JPH01112851A - Data communication system - Google Patents

Abstract

PURPOSE:To extremely shorten system-down time by outputting a reset signal when the processor part of a data communication device of one side detects the abnormality of other party, and making the data communication device of other party detect this reset signal and reset its processor part. CONSTITUTION:When the abnormality (communication abnormality, communication stop, etc.) occurs in the data communication device 1 on account of a some cause, the processor part 5 of the data communication device 2 of other party of communication detects it, and instructs a reset signal transmission circuit 10 to transmit the reset signal. The reset signal transmission circuit 10 transmits the reset signal to the communication line 7B of a transmitting side. The reset signal detection circuit 9 of the data communication device 1 detects this reset signal from the communication line 7B of receiving side, and resets the processor part 3 immediately. Thus, the reset processor part 3 starts to operate normally, and the communication is started again. In the case that the abnormality is caused in the data communication device 2 side on account of a some cause, as well, the processor part 5 is due to be reset in nearly the same way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data communication system, and particularly to a data communication system that performs mutual transmission and reception.

[Conventional technology]

A conventional example of this type of data communication system is shown in FIG.

The conventional example shown in FIG. 2 shows a full-duplex communication system, that is, a communication system that can simultaneously communicate in both directions.

In FIG. 2, the data communication device 10 includes a processor section 3 consisting of a central processing unit and a file device (not shown), and a communication control section 4. Similarly, the data communication device 2 includes a processor section 5 and a communication control section 6.

In reality, a communication device such as an acoustic coupler or a modem is used as the communication control unit 4.6, and the processor units 3 and 5
The computer devices are connected to each other via communication lines 7A and 7B, and data is mutually sent and received.

In addition, in order to prevent abnormal operation (such as no response) due to runaway of the control program of the processor section 3.5, a monitoring timer (watch) is installed in the processor section 3.5 itself to monitor abnormalities.
dog, timer), and if an abnormality is detected,
A method used was to reset processors 3 and 5. That is, a method is used in which a timer is reset at regular intervals using a monitoring program or the like, and if this timer is not reset due to some kind of failure, an overflow occurs and the processor units 3 and 5 are reset by this alarm signal. was taken.

[Problem that the invention seeks to solve]

However, in the above conventional example, a situation may occur in which the processor 3 or 5 malfunctions and communication stops even though there is no abnormality as monitored by the monitoring timer, and in this case, the reset is automatically performed. Therefore, there is a drawback that the operator has to go to the installation location of the data communication device 1 or 2 and manually reset the processor section 3 or 5.

[Purpose of the invention]

An object of the present invention is to improve the disadvantages of the conventional example and provide a data communication method in which the processor section of a data communication device is automatically reset in the event of an abnormality such as communication abnormality or communication stoppage. .

[Means for solving problems]

According to the present invention, in a data communication system in which a set of data communication devices are connected through a communication line and mutually transmit and receive data, when the processor section of each data communication device detects an abnormality in the other party, A configuration is adopted in which a reset signal sending circuit that outputs a reset signal to the transmission line is provided, and a reset signal detection circuit that immediately resets the processor unit when a reset signal is detected from the reception line is provided. This is intended to achieve the objectives mentioned above.

[For production]

When the processor section of one data communication device detects an abnormality in the communication partner, a reset signal sending circuit outputs a reset signal to the transmission line according to an instruction from the processor section. This reset signal is detected by a reset signal detection circuit attached to the other data communication device that is the communication partner, and the processor section is reset. In this way,
When either data communication device detects an abnormality in the other party, the processor section of the other party is reset in a very short time.

[Embodiments of the invention]

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

Here, regarding the same components as the conventional example described above,
The same symbols will be used.

Is this embodiment of Fig. 1 a communication line? A pair of data communication devices 1 and 2 are connected by A and 7B.

One of them, W1 made by Data Communication Co., Ltd., has a processor section 3 consisting of a central processing unit and a file device (not shown) and a communication control section 4, as in the case of the conventional example described above. A reset signal sending circuit 8 is provided between the processor section 3 and the communication line 7A, which is a transmission line of the data communication device 1. This reset signal sending circuit 8 generates a reset signal (a signal having a signal pattern different in data format between the processor units 3 and 5 of a data communication device that performs data communication) in response to an instruction from the processor unit 3. It has a function of sending out a signal for resetting the data to the transmission line 7A.

Furthermore, a communication line 7B which is a receiving line of the data communication device 1
A reset signal detection circuit 9 is provided between the processor section 3 and the processor section 3.
is attached. This reset and signal detection circuit 9 is
It has a function of immediately resetting the processor unit 3 when a reset signal is detected from the receiving line 7B.

The other data communication device 2 is configured in substantially the same way as the one data communication device 1 (however, the transmitting and receiving sides of the communication line are switched).

Next, the overall operation of the above embodiment will be explained.

For example, the data communication device 1 may have an abnormality (
When a communication abnormality (9, communication stoppage, etc.) occurs, the processor unit 5 of the data communication device 2, which is the communication partner, senses this and instructs the reset signal sending circuit 10 to send a reset signal. The reset signal sending circuit 10 sends out a reset signal to the transmission side communication line 7B. The reset signal detection circuit 9 of the data communication device 1 detects this reset signal from the communication line 7B on the receiving side, and immediately resets the processor section 3. As a result, the reset processor section 3 begins to function normally, and communication is resumed.

Even if an abnormality occurs in the data communication device 2 for some reason, the processor section 5 is reset in substantially the same manner.

〔Effect of the invention〕

As explained above, according to the present invention, mutual communication devices that perform data communication include a reset signal sending circuit that sends a reset signal having a signal pattern different from the data format transmitted and received between the processor units to the transmission line, and a receiving circuit. Since it is equipped with a reset signal detection circuit that detects a reset signal from among the signals input from the line and immediately generates a reset signal for the processor section, if one of the communication devices has a communication error or communication stop. If this occurs, the other processor section senses this, and the reset signal sending circuit and reset signal detection circuit function to reset the processor section of the communication device in which the abnormality has occurred, significantly reducing system down time. Furthermore, since the processor is automatically reset, it is possible to provide an unprecedented and excellent data communication system in which the number of maintenance steps can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a descriptive diagram showing a conventional example. 1.2...Data communication device, 3,5...
・Processor section, 7A, 7B...Communication line, 8
, 10... Reset signal sending circuit, 9, 11...
...Reset signal detection circuit.

Claims (1)

[Claims] (1) In a data communication system in which a set of data communication devices are connected through a communication line and mutually transmit and receive data, when the processor section of the data communication device detects an abnormality in the other data communication device, A data communication system comprising: a reset signal sending circuit that outputs a reset signal to the transmission line; and a reset signal detection circuit that immediately resets the processor unit when a reset signal is detected from the reception line. .