JPH022242A - Monitoring device - Google Patents

Abstract

PURPOSE:To easily and quickly detect and analyze a fault of a single loop subscriber line by providing a voltage detection means in addition to a current detection means as a reception means, a demultiplex means demultiplexing a transmission data based on the output signal and a collision detection means detecting collision. CONSTITUTION:A collision detection circuit 54 detects it as collision when waveforms of output signals of a current detection circuit 521 and a voltage detection circuit 522 differ from each other. Thus, when it is detected through an EXOR 541 via an AND gate 542, the case with the transmission of the subscriber is avoided and since the detection time differs from the current and the voltage, a collision detection flag (CO) is set through a timer 543 so as to give discrimination after a prescribed time elapses. Since the current detection circuit 521, the voltage detection circuit 522, the demultiplex circuit 53 and the collision detection circuit 54 are provided in this way, the transmission data of the subscriber side or the exchange side is monitored while being demultiplexed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a monitoring device for monitoring a single-current loop subscriber line accommodated in an exchange.

(Prior Art) FIG. 3 is a connection diagram of a conventional single-current loop subscriber line monitoring device. As shown in the figure, in the exchange, a level converter 1 of the exchange and a telex device 2 on the subscriber side are connected to a single current loop subscriber line (hereinafter simply referred to as a line) 3.
Connected with Level converter 1 is ±50v, ±20
It interfaces the mA line 3 and the exchange, and connects the reverse circuit (IIEV) II and the transmitter/receiver circuit (SD, R
D) 12, the 6° telex device 2 includes a receiver 21, a transmitting contact 22, etc. Test ammunition device 4 is on line 3.
is inserted, and the plug 51 of the monitor device 5 is inserted (fitted) into either of the plugs 41, 42 of the test ammunition device 4. The monitor device 5 includes a receiving circuit 52 that detects current. Such a monitor device 5 detects the current transmitted by the receiving circuit 52 to transmit data transmitted due to the disconnection of the transmitting contact 22 of the telex device 2 or the transmitted data due to the disconnection of the transmitting/receiving circuit 12 of the level converter 1 of the exchange, to the line 3.
is being monitored.

(Problem to be Solved by the Invention) However, the monitor device with the above configuration cannot distinguish between data sent from the subscriber side and data sent from the exchange side, and when garbled characters occur, it may be due to a collision or There was a problem in that it was not possible to determine whether the problem was due to a disability, etc.

The tree invention eliminates the above-mentioned problems and saves the data transmitted from the subscriber side and the data transmitted from the exchange side separately,
It is an object of the present invention to provide a monitoring device capable of detecting a collision.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a monitor device for monitoring a single-current loop subscriber line housed in an exchange, in which the current of the single-current loop subscriber line is a receiving means comprising a current detecting means for detecting and outputting a detection result, a voltage detecting means for detecting the voltage of the line and outputting a detection result; separating means for separating the output signal of the means into subscriber side data and exchange side data; and collision detecting means for detecting a collision of transmitted data based on whether the output signals of the current detecting means and the voltage detecting means match. It is equipped with.

(Operation) The technical means of the present invention operates as follows. Separation means (
For example, when receiving intermittent transmission data from the subscriber side, the line voltage does not change and the output signal of the voltage detection means (for example, the voltage detection circuit described below) remains constant. Therefore, it functions to output the output signal of the current detection means (for example, a current detection circuit to be described later) as output data on the subscriber side. Furthermore, when receiving intermittent transmission data from the exchange side, the line voltage changes and the output signal of the voltage detection means changes accordingly, so the separation means detects the output signal of the current detection means. It works to output as transmission data from the exchange. The collision detection means (for example, a collision detection circuit described later) determines that the output signals of the current detection means and the voltage detection means are normal when they match, and when they do not match, it is determined that there is a collision and outputs a signal indicating collision detection. In this way, as a receiving means, in addition to the current detecting means, a voltage detecting means is provided, and a separating means for separating transmitted data based on these output signals and a collision detecting means for detecting a collision are provided. Therefore, the problems of the prior art described above can be solved.

(Embodiment) Fig. 1 is an equivalent circuit diagram showing an embodiment of the present invention, and shows a monitoring state when the subscriber side and the exchange side have completed connection and no communication is taking place (idle state). This is what is shown. In this figure, the same reference numerals as in FIG. 3 indicate the same components. Also, in this embodiment, using the test ammunition device 4, the monitor device 5a is connected to the line 3 by fitting the plug 51 of the monitor device 5a into its connector 41, 42 in the same manner as shown in FIG. In the figure, they are omitted to simplify the explanation. The monitor device 5a of this embodiment has a receiving circuit 5 in addition to the plug 51 as in the conventional case.
2a, a separation circuit 53 and a collision detection circuit 54. The receiving circuit 52a detects the current of the line 3 and receives the detection result (T
In addition to the current detection circuit 521 that outputs the voltage (TL level), a voltage detection circuit 522 that detects the voltage of the line 3 and outputs the detection result (TTL level) is provided. The separation circuit 53 consists of AND gates 531, 532 and a mono multivibrator (M/M) 533, and based on the output signal of the voltage detection circuit 522, divides the output signal of the current detection circuit 522 into subscriber side data (SOB). It is separated from the exchange side data (EX). The collision detection circuit 54 includes an exclusive OR gate (
EXOR) 541, an AND gate 542, and a timer 543, and detects a collision of transmitted data based on coincidence/mismatch of the output signals of the current detection circuit 521 and the voltage detection circuit 522. Figure 2 (a), (b).

(C) shows the current, voltage, and T of each part of the circuit in Figure 1 during transmission on the subscriber side, transmission on the exchange side, and at the time of collision, respectively.
It is a signal diagram of TL level.

Next, the operation of this embodiment will be explained.

First, the case of receiving (monitoring) transmission data from the subscriber side will be described.

When the telex device 1 on the subscriber side starts transmission, transmission data is sent to the line 3 by disconnecting the transmission contact 22. When the loop current of line 3 is disconnected, the current detection circuit 52
1 detects 0 ampere, and +50V is constantly applied to the voltage detection circuit 522 from the level converter 1. As a result, the output signal of the voltage detection circuit 522 is "H" and does not change, so the output signal (VL) of the M/1ie 533 is always "L" (see FIG. 2(a)). Therefore M/M 5
33 is "L", the AND gate 531 is open (enabled) and the AND gate 532 is closed, so that the data transmitted by the transmission contact 22 is detected by the current detection circuit 521 and converted to a TTL level, and then The data is output from the AND gate 531 as subscriber side data (SOB).

Next, the case of receiving transmission data from the exchange side will be described.

When the exchange side starts transmission, the transmitting/receiving circuit 12 of the level converter 1 sends out transmission data to the line 3 intermittently. When the transmitter/receiver circuit 12 changes from +50V to -50V, the voltage detection circuit 522 detects this, converts it to a TTL level, and sends it to the M/M 5:33 of the separation circuit 53.

As a result, M/M533 is 150m5 for one character.
(However, in the case of 50 baud), the output signal is
(see FIG. 2(b)). Therefore, the AND gate 531 is closed and the AND gate 532 is opened. Therefore, the current detection circuit 521 outputs the transmitted data due to the intermittent operation of the transmitter/receiver circuit 12 at +20 mA.

If it is detected as OA intermittent data, it is converted to TTL level and outputted as exchange side data (EX) via AND gate 532.

Next, we will describe the operation when transmission data collides. The collision detection circuit 54 includes a current detection circuit 521 and a voltage detection circuit 5.
When the waveforms of the output signals of 22 are different, it is detected as a collision. Therefore, after detecting this through EXOR541,
By passing through the AND gate 542, the case of transmission from the subscriber side (Fig. 2 (a)) is avoided, and furthermore, as shown in Fig. 2 (C), since the detection time is different for current and voltage, the detection time is different. A collision detection flag (CO) is raised through a timer 543 so that a collision is determined after a certain period of time has elapsed.

As described above, according to this embodiment, the current detection circuit 521,
Voltage detection circuit 522, separation circuit 53 and collision detection circuit 5
4, it is possible to separately monitor the transmitted data from the subscriber side or the exchange side.

For this reason, it is possible to immediately determine whether the transcribing is on the subscriber side or the exchange side, or whether there is a conflict, making it easier to handle complaints about line 3, etc. Furthermore, since separate data can be recorded, the monitor contents can be easily read and work efficiency can be expected to increase.

(Effects of the Invention) As described above in detail, according to the present invention, voltage detection means is provided in addition to current detection means as the reception means, and separation means and collision detection means for separating transmitted data based on the output signals of these means are provided. Since a collision detection means for detecting is provided, it is possible to easily determine whether transmitted data is from the subscriber side or from the exchange side, and collisions in transmitted data can also be reliably detected. Therefore, it is possible to easily and quickly detect and analyze failures in single-current loop subscriber lines.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a monitor device showing an embodiment of the present invention;
2(a), 2(b), and 2(c) are signal diagrams of the embodiment of FIG. 1, and FIG. 3 is a connection diagram of a conventional monitor device. 1--Level converter, 2--111 telex device, 3-111 line, 4--1 test ammunition device, 5a--monitor device, 11--reverse circuit, 12 --- one transmitting and receiving circuit, 21 --- one receiver, 22- one -- transmitting contact, 41.42 --- connector, 51 --- plug, 52a --- one receiving circuit, 53 --- -One separation circuit, 54---One collision detection circuit, 521---One current detection circuit, 522---One voltage detection circuit, 531, 532, 542---And gate, 53
:l ---- Mono multivibrator, 541 -
--One exclusive OR gate, 543---One timer.

Claims (1)

[Scope of Claims] A monitor device that monitors a single-current loop subscriber line housed in an exchange, comprising: current detection means for detecting a current in the single-current loop subscriber line and outputting a detection result; and a voltage detection means for detecting the voltage of the voltage and outputting the detection result, and separating the output signal of the current detection means into subscriber side data and exchange side data based on the output signal of the voltage detection means. and collision detection means for detecting a collision of transmitted data based on whether the output signals of the current detection means and the voltage detection means match.