JPH0732429B2 - Multiple terminal accommodating line interface device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a plurality of telephones, a facsimile communication terminal, a picture communication terminal, and a silent communication terminal in one telephone line (hereinafter, these are collectively referred to as a telephone type. Also called a terminal.)
And a data terminal (also referred to as a non-telephone type terminal) such as at least one personal computer and capable of selectively connecting to other external terminals (hereinafter, simply referred to as a line interface). It is also called a face device.)

[Conventional technology]

As a method for installing a data terminal device (simply abbreviated as DTE) on a telephone line, for example, the one shown in FIG. 7 is known. In the figure, 1 is a telephone exchange, 3C is a telephone, 5C is a DTE, 7 is a converter, 22 is a network control unit (NCU), 25 is a modem (MODEM), and l ₄ is a telephone line.

This is a method of installing the DTE as a "telephone connection device" by the converter 7 as shown in the figure. Here, converter 7
Telephone 3C the line l ₄ by the telephone line l _4, is connected to the telephone 3C and data terminals 5C, manual operation of the diverter 7
, Or to the terminal 5C.

However, since this method depends on the manual operation of the converter 7, the "phone call" and the "data communication" are semi-fixed, which causes various inconveniences. For this reason, modem hair telephones (with built-in network control unit (NCU)) have recently appeared.

FIG. 8 is a schematic diagram showing a telephone with a modem. Each reference numeral shown here is the same as in FIG. 7, and T5 is a connection terminal (also referred to as a port).

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

[Problems to be solved by the invention]

However, the number of terminals that can be provided in such a modem-equipped telephone set is limited by cost and manufacturing restrictions. Therefore, when a large number of ports are required, a similar modem-equipped telephone set must be added. In other words, since it is necessary to add a telephone line each time the number of expansions is increased, there is a problem that the cost becomes very high. Further, since there is no port for connecting a so-called no ringing DTE, which is a type that does not ring a ringing bell like a mini FAX or a telemeter terminal, there is a problem that these cannot be accommodated.

Therefore, the present invention enables telephone communication and data communication to be performed without being semi-fixed, enables the number of ports to be expanded without adding any telephone line, and can accommodate silent DTEs. The basic purpose is to provide various functions to back up such a configuration, and to enable effective telephone communication and data communication.

[Means for solving problems]

A plurality of telephone terminals, each of which is capable of making and receiving calls automatically or manually, and a plurality of connection terminals for respectively connecting at least one non-telephone type terminal and a telephone type terminal, and a plurality of these terminals. A terminal interface section that controls the interface, one connection terminal that is connected to one telephone line, another interface section that controls the telephone line network via this connection terminal, and a non-telephone type terminal. A modulation / demodulation unit that modulates / demodulates data exchanged between them and a control unit that controls these units are provided.

[Action]

When the above connection terminals can be used to connect various terminals including silent communication terminals, the main line interface devices will be sequentially connected in cascade to the connection terminals for telephone type terminals via extension telephone lines. By doing so, it is possible to appropriately add more. Then, based on the selection signal from the other terminal, each terminal accommodated in this interface device is selected, and while one of the telephone type terminals is communicating, a call origination request is made from another telephone type terminal. If there is, a call can be made from this other telephone type terminal while maintaining the already established communication path. By the way, if this method is used, the service for telephone subscribers who do not know such a device may be deteriorated. Therefore, at least at the time of an incoming call, if the selection signal from the other terminal is not received within a certain period of time, the telephone communication is not performed. If priority is given and each terminal is selected if a selection signal from the other terminal is received, a timer is activated each time the selection signal is received and time monitoring is performed, and if there is no response from the corresponding terminal within the predetermined time period, By notifying the caller of this fact and disconnecting the telephone line, improper charging will not be forced. Furthermore, when receiving an instruction to make an emergency call from a non-telephone type terminal during telephone communication, the telephone line is disconnected and then processing is performed to allow the non-telephone type terminal to make a call, while the non-telephone type terminal automatically sends the call. When a command for making a call is received, the connection process with the partner terminal indicated by the command is sequentially performed.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1 is a telephone exchange, 2 is a line interface device accommodating a plurality of terminals, 3a and 3b are telephones, 4 is a telephone type terminal, and 5a,
5b is data terminal, 6 is a headset, l ₁ to l ₃ telephone lines, T1, T2 (T2a~T2d), the T3 and T4 is a connection terminal (port). The line interface device 2 includes a control circuit (CPU) 21, a polarity reversal detection circuit 22a, a ringing signal (IR) detection circuit 22b, a busy tone (BT) / dial tone (DT) detection circuit.
22c, terminal selection signal receiving circuit 22d, loop closing circuit 22e, ringing tone (RBT) sending circuit 22f, guidance sending circuit 22g, dial signal sending circuit 22h, calling signal sending circuit 22i, signal route switching circuit 22j, timer length Changeover switch 22k, timer 22l, relay control circuit 22m, call / response detection circuit 23, port connection switch 2
It is composed of a modem circuit (MODEM) 25, relays 26 and 27, and the like.

First, the procedure when there is an incoming call from the partner telephone 3b to the line interface device 2 will be described.

When an incoming call is received from the other party's telephone 3b, a ringing tone (RBT) is sent from the telephone exchange 1 to the other party, and a ringing signal (IR) is sent to the telephone line l ₁ , so that the line 1 ₁ The polarity is reversed (one of the two-wire system (L ₁ ) changes to ground and the other (L ₂ ) changes from −48V, L ₁ changes to −48V and L ₂ changes to ground). When the line interface device 2 detects this inversion, the CPU 21 operates the loop closing circuit 22e and first makes a temporary response. After the provisional response of the line interface device 2, when a selection signal for selecting a telephone type terminal or a non-telephone type terminal is sent, the terminal selection signal receiving circuit 22d receives this and then calls the corresponding terminal. Do. At this time, while transmitting the RBT created by the line interface device 2 to the calling side telephone 3b, the telephone housed in the line interface device 2
For 3a, the calling signal sending circuit 22i is driven to send IR to call. After that, when the calling / answer detecting circuit 23a detects a DC loop and detects a response from the telephone 3a, the calling signal sending circuit 22i and the calling sound sending circuit 22f are restored to stop the IR and RBT, and the relay control circuit. 22m is activated and the port connection switch 24a is operated from the bottom to the top of the figure to connect the line ₁₁ and the two-wire communication terminal connection terminal T2 to enable a call.

Next, the operation when the data terminal 5a is designated by the calling side after the temporary response of the line interface device will be described. In this case, the procedure up to the provisional response is the same as that described above, and therefore its description is omitted.

When the line interface device 2 makes a temporary response, the multi-line communication terminal connection terminal T3 is sent from the CPU 21 via the signal route switching circuit 22j.
By sending a ringing signal consisting of a character code to one of the signal lines of the above, or by changing the voltage level of the signal line assigned for incoming call display, the data terminal
While calling 5a, it activates the ringing tone sending circuit 22f and sends RBT to the calling side. Of terminal T3,
When the response signal consisting of a character code is returned from the signal line assigned for receiving data from the data terminal accommodated in it, or the voltage level of the signal line assigned for response display changes, the CPU 21 will switch the signal route. Switching circuit 2
When the response from the terminal 5a is detected via 2j, the ring back tone sending circuit 22f is restored and the RBT is stopped, and the signal route switching circuit 22j is operated to connect the terminal T3 with the sending side. All signal lines used for the communication of are connected to the modulation / demodulation circuit 25 to enable communication with the transmitting side.

By using such a line interface device, as compared with the case where a data terminal is connected through a converter as a "telephone connection device" as in the conventional example shown in FIG. 7,
Telephone communication and data communication will not be semi-fixed,
Further, it is possible to solve the problem that only a single data terminal can be accommodated in a single telephone line like the telephone with a modem shown in FIG.

However, as described above, unless the telephone type terminal or the data terminal accommodated in the called-side line interface device responds, the calling side and the called-side line interface device are connected through the exchange 1. It will occasionally happen, and this will force unfair billing. In order to prevent such an inconvenience, when the receiving side line interface device makes a temporary response and then receives a selection signal for selecting a telephone type terminal or a data terminal from the calling side, the corresponding terminal is called and at the same time the terminal is called. A timer 22l for determining the unresponsiveness is started. This timer length (time) is automatically switched depending on whether the calling terminal is a telephone type or a non-telephone type. For example, when the calling terminal is a data terminal, it is possible to send back a response after this terminal detects a call from the called line interface device, when it is used offline, or when other operations are performed. When a call from the line interface device on the receiving side is detected and the operating program is stopped and a predetermined communication program is started again before returning a response, the timer length (time) To switch. In this case, change the timer length by changing the timer length switch.
The CPU 21 refers to the timer length changeover switch 22k when calling the data terminal, and sets the timer length according to the manual operation by the user. When a response is received from the terminal within the set timer time after the start of calling the terminal, the CPU 21 restores the timer 22l, and then performs the above-described processing for transitioning to the data communication and telephone communication states.
On the other hand, even if the timer 22l notifies the CPU 21 that the set timer time has elapsed after the start of calling the terminal, but if there is no response from the terminal, the CPU 21
After restoring 2l, stop calling to the terminal, restore ringing tone sending circuit 22f to the calling side and stop RBT, then activate the guidance sending circuit 22g and the terminal becomes unresponsive It is notified to the caller by guidance. This guidance consists of a talkie and a PB signal (peeling sound). If the calling side is a human being, the talkie is used. If it is a data terminal, the PB signal is changed to the signal format on the terminal T3 so that the data terminal can confirm it. To do. After sending the guidance, the CPU 21 restores the guidance sending circuit 22g,
The loop closing circuit 22e is restored to disconnect the line. The series of control operations described above can be easily realized by the function of the CPU.

By the way, in the conventional add-on device that can accommodate a telephone-type terminal, the incoming call is determined by detecting the polarity reversal (levers) and 16Hz call signal, so it is possible to accommodate a non-ringing terminal such as a mini-fax. There wasn't.
This is because the ringing for the silent DTE is detected from the polarity reversal and the single tone within the voice band (300 Hz to 3400 Hz). In the line interface device according to the present invention, the terminal T2 is provided as shown in the figure so that the silent DTE can be accommodated, while the CPU 21 makes the second
The determination process as shown in the figure is performed. The second
The figure is a flowchart showing the terminal selection processing operation by the control circuit. In other words, CPU21 reverses polarity (Levers)
And IR, and if IR is not detected within a predetermined time after polarity reversal (see Fig. 2B), port connection switch 24b
Is closed and connected to the silent DTE via the loop detection circuit 23b. When the silent DTE responds to the ringing signal by the single tone in the voice band, the loop is closed and the communication path is formed. The NR switch shown in FIG. 2 is a switch that is turned on when the silent DTE is connected. After that, when the communication is completed and the calling / response detection circuit 23b detects the opening of the loop, the port connection switch 24b is opened. In this way, the line interface device 2 has no ringing DT.
By providing the E connection terminal and adding the above functions to the CPU 21, it is possible to connect the silent DTE.

Next, the case of adding terminals will be described. In such a case, conventionally, it was inevitably necessary to add a telephone line, but in the present invention, as shown in FIG. 3, the master side line interface device 2M is connected to the extension side telephone TL to the slave side line interface. By connecting with the device 2S, the number of terminals can be easily expanded. That is, the extension telephone line
The TL and slave side line interface device 2S can be regarded as one telephone type terminal to that of the master side, and this relationship is the slave side line interface device.
The same applies to the case where another line interface device is connected to the 2S telephone type terminal, which allows the addition of terminals without increasing the number of telephone lines. In addition,
The control program of the control circuit of the line interface device differs slightly between the master side and the slave side, but the other parts can be realized with the same hardware configuration, so that the terminal can be easily expanded and it is economical. Further, by making two control programs for the master circuit for the master and for the slave easy so that they can be selected by a switch or the like, the line interface device for the master and the slave are completely the same. Can be

Next, the operation when a call request is issued from a telephone type terminal including the telephone 3a during communication with the data terminal will be described.

When a call request is made, the CPU 21 firstly makes a call / response detection circuit 23.
This is detected by any of the above, and the loop closing circuit 22e is operated to open the loop and disconnect the line to restore it to the initial state. After that, the relay control circuit 22m is operated to switch one of the port connection switches 24 from the bottom to the top in the figure, and the terminals T1 and T2 are connected to each other, so that the telephone type terminal can communicate. That is, according to such a method, the telephone type terminal can be preferentially connected regardless of which data terminal of the line interface device 2 is in use.

On the other hand, when there is an incoming call to this line interface device, this device closes the loop and tentatively responds after detecting the polarity reversal and 16Hz ringing signal. When the selection signal for selecting the telephone type terminal or the data terminal is not sent, the control circuit 21 is operated so that the port connection switch 24a operates from the bottom to the top of the figure.
Works, and preferentially connects to the telephone 3a.

Further, the present invention provides any one of telephone type terminals including a telephone.
If a call request is made from another telephone type terminal while the communication is being performed, it is possible to make a call from the other telephone type terminal while maintaining the already established communication path. .

That is, for example, when a call is made using a telephone accommodated in the telephone type terminal port T2d and a call is requested from a facsimile (FAX) accommodated in the telephone type terminal port T2c, the CPU 21 issues a call. The call / answer detection circuit 23c detects this and activates the relay control circuit 2m, and the port connection switch 24c operates from the bottom to the top of the figure to close the loop, while the port connection switch 24d shows the top of the figure. To work from down. This breaks the telephone loop while connecting the fax machine to line l ₁ . That is,
It is possible to switch from port T2d to port T2c while maintaining the communication path. In addition, this is the port T2d
When a call request is made again from the telephone housed in the telephone, the telephone is switched to the telephone side again in the same procedure as described above, and the same switching is performed thereafter. As described above, since switching between the telephone type terminal ports can be easily realized, it becomes possible to sequentially switch communication media from the telephone to another telephone type terminal or from another telephone type terminal to the telephone. Incidentally, such a function may be called a port switching function.

In this way, the telephone type terminal can be preferentially connected to the non-telephone type terminal in the case of outgoing call, while the telephone set can be preferentially connected in the case of incoming call.

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

FIG. 4 is a time chart for explaining the operation in the case of transmitting 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 here, for example, RS
−232C interface is used, SD, RTS, DTR, C
Use 5 lines of TS and DSR. Also, in FIG. 4, the direction from the terminal to the line interface device is up, and the opposite direction is down, and the signal level is off at high level and on at low level.

Now, when the RTS line is turned on by a call request from the data terminal 5a, the CPU 21 operates the loop closing circuit 22e to close the loop. After that, when the dial tone (DT) from the subscriber line exchange 1 is detected by the BT / DT detection circuit 22c, the CPU
21 turns on the CTS line and notifies the terminal 5a that the DT has been received. When the data terminal 5a detects that the CTS line is turned on, it sends the telephone number of the partner data terminal 5b to the CPU 21 via the SD line, and turns off the RTS line upon completion of sending.
The CPU 21 detects the end of dialing from the data terminal 5a by turning off the RTS line, and turns off the CTS line. Data terminal 5a is CTS
The CPU 21 confirms that the dial signal has been received by turning off the line, and turns on the DTR line as a dial transmission request. When the CPU 21 detects that the DTR line is turned on, it activates the dial signal transmission circuit 22h and transmits the telephone number of the partner data terminal 5b received from the data terminal 5a to the telephone line l ₁ . The exchange 1 sends RBT to the line l ₁ and 1R to the partner line l ₂ , and when the partner data terminal responds, the switch 1 stops sending RBT and IR. At this time line ₁
When the polarity inversion detection circuit 22a detects this, the CPU 21 turns on the DSR line, and the data terminal 5a accommodated in the line interface device 2 reports that the data terminal 5b on the other side responds. Then, the signal route switching circuit 22j is operated to connect all the lines used for communication with the partner data terminal 5b among the signal lines of the multi-wire communication terminal connection terminal T3 to the modulation / demodulation circuit 25. Let This enables communication between the data terminal 5a and the partner data terminal 5b.

FIG. 5 is a time chart for explaining the operation when making an emergency call from the data terminal. The multi-wire communication terminal connection terminal T3 is an example of an RS-232C interface as in FIG.

In this case, the data terminal performs the operation of turning on the RTS line and the DTS line at the same time as shown in the figure, so that the CPU 21 detects the emergency call. At this time, if the telephone type terminals 3a and 4 are in use, the line l ₁ is disconnected, and after waiting for the line to be restored to the initial state, the loop closing circuit 22e is operated to close the loop. Since the DTR line is turned on when a call is requested, dial transmission is performed immediately after detecting the RTS line off. Once you make an emergency call,
Since the call from 3a or the telephone type terminal 4 is completely ignored by the CPU 21 until the end of the communication, the emergency call from the data terminal is secured. As described above, since the emergency call from the data terminal 5a is performed only by turning on the RTS line and the DTR line at the same time, both the data terminal and the line interface device can perform the process for the emergency call quickly and reliably. You can

Further, according to the present invention, the following continuous transmission (sequential transmission,
Calling) function. This is to automatically make a call or a data communication one after another by giving the control information C in the format as shown in FIG. 6 from the data terminal 5a to the line interface device 2. In FIG. 6, C1 is a control command, C2 is a switching channel, and C3 is a partner number.

That is, when the control information C shown in FIG. 6 is sent from the data terminal 5a to the CPU 21 via the terminal T3 and the signal route switching circuit 22j, the CPU 21 switches the relay 27 to the dial D side and makes a call through the line l _1. When the DT from the converter 1 is detected, the dial information C3 designated by the control information C is sent to the exchange 1. When the transmission of the dial information C3 is completed, the relay 27 is switched to the calling side S, and the relay 26 is switched according to the channel information C2 of the control information C. For example, if a call is instructed, the relay 26 is switched to the T side, and if data communication is instructed, it is switched to the P side. When the call or the data communication is completed, the disconnection is instructed by the control command C1, the line is disconnected and the initial state is returned to the next command reception waiting state. In this way, by providing the line interface device with such a function, it is possible to make a call with the headset 6 with the called party even after an automatic call, which cannot be realized by the telephone with a built-in modem which has been available in recent years. It will be possible. Also, since the line interface device is controlled so that the next automatic call can be made again after the end of the data communication or the call, the lines are automatically and sequentially connected according to the list of communication partners on the screen of the data terminal. You can connect and make calls and data communications. Therefore, such a call may be called a list call.

〔The invention's effect〕

According to the present invention, a plurality of telephone type terminals, non-telephone type terminals, and ringing-line non-ringing terminals can be provided on a single telephone line without requiring any modification on both telephone type terminals and non-telephone type terminals. It can be accommodated, and it is possible to make an outgoing call from any of them and receive an incoming call to any of them. In addition, it has a function to connect the telephone type terminal preferentially over the non-telephone type terminal when making an outgoing call, while it has the function to preferentially connect the telephone terminal when receiving an incoming call. Since it also has a priority function, call priority and emergency calls in an emergency can be secured. Furthermore, when the terminal does not respond, it has the function of notifying the caller side by the guidance and the function of disconnecting the line, so that improper charging can be minimized.

Further, according to the present invention, the ports accommodated in the device can be switched to the same party without disconnecting the line, and for example, from the telephone to the facsimile terminal or the facsimile terminal during the telephone communication. The communication media can be switched from to the telephone. Further, for example, an automatic call (list call) using a personal computer and a headset together is possible, and the time and effort required to make a collective call can be greatly saved. Further, according to the present invention, the accommodation terminal can be easily expanded only by connecting the present apparatus in cascade without adding a telephone line.

As described above, the line interface device according to the present invention is capable of accommodating a plurality of (three or more) terminals in a single telephone line, and is excellent in usability.
Since the telephone line can be effectively used, the economic effect is great, and the practical effect is also great.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing a terminal selection processing operation by a control circuit (CPU), FIG. 3 is a connection diagram for explaining an extended function according to the present invention, FIG. FIG. 4 is a time chart for explaining an operation when making a call from a data terminal, FIG. 5 is a time chart for explaining an emergency call operation from a data terminal, and FIG. 6 is a control for making an automatic call. FIG. 7 is a configuration diagram showing a signal format, FIG. 7 is a schematic diagram showing a conventional example of a data terminal accommodation system, and FIG. 8 is a schematic diagram showing another conventional example of a data terminal accommodation system. Explanation of symbols 1 …… Switchboard, 2,2M, 2S …… Multi-terminal accommodating line interface device, 3a to 3c …… Telephone, 4 …… Telephone type terminal,
5a-5c …… Data terminal (DTE), 6 …… Headset,
7-converter, 21-control circuit (CPU), 22-network controller (NCU), 22a-polarity reversal detection circuit, 22b-call signal (IR) detection circuit, 22c-busy tone (BT) / dial tone (DT) detection circuit, 22d …… Terminal selection signal reception circuit, 2
2e …… Loop closing circuit, 22f …… Ring tone (RBT) sending circuit, 22g …… Guidance sending circuit, 22h …… Dial signal sending circuit, 22i …… Calling signal sending circuit, 22j …… Signal route switching circuit , 22k …… Timer length selector switch, 22l …… Timer, 22m …… Relay control circuit, 23 (23a-23d) …… Calling / answer detection circuit, 24 (24a-24d) …… Port connection switch, 25… … Modulation / demodulation circuit (MODEM), 26,27 …… Relay, l ₁
~ L ₄ ...... Telephone line, T1 ~ T5 ...... Connection terminal (port), C
...... Control information, C1 ...... Control command, C2 ...... Switching channel, C3 ...... Other party number, TL ...... Device extension telephone line.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaaki Tanabe, 2356 Take, Yokosuka City, Kanagawa Pref., Information and Communication Processing Laboratory, Nippon Telegraph and Telephone Corporation (72) Inventor Tetsuro Yamashita 1 Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa No. 1 in Fuji Electric Co., Ltd. (72) Inventor Tatsuo Inoue 1 Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture No. 1 Fuji Electric Co., Ltd. (72) Takeshi Kamakura 1, Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture No. 1 within Fuji Electric Co., Ltd.

Claims (1)

[Claims] 1. A plurality of connection terminals for respectively connecting a plurality of telephone type terminals including a telephone and a silent communication terminal, each of which is capable of making and receiving calls automatically or manually, and a plurality of connection terminals for respectively connecting at least one non-telephone type terminal. A terminal interface section that respectively controls the interface with a telephone type terminal and a non-telephone type terminal, one connection terminal that is connected to one telephone line, and an interface with the telephone line network through the connection terminal. It includes another interface unit, a modulation / demodulation unit that modulates / demodulates data exchanged between non-telephone type terminals, and a control unit that controls each unit. A line interface device for accommodating a plurality of terminals, which is capable of sequentially cascade-connecting a terminal and the connection terminal for the telephone line of another device via an extension telephone line. If the terminal does not receive the selection signal from the partner terminal for selecting each terminal accommodated in the device after a temporary response after a certain time, the connection with the telephone is preferentially performed. When the selection signal is received, each terminal accommodated in the device is selected, and a timer is activated every time the selection signal is received to perform limit monitoring. If there is no response from the corresponding terminal within a predetermined time limit, the call is sent. To that effect, the telephone line is disconnected, and when making a call, the connection with the telephone type terminal is given priority over the connection with the non-telephone type terminal. When a call is requested from another telephone-type terminal during communication, the call can be made from the other telephone-type terminal while maintaining the already established communication path, while a non-phone call is made during telephone communication. When receiving an instruction to make an emergency call from a portable terminal Enables communication from the non-telephone type terminal after disconnecting the talk line, and when receiving a command for automatic transmission from the non-telephone type terminal, sequentially performs connection processing with the other terminal instructed by the command A multi-terminal accommodating line interface device characterized by the above.