KR100229027B1 - Telephone line interfacing circuit used for voice and non-voice terminals and method for controlling the same - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs

A technology relating to a line interface of a telephone communication system.

I. The technical problem that the invention is trying to solve

Provides a line interface circuit and its control method which unify the configuration without dualizing the dialer, the line interface unit and the DC masking circuit for the audio processing unit and the image processing unit for performing the emulsion mode and the power-on mode. Is in.

All. Summary of Solution of the Invention

In a line interface circuit which is shared between a voice terminal and a non-voice terminal connected to a switch via a telephone line, and operated by receiving a switch DC power, a single dialer and a communication port for communication with the non-voice terminal are provided. In the power-on state of the non-voice terminal for converting a predetermined AC power into a direct current, dial information received from the key matrix into the non-voice terminal is received through the communication port and transmitted to the dialer. In the power-off state of the voice terminal is characterized in that the line interface control unit for transmitting the dial information directly input from the key matrix to the dialer.

la. Important uses of the invention

Used to control line interfacing between voice and non-voice terminals.

Description

TELEPHONE LINE INTERFACING CIRCUIT USED FOR VOICE AND NON-VOICE TERMINALS AND METHOD FOR CONTROLLING THE SAME}

The present invention relates to a line interface circuit in a telephone communication system, and more particularly, to a line interface circuit and a method in which a voice terminal and a non-voice terminal can be shared without a redundant design.

The facsimile transmits and receives a still image through a telephone line. The facsimile can be classified into an image processing part and a voice processing part for making a voice call related to dialing and transmission and reception necessary for the facsimile transmission.

1 is a block diagram schematically showing the configuration of a conventional facsimile. The main control unit 101, hereinafter referred to as CPU _FAX 101, controls the overall operation of the fax transmission mode, reception mode, copy mode, and the like according to the set program. In addition, the CPU _FAX 101 may include a program memory and a data memory or may be externally connected as shown by reference numeral 109. A program for controlling the operation of the facsimile is stored in the program memory, and data generated during the execution of the program is temporarily stored in the data memory. The OPE 102 is composed of a key matrix, a display unit, and the like. The key matrix of the OPE 102 generates data of a key (for example, a numeric key for dialing) that the user presses to designate each mode and execute an operation of the designated mode, and outputs the data to the CPU _FAX 101. In addition, the display unit of the OPE 102 performs a function of inputting and displaying display data indicating an operation state of a system when performing each mode in the CPU _FAX 101. The sensor unit 103 detects the presence or absence of input of a document and the presence of print paper, and outputs the detected state signal to the CPU _FAX 101. The scanner 104 moves an input document, scans an image of the document, and converts the document into digital data. The image processing unit 105 performs processing such as distinguishing the image data input from the scanner 104 into the background and the text or generating halftone image data. It acts to make it possible to receive. The print unit 106 prints the image data input from the image processing unit 105 on the print paper under the control of the CPU _FAX 101 and performs the reception mode and the copy mode. The modem 107 is a non-voice terminal for performing data communication with the CPU _FAX 101 via a telephone line, which is essential for facsimile-specific operation. The modem 107 under the control of the control unit 101 modulates and transmits the image data output from the image processing unit 105 in a transmission mode in accordance with a transmission type, that is, a standard of a facsimile. The coded image signal input through the line is demodulated in its original form so that the modem 107 can process it. A line interface unit (LIU) 108 forms a transmission / reception path between a telephone line (tip, ring) and the modem 107 under the control of the controller 101. In other words, it performs an interface function between a telephone line and a modem, performs an interface function between a telephone line and a telephone, and performs a ring signal processing function and a dialing function received from an exchange.

FIG. 2 shows a detailed configuration of the LIU 108 in FIG. 1 together with its peripheral devices.

First, the interface function between the telephone line and the modem will be described.

When the facsimile data is communicated, the switch unit 110 in response to the switch control signal S1 output from the CPU _FAX 101 receives a signal input from a telephone line through a tip, ring (T, R) terminal. The first dialer 120 generating the dial pulse is connected to the modem 107 via the first line interface 130. In addition to the function of selecting such a non-voice path, the switch unit 110 passes through the second line interface unit 135 to the speech network 150 and the handset 180. It also selects the voice path and also the phone hook switch. The first dialer 120 interrupts the DC loop of the line by the dialer control signal S2 generated from the CPU _FAX 101 to generate a dial pulse, and forms a DC loop of the line during facsimile communication. Perform the function. The first line interface unit 130 is used to maintain AC impedance matching with the exchanger EXH, and includes primary / secondary separation function, AC signal coupling function, and DC masking function. Perform them. The signals generated from the modem 107 (modulated facsimile signals, DTMF dial signals, etc.) are transmitted to the telephone line.

Next, the interface function between the telephone line and the telephone is divided into the case where the power of the CPU _FAX 101 is turned on and the case where the power is turned off.

First, when the power of the CPU _FAX 101 is turned on, when a user lifts the handset 180, a hook detector (not shown) detects this and hooks the status to the CPU _FAX 101. Pass the signal. The CPU _FAX 101 receives the ?? off state signal and prepares to dial according to the key value input from the key matrix 250 in the modem 107 in the DTMF dial mode. In addition, in the dial pulse dial mode, the first dialer 120 is controlled to prepare for dialing. The speech network 150 has functions such as mutual conversion between voice signals and electrical signals, mutual conversion between 2-wire and 4-wire, AC impedance matching, side tone, DC masking, and handset. Do this.

When the power of the CPU _FAX 101 is turned off (no power operation or emergency mode), a separate hook switch is connected in parallel to the switch unit 110 so that the telephone line is connected to the speech network by mechanical movement of the handset 180. 150). At this time, it is possible to use a bridge diode in order to always supply a stable power irrespective of the power supply polarity change of the telephone line, which is a known fact.

Next, the dialing function will be described. The second dialer 170 for the dual tone multi-frequency (hereinafter referred to as DTMF) / dial pulse (hereinafter referred to as DP) is supplied with power from the speech network 150. It works. The second dialer 170 converts the dial information input from the key matrix 250 into a form corresponding to a dial mode (DTMF / DP) setting value and transmits the dial information to the speech network 150 to perform dialing. do.

As described above, the LIU is overlapped with two dialers 120 and 170, two line interface units 130 and 135, and a DC masking circuit. Many. Specifically, it has the following problems.

First, the problem with respect to the interface function between the telephone line and the modem and the telephone line and the telephone, as shown in Figure 2, the switch between the modem 107 and the speech network 150 through the switch unit 110 is Happens. Since AC impedance and DC masking circuit exist in each part, AC impedance and DCR (Direct Current Resistance) value of this part are different so that switching noise occurs in telephone line when telephone ↔ facsimile switching.

Second, the problem with the dialing function is described. Since the dialer 120 is also present in the modem path and the dialer 170 is present in the telephone path, a circuit for enabling a no-power operation can be designed. When the circuit characteristics of the two dialers (120, 170) should be designed to meet the communication standards.

Third, there is a problem in recognition of a confirmation tone during dialing in the power-on mode. In general, dial information is stored for use when performing functions such as LNR (Last Number Reidial) and ABR (Auto Busy Redial), and when dialing with handset 180 when CPU _FAX 101 is powered on, dialing The second dialer 170 cannot be used, and the DTMF dialer of the first dialer 120 or the modem 107 can be used. At this time, the telephone circuit is separated from the telephone line by the switch unit 110, and the speech network 150 cannot operate. Therefore, the user cannot confirm the dialing process through the handset 180, and feels inconvenience. That is, the switch unit 110 under the control of the CPU _FAX 101 connects the telephone line to the telephone only during the time after one digit is finished and before the next digit is generated. An abnormal operation occurs that the telephone handset is audible or not heard during a dial.

Fourth, there is a problem that the LNR is different in the emulsion mode. The last dial information while the main power is on is stored in the memory of the CPU _FAX 101, and the last dial information while the power is down is stored in the second dialer 170 on the telephone side. . Thus, LNR information stored in two locations may be different from each other. This can confuse the user and eventually lead to O'Daial.

Accordingly, an object of the present invention is to provide a line interface circuit that unifies the configuration of a dialer, a line interface unit, a DC masking circuit, and the like for an audio processing unit and an image processing unit to perform an emulsion mode and a power-on mode. And a control method thereof.

Another object of the present invention is to provide a line interface circuit and a method of controlling the same, which allow the user to always check his or her own dialing process.

It is still another object of the present invention to provide a line interface circuit that solves an opacity problem caused by confusion of a user in dualization by unifying the storage location of LNR information.

In order to achieve the above object, the present invention shares a voice terminal and a non-voice terminal interfaced with a switch through a telephone line, and in a line interface circuit operated by receiving a switch DC power, a single dialer and the non- A communication port for communication with a voice terminal and dial information input from the key matrix to the non-voice terminal in the power-on state of converting a predetermined AC power into direct current are used through the communication port. And a line interface control unit configured to receive and transmit the dialer information to the dialer in the power-off state of the non-voice terminal. In addition, the line interface portion of the voice terminal and the non-voice terminal is unified to be connected between the voice and non-voice pass switching unit and the telephone line.

1 is a block diagram schematically showing the configuration of a conventional facsimile

2 is a view showing a detailed configuration of a conventional facsimile line interface circuit together with its peripheral devices;

3 is a diagram illustrating a detailed configuration of a line interface circuit according to an exemplary embodiment of the present invention with its peripheral devices.

4 is an exemplary configuration diagram of a line current detection circuit that may be included in the line interface unit of FIG. 3.

5 is a first flowchart for line interfacing according to an embodiment of the present invention.

6 is a second flowchart for line interfacing according to an embodiment of the present invention.

7 is a diagram illustrating a protocol for transmitting and receiving commands and data between a control unit of a line interface circuit and a control unit of a facsimile in a power-on mode according to an exemplary embodiment of the present invention.

8 is a diagram illustrating a process of converting paths in a line interface circuit according to an embodiment of the present invention by receiving a command from a control unit of a facsimile machine;

9 is an exemplary message format transmitted from a control unit of a facsimile to a control unit of a line interface circuit according to an exemplary embodiment of the present invention.

10A and 10B illustrate an example of a message format transmitted from a controller of a line interface circuit to a controller of a facsimile according to an embodiment of the present invention.

FIG. 11 is a diagram illustrating a detailed configuration of a line interface circuit according to another exemplary embodiment of the present invention together with peripheral devices thereof. FIG.

Explanation of symbols for the main parts of the drawings

101: facsimile control unit (CPU _FAX ) 102: OPE

103: sensor unit 104: scanner

105: image processing unit 106: printing unit

107: modem 108: LIU

110: switch unit 180: handset

250: key matrix

320: control unit (CPU _LIU ) of the line interface circuit

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings. Also, in the following description, many specific details such as components of specific circuits are shown, which are provided to help a more general understanding of the present invention, and the present invention may be practiced without these specific details. It is self-evident to those of ordinary knowledge in Esau. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

3 shows a configuration of a LIU and its peripheral devices according to the present invention. Advantages The dashed line block 108 corresponds to the LIU, which uses the DC power supply of the exchanger, and the rest (modem, CPU _FAX ), etc., uses a DC conversion of AC 120 / 240V. The LIU may have a single chip form.

The LIU is equipped with a central processing unit or a digital logic having a similar function (which may include a central processing unit, hereinafter referred to as CPU _{LIU for} convenience). The CPU _LIU 320 transmits the CPU _FAX 101, necessary commands, and status information of the LIU (status, data between the LIU and the telephone line and changes thereof) through the communication port 340. Receiving can control line interfacing and telephony functions. UART (Universal Asynchronous Receiver Transmitter) may be used as the communication port.

In addition, the CPU _LIU 320 receives dial digit information from the CPU _FAX 101 through the communication port 340 in the LIU or dials the dial digit information directly input from the key matrix 250 to the dialer 360. To be dialed by a single dialer 360 inside the LIU, regardless of the main power on / off state. In addition, the dialing process is also transmitted to the voice path (VP) in the LIU 108 so that the user can check it in the dial.

On the other hand, when the user presses any key of the key matrix 250, a corresponding code value is transmitted to the dialer 360 or the CPU _FAX 101 of the LIU 108, and the designation of the forwarding destination is CPU _LIU 320 does. That is, the CPU _LIU 320 generates a key input enable signal so that the key code value is transmitted to the dialer 360 of the LIU 108 only in the emergency mode, and the CPU _FAX 101 in the power-on mode. Generates a key input disable signal so that the key code value is transmitted only at

In addition, the CPU _LIU 320 stores the dial information last dialed in the emergency mode, and then transfers the information to the CPU _FAX 101 through the communication port 340 in the power-on mode so that the LNR is not changed. Do not

Thus, some circuits (dialers and line interface units) are used in common by the audio processing unit and the image processing unit (telephone, facsimile) so that line noise due to telephone / facsimile switching does not occur.

FIG. 4 illustrates a configuration example of a line current detection circuit that may be provided in the line interface unit 370 of FIG. 3 and includes a plurality of resistors R1 to R4 and comparators COM1 to COM3. Values LCV1 to LCV3 output from the three comparators COM1 to COM3 are transferred to the CPU _LIU 320. For example, when the value is changed from '011' to '110', the value changes by several steps. You can check how many milliamps (mA) you have seen by changing the current.

When one terminal is holding the line and the parallel telephone occupies the line at the same time, the amount of current in the line is reduced. When the line interface unit 370 senses the current line current amount and transfers the current amount of line current to the CPU _LIU 320, the CPU _LIU 320 is hooked on / off or parallel dialed according to the degree of change. Detect the long line broken state of the and make a corresponding message and delivers it to the CPU _FAX 101 through the communication port (340). Therefore, by receiving the message, the CPU _FAX 101 can check whether the parallel telephone is on / off or a long line disconnected state during dialing.

On the other hand, if more resistors for providing a comparator and a reference value for the comparison are provided than in this embodiment, the sharpness of the detection can be increased.

5 and 6 are flow charts for line interfacing according to an embodiment of the present invention, respectively, which illustrate an initial operation procedure occurring between the LIU 108 and the CPU _FAX 101. In FIG. 6 is a case of emulsion mode.

7 is a diagram illustrating a protocol for transmitting and receiving commands and data between the CPU _LIU 320 and the CPU _FAX 101 according to an embodiment of the present invention, and FIG. 8 is a line interface circuit 108 according to an embodiment of the present invention. Is a diagram illustrating a process of converting the paths inside the module by receiving an instruction from the CPU _FAX 101.

9 is an exemplary message format transmitted from the CPU _FAX 101 to the CPU _LIU 320 according to an embodiment of the present invention, and has two types of data and instructions.

10A and 10B are diagrams illustrating a message format transmitted from the CPU _LIU 320 to the CPU _FAX 101 according to an embodiment of the present invention. FIG. 10A is a response message and FIG. 10B is a hook event message. . In the case of the response message, the lower five bits b0 to b4 are echoes of the last received data d1 to d5, and are shifted one bit to the right. In addition, the upper three bits (b7 to b5) in the two message formats are for indicating a hook on / off state for dial mode, manual or electronic hook switch. For example, in the case of dial mode, a b5 bit of 0 means dial pulse dialing, and 1 means tone dialing.

Based on the above configuration, the line interface operation according to the present invention will be described in detail.

Referring to FIG. 5, when the user hooks off the handset 180, the LIU 108 is powered on by the line current of the exchange. At this time, the CPU _LIU 320 of the LIU 108 checks whether the CPU _FAX 101 is powered on or off, whether the main power of the facsimile is on or off. There are various ways to check this. One way is that the CPU _LIU 320 sends a predetermined command to the CPU _FAX 101 using the communication port 340 and waits for a predetermined time for a response from the CPU _FAX 101. At this time, if there is a response from the CPU _FAX 101 within the period, it is recognized that the CPU _FAX 101 is in a power-on state, and otherwise, it is regarded as a power-off (emergency mode). Alternatively, there is a hardware port between the CPU _FAX 101 and the LIU 108 and the CPU _LIU 320 checks the state of the port to determine the power on / off of the CPU _FAX 101. You may. Alternatively, the CPU _FAX 101 periodically transmits a pre-appointed command via the communication 340 to the CPU _LIU 320 of the LIU 108 and then the CPU _LIU 320 for the instruction. the response sent to the _FAX CPU (101) at this moment is the method _FAX CPU (101) gives the instruction to cause the normal operation to the _LIU CPU (320).

In addition, the CPU _LIU 320 transmits the hook-off state signal to the CPU _FAX 101 through the communication port 340 and sets an internal timer at step 501. This is to check whether a predetermined response is received from the CPU _FAX 101 within a predetermined time as shown in step 502. If there is no response within the predetermined time from the CPU _FAX 101, the process proceeds to step 506 to check whether the timer has timed out. If the check result is timed out, the emergency mode control routine is performed.

On the other hand, if it has not timed out, the process returns to step 502 where the CPU _LIU 320 waits for a response from the CPU _FAX 101. The CPU _LIU (320) includes a key so as not to determine if a response is received from the CPU _FAX (101) that the CPU _FAX (101) is powered on, and receives a key code value inputted from the key matrix 250, the process advances to step 503 Generates an input disable signal. The code indicating the disable state is recorded in the key register. In this case, the CPU _LIU 320 of the LIU 108 ignores the key input from the key metrics 350 by reading the disable code recorded in the register, and passes the CPU _FAX 101 through the communication port 340. It is possible to control the dialing operation to occur only for the dial information provided from the.

On the other hand, the memory embedded in the CPU _FAX 101 stores the last dial information, which is the CPU _LIU 320 of the LIU 108 through the communication port 340 when there is a redial key input from the user Is delivered.

After disabling the key matrix input as described above, the process proceeds to step 504 to connect the handset 180 and the path of the telephone line so that a dial tone or signal of the exchange EXH is heard by the handset 180. That is, referring to FIG. 3, the switch unit 350 generates a switch control signal S3 instructing the connection of the voice path VP so that the handset 180 and the telephone line are connected through the speech network 150. Then, the user can hear the confirmation sound at the time of dialing.

The above is an example illustrating a process of confirming that the CPU _FAX 101 is in a power-on state after the LIU 108 is powered on and performing an initialization operation accordingly.

Referring to FIG. 5 again, after the initializing operation of the LIU 108 as described above, in step 505, it is determined whether data or commands, which are previously promised from the CPU _FAX 101, are received through the communication port 340. Check it. At this time, if there is a command or data received, it proceeds to a routine that performs the operation procedure. Otherwise, it waits for the data or command to be received.

For example, when the received data is dial information, the CPU _LIU 320 controls the dialer 360 to dial. When the dialing mode is set as the DTMF mode, the dialer 360 generates a DTMF by combining the high and low group signals (Hz) of the digit and transmits the DTMF according to the transmission level.

Referring to FIG. 6, FIG. 6 relates to an operation in an emulsion mode, that is, when the CPU _FAX 101 is confirmed to be in a power-off state.

If the CPU _LIU 320 in the _LIU 108 is in an emulsion mode as a result of checking the power-off state of the CPU _FAX 101 as described above, as shown in step 601, a key input from the key matrix 250 is shown. It accepts code values and controls dialing. That is, the CPU _LIU 320 generates a key input enable signal and writes it to an internal register. In operation 602, the telephone line and the handset 180 are connected to each other through the voice path VP of the LIU 108 so that the dialing output is made audible to the user when dialing. When a predetermined key input by the key matrix 250 occurs in step 603, the dialer 360 in step 604 indicates that the DTMF dial tone or dial pulse is connected to the tip and ring terminals of the telephone line via the switch unit 350. It is sent out as (T, R).

7 shows an example of a protocol for transmitting and receiving commands and data between the CPU _FAX 101 and the CPU _LIU 320 in the power-on mode. According to FIG. 5 described above, after the power-on initialization is completed, the LIU 108 waits for instructions or dialing digit information from the CPU _FAX 101. In the power-on mode, as described above, a key input to the LIU 108 is performed. Since this is disabled, the key code value from the key matrix 250 is recognized by the CPU _FAX 101, and the recognized key code value is again returned to the CPU _LIU 320 of the _LIU 108 through the communication port 340. FIG. Is passed on.

If a hook event (hook) of the handset 180 occurs by the user in step 701, the CPU _LIU 320 notifies the CPU _FAX 101 in step 702. In response, the CPU _FAX 101 transmits a handset pass set, that is, a voice path command, to the CPU _LIU 320 in step 703. _Upon receiving this command, the CPU _LIU 320 transmits a predetermined response to the CPU _FAX 101 in step 704. When the user inputs a key for dialing through the key matrix 250 in step 705, the CPU _FAX 101 detects the key input and transmits dial information to the CPU _LIU 320 as shown in step 706. . In step 707, the CPU _LIU 320 controls the dialer 360 to cause the dialer 360 to start dialing (assuming DTMF mode) for the digit. Proceed is sent to the CPU _FAX 101 that the dial information has been received. Upon receiving this response, the CPU _FAX 101 continues to transmit the digit to the CPU _LIU 320 as described above if there is another dial number.

In step 709, when a dialing key release input is generated by the user and the CPU _FAX 101 detects this, the CPU _FAX 101 proceeds to step 710 to issue a key release command to the CPU _LIU 320. send. Accordingly, the CPU _LIU 320 controls the dialer 360 in step 711. The CPU _LIU 320 checks the tone sending time at the time when the key release command is received, and determines whether the tone has been transmitted until a preset tone sending time. Check. If the delivery time is short, the generation of the tone is stopped after the transmission to the time that meets the standard, otherwise the generation of the tone is indicated at the present time. In operation 712, the CPU _LIU 320 transmits a response to the key release command to the CPU _FAX 101.

On the other hand, when dialing to the DTMF mode and switching to the DP mode as described above, the CPU _FAX 101 issues a 'DP mode set' command as shown in step 713 to the CPU _LIU ( To 320). In step 714, the CPU _LIU 320 sets the internal register for setting the dialing mode to the DP mode, and transmits a response to the CPU _FAX 101 in step 715. After the CPU _FAX 101 receives the key code value from the key matrix 250 in step 716, the CPU _FAX 101 proceeds to step 717 to transmit dial information about the digit to the CPU _LIU 320. The CPU _LIU 320 receiving the dial information checks the dialing mode by checking the internal register, and the dialer 360 controls the dialing to the corresponding digit in the DP mode in operation 718. After the dialing is completed, the process proceeds to step 719 to transmit a response to the CPU _FAX 101. Upon receiving this response, the CPU _FAX 101 continues to transmit the digit to the CPU _LIU 320 as described above if there is another dial number.

If there is no data or command exchanged between the CPU _LIU 320 and the CPU _FAX 101 for a certain time even during dialing or after answering from the other phone after completing the dialing, the CPU _FAX 101 ) Periodically sends a 'hook state request' command to the CPU _LIU 320. The CPU _LIU 320 then transmits a response, that is, a hook status signal, as shown in step 721. However, if the CPU _FAX 101 does not transmit a command for a predetermined time in step 720, the CPU _LIU 320 determines that the power of the CPU _FAX 101 is turned off and sets the emergency mode. After that, it operates in emulsion mode. In step 722, the CPU _LIU 320 that detects the hook event, that is, the hookup of the handset 180, is notified to the CPU _FAX 101 by the user.

8 is a diagram illustrating a process of converting paths in the LIU 108 by receiving instructions from the CPU _FAX 101.

According to FIG. 8, while performing a dialing procedure (eg, steps 801 and 802) as in FIG. 7 described above, when the user switches to facsimile mode for facsimile transmission in step 803, the CPU _FAX (101). ) Detects this. The CPU _FAX 101 transmits a message of 'modem mode set' to the CPU _LIU 320 as shown in step 804. Upon receiving the message, the CPU _LIU 320 switches the internal path accordingly in step 805. That is, referring to FIG. 3, the switch control signal S1 is generated in a first state (eg, logic high) so that the telephone lines T and R are connected to the modem 107 through the non-voice pass NVP. The switch unit 350 is controlled.

Referring again to Figure 8, after converting the path of the interior, such as the CPU the _LIU (320) is made in step 806 transmits a response to the _LIU CPU (320) the CPU _FAX (101). After again when the user has occurred when to switch to telephone mode, is detected, CPU _FAX (101) of that fact in the 807 step, or the source of a voice call for any other reason the CPU _FAX (101) is the in step 808 CPU Sends a 'handset mode set' command to the _LIU 320. Upon receiving this, the CPU _LIU 320 generates a switch control signal S1 in a second state (eg, a logic low) to the switch 350 to switch an internal path of the LIU 108. That is, the phone lines T and R are connected to the handset 180 via the voice path VP and the speech network 150. After controlling the switching of the internal path as described above, the flow proceeds to step 810 to transmit a response to the CPU _FAX 101 informing the reception and fulfillment of the message.

FIG. 11 is a diagram illustrating a detailed configuration of a line interface circuit according to another exemplary embodiment of the present invention together with its peripheral devices. Referring to FIG. 6, the operation in the emulsion mode, that is, when the CPU _FAX 101 is confirmed to be in the power-off state will be described.

When the CPU _LIU 320 of the LIU 108 checks the power-off state of the CPU _FAX 101 and receives an emergency mode, the CPU _LIU 320 receives the key code value input from the key matrix 250 as shown in step 601. A key input enable signal is generated and written to an internal register so that it can be dialed in. In operation 602, the telephone line and the handset 180 are connected to each other through the voice path VP of the LIU 108 so that the dialing output is made audible to the user when dialing. In step 603, the CPU _LIU 320 scans the key matrix 250 to check for a dial key input. If it is determined that there is a dial key input, the CPU _LIU 320 transfers the corresponding dial information to the dialer 360 in step 604. In this case, the dialer 360 causes the DTMF dialtone or DP corresponding to the dial information to be transmitted to the tip and ring terminals T and R of the telephone line via the switch 350.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, the present invention has the advantage of simplifying the circuit since the dialer, the line interface unit, and the like can be used in common by a non-voice terminal such as a modem and a telephone circuit. In addition, because the circuit is simplified, the overall material cost is reduced, which is an economic advantage. In addition, the LIU automatically connects the voice path during the initialization process when the power is applied to the LIU, so that the user can always check the dialing process by ear. In addition, by unifying the storage location of the LNR information, as there is no confusion for the user as in the prior art, there is an advantage in that the accuracy of dialing can be improved.

Claims (14)

In a line interface circuit which is shared between a voice terminal and a non-voice terminal connected to an exchange through a telephone line and is supplied with an exchanger DC power, With a single dialer, A communication port for communicating with the non-voice terminal, In the power-on state of the non-voice terminal, which converts a predetermined AC power into a direct current, the dial information received from the key matrix to the non-voice terminal is received through the communication port and transmitted to the dialer. And a line interface controller for transmitting dial information, which is directly input from the key matrix, to the dialer when the terminal is powered off. The method of claim 1, And the non-voice terminal is a modem having a function of analog conversion of data to be transmitted or digital conversion of received data so that a computer can transmit and receive data through the telephone line. The method of claim 1, And said non-voice terminal is a modem for modulating and demodulating image data so as to transmit and receive a facsimile manuscript through said telephone line. In a telephone communication system having a modem, a main controller, a key matrix, and a handset, a line interface circuit using a different power source than the main controller, A line interface unit connected to the exchange via a telephone line and matching the impedance with the exchange; A speech network for amplifying a voice signal received through the telephone line and transmitting the amplified voice signal to the handset; A modem interface unit connected to the modem and matching an impedance between the modem and the switch; A dialer for dialing according to dial information transmitted from the key matrix by a user's key input; A switch unit selectively connected to the speech network or the modem interface unit for connecting a voice path or a non-voice path between the telephone line and the speech network or the telephone line and the modem interface unit; A communication port connected at one side to the main control unit; Is connected to the other side of the communication port and performs data and message communication with the main control unit, and checks the power on or off state of the main control unit to set a power on mode or an emergency mode, in the power on mode the communication port The dialer transmits the dial information transmitted from the main controller to the dialer, and in dialer mode, the dialer information input from the key matrix is transmitted to the dialer and generates a switch control signal for controlling the switch unit. Circuit comprising a line interface control unit. The method of claim 4, wherein And said modem modulates and demodulates the image data so as to transmit and receive a facsimile manuscript. The method of claim 4, wherein And said modem performs analog conversion of data to be transmitted or digital conversion of received data so that a computer can transmit and receive data through said telephone line. The method of claim 4, wherein the dialer, And generating a dual tone multi-frequency or dial pulse according to the dial information transmitted from the line interface unit. The method of claim 4, wherein A hook state detecting unit is further provided to detect a hook off, and the line interface controller notifies the hook-off state to the line interface controller, and the line interface controller notifies the main controller of the hook-off state through a communication port, and then selects a path from the main controller. And receiving a switch control signal so that the telephone line and voice path or modem path are connected accordingly. The method of claim 4, wherein And a line current sensing unit for detecting a current amount change of the telephone line and transferring the current amount change to the line interface control unit, wherein the line interface control unit generates a message regarding a line state according to the change amount of the current amount, and transmits the message through the communication port. A circuit characterized by transmitting to the main control. The method of claim 4, wherein the line interface circuit, The switch is operated by receiving a DC power supply, the main control unit, characterized in that for converting a predetermined AC power to direct current. In a telephone communication system in which a non-voice terminal and a voice terminal are connected to a telephone line through a shared line interface circuit, a control unit of the line interface circuit communicates with a main controller of the telephone communication system to control an interface with an exchange. , A first step of transmitting a hook-off status signal to the main controller when detecting a user's handset hook-off; A second step of checking whether a response is received from the main controller within a predetermined time after transmission of the hook-off state signal, and if there is a response, setting an operation mode to a power-on mode; A third step of connecting the phone line and the voice path when the operation mode is set in the second step; And a fourth step of checking whether dial information is received according to the operation mode after connecting the telephone line with the voice path. The method of claim 11, wherein in the second process, And if there is no response for a predetermined time from the main controller, setting the operation mode to an emergency mode. The method of claim 12, wherein in the third process, And set the key input disable state when the operation mode is the power-on mode, and set the key input enable state when the operation mode is an emergency mode. In a line interface circuit which is shared between a voice terminal and a non-voice terminal connected to an exchange through a telephone line and is supplied with an exchanger DC power, A dialer for dialing by receiving dial information directly from a key matrix in a power-off state of the non-voice terminal; A communication port for communicating with the non-voice terminal, The line interface controller which receives dial information input from the key matrix to the non-voice terminal through the communication port and transmits the dial information to the dialer in a power-on state of converting a predetermined AC power into a direct current. Circuit, characterized in that consisting of.

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