JP2000125037A - Terminal network controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely enable a telephone set to be used even if a relay for connecting and disconnecting a telephone line to/from the telephone set malfunctions. SOLUTION: This controller is provided with a communication process part 3 which performs line connection control and communication control of a telephone line 2, a meter interface part 8 which communicates with a meter terminal, a relay part 5 which connects and disconnects the telephone line 2 to/from an externally connected telephone set 4, a contact state detection part 6 which detects the state of the connection between the telephone line 2 and telephone set 4 at the relay part, and a control part 7 which controls the communication process part 3, the meter interface part 8 and the relay part 5, then the contact state detection part 6 detects the disconnection part although relay disconnection control from the control part 7 is not performed while the telephone line 2 and telephone set 4 are connected by the relay part 5. Consequently, the telephone set can be used even if the relay part 5 malfunctions by controlling the relay part 5 into the connection state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a terminal network control device.

[0002]

2. Description of the Related Art FIG. 7 shows a block diagram of a conventional terminal network control device. In FIG. 1, reference numeral 1 denotes a terminal network control device which is connected to a telephone line 2 via terminals L1 and L2, and an input of which is connected to a communication processing unit 3 for controlling connection with the telephone line 2, performing modem communication and the like. The terminals L1 and L2 are connected to a relay unit 5 for connecting / disconnecting to / from the terminals T1 and T2 to which the telephone 4 is connected. This relay unit 5 uses a well-known mechanical latching relay (not shown). ing. The terminals L1 and L2 are terminals for connecting a meter terminal such as a gas meter, and communicate with the control unit 7 via the meter interface unit 8. The control unit 7 controls the energization of the coil of the relay unit 5 and controls the communication processing unit 3 upon detecting the reversal of the polarity of the telephone line 2. It operates to perform a no-ringing signal (hereinafter, referred to as an NRS signal) reception processing, a subsequent no-ringing communication for performing data communication, and a terminal call communication operation for calling from the meter terminal.

[0003]

On the other hand, in the conventional terminal network control device, since a mechanical latching relay is used for the relay section 5, the latching relay is inverted due to an external impact or the like, and is connected to the telephone line. There is a problem that the telephone is disconnected and the telephone cannot be used.
The present invention is to solve such a conventional problem,
An object of the present invention is to provide a terminal network control device for preventing a telephone from becoming unusable.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention detects a state in which a telephone line is disconnected from a telephone due to a malfunction of a relay and immediately connects the telephone line to the telephone. Thus, means for resetting the latching relay is provided. The resetting means prevents the telephone line from being disconnected from the telephone so that the telephone cannot be used.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to solve the above-mentioned problems, a communication processing unit for controlling line connection and communication control with a telephone line, a meter interface unit for communicating with a meter terminal, Connection with telephone connected to
A relay unit that disconnects, a contact state detection unit that detects a connection state between the telephone line of the relay unit and a telephone, and controls the communication processing unit, the meter interface unit, and the relay unit, and the relay unit. A control unit that operates the relay to the connected state by detecting the disconnected state by the contact state detecting unit even though the relay disconnection control from the control unit is not performed while the telephone line and the telephone are connected. Is provided, it is possible to reduce a state in which the telephone is disconnected from the telephone line due to a malfunction of the relay unit and the telephone cannot be used.

[0006] Further, by detecting the output of the contact state detecting section by the interrupt input of the microcomputer constituting the control section, it is possible to shorten the time from occurrence of a malfunction of the relay to resetting of the relay.

Further, by configuring the contact state detecting section to operate with the power of the telephone line, the contact state detecting section does not operate when not connected to the telephone line, and the terminal network control device is connected to the telephone line. It is possible to prevent wasteful consumption of electric power until installation.

Further, by providing a control unit for stopping the communication operation when the contact state detecting unit detects a malfunction of the relay during the communication operation, it is possible to prevent the malfunction of the communication.

Further, by configuring the control unit to periodically check the output of the contact state detection unit, it is possible to reliably cope with a malfunction of the relay.

[0010]

An embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1) In FIG. 1, reference numeral 1 denotes a terminal network controller which is connected to a telephone line 2 via terminals L1 and L2, and whose input performs connection control with the telephone line 2, modem communication, and the like. It is connected to the communication processing unit 3. Also, terminals L1,
L2 is a connection between terminals T1 and T2 to which telephone 4 is connected.
The relay unit 5 is connected to a disconnecting relay unit 5. The relay unit 5 uses a well-known mechanical latching relay (not shown). Although not shown, the latching relay is provided with a set coil and a reset coil. By outputting a pulse to the output terminals 7a and 7b of the control unit 7, the built-in contact can be controlled to a disconnected / connected state. .

The relay section 5 is connected to a contact state detecting section 6 for detecting whether or not the contact of the relay is connected between the telephone line 2 and the telephone 4. The output of the relay section 5 is an input terminal 7c of the control section 7. Is input to Also, terminals M1, M2
Is a terminal for connecting a meter terminal such as a gas meter,
The communication with the control unit 7 is performed via the meter interface unit 8.

The control unit 7 is constituted by a well-known microcomputer (hereinafter referred to as a microcomputer), and controls the energization of the coil of the relay unit 5 and the contact state detection unit 6.
When the output of the telephone line 2 is detected and when the polarity reversal of the telephone line 2 is detected, the communication processing unit 3 is controlled, and although not shown, the modem circuit and the like provided in the communication processing unit 3 are operated to perform NRS signal reception processing and subsequent processing. No ringing communication for performing data communication and a terminal call communication operation for calling from the meter terminal.

FIG. 2 shows waveforms at essential parts for explaining the above operation. Waveform (2-1) is a voltage waveform at terminals T1 and T2, and V1 is normally 48V. A waveform (2-2) is an output waveform of the contact state detector 6. In addition, the waveform (2-
3) is a voltage waveform at the output terminal 7a of the control unit 7. Normally, the line voltage V1 is applied to the terminals T1 and T2 from the telephone line. However, when the contact of the relay unit 5 is reversed at time t1 due to an impact or the like and the terminals T1 and T2 are disconnected from the terminals L1 and L2,
No voltage is applied to the terminals T1 and T2.

This state is detected by the contact state detecting section 6 and a waveform as shown by a waveform (2-2) is outputted and inputted to the input terminal 7c of the control section 7. When the control unit 7 detects the signal from the contact state detection unit 6 after the time T2, the output terminal 7
The reset pulse shown in waveform (2-3) is output to b.
With this reset pulse, the contact of the relay unit 5 becomes the terminal L
1, L2 and terminals T1, T2.

(Embodiment 2) FIG. 3 shows an input terminal 7 of the control unit 7.
7 is a flowchart (a) and (b) showing processing of the microcomputer when c is processed as an interrupt input of the microcomputer. The flowchart (a) shows the operation of the interrupt processing. When a signal in which the relay section 5 malfunctions is input to the input terminal 7c of the control section 7, the interrupt processing 9 is processed, and in step 10, the relay section 5 is reset. Then, a relay reset flag RF indicating whether or not to perform is set to 1, and in step 11, other necessary processing as a terminal network control device is performed, and the interrupt processing is completed. The flowchart (b) shows the operation of the main processing,
In step 12, the relay reset flag RF is confirmed. If the relay reset flag RF is not set, in step 15, processing such as a communication operation as a terminal network control device is performed. If it is confirmed in step 12 that the relay reset flag RF is set, the relay reset flag RF is reset to 0 in step 13 and a relay reset process of outputting a reset pulse from the output terminal 7b of the control unit 7 in step 14 is performed. Work to do.

(Embodiment 3) In FIG.
Is provided with a diode bridge 3a, which operates to make the polarity of the telephone line 2 non-polar. The relay unit 5 includes a contact composed of the contacts 5a to 5f, a set coil (not shown) for setting the contact to a broken line, and a reset coil for setting the contact to a connection indicated by a solid line. 7 are controlled by pulses output from output terminals 7a and 7b.

The contact state detector 6 is connected to the contacts 5c and 5f of the relay unit 5 and includes diodes 6a and 6b, a protection resistor 6c, a bias resistor 6d, and a transistor 6e. When the contact point of the relay section 5 is switched to the state shown by the dotted line due to malfunction, the base current flows to the transistor 6e via one of the diodes 6a and 6b and the resistor 6c through the relay contact from one of the terminals L1 and L2 having a positive potential. Flows,
The transistor 6e is turned on, and the state is input to the input terminal 7c of the control unit 7. Since the transistor 6e operates with the voltage applied to the terminals L1 and L2, when the telephone line 2 is not connected to the terminals L1 and L2, the transistor 6e operates even if the contact of the relay unit 5 is in a broken line state.
Does not work. Therefore, when the terminals L1 and L2 are not connected to the telephone line 2, the control unit 7 and the relay unit 5 do not operate, so that it is possible to suppress the power consumption of the power supplied to the circuit.

(Embodiment 4) FIG. 5 shows a waveform diagram of a main part of the terminal network control device 1. A waveform (5-1) is a voltage waveform at the terminals T1 and T2, a waveform (5-2) is a diagram showing a communication state of the communication processing unit 3, and a waveform (5-3) is an output waveform at the output terminal 7b of the control unit 7. Is shown. At time t1, when the contact of the relay unit 5 is switched due to an impact or the like and the voltage of the telephone line 2 stops being generated at the terminals T1 and T2, the contact state detecting unit 6 detects the state and the communication processing unit 3 is communicating. For example, the processing is stopped at time t2. Thereafter, the control unit 7 outputs a reset pulse to the output terminal 7b at time t3, and returns the relay unit 5 to the reset state.

(Embodiment 5) FIG. 6 shows an input terminal 7 of the controller 7.
7 is a flowchart (a) and (b) showing processing of the microcomputer when c is processed as an interrupt input of the microcomputer. The flowchart (a) shows the operation of the interrupt processing. When a signal in which the relay section 5 malfunctions is input to the input terminal 7c of the control section 7, the interrupt processing 9 is processed, and in step 10, the relay section 5 is reset. Then, a relay reset flag RF indicating whether or not to perform is set to 1, and in step 11, other necessary processing as a terminal network control device is performed, and the interrupt processing is completed. The flowchart (b) shows the operation of the main processing,
In step 12, the relay reset flag RF is confirmed. If the relay reset flag RF is not set, in step 15, processing such as communication operation as a terminal network control device is performed. If it is confirmed in step 12 that the relay reset flag RF is set, the relay reset flag RF is reset to 0 in step 13 and a relay reset process of outputting a reset pulse from the output terminal 7b of the control unit 7 in step 14 is performed. Work to do.

In step 16, a timer counting a predetermined time is monitored, and when the predetermined time has elapsed, step 17 is processed. In step 17, the level of the input terminal 7c of the control unit 7 is confirmed, and if it is detected that the contact of the relay unit 5 is malfunctioning, the relay reset flag RF is set to 1 in step 18. When this relay reset flag is set to 1, step 1
2, the relay unit 5 is configured to perform a reset operation in the same manner as described above.

[0022]

As described above, according to the present invention, while the relay disconnection control is not performed from the control unit while the telephone line and the telephone are connected by the relay unit, the contact state detection unit is disconnected. By providing a control unit that operates the relay to the connected state by detecting the state,
It is possible to reduce the state in which the telephone is disconnected from the telephone line due to the malfunction of the relay and the telephone cannot be used.

Further, by detecting the output of the contact state detecting section by the interrupt input of the microcomputer constituting the control section, it is possible to shorten the time from occurrence of a malfunction of the relay to resetting of the relay.

Further, by configuring the contact state detector to operate with the power of the telephone line, the contact state detector does not operate when the terminal network controller is not connected to the telephone line, and the terminal network control device is connected to the telephone line. It is possible to prevent wasteful consumption of electric power until installation.

Further, by providing a control unit for stopping the communication operation when the contact state detecting unit detects a malfunction of the relay during the communication operation, it is possible to prevent the malfunction of the communication.

Further, by configuring the control unit to periodically check the output of the contact state detection unit, it is possible to reliably cope with a malfunction of the relay.

[Brief description of the drawings]

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

FIG. 2 is a timing chart of the apparatus.

FIG. 3A is a flowchart of an external input interrupt process of the microcomputer of the terminal network control device according to the second embodiment of the present invention. FIG. 3B is a flowchart of a main process of the microcomputer.

FIG. 4 is a block diagram of a terminal network control device according to a third embodiment of the present invention.

FIG. 5 is a timing chart of a terminal network control device according to a fourth embodiment of the present invention.

FIG. 6A is a flowchart of an external input interruption process of the microcomputer of the terminal network control device according to the fifth embodiment of the present invention. FIG. 6B is a flowchart of a main process of the microcomputer.

FIG. 7 is a block diagram of a conventional terminal network control device.

[Explanation of symbols]

 Reference Signs List 1 terminal network control device 2 telephone line 3 communication processing unit 4 telephone 5 relay unit 6 contact state detection unit 7 control unit 8 meter interface unit

Claims (5)

[Claims] 1. A communication processing unit for controlling line connection and communication with a telephone line, a meter interface unit for communicating with a meter terminal, and a connection / disconnection between the telephone line and an externally connected telephone. A relay unit to perform, a contact state detection unit that detects a connection state between a telephone line of the relay unit and a telephone, a control unit that controls the communication processing unit, the meter interface unit, and the relay unit. A terminal that operates the relay unit in the connected state by detecting the disconnected state by the contact state detecting unit even though the control unit does not perform disconnection control of the relay unit while the line and the telephone are connected. Network controller. 2. The terminal network control device according to claim 1, wherein the control unit comprises a microcomputer, and an output from the contact detection unit is connected to an interrupt input of the microcomputer. 3. The terminal network control device according to claim 1, wherein the contact state detection unit operates with power supplied from a telephone line. 4. The terminal network control device according to claim 1, wherein the control unit stops the communication operation by the communication processing unit when the contact state detection unit detects the connection state in a state where the relay unit is controlled to be in a disconnected state. 5. The terminal network control device according to claim 2, wherein the control unit periodically checks the output of the contact state detecting unit at a preset time interval, and operates the relay unit in the connected state when the contact is inverted.