, 2
2e...Loop closing circuit, 22f...Ring tone (RB
T) Sending circuit, 22g... Guidance sending circuit, 2
2h...Dial signal sending circuit, 22i...Calling signal sending circuit, 22j...Signal route switching circuit, 22k...
...Timer length selection switch, 22β...Timer, 22
m...Relay control circuit, 23 (23a to 23d)...
・Call/response detection circuit, 24 (24, a to 24 d)...
・Boat connection switch, 25...modulation/demodulation circuit (MOD
EM), l, ~I! 4...Subscriber line, T1...Subscriber line connection terminal, T2...2-wire communication terminal connection terminal, T3
．． T4...Multi-wire communication terminal connection terminal, T21...Connection terminal (boat), TL...Telephone line for device expansion. Agent Patent Attorney Akio Namiki Agent Patent Attorney Kiyoshi Matsuzaki $S Engineering Figure 4

Claims (1)

[Scope of Claims] A plurality of connection terminals for connecting each of a plurality of telephone type terminals including a telephone and a silent communication terminal each capable of automatically or manually making and receiving calls and at least one non-telephone type terminal; A terminal interface unit that controls the interface with the telephone terminal and the non-telephone terminal, one connection terminal connected to a single telephone line, and an interface with the telephone line network via the connection terminal. A terminal in a line interface device accommodating multiple terminals, comprising: another interface section that controls the communication between non-telephone type terminals; a modem section that modulates and demodulates data exchanged between non-telephone terminals; and a control section that controls each of the sections. A line interface accommodating multiple terminals, characterized in that the number of terminals is increased by successively cascading a telephone terminal including the device to the telephone terminal connection terminal via a telephone line. A method for adding terminals to equipment.