JP2837523B2 - Terminal network controller - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a terminal network control device, and more particularly to a terminal device that transmits a call request signal a plurality of times repeatedly when making a call request. The present invention also relates to a terminal network control device that can be connected via a communication line to a center device that sends necessary messages to the terminal device.

2. Description of the Related Art Conventionally, there has been known a data communication system for communicating information of devices such as meters and sensors to a center using a telephone line equipped with a no-ringing trunk.

FIG. 4 is a diagram showing a configuration of such a conventional data communication system. In FIG. 4, a center device 30 is connected to a host computer 31 via a connection line 33 and connected to the host computer 31 via a center-side network control device (C-NCU) 32.
And The center-side network controller 32 is connected to a center-side telephone exchange 41 via a telephone line 44.

On the other hand, the terminal device 50 is a terminal network control device (T-NCU) 5.
1 and a meter 52, a sensor 53, a recording terminal device 54, and a home telephone 55 connected to the terminal network control device via a connection line 56.
including. The terminal network controller 51 is connected to the terminal-side telephone exchange 42 via a telephone line 46. Terminal-side telephone exchange
Reference numeral 42 is connected to a no-ringing trunk 43 via interface lines 47 and 48. The terminal-side telephone exchange 42 and the center-side telephone exchange 41 are connected to each other via an interoffice trunk 45.

FIG. 5 is a diagram showing a sequence of a call request signal transmitted from the meter 52 or the sensor 53 shown in FIG. 4 to the terminal network control device 51. FIG. 6 is a diagram showing a sequence of messages exchanged between the terminal network control device 51 and the meter 52 or the sensor 53 when responding to the call request.

When a call request is issued from a device such as the meter 52 or the sensor 53 (hereinafter referred to as a device such as a meter) to the terminal network control device 51, an "H" level signal is output as a call request signal for T1 seconds, If there is no response from the terminal network control device 51, an "H" level signal is output for T1 seconds as a second call request after T2 seconds, and if there is no response, a third call request is further issued after T2 seconds. Do. In this way, three calling requests are made in T3 seconds. Note that T1 is about 1 second, T2 is about 5 seconds, and T3 is about 13 seconds.

Normally, as shown in FIG. 6, when confirming the first call request, the terminal network control device sends a downstream message (security request) to a device such as a meter, and transmits the message to the device such as a meter. When a response is received, the center is dialed, and after the line is connected, an upstream message is sent to the center. In FIG. 6, M means a mark (corresponding to a binary "1"), and S means a space (corresponding to a binary "0").

As shown in FIG. 6, when a downstream message is sent to a device such as a meter in response to the first call request, the device such as the meter requests a second or subsequent call request. Is not output.

By the way, the down message sent by the terminal network control device has a number called an entity code, and a device such as a meter always checks this number when exchanging the message, and the entity code checks the device code. If the code does not match the stored code, no response is made. Here, the business entity code is for identifying the business entity, and is, for example, "02" for an LP gas meter and "03" for a water meter.

In addition, the format of the downward telegram is also defined, and a device such as a meter does not respond unless a certain format is used. Therefore, in the terminal network control device, the business entity code of a device such as a meter and the format of a message to be transmitted are determined for each input / output port, and each port is connected only to a device such as a meter of a specific business entity. Like that.

[Problems to be Solved by the Invention] If each port of the terminal network control device is dedicated to a device such as each meter, each port can be connected only to a predetermined model. Therefore, it is not possible to connect two LP gas meters to a terminal network control device having one LP gas meter connection terminal.

In addition, since it is necessary to set identification information for identifying a device such as a meter to be connected to the input / output port in the network controller for the terminal, the trouble of setting is complicated, and a new message format is required. When it becomes necessary to connect a meter, there is a problem that the terminal network control device needs to be modified.

Therefore, an object of the present invention is to provide a terminal network control device capable of mediating communication between a device such as a meter and a center device regardless of the type of device such as a meter.

Means for Solving the Problems The present invention is connected to a terminal device that sends a call request and is connectable via a communication line to a center device that sends a necessary message to the terminal device. A network controller for dialing a center device in response to a call request, and a terminal to which a terminal device is connected when the center device is connected to a communication line in accordance with dialing by the dial device. Transmission means for transmitting the port number of the network control device to the center device, and transmitting from the center device to the terminal device a message conforming to the message format of the terminal device determined by the center device based on the port number. Is done.

[Operation] In the present invention, when there is a call request from one terminal device, the dialing means dials the center device. When the center device and the terminal network control device are connected via the communication line, the transmission means transmits to the center device the port number of the terminal network control device to which the terminal device requesting the call is connected. The center device retrieves a corresponding message from the file based on the port number and transmits the message to the terminal network control device. The transmission means of the terminal network control device transmits the message transmitted from the center device to the terminal device which has requested the call without checking the message. This allows
It is not necessary to set a predetermined message format in the terminal network controller, and any terminal equipment can be connected to the terminal network controller.

Embodiment of the Invention A data communication system to which an embodiment of the present invention is applied is the same as that shown in FIG. Although FIG. 4 shows a no-ringing system, the network control device for a terminal of the present invention is not limited to the no-ringing system, but can be applied to any communication system using a network control device. I will point out in advance.

FIG. 2 is a schematic block diagram showing the configuration of the terminal network control device according to one embodiment of the present invention. FIG. 3 is a schematic block diagram showing the configuration of the main control device shown in FIG. next,
With reference to FIGS. 2 and 3, the configuration of an embodiment of the present invention will be described.

The terminal network control device 1 is connected to a meter 3, a sensor 4, a recording terminal device 5, and a home telephone 6 via a connection line 2. The terminal network controller 1 is connected to a terminal-side exchange via a telephone line 7.

The terminal network controller 1 includes a main controller 10 and an oscillation circuit 11.
, A reset circuit 12, and interface circuits 13, 14
Power supply circuit 15, off-hook detection circuit 16, connection switching circuit 18, rectifier circuit 20, off-hook control circuit 22, PB
It includes a transmitting / receiving circuit 24 and a modem 26.

As shown in FIG. 3, the main controller 10 receives a CPU 101, a signal from an oscillation circuit 11 for generating a clock signal, and a timer counter 102 for measuring the time, a program memory 103 for storing an operation program of the CPU 101, and a main memory 10. It comprises a data memory 104 for temporarily storing data generated inside the control device, and an interface 105 for exchanging data signals between the main control device 10 and the outside.

The reset circuit 12 is for resetting the main controller 10. The power supply circuit 15 supplies power required for each electrical configuration of the terminal network control device 1.
The interface 13 mediates data communication between the meter 3 and the main controller 10, and the interface circuit 14 mediates data communication between the sensor 4 and the main controller 10. The off-hook detection circuit 16 detects whether or not the home telephone 6 is off-hook. The connection switching circuit 18 is for connecting or disconnecting the recording terminal device 5 and the home telephone 6 to the telephone line 7. The rectifier circuit 20, the off-hook rectifier circuit 22, and the PB transmission / reception circuit 24 transmit a selection signal for selecting the center-side network control device (C-NCU) to the telephone line 7.
Here, when the selection signal is a dial pulse, the main controller 10 generates a dial pulse by turning on and off the off-hook control circuit 22, and sends the selection signal to the telephone line 7 via the rectifier circuit 20 for adjusting the polarity. Send out. When the selection signal is a PB signal, main controller 10
The PB signal is generated by the control circuit 24 and the off-hook control circuit 22, and the selection signal is transmitted to the telephone line 7 through the rectifier circuit 20. The modem 26 is for performing data communication between the main controller 10 and the center device.

FIG. 1 is a flow chart for explaining the operation of an embodiment of the present invention. In particular, a call request procedure when a call request is issued from a device such as a meter, and a procedure for dialing a center. The procedure will be specifically described. The procedure of the call request is the same as the sequence shown in FIG. Next, the operation of the embodiment of the present invention will be described in detail.

In a case where a terminal call communication in which a call request is issued from the meter 3 or the sensor 4 is performed, when the call request is given to the main control device 10 via the interface circuit 13 or 14, the main control device 10 goes off-hook. The detection circuit 16 detects whether or not the home telephone 6 is off-hook. When on-hook, main controller 10 disconnects recording terminal 5 and home telephone 6 from telephone line 7 by connection switching circuit 18.

At t0 shown in FIG. 5, when the call request signal rises, main controller 10 cancels the standby in step S1, enters a timekeeping operation, and then waits for the fall of the call request signal. At t1 shown in FIG. 5, if there is a fall in the call request, the process proceeds from step S2 to step S3, and step S3
In the above, it is confirmed that the time T from the rise to the fall of the call request signal is Ta <T <Tb. If the time T does not satisfy this condition, since it is not a call request signal, error processing is performed in step S8, and the operation ends. On the other hand, if the time T satisfies the above condition, the operation for waiting for the termination of the transmission of the call request signal is started, ignoring the second and subsequent call request signals. Here, the reason for waiting until the transmission of the call request signal is completed is that when a call request is made from a plurality of devices such as meters in succession, the call requests from the plurality of devices are not confused.
This is to ensure that a call request from all devices that have issued the call request is received. Therefore, first, step
At S4, a time Tc (for example, 14 seconds) at which the call request can be ignored without fail is loaded into the timer counter T. continue,
In step S5, count down until T becomes zero.

If T becomes 0 in step S6, the calling operation from a device such as a meter ends, so the process proceeds to step S7 to shift to a dial operation for the center device. That is, the main controller 10 sends a selection signal for selecting the center-side network controller (C-NCU) from the off-hook control circuit 22 or the Pb transmission / reception circuit 24 to the telephone line 7 via the rectifier circuit 20. When the line link is established by the selection signal and connected to the center device, data communication is started between the terminal network control device 1 and the center device in a start-stop synchronous manner via the modem 26.

At this time, the main control device 10 sends the ID of the terminal network control device 1
The number and the caller port number are sent to the center device. Based on the ID number sent from the terminal network controller and the caller port number, the host computer of the center device searches the center device file for the type of the terminal device requesting the call, and responds to the device. And edits the downstream message including the business entity code to be executed and conforming to a predetermined message format, and sends the edited message to a device such as a meter. The terminal network control device 1 sends the downstream telegram to the meter 3 or the sensor 4 that has sent the call without checking the content of the telegram.

In this way, there is no need to set a predetermined message format in the terminal network controller, and communication between the meter or other device and the terminal network controller is independent of the type of device such as the meter. It is possible to do.

Also, even if a meter with a different message format is developed in the future, it can be connected to the terminal network control device,
Since there is no need to change the network control device, an economical communication system can be constructed.

[Effects of the Invention] As described above, according to the present invention, it is not necessary to set the message format of the terminal device in the terminal network control device. It is possible to provide a very useful and highly versatile terminal network control device, which can be connected to a network controller and sensors. Also,
Even if meters with different message formats are realized in the future,
Since it is possible to respond, it is possible to construct a communication system which is economically excellent.

[Brief description of the drawings]

FIG. 1 is a flowchart for explaining the operation of one embodiment of the present invention. FIG. 2 is a schematic block diagram showing the configuration of the terminal network control device according to one embodiment of the present invention. FIG. 3 is a schematic block diagram showing the configuration of the main control device shown in FIG. FIG. 4 is a schematic block diagram showing a configuration of a data communication system conventionally used and applied to the present invention. FIG. 5 is a diagram showing a sequence of a call request signal sent from a meter or a sensor used in a conventional communication system and a communication system applied to the present invention to a terminal network control device. FIG. 6 is a diagram showing a sequence of messages exchanged between a meter or sensor and a terminal network control device in a conventional data communication system. In the figure, 1 is a terminal network controller, 3 is a meter, 4 is a sensor, 7 is a telephone line, 10 is a main controller, 11 is an oscillator circuit, 13 and 14 are interface circuits, 20 is a rectifier circuit, and 22 is off-hook. A control circuit, 24 is a PB transmission / reception circuit, 26 is a modem, 101 is a CPU, 102 is a timer counter, 103 is a program memory, 104 is a data memory, and 105 is an interface.

Claims (1)

(57) [Claims] 1. A terminal network control device which is connected to a terminal device for transmitting a call request and which can be connected via a communication line to a center device for transmitting a required message to said terminal device. Dial means for dialing the center device in response to the call request; and the terminal to which the terminal device is connected when the center device is connected to a communication line in response to dialing by the dial means. Transmitting the port number of the network control device to the center device, and transmitting from the center device to the terminal device a message matching the message format of the terminal device determined by the center device based on the port number. And a network controller for a terminal.