JPH0191555A - Call/interruption signal transmitter - Google Patents

Abstract

PURPOSE:To prevent the production of a data error caused by synchronizing step-out by arranging a scrambler circuit and a delay circuit to a data transmission side and providing a descrambler circuit and a timing extraction circuit to a data reception side. CONSTITUTION:A scrambler circuit 17 scrambling a transmitted data and a delay circuit retarding the output of a call/interruption switch and inhibiting tentatively the output of the circuit 17 and the transmission of a call/interruption signal are arranged to a data transmission side 1. Then a descrambler circuit 28 descrambling the scrambled data and a timing extraction circuit 29 extracting a timing signal from the scrambled data are arranged to a data reception side 2. Thus, timing information is superimposed to the transmission data by the scrambler circuit 17, reception information is obtained by the descrambler circuit 28 to prevent the data error due to the synchronizing step-out of the timing and the delay circuit 18 inhibits tentatively the sending of the output of the scrambler circuit 17 and the call/interruption signal, thereby allowing the data reception side 2 to identify the call.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a call/disconnection signal transmission device that transfers one call/disconnection signal in a data exchange system interconnecting a plurality of data terminal devices. It is something.

[Conventional technology]

FIG. 3 shows, for example, a conventional calling bone cutting signal transmission device shown in the specification and drawings attached to the application for patent application No. 1980. In FIG. 1, 1 is a data terminal device, 2 is a The line side circuits of each data exchanger are shown in FIG.

11 is a transmission data input terminal; 12 is an AND gate whose 10,000 input terminals are connected to the transmission data input terminal 11; 13 is a line driver that transmits the output of this AND gate 12 to the subscriber line 3; A Nante gate connected to the other input terminal of the AND gate 12, 15 a pulse generator for call/disconnection signals connected to the -10,000 input terminal of the Nante gate 14, and 16 the other input terminal of the Nante gate 14. It is a call origination/disconnection switch connected to
The data terminal device 1 includes these in its line side circuit.

Also, at 21 a line receiver connected to the subscriber line 3;
22, a received data output terminal connected to the line receiver 21; 23, a signal detection circuit connected to the line receiver 21, which detects only pulse waves of a sufficiently high frequency for transmission data transmission speed of call/disconnection signals; 24; 25 is a differential circuit that provides a reset signal to the signal detection circuit 23; 25 is a flip-flop whose input terminal receives the signal from the signal detection circuit 26; and the trigger terminal T receives the transmission speed timing pulse; 26 is the line 27 is an OR gate connected to the receiver 21 and input to the output of the pulse extinction monitoring circuit 26 or the power supply reset signal t-D7 lip 70 tube 25% set terminal 5; These are included in the line side circuit.

Fig. 4 is a time chart showing all the timings of each signal of the transmitting device for call/disconnection signals, in which fal indicates the transmission data to be transmitted, and bl indicates the bit timing of the transmission data to be transmitted. (c) rr, a call/disconnect signal using a pulse wave with a frequency sufficiently high compared to the transmission speed of the transmitted data, fd) μ in the same figure, to the subscriber line 6 where the call/disconnect signal and the transmitted data are combined. The transmitted signal and the state transition of call origination/disconnection are shown in FIG.

Next, the operation will be explained.

First, in Fig. 8g4, the input terminal 1 receives the transmission data of the data terminal device 1 (indicated by al) at the bit timing shown in Fig. 8g4.
1 and is input to the AND gate 12.

Here, a frame is connected to the 10,000 input terminal of the AND gate 12.
A call/disconnection signal shown as fcl in FIG. The input transmission data is outputted to the subscriber line B via the line driver 16 in the same format as it is.The data transmitted by the data exchange 2 is received by the line receiver 21, and the received data output terminal 22 is output to.

Next, the operation of calling and disconnecting will be explained. Call origination/disconnection signal detection is performed by stopping a pulse wave of a sufficiently high frequency for the transmission data transmission speed when making a call, and transmitting the pulse wave at the time of disconnection using the h5 method. controlled by switching. In other words, when the output of the Nantes gate 14 is set to 71' at all times with the call origination/disconnection switch 16 turned to the calling side (earth ``'0''),
' state, but the switch 16 is set to the cut-off side (+5V
When the signal falls to "l"), the output of the pulse generator 15 for the call/disconnect signal, which generates a pulse wave 7 with a frequency sufficiently higher than the transmission speed of the transmitted data, appears inverted. This situation is shown in FIG.
In FIG. 4, the signal is sent to the subscriber line 6 as a transmission signal indicated by (dl).

The ratio signal is sent to the subscriber line 6 and input to the line receiver 21 of the data exchange 2, and the line receiver 21 receives
The output is supplied to the received data output terminal 22 and also to the signal detection circuit 23 and pulse extinction monitoring circuit 26.

The call/disconnect signal is extracted from the signal received by the line receiver 21 in the following manner. That is, the signal detection circuit 23 is reset for each bit period based on the transmission speed timing input via the differentiating circuit 24, and counts the frequency of the signal received by the line receiver for each bit period.

The output of the signal detection circuit 26 detects a call/disconnection signal using a pulse wave with a repetition frequency that is sufficiently higher than that of the data signal, and becomes 1" (disconnection detection) only in the cold state, and the call origination (call/disconnection signal stop) and During data transmission, it is 10''. The D flip-flop 25 is a memory that stores the calling/disconnecting state of the data terminal device 10, and the transmission speed timing pulse is input to the trigger terminal T[, and the F call is sent to the output of the signal detection circuit 26 at a 1-bit period. /Memorizes the disconnection state.

Mayu, the set terminal s V of this D flip-flop 25
ci, the output of the power supply reset and pulse extinction monitoring circuit 26 is supplied via the OR gate 27t-, thereby causing the D71J block flop 25 to be amputation”
It is initialized to the side.

[Problem that the invention seeks to solve]

Since the conventional call/disconnection signal transmission device is configured as described above, there is no particular problem in sending and detecting one call/disconnection signal, but if the data being transferred contains a large number of When a series of signals occurs, it becomes easy to lose synchronization, which causes data errors, which is a problem.

This invention has been made to solve the above-mentioned problems, and provides a call/disconnection signal transmission device that can prevent synchronization even when the data being transferred contains a large number of consecutive identical signals. The purpose is to obtain.

[Elaborate means to solve problems]

A call/disconnection signal transmission device according to the present invention includes a scrambler circuit that scrambles transmission data.

A descrambler that descrambles the scrambled data by placing a delay circuit on the data transmission side that delays the output of the call/disconnect switch and temporarily prohibits the output of the scrambler circuit and the transmission of the call/disconnect signal. A timing extraction circuit for extracting a timing signal from scrambled data is placed on the data receiving side.

[Effect]

A call/disconnection signal transmission device according to the present invention.

A scrambler circuit superimposes timing information on transmission data, and a descrambler circuit descrambles this to obtain reception information, thereby preventing data errors caused by out-of-synchronization of V% timing, and
By temporarily inhibiting the output of the scrambler circuit and the transmission of the call origination/disconnection signal using the delay circuit, the data receiving side is made to identify the origination of the call.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. WX
In the figure, 1 is a data terminal device, 2 is a data exchange %3 is a subscriber line, 11 is a transmission data input terminal, 12 is an andgoo), 13t is an m-line driver, 14 is a Nantes gate, 15 is a pulse generator, 16 is a call-disconnection switch, 21 is a line receiver, 22 is a received data output terminal, 23 is a signal detection circuit, 24 is a differentiation circuit, 25 is a D flip-flop, 26 is a pulse extinction monitoring circuit, 27
This is an OR gate, which is denoted by the same reference numeral in FIG. 3, and is the same as or corresponds to the conventional one, so a detailed description thereof will be omitted. Further, 17 is a friend scrambler circuit arranged between the transmission data input terminal 11 and the AND gate 12 of the data terminal device 1 and superimposes timing information on the transmission data; It is a delay circuit which is connected to the line receiver 21 of the data exchanger 2 and the received data output terminal 22 and is connected to the AND gate 12 together with the outputs of the Nant gate 14 and the scrambler circuit 17. A descrambler circuit is arranged between the 2S line receiver 21 and extracts received data by descrambles the scrambled data, and a timing extraction circuit is connected to the 2S line receiver 21 and extracts a timing signal from the scrambled t data.

FIG. 2 is a time chart showing the timing of each signal of such a call/disconnection signal transmission device.
Transmission data, (b) [The bit timing of the transmission data, the diagram (cl t1 call/disconnection signal, the signal sent to subscriber line 3 at +dl, the diagram +8] shows the call origination/disconnection signal. State transition, (gl in the same figure) is scrambled transmission data, (gl is the output signal of the delay circuit 18, (h) in the same figure)
The H-descrambled received data and the bit timing extracted from the received data are shown in (i) of the same figure.

Next, the operation will be explained.

First, as shown in FIG. 2 (al), transmission data from the data terminal device 1 is sent to the input terminal 1 at the bit timing shown in FIG. 2(b).
1 to the scrambler circuit 17 and is shown in FIG.
It is converted into scrambled transmission data shown in . Even if this scrambled transmission data has many consecutive @1'' or O'' signals, as in the transmission data shown in (a) in the figure, they are inverted depending on the bit timing, and there is no modification to this. This makes it easier to extract the bit timing in the data converter.

This scrambled friend transmission data is first input to the AND gate 12. Here, the call/disconnection signal shown in (C) in Figure 2 of the Nantes Gate 14 is input to the other two man-powered 10,000 units of the AND Gate, and during the call state,
The operation of the call origination/disconnection switch 16 is fixed at ``1''. !!fc, and at 10,000, the call origination is delayed by 1 bit timing by the delay circuit 18 shown in (g) in Fig. 2. - The signal from the disconnection switch 16 is input.This delay circuit [1811] When the call is made, the output of the AND gate 12 is set to '1' so that the call/disconnect signal and the scrambled transmission data are not passed. '' and notifies the data exchange 12 of the call. Therefore, the output signal of the scrambler circuit 17 is outputted to the subscriber line 3 via the line driver 13 in the same format except when this call is made. With data exchanger 2,
The transmitted friend data is received by the line receiver 21, and the received data is input to the descrambler circuit 28 in order to restore the original data, and is also input to the timing extraction circuit 29 at the same time. The received data is F-descrambled by the descrambler circuit 28 to restore the original data, and is output to the received data output terminal 22. The received data before being scrambled includes timing information (data change points), and the timing extraction circuit 29 can stably extract bit timing. This operation ensures synchronization between the data terminal device 1 and the data converter 2, and even if the 10'' or '1'' signals continue for a long time, there is no bit IA error due to synchronization deviation.

Further, since the call originating and disconnecting operations are the same as in the conventional case, the explanation will be omitted.

In the above embodiment, the case where the frame 1 call/disconnection signal is sent from the data terminal equipment side to the data exchange side has been explained, but conversely, the case where the disconnection signal is sent from the data exchange side to the data terminal equipment side is explained. It can also be applied to
it is obvious.

〔Effect of the invention〕

As described above, according to the present invention, a scrambler circuit and a delay circuit for delaying the output of the call/disconnect switch are arranged on the data transmitting side, and a descrambler circuit and a timing extraction circuit are arranged on the data receiving side. Now that you have configured the
Without complicating the circuit for transmitting and detecting disconnection signals, data errors due to synchronization deviations can be avoided even when the data being transferred contains a large number of consecutive '0's or frames '1's. It has the effect of preventing occurrence.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a call/disconnection signal transmission device according to an embodiment of the present invention, Fig. 2 is a time chart showing the timing of each signal, and Fig. 3 is a conventional call/disconnection signal transmission device. FIG. 4 is a block diagram showing the timing of each signal. 1 is a data terminal device, 2 is a data exchange, 16 is a call originating/
A disconnection switch, 17 a scrambler circuit, 18 a delay circuit, 28 a descrambler circuit, and 29 a timing extraction circuit. In addition, in FIG. 1, the same reference numerals indicate the same or equivalent parts. Patent applicant: Mitsubishi Electric Corporation (2 others)

Claims (1)

[Claims] A call/disconnection switch controls sending/stopping of a pulse wave with a frequency sufficiently higher than the data transmission speed transmitted between a data terminal device and a data exchanger, and a call/disconnection signal is generated depending on the presence or absence of the pulse wave. A call/disconnect signal transmission device that generates and transmits a signal includes a scrambler circuit that scrambles the data and superimposes timing information on the data transmitting side, and a scrambler circuit that is connected to the call/disconnect switch and outputs its output. A delay circuit is disposed to temporarily inhibit the output of the scrambler circuit and the transmission of the call/disconnect signal, and the scrambled data is descrambled to obtain received data on the data receiving side. A call/disconnection signal transmission device comprising a descrambler circuit and a timing extraction circuit for extracting a timing signal from the scrambled data.