JP2984414B2 - Network controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic meter reading system using a plurality of calls, and more particularly to a terminal network controller (hereinafter, referred to as NCU) connected between a center and a terminal device.

[0002]

2. Description of the Related Art As an automatic meter reading system for gas, water, and electric power, a system using a no-ringing communication service is used. There is also a no-ringing communication service of a multiple call signaling system that can connect a plurality of terminal NCUs to one telephone line.

[0003] In the case of this multiple paging signal system, N
Since a plurality of CUs are connected to a line, it is necessary to assign and identify a call signal (hereinafter, referred to as an NRS signal) for each terminal NCU. As a method of setting the NRS signal type of the terminal NCU, there is the following method. (1) A dip switch mechanism (switch setting circuit) is provided, and setting is performed by switch setting. (2) An NRS signal type data area is provided as a part of the ROM data, and individual data is written before installation on site.

[0004]

However, these methods are:
It is necessary to prepare an NCU corresponding to each NRS signal type, and the system is complicated. In addition, since a setting mechanism must be provided in the apparatus, this causes a high cost.

An object of the present invention is to provide a network control apparatus capable of setting an NRS signal type with a simple configuration without requiring a setting mechanism such as a switch circuit.

[0006]

In order to achieve the above object, the present invention relates to a network control apparatus which is connected to a plurality of subscriber telephone lines and transmits data from a terminal device to a center by a call signal from the center. Detecting means for detecting a response signal of the terminal device transmitted by another network control device, timer means for measuring the time until the detecting means detects the response signal, and measuring the time by the timer means. Discriminating means for discriminating that the other network control device has not responded to the call signal; transmitting means for transmitting a response signal when the non-response state is detected by the discriminating means; output signal of the transmitting means And connection means for connecting the own network control device to the telephone line, and identification means for using the call signal as an identification signal of the own network control device.

[0007]

In such a configuration, the detecting means detects the response signal of the terminal device transmitted from the other network control device, and based on the detection time of the detecting means measured by the timer means, the determining means determines that the terminal device is in a non-response state. When it is determined that the network control device is connected to the telephone line by the connection means and the call signal is used as the identification signal of the own network control device by the identification means, a special setting means is used as a system. The NRS signal type of the terminal NCU can be determined without the provision.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, another NCU is added to the existing NCU circuit.
A case where a circuit is newly provided will be described.

FIG. 1 is a block diagram of a terminal NCU of the automatic meter reading system of the present invention. In FIG. 1, [1] is a CPU.
It is a circuit that performs a series of processes shown in FIG. The CPU circuit [1] has an area (RAM area) for storing NRS type setting data. [2] is NC
In the U circuit, when no ringing is called, polarity inversion is detected,
This circuit performs polarity recovery detection at the end of no-ringing communication. [3] is a receiving circuit that detects an NRS signal from the center input through the NCU circuit 2 and a response signal (hereinafter, referred to as an ANS signal) from a meter (not shown). [4] is a transmission circuit, which transmits an ANS signal. [5] is a modem circuit, which performs signal conversion suitable for transmission / reception of data communication. [6] is a timer circuit that measures the time from when the receiving circuit 3 receives the NRS signal to when it receives the ANS signal. [7] is a meter I / F circuit for performing data communication between the terminal NCU and the meter. Next, the operation will be described.

For example, in the configuration diagram of the automatic meter reading system shown in FIG. No. 1 NCU has already been set (NRS type has been set; setting signal 1). A case where a 2NCU is newly installed will be described.

First, from the center device, the No. A non-ringing call is made to the terminal NCU via a no-ringing trunk (hereinafter, referred to as NRT) using an NRS signal other than the NRS type of 1 NCU (for example, set signal 2). At this time, No. In the 1NCU, the received NRS signal (setting signal 2) does not match the setting data (setting signal 1). In T1), the ANS signal is not transmitted.

On the other hand, no. In 2NCU, AN at T1
When the S signal is detected, the communication is stopped. If it is detected that the ANS signal has not been transmitted from another NCU at the time T1, the ANS signal is transmitted at a time when a predetermined time has elapsed from the time T1 (hereinafter referred to as T2). When the NRT receives the ANS signal, the NRT communicates with the center device. 2NC
A line with U is established, and data communication is established (see FIG. 3). After the data communication state, the No. is set by the NRS type setting message from the center device. The NRS type of 2NCU is set, and the communication ends (see FIG. 4).

After this setting, no. 2NCU is No. The state becomes the same as that of the NCU No. 1 and the NRS reception signal is compared with the setting data, and the mode is determined as to whether or not ANS transmission is to be performed (communication mode by normal no ringing call). Here, the time of T1 and T2 is
This is a time set to an arbitrary time within the NRT ANS reception detection time (up to 3 seconds). In addition, NC for terminal
Even when U is further added, it can be easily performed by repeating the above procedure.

[0014]

As described above, the present invention relates to a network control apparatus which is connected to a plurality of subscriber telephone lines and transmits data from a terminal to a center by a call signal from the center. Detecting means for detecting a response signal of the terminal device to be transmitted, timer means for measuring a time until the detecting means detects the response signal, and the other network control device Determining means for determining that there is no response to the calling signal; transmitting means for transmitting a response signal when the non-response state is detected by the determining means; Since it is composed of connection means for connecting the network control device and identification means for making the call signal an identification signal of the own network control device, no special setting means is required. It can be obtained a network control device capable NRS signal type setting with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a terminal network control device of an automatic meter reading system of the present invention.

FIG. 2 is a configuration diagram of an automatic meter reading system of the present invention.

FIG. 3 is a flowchart showing the operation of the terminal network control device of FIG. 2;

FIG. 4 is a diagram showing a no-ringing call signal type setting procedure of the present invention.

[Explanation of symbols]

 1 ... CPU circuit, 2 ... NCU circuit, 3 ... Reception circuit

Claims (1)

(57) [Claims] 1. A network control device connected to a plurality of subscriber telephone lines and transmitting data from a terminal device to the center in response to a call signal from the center, wherein a response signal of the terminal device transmitted by another network control device. Detecting means, a timer means for measuring the time until the detecting means detects the response signal, and the other network control device is in no response to the paging signal by the time measured by the timer means Discriminating means for discriminating that there is, transmitting means for transmitting a response signal when a no-response state is detected by the discriminating means, and connecting means for connecting the own network control device to the telephone line based on the output signal of the transmitting means A network control device comprising: an identification unit that uses the call signal as an identification signal of the own network control device.