JPH0723129A - Configuration method for network control circuit - Google Patents

Abstract

PURPOSE:To allow the circuit to be in compliance with each country standard simply by providing a means revising an electric specification of the network control circuit through its internal operation and setting the electric specification in compliance with a country in which the circuit is in use automatically. CONSTITUTION:A facsimile equipment reads a country number in a nonvolatile RAM in a memory and reads control data corresponding to the country number from a ROM. The electric specification for a termination circuit 111 and a ringing detection circuit 112 is controlled based on read control data. That is, the circuit 112 applies on/off control to a photocoupler to set a detection condition of a ringing signal. Furthermore, the circuit 111 applies on/off control to a switch according to control data to take impedance matching with a telephone line. Furthermore, a DC loop current flows into a DC resistance circuit 109 and a current sensor, the voltage current characteristic is specified differently by each country and a constant voltage current characteristic to meet the standards of any country is devised.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a network control circuit which is connected to a telephone line of each country and which operates with electrical specifications complying with the standards of each country.

[0002]

2. Description of the Related Art Various communication devices, such as a facsimile machine, which communicate via a telephone network detect various signals received from an exchange when making and receiving a call, and send dial signals to the exchange. A network control circuit is provided.

The electrical specifications of the telephone network are usually determined by the country or company in which they are installed, and therefore differ somewhat from country to country. For this reason, the electrical specifications required for the network control circuit, that is, the standards of the network control circuit, differ somewhat from country to country.

For example, the network control circuit needs to perform impedance matching with the telephone line, but the standard value of the return loss for this impedance matching may differ from country to country.

Further, the network control circuit detects a ringing signal at the time of an incoming call and connects the line. At this time, a DC loop current is passed between the two lines of the line.

In this case, the standard value of the signal frequency or signal voltage to be judged as a ringing signal, or the standard relating to the DC loop current may differ from country to country.

Therefore, when shipping a manufactured communication device to each country, the communication device manufacturer adjusts the electrical specifications in the network control circuit so as to meet the standards of the shipping country.

Conventionally, in this case, for example, as shown in FIG. 13, a terminal T is provided in the network control circuit, and the terminal T is provided.
In addition, parts P such as resistors and capacitors having various values are soldered to adjust the electrical specifications.

On the other hand, during the communication operation of the communication device, the billing signal is exchanged between the exchanges of the telephone line network to manage the telephone charges. The billing signal is a 16 kHz signal. The communication device, together with the data signal, is 16K
If the Hz signal is received, the original communication will be hindered. Therefore, such a communication device is usually provided with a filter circuit for removing the 16 KHz component of the received signal.

Conventionally, such a filter circuit has been arranged on the output side of the network control circuit, for example, on the input side of the modem in the case of a facsimile machine. In this case, the filter circuit is a low-pass filter of a complex circuit having a multistage structure.

Further, since the above-mentioned DC loop current at the time of line connection has a circuit configuration to be passed through the winding of the transformer, it is necessary to thicken the winding of the transformer and increase the iron core.

[0012]

Conventionally, in order to match the electrical specifications of the network control circuit with the standards of each country, it is necessary to mount different parts for each country as described above, which is troublesome. There was a problem that it took time.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and provide a method of configuring a network control circuit capable of easily adjusting electrical specifications to the standards of each country without trouble.

[0014]

To this end, in one invention of the present application, a means for changing the electrical specifications of the network control circuit by internal operation is provided, and the country to be used is arbitrarily specified, so that The electrical specifications complying with the standard are automatically set.

According to another aspect of the invention, the DC loop current is made to flow with a constant characteristic that simultaneously satisfies the standards of a plurality of countries.

[0016]

According to the above-mentioned one invention, since the operator only has to specify the country to be used, the electrical specifications can be easily adjusted to the standards of each country without trouble. Further, according to another invention, with respect to the standard of the DC loop current, the work for adjusting the standard is unnecessary.

[0017]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a facsimile apparatus according to an embodiment of the present invention. In the figure, a network control circuit 1 is connected to a telephone line and detects various signals received from an exchange and sends a dial signal to the exchange when a call is made or received. The telephone 2 is used for a call. The modem 3 transmits / receives a transmission control procedure signal and image information during facsimile communication. The facsimile image processing unit 4 reads image information from a document and compresses the data, or restores the received compressed data to the original image information and prints it on a recording sheet.

The voice response unit 5 sends out a fixed voice message. The operation display unit 6 displays the operating state of the device while the operator performs various operations. The memory 7 is composed of a ROM and a non-volatile RAM, and stores a control program and various data. The system control unit 8 is a microcomputer that monitors and controls the above units.

FIG. 2 shows a circuit configuration of the network control circuit 1. In the figure, one line of the telephone line is connected to the common terminal c ↓ 1 of the changeover switch 101, and the other line is connected to the common terminal c ↓ 2 via the current sensor 102. The current sensor 102 includes a DC detection circuit 1
03 and the CNG detection circuit 104 are connected.

The contact a ↓ 1 of the changeover switch 101 is LC
One end of the input of the rectifier circuit 106 is connected through the filter 105, and the contact a ↓ 2 is directly connected to the other end. The LC filter 105 is a resonance circuit having a set of a coil and a capacitor, and the resonance frequency is set to 16 kHz. The rectifier circuit 106 has four diodes bridge-connected.

The + side of the output of the rectifier circuit 106 is connected to the collector of the transistor of the photocoupler 107 and the switch 10
8 is connected to one contact, and the negative side is connected to the photocoupler 1
07 transistor emitter and DC resistance circuit 109
And one end of one winding of the transformer 110, respectively. The other end of the switch 108 is connected to the other end of the DC resistance circuit 109, and the capacitor C
1 to the other end of the winding.

One end of the other winding of the transformer 110 is grounded, and the other end is connected to the termination circuit 111. The reception signal is input to the modem 3 from the other end of the winding, and the transmission signal of the modem 3 is input to the termination circuit 111.

Contact points b ↓ 1, b ↓ 2 of the changeover switch 101
Are connected to the ringing detection circuit 112 and the telephone 2, respectively.

A fixed voltage + V is applied to the anode of the photodiode in the photocoupler 107, and the cathode thereof is connected to the system controller 8. Further, the detection signals of the DC detection circuit 103, the CNG detection circuit 104, and the ringing detection circuit 112 are input to the system control unit 8, and the system control unit 8 switches the changeover switch 1
01, switch 108 and ringing detection circuit 112
The control signal is input to.

FIG. 3 shows the circuit configuration of the ringing detection circuit 112. In the figure, the line of the contact b ↓ 1 of the changeover switch 101 is connected to one end of the resistor R2 and one end of the input of the rectifier circuit 1122 via the switch 1121, the capacitor C2, and the resistor R1. Further, the line of the contact b ↓ 2 of the changeover switch 101 is directly connected to the resistor R2.
And the rectifier circuit 1122 are connected to the other ends thereof.

The + side of the output of the rectifier circuit 1122 has a resistor R
2 to R4, and the cathode of the Zener diode D1. The other end of the resistor R3 is connected to the collector of the transistor of the photocoupler 1123. The other end of the resistor R4 is the photocoupler 11
It is connected to the collectors of 24 transistors. The anode of the Zener diode D1 is a photo coupler 1125.
Is connected to the anode of the photodiode. The minus side of the output of the rectifier circuit 1122 is connected to the photocoupler 1
The emitters of the transistors 123 and 1124 and the cathode of the photodiode of the photocoupler 1125 are connected, respectively.

A constant voltage + V is applied to the collector of the transistor of the photocoupler 1125, and its emitter is grounded. The signal voltage of the collector is input to the system controller 8. Also, the photo coupler 112
A constant voltage + V is applied to the anodes of the photodiodes 3 and 1124, and their cathodes are connected to the system control unit 8. In addition, a control signal is input from the system control unit 8 to the switch 1121.

FIG. 4 shows the circuit configuration of the termination circuit 111. In the figure, one ends of resistors R5 and R6 and a capacitor C3 are connected to the winding line of the transformer 110, respectively. The other end of the resistor R5 is connected to the output of the modem 3 via the switch 1111.
Similarly, the other end of the resistor R6 is connected via the switch 1112, and the other end of the capacitor C3 is connected via the switch 1113 to the modem 3
Respectively connected to the output of. Switches 1111 to 1111
A control signal from the system control unit 8 is input to 1113.

The DC resistance circuit 109 is composed of resistors, capacitors, diodes and transistors, although the circuit structure is not shown. This DC resistance circuit 10
Reference numeral 9 is a circuit for supplying a prescribed DC loop current to the line when the network control circuit 1 is connected to the line, that is, in an off-hook state.

With the above configuration, the network control circuit 1 of the facsimile apparatus of this embodiment has the function of complying with the electrical standards of a plurality of countries.

Now, for example, assuming that it has a function conforming to the electrical standards of three countries, the RO of the memory 7
In M, as shown in FIG. 5, the country numbers and control data for the three countries, A to C, are stored in advance. This control data is for changing the electrical specifications of the network control circuit 1.

The facsimile apparatus of this embodiment is, for example,
Set the country code when manufacturing at the factory and shipping to each country. In this case, as shown in FIG. 6, the operator sets the country code indicating the destination of the device by a predetermined operation (process T).
101). The facsimile device stores the input country code in the nonvolatile RAM in the memory 7 (process T10).
2).

Next, it is assumed that the facsimile apparatus is installed in the country of the destination and the apparatus power is turned on. In this case, as shown in FIG.
Read the country code of the non-volatile RAM in (T20
1) Further, the control data corresponding to the country code is read from the ROM (process T202).

Then, the electrical specifications of the termination circuit 111 and the ringing detection circuit 112 are controlled based on the read control data. That is, the ringing detection circuit 11
In 2, the photocouplers 1123 and 1124 are controlled to a constant on / off state according to the control data. This is a control for setting the detection condition of the ringing signal. Further, in the termination circuit 111, the switches 1111 to 1113 are controlled to a constant on / off state according to the control data. This is a control for impedance matching with the telephone line (process T203).

Next, when the calling process is executed by this facsimile apparatus, as shown in FIG. 8, the operator sets a destination and activates the calling operation (process T301). When the facsimile apparatus is activated, the switch 101 is switched and connected to the contact a side (process T302). Then, the switch 108 is closed (process T303).

In this case, a DC circuit is formed by the changeover switch 101, the LC filter 105, the rectifying circuit 106, the switch 108, the DC resistance circuit 109 and the current sensor 102, and a DC loop current flows.

The standards of each country specify the voltage / current characteristics in this case. Here, FIG. 9A shows the standard Sa of country A conforming to the present embodiment, FIG. 9B shows the standard Sb of country B, and FIG. 9C shows the standard Sc of country C. It is assumed that In these figures, the horizontal axis represents the DC loop current, the vertical axis represents the DC voltage between the two lines, and the hatched area represents the standard range.

In this embodiment, the DC resistance circuit 109 is designed so as to show a constant voltage / current characteristic F that satisfies all the standards Sa to Sc of the above three countries, as shown in FIG. As a result, even if the facsimile machine is installed in any of the above-mentioned three countries, it conforms to the standards of the voltage / current characteristics of that country.

After that, the facsimile machine switches to the switch 1
Open 08 and according to the other party's number, photocoupler 1
07 is turned on / off. As a result, a dial pulse is sent to the line and is sent to the other party (process T30).
4). The switch 108 is closed again when the transmission of the dial pulse is completed.

When the other party responds, a predetermined facsimile communication operation is executed.

In this case, the received signal is input to both ends of the DC resistance circuit 109 in the same circuit as the DC loop, and further to the modem 3 via the capacitor C1 and the transformer 110.

The transmission signal of the modem 3 is the termination circuit 1
11 is input. Switch 1111 of termination circuit 111
˜1113 are on / off controlled to a constant state by the control data. In the present embodiment, this control causes one or both of the resistors R5 and R6 to be inserted into this circuit. Further, the capacitor C3 is inserted in this circuit as needed. Therefore, the input transmission signal is the resistance R5,
It is input to the transformer 110 via R6 and the capacitor C3, and is sent out to the line through a route opposite to the above circuit. In this way, facsimile communication is executed.

By the way, the terminating circuit 111 serves to perform impedance matching between the telephone line and the modem 3. According to the standard, this impedance matching has a return loss of 1 for a line with an impedance of 600Ω, for example.
It is regulated to be 4 dB or more. In this embodiment, as described above, the resistors R5 and R6 and the capacitor C are used.
3 is inserted into the circuit as needed to adjust the impedance so as to satisfy the standard of the return loss of each country.

On the other hand, during such communication, a billing signal exchanged between the exchanges of the telephone network may be received. This billing signal is a 16 kHz signal. The LC filter 105 is an LC resonance circuit tuned to the 16 kHz. As a result, the billing signal is removed and the modem 3 is prevented from receiving.

Next, the incoming operation of this facsimile will be described.

During standby of the facsimile apparatus, the changeover switch 101 is changed over and connected to the side b, and the switch 1121 of the ringing detection circuit 112 is closed.

If an incoming call is received, the ringing signal received from the telephone line is input to the ringing detection circuit 112. Since the ringing signal is an alternating current, in this case, the switch 1121, the capacitor C2 and the resistor R1.
Through the resistor R2 and the rectifier circuit 1122. The current flowing into the rectifier circuit 1122 is rectified here.

As described above, the photocouplers 1123 and 1124 are controlled to a constant on / off state by the control data. When the photocoupler 1123 is on, the resistor R3 is connected to the output of the rectifier circuit 1122. Similarly, when the photocoupler 1124 is on, the resistor R4 is connected. The output current of the rectifier circuit 1122 is the resistance R3.
When R4 is connected, it flows through those resistors, the Zener diode D1 and the diode of the photocoupler 1125.

A current flows through the Zener diode D1 when the voltage across the Zener diode D1 exceeds a certain voltage. Further, the photodiode of the photocoupler 1125 also lights up when the voltage across it becomes equal to or higher than a certain voltage.

Therefore, when the input voltage to the ringing detection circuit 112 becomes a certain voltage value or more, the photodiode of the photocoupler 1125 is turned on. In this case, the constant voltage becomes higher when the resistors R3 and R4 are connected.

By the way, the standard of the detection condition of the ringing signal is defined by the signal frequency and the voltage value such as "detection" when the voltage is 18 V or more at 40 to 60 Hz and "non-detection" when the voltage is 10 V or less. There is.

In this embodiment, the connection state of the resistors R3 and R4 is switched according to the control data so that the ringing signal detection condition conforms to the standards of each country.

As a result, when the prescribed ringing signal is received, the photocoupler 1125 is turned on and the system controller 8 detects the incoming call.

When the facsimile machine is on standby, the facsimile machine shown in FIG.
As shown in FIG.
N loops). When an incoming call is detected (process T4
(Y of 01), the changeover switch 101 is changed over and connected to the side a (process T402).

Then, the reception of the CNG signal is monitored (process T403). The CNG signal is a 1100 Hz tone signal that is first transmitted by the facsimile apparatus on the transmitting side, and is detected by the current sensor 102 and the CNG detection circuit 104.
When this CNG signal is detected (Y in processing T403), a predetermined facsimile communication operation is executed as in the case of the above-mentioned transmission.

On the other hand, if the other party is a person making a call from the telephone, the CNG signal is not received. In this case (N in process T403), for example, a voice message such as "I am now connected to a facsimile machine." Is transmitted (process T404), and the operation ends. This voice message is output from the voice response unit 5 and input to the ringing detection circuit 112 (not shown). As a result, it is transmitted in the same manner as the transmission signal of the modem 3.

Next, the operator takes the telephone 2 off hook when making a call from the telephone 2.

The facsimile apparatus of the present embodiment is waiting,
As shown in FIG. 12, the off-hook of the telephone 2 is monitored (process T501). That is, the changeover switch 101
Is switched to the b side during standby, so the telephone 2
The off-hook causes a DC loop current to flow in the line. The current sensor 102 and the DC detection circuit 103 detect the DC loop current. This DC loop current causes the telephone 2
Determine the hook status of.

In this embodiment, when the telephone 2 is off-hook (Y in processing T501), the ringing detection circuit 11 is used.
2 switch 1121 is opened (process 502), and telephone 2
Is switched on hook (from N in process T501 to Y in process T503), the switch 1121 is closed (process T504).

The operator operates the telephone 2 after going off hook. As a result, a dial pulse is output from the telephone 2 and sent to the line. Then, when the other party answers, the call becomes possible.

As described above, in this embodiment, the network control circuit 1 is provided with means for changing the electrical specifications such as the return loss of the received signal and the detection condition of the ringing signal, and when the operator inputs the country code. , The electrical specifications that comply with the standards are automatically set in the corresponding country. Further, the DC resistance circuit 109 is set to have a constant voltage / current characteristic that simultaneously satisfies the standards of a plurality of countries.

As a result, the troublesome work of attaching different parts depending on the country of use as in the past is not necessary, and the electrical specifications can be easily adjusted to the standards of each country without trouble. .

The received signal of 16 kHz is received by the LC filter 105, which is a resonance circuit of one set of a coil and a capacitor.
The circuit configuration is simplified because it is prevented by.

The DC loop current is the DC resistance circuit 1
The transformer 110 can be constructed in a small size because it is allowed to flow in the transformer 09 and not to the transformer 110.

When the telephone 2 is off-hook, the switch 1121 is opened. When the dial pulse output from the telephone 2 flows into the capacitor C2, the pulse waveform becomes dull, and there is a risk that the exchange station may cause a dial signal reading error. In this embodiment, when the operator dials, the switch 1121 is opened, so that the dial pulse does not flow into the capacitor C2 and the reading error of the dial signal is prevented.

In the above embodiment, the country code is input to automatically set the ringing signal detection condition and the termination circuit specification. However, other electrical specifications may be automatically set in the same manner. Can also be considered.

Although the facsimile apparatus has been described as an example, it goes without saying that the present invention can be similarly applied to various communication apparatuses having a network control circuit.

[0069]

As described above, according to one invention of the present application, a means for changing the electrical specifications of a network control circuit is provided, and the country to be used is simply designated to comply with the standard of that country. Therefore, the operator can easily adjust the electrical specifications to the standards of each country without trouble.

Further, in another invention, since the DC loop current is made to flow with a constant characteristic that simultaneously satisfies the standards of a plurality of countries, it is also necessary to work on the standard of the DC loop current. Disappears.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a facsimile apparatus according to an embodiment of the present invention.

FIG. 2 is a circuit configuration diagram of a network control circuit.

FIG. 3 is a circuit configuration diagram of a ringing signal detection circuit.

FIG. 4 is a circuit configuration diagram of a termination circuit.

FIG. 5 is an explanatory diagram of information stored in a ROM.

FIG. 6 is a flowchart of a setting process when the device is shipped.

FIG. 7 is an operation flowchart when the apparatus power is turned on.

FIG. 8 is a flowchart of a calling process.

FIG. 9 is a graph showing a standard example of each country regarding a line loop current.

FIG. 10 is a graph showing voltage-current characteristics of a DC resistance circuit.

FIG. 11 is a flowchart of an incoming call operation.

FIG. 12 is a flowchart of the control operation of the facsimile apparatus when using the telephone.

FIG. 13 is an explanatory diagram of a conventional setting method for setting electrical specifications.

[Explanation of symbols]

 1 Network Control Circuit 2 Telephone 3 Modem 4 Facsimile Image Processing Section 5 Voice Response Section 6 Operation Display Section 7 Memory 8 System Control Section 101 Changeover Switch 102 Current Sensor 103 DC Detection Circuit 104 CNG Detection Circuit 105 LC Filter 106, 1122 Rectification Circuit 107 , 1123 to 1125 Photocoupler 108, 1111 to 1113, 1121 Switch 109 DC resistance circuit 110 Transformer 111 Termination circuit 112 Ringing detection circuit C1 to C3 Capacitor D1 Chener diode R1 to R6 Resistance

Claims (6)

[Claims] 1. A method of configuring a network control circuit connected to a telephone line of each country and operating according to the electrical specifications conforming to the standards of each country, comprising means for changing the electrical specifications of the network control circuit by internal operation. A method for configuring a network control circuit, characterized by automatically specifying electrical specifications that comply with the standards of a country by arbitrarily specifying the country of use. 2. The above-mentioned standard is a condition for detecting a ringing signal received from a telephone line.
A method for configuring a network control circuit as described. 3. The method for configuring a network control circuit according to claim 1, wherein the standard is a return loss for a received signal received from a telephone line. 4. A method for constructing a network control circuit that is connected to a telephone line of each country and operates by applying a DC loop current to the telephone line with characteristics conforming to the standards of each country. A method for configuring a network control circuit, characterized in that it comprises means for operating a DC loop current with a constant characteristic. 5. A method of constructing a network control circuit comprising means for blocking a reception signal of 16 kHz received from a telephone line, wherein the reception signal is blocked by a pair of resonance circuits of a coil and a capacitor. A method for constructing a characteristic network control circuit. 6. A method of constructing a network control circuit which is connected to a telephone line and operates by supplying a DC loop current to the line, wherein the DC loop current is passed through a circuit other than a winding of a transformer in the network control circuit. A method of constructing a network control circuit, characterized in that the network control circuit flows.