JPS61290834A - Supervisory equipment for condition of transmission circuit - Google Patents

Abstract

PURPOSE:To eliminate necessity of processing for futile transmission and to improve performance by providing a terminal supervisory and controlling section having function to delimit the place of trouble, function to supervise the condition of operation of own terminal equipment and to restore automatically from the state of trouble, and function to make other terminal equipment recognize the state of connection of own terminal to transmission circuit. CONSTITUTION:Information transmitted through a transmission circuit 1 at the time of normal operation is taken in a transmitting and receiving section 5, and at the same time, and always supervised by a terminal supervisory and controlling section 4. On receiving report of occurrence of abnormality from a transmission and reception controlling section 3 or the transmitting and receiving section 5, the terminal supervisory and controlling section 4 operates a switching section 6 and separates the transmitting and receiving section 5 from a transmission circuit 1 to discriminated whether detected abnormality is caused by a failure of the transmission circuit 1 itself or information on the transmission circuit 1 is damaged due to malfunction of own terminal equipment 21 which is not checked by the terminal supervisory and controlling section 4. Accordingly, information is no more sent from the terminal equipment 21 to the transmission circuit 1. Therefore,the terminal supervisory and controlling section 4 supervises in the while whether information of the transmission circuit 1 is restored to normal state or not.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a transmission line monitoring device in a terminal device in an information transmission system. The present invention relates to a transmission line status monitoring device for an information transmission system suitable for limiting the location where a failure occurs.

[Background of the invention]

In an information transmission system consisting of only multiple terminal devices without a special dedicated monitoring device installed in the system, a faulty terminal device should be promptly removed to avoid affecting the transmission line and other terminal devices. must be disconnected from the transmission line.

In conventional equipment, as disclosed in Japanese Patent Application Laid-open No. 59-140752, the terminal device itself is disconnected from the transmission line based on the information determined by the transmitter/receiver #1 section, which enables prompt failure detection and troubleshooting of the faulty terminal device. Although a great effect could be expected in terms of disconnection from the transmission line, this monitoring device has the following problems.

(1) It is only possible to detect that a fault has occurred in the transmission line itself, and there is no effective means for detecting the location of the fault.

(2) Even if there is a terminal device that is disconnected from the transmission line due to a failure or other reason, other terminal devices do not have a means to recognize this.

(3) In the case of a program runaway in the processor of the transmission/reception control section, the device will fall into a state where it cannot self-disconnect, and there will be no means of recovery.

The configuration of a conventional device is shown in FIG. 2. In the conventional example,
In a system in which a plurality of terminal devices 21 to 2n are connected via a transmission line 1 and bidirectional information transmission is performed between each terminal device, each terminal device 21 (22 to 2n) controls information transmission and reception processing. Transmission/reception control unit 3. Transmitting/receiving section 5 for transmitting and receiving information. It is comprised of a switching section 6 that disconnects the transmission line 1 and the terminal device 21, and a display section 10 that displays a failure between the own terminal device and the transmission line.

[Object of the Invention] The purpose of the present invention is to enable a terminal device operator in each terminal device of an information transmission system to collect information on the connection status of other terminal devices and information for locating a failure location in the event of a failure in the transmission line itself. It is an object of the present invention to provide a transmission line status monitoring device for a terminal device that has excellent maintainability and reliability so that it can be recognized.

[Summary of the invention]

The first problem mentioned above is that when a fault occurs in the transmission line itself, it is impossible for the terminal equipment to detect the fault location. In a connected information transmission system, this is a serious problem from the viewpoint of system maintenance and maintainability, and depending on the use of the system, it may become a fatal problem. Therefore, it is necessary to avoid such a situation and enable early detection of failure points. Therefore, it would be better to provide a means for the receiving terminal device to monitor which terminal devices the information transfer is normal and which terminals/devices the information transmission is not normal. Even if only the transmitted information is monitored, it cannot be determined whether the abnormal information is due to a malfunction of the transmitting terminal device. Therefore, according to the present invention, information for detecting a transmission line fault is provided for this identification, and by monitoring this information, it becomes possible to estimate the location of the fault to a certain extent.

In addition, as mentioned in item 2 of the above problem, the problem that the separated terminal device cannot be recognized by other terminal devices is also caused by the fact that information is sent from other terminal devices to this separated terminal device. In this case, the transmission line will be occupied unnecessarily, leading to a decrease in line efficiency. In addition, this also creates a problem in terms of operability from the operator's point of view, as there is a waiting time, and such a situation should be avoided. For this purpose, it is necessary to transmit information indicating disconnection that can be monitored by other terminal devices, and from an economical point of view, it is difficult to transmit this information via a transmission line. desirable. Even with conventional devices, in the processing of the processor of the transmission/reception control section,
This can be achieved by sending disconnection information, then disconnecting, and then connecting and then sending connection information, but in this case, as mentioned in problem 3 above, transmission and reception may be delayed due to information that has already been received. When the program of the controller's processor goes out of control, the terminal device becomes inoperable, and it is unable to send out information indicating whether or not its own terminal device is connected, and it is impossible to recover. It becomes possible.

Therefore, according to the present invention, these problems can be solved by providing means for monitoring the connection status and operation status of the own terminal device in a part other than the transmission/reception control unit that performs information reception processing.

As described above, according to the present device, it is possible to solve the problems of the conventional device.

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

In this embodiment, the terminal device 21 includes a transmission/reception control section 3, a terminal monitoring control section 4. Transmitting/receiving section 5. Switching section 6. Status display section 7. Storage section 8. and a step 109 (it is conceivable to provide an input/output device in the terminal device depending on the purpose of the system, but this is not directly related to the present invention, and will be collectively referred to as step 10).

The operation when the terminal device 21 receives information from the other terminals 22 to 2n will be explained.O During normal operation, the information transmitted via the transmission line 1 is taken into the transmitting/receiving section 5. It is constantly monitored by the terminal monitoring control unit 4.

The information taken in by the transmitter/receiver 5 is subjected to reception processing by the transmitter/receiver controller 3, but if an abnormality is detected in this received information, the abnormality is detected by the transmitter/receiver 5. If so, the transmission/reception section 5 reports the abnormality detection to the terminal monitoring control section 4 in the form of an interrupt. Furthermore, if the transmission/reception control section 3 detects an abnormality, the transmission/reception control section 3 reports the detection of the abnormality to the terminal monitoring control section 4 in the form of an interrupt. The terminal monitoring control unit 4, which receives the abnormality report from the transmission/reception control unit 3 or the transmission/reception unit 5, checks whether the detected abnormality is due to a failure in the transmission line 1 itself, or whether the terminal monitoring and control unit 4 was unable to check. In order to determine whether the information on the transmission line 1 has been damaged due to a malfunction of the own terminal device 21, the switching section 6 is operated to disconnect the transmission/reception section 5 and the transmission line 1. As a result, the terminal device 21
Since no information is sent to the transmission line 1 from then on, the terminal monitoring control unit 4 monitors whether the information on the transmission line 1 returns to normal during this time. If the information on the transmission port @1 returns to normal after disconnecting the terminal device 21 from the transmission line 1, it is determined that the failure is due to a malfunction of the terminal device 21, and the terminal monitoring control unit 4 controls the transmission/reception control unit 6 and the transmission/reception control unit. After initializing the section 5, the switching section 6 switches the transmitting/receiving section 5.
and transmission line 1. Similarly, when an abnormality different from the information abnormality detected by the above-mentioned transmission/reception control unit 3 and transmission/reception unit 5, such as a hardware failure, is detected, the transmission/reception control unit 3 and the transmission/reception unit 5 will The transmitting/receiving section 5 and the transmission line 1 are disconnected and initialization processing is performed by disconnecting the transmitting/receiving section 5 and the transmission line 1. However, if the detected abnormality cannot be recovered by initialization, such as a hardware failure, the transmitting/receiving section 5 and the transmission line 1 are disconnected. Leave it as it is.

As described above, the terminal monitoring device 4 changes the connection state between the terminal device 21 and the transmission line 10 as necessary by monitoring the operating status of the transmission/reception control unit 3 and the transmission/reception unit 5, and also monitors changes in the connection state. It is transmitted via the transmission line 1 to other terminal devices 22 to 2n.

Conversely, since the other terminal devices 22 to 2n similarly send out their own connection states, the terminal monitoring control unit 4 monitors the connection states of the other terminal devices 22 to 2n.

Furthermore, the information transmitted from the other terminal devices 22 to 2n shall periodically include transmission line fault detection information determined in advance between the terminal devices in order to detect a fault in the transmission line 1 itself in addition to data. A failure in the transmission line itself is detected by comparing this transmission line failure detection information in the terminal monitoring control unit 4 to see if it is as predetermined. At this time, since the source of the transmission from the receiving terminal device 21 is known, the location where the failure has occurred can be limited to a specific range.

During the transmission operation, after confirming that transmission line 1 is empty, the data, destination, source, and transmission line failure detection information are sent out in combination, and the transmission line failure detection information at this time is transmitted to the self. By checking in the terminal monitoring control section 4 in the terminal device, it can be guaranteed that whenever there is an abnormality in the transmission line fault detection information in the receiving terminal device, it is always a fault in the transmission line itself.

As a result of the above operations, the connection status of all terminal devices including the terminal device itself to the transmission line 1 and the failure status of the transmission line itself are stored in the storage unit 3 and updated. The latest status is displayed on the display unit 7 as necessary.

According to this embodiment, the following effects are achieved.

(1) Maintenance and maintainability Since the connection status of other terminal devices can be displayed, maintenance personnel can recognize the faulty terminal device from any terminal device, and even if a fault occurs in the transmission line itself, the receiving side terminal Since this can be detected in the equipment and the location can be limited to a specific range, it is possible to reduce the down time of the terminal equipment and the system down time, and to realize an information transmission system that is easy to maintain and maintain. effective.

(2) Reliability Since the terminal device has a monitoring function, it can automatically recover from an inoperable state due to program runaway when the transmission/reception control unit is configured with a microprocessor.
The damaged terminal device is immediately disconnected from the transmission line and is not connected to the transmission line until the normal state is restored, so a failure of one terminal device can affect the entire system and cause it to go into an abnormal state. Since this can be avoided, a more reliable information transmission system than before can be realized.

〔Effect of the invention〕

According to the present invention, since it is possible to check whether the destination terminal device is connected to the transmission line before sending, unnecessary input operations are reduced, and the operator can check the connection status of the destination terminal device. Even if you try to send without checking, before starting the sending process, you can check based on the status of other terminal devices stored in your own terminal device, which eliminates unnecessary processing for sending and improves performance. do.

In addition, the number of lines occupied by unnecessary transmissions is reduced.
This has the effect of improving line efficiency and improving operability since rejection information can be quickly output when a transmission operation is performed to a disconnected terminal device.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional example.

Claims (1)

[Claims] Among systems in which a plurality of terminal devices are connected via a transmission line and bidirectional information transmission is performed between each terminal device, a transmission/reception control unit that controls information transmission/reception processing; a transmission/reception unit that transmits/receives information; In a terminal device consisting of a switching section that disconnects the transmission line from the terminal device, and a display section that displays a failure between the own terminal device and the transmission line, there is a function to monitor the connection status of other terminal devices with the transmission line, and when a transmission line failure occurs. A terminal that has a function to limit the failure point within a specific range, a function to monitor the operating status of the own terminal device and automatically recover from the failure state, and a function to make other terminal devices aware of the connection status of the own terminal with the transmission line. 1. A transmission line status monitoring device for an information transmission system, comprising a monitoring control section.