JPS59144240A - Method and device for detecting terminal fault of transmission system - Google Patents

Abstract

PURPOSE:To detect speedily a fault position of a terminal by inserting periodically a check frame for terminal fault detection between data frames to be transmitted, and transmitting a check signal fed from an output-side unit to a terminal equipment. CONSTITUTION:A transmission controller 1 and plural terminal controllers 2 are connected together through a transmission line 3. The controller 1 is timed to the respective controllers 2 to multiplex and transmit signals on time-division basis to input/output units 4A and 4B which input and output data to and from address-specified terminal equipments 5A and 5B. The check frame for terminal fault detection is inserted periodically between data frames to the multiplexed and transmitted and the check signal is transmitted from the side of the unit 4A. When the fault of the terminal is detected by this check signal, a fault warning device 6 sends a signal to a display device 7, which displays the address of the faulty terminal and its input or output side discriminately.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for detecting a failure in a terminal of a transmission system, and is capable of quickly detecting the occurrence of a failure in a terminal and the location where the failure occurs.

Conventionally, in this type of transmission system, malfunctions and failures of terminals have been detected by means such as integrity checks of transmission signals and signal comparison operations, but this alone has not been enough to detect malfunctions and failures of terminals that output data to the transmission system. Malfunctions and failures can be detected by the data signal, but no failure information on the data receiving side is detected. In addition, a method has been considered in which the receiving side sends out a response signal on top of the transmitted signal every time, but this poses the problem of lowering the transmission efficiency, and there has been a demand for the development of a new detection method.

This invention has been made in response to the above-mentioned problems, and will be described below based on the embodiments shown in the figures.

FIG. 1 shows the basic configuration of a transmission system according to the present invention, which includes one transmission control device 1 and a plurality of terminal control devices 2 and 2.
', 2''... are connected in a so-called multi-drop system via a transmission line 3.The transmission control device 1 connects input/output crab units 4A-B and terminal control devices 2, 2 to be connected.
It controls the transmission and reception of signals with the terminal control devices 2, 2', 2", etc., and time-divides the signals to each input/output J unit 4A-B to the terminal control devices 2, 2', 2", etc. It is multiplexed and transmitted. The terminal control devices 2, 2', 2'', etc. receive multiplexed signals from the transmission control device 1 and control the connected input/output units 4A-B. The only difference is that it does not have a bus output function, and the other functions and configurations are exactly the same, so they can be configured with almost the same specifications. It outputs a data signal to B or receives data from the terminal device 5A-B, and here, this input/output crab unit 4A-
Of the terminal devices 5A and 5A-B, 4A and 5A are output sides that receive signals from the transmission system, and 4B and 5B are input sides that send data to the transmission system. Further, the addresses of each of the units 4A-B are set so that the corresponding output side unit 4A and input side unit 4B, which are to exchange data signals, have the same address.

Note that this figure shows an example in which two input/output units (4A-B) are connected to each control device 1 and 2, but
However, the present invention is not limited to this, and it is possible to connect any number of units. 6, 6', 6... are each terminal control device 2, 2,
2'' - A failure alarm unit connected to the transmission control device 1, which reads failure data received, checked and output by the connected control device and outputs an alarm. 7 is the failure alarm unit. The alarm output is received by the display panel that displays the occurrence of a fault, and by any fault alarm unit 6, 6, 6 that performs fault management, i.e., the entire system at the installation location of any terminal control device and transmission control device. It is possible to check for failures.

FIG. 2 is a diagram showing an example of the configuration of the operation section of the display panel 7, which is composed of an address display section 10, an operation mode setting switch 11, an address setting switch 12, a unit setting switch 13, and a status display lamp 14. . To explain its operation, during normal transmission system operation, the mode switch 12 is set to AUT mode,
When a failure occurs, the address of the failed unit is displayed on the display section 10, and the display lamp 14 distinguishes whether the failed unit is on the input side or the output side by the combination of lamps or blinking state. Display separately. M.A.
In N mode, use the address setting switches INC (address +1 count) and DEC (-1 count) to set the address of the unit or node whose status you want to check on the display unit 10, and display the status of that unit or node on the display lamp. Display. That is, the RUN lamp is lit to indicate that it is in operation, the FAIL lamp to indicate a failure, and the ABST lamp to indicate that it is not energized.

UNIT mode is a mode in which the status of the unit is set in advance.For example, if you set the address for which the unit is not connected, and the address for the unit that is connected but not powered on, this setting can be made. This information is stored in the alarm unit 6 and compared with failure data from the system, making it possible to output a more accurate failure alarm. This U
To operate the NIT mode, set the address of the unit on the display section 10 using the address setting switch 12, and press the unit setting switch to enable energization (EXST) or AB without energization.
ST) and the final address of the operational unit (END)
Set.

FIG. 3 is a block diagram showing the configuration of the failure alarm unit, which is connected to each control device via an address bus 21 and a control bus 22, and includes a failure data writing circuit 23, an address switching circuit 24, a memory RAM 25, a microprocessor, and a failure alarm unit. 26, an input/output circuit 27, and a pack-in circuit 28. Note that, as shown in the figure, a unit to which the display panel 7 is connected will be described. First, when the control device to be connected receives a signal, the control bus 22
Failure data and address signals are input to the write circuit 23 and the address switching circuit 24 via the address bus 23, respectively, and the write circuit 23 is sent to the memory 25 designated by the switching circuit 24 and allocated for each address.Whether the write circuit 23 is normal or abnormal. Write the failure data. On the other hand, in the input/output circuit 29 connected to the display panel 7 by the connection cable 29, the UN
The information set in the IT mode is received and sent to the microprocessor 26, and the processor 26 writes it into the memory 25 based on this information. The information written to this memory from the other party is checked in the processor 26, and if a failure is confirmed, an alarm is issued from the input/output circuit 29, and the display panel 7 displays the address of the unit where the failure occurred, the input terminals of the unit, and the output. The side distinction is displayed. The backup circuit 28 is an auxiliary power supply circuit that prevents the memory from being cleared or processing from being interrupted in the event of a power outage or the like.

FIG. 4 is a flowchart showing the transmission process of the transmission control device 1 and the terminal control device 2 of this transmission system example, and an example of operation will be described below based on this flowchart.

FIG. 4(a) shows the flow of the transmission control device 1, which is initialized (1) at the same time as power is turned on and outputs a synchronization signal 5YNC (2).
), first output a check start bit (3) to notify the start of this routine to the check routine (4) that detects the energization state and failure of the output side unit 4A.
Migrate after doing this. Next, output the synchronization signal 5YNC again (
5) Next, in the check routine (4), output the final address (address with the largest number of addresses) ad(e) among the normal input/output crab units in the energized state detected in the check routine (4).
6) Below, the unit at the corresponding address counts the data bits that exchange data by dividing them into fixed time intervals (-1') (confirming the end of the 8L data transmission cycle (9)) The address and the transmitted/received data are loaded (7).Here, the only address given as a transmission signal is the final address ad(e), and the following description is given to each terminal control device 2 including this transmission control device 1. The data address is determined by counting (-1) from this final address ad(e) for each address, thereby reducing the time required to send address signals and improving transmission efficiency.Data transmitted in data bits Parity check (10) If there is an abnormality, abnormal data is written to the memory 25 of the failure alarm unit 6 connected to this device 1 (11), and if normal, the writing to this memory 25 is cleared (02). The abnormal data written in this parity check is written a number of times a as appropriate.
After the transportation verification has been carried out several times, if none of the transportation verifications are abnormal, an alarm is outputted from the failure alarm unit 6 (Q3).

After completing a series of data transmissions, check the progress of the timer counter Φ and if it has reached the set time l, proceed to (2) and operate from the check routine (3); if it has not reached (
5) and data transmission is repeated again.

FIG. 4(A) shows the flow of the terminal control device 2, which performs initial settings (21) at the same time as power is turned on and waits for input of a synchronization signal 5YNC (22). Next, detect the input of the check start bit C3) If there is an input, proceed to the check routine (2) in the same way as transmission control device 1. If there is no start bit input, address ad(e) from transmission control device 1 Load C5) and count the addresses (-) in the same way as device 1.
1) Load the address and the data to be transmitted (27) at 26L. At this time, the input/output crab unit 4 connected to each terminal control device 2 detects when the address counted by each device 2 matches its own address. Data is exchanged with .

The loaded data (G27) is subjected to a parity check (28) in the same way as the transmission control device 1, and if there is an abnormality, it is stored in memory and a warning is issued after continuous transmission (9).
If normal, the memory is cleared (31).

FIG. 5 is a flowchart of the check routine shown in FIGS. 4(a) and 4(b). In this check routine, the energization state and failure of the output side unit 4A which cannot be detected by the above parity check is checked. Each output side unit) 4A is configured to output a response signal onto the check pit assigned to the corresponding address in response to the output (3) of the check start bit if it is energized and in a normal state. First, the transmission control device 1 outputs the final address ad (71+ (address with the largest number of addresses) of the input/output units connected to each control device 1 and 2) (each 4DL terminal control device 2 loads this address (41) .Each output side unit 4A outputs a response signal if the transmitted address matches its own address and is in a normal state, and each control device loads this response signal (42) I and detects the presence or absence of a response. (If there is no response at 43L, the abnormal data will be stored in memory 2 of alarm unit 6.
5 (if there is a response of 4, the memo IJ-writing is cleared (45). The abnormal data written at this time is continuously sent and verified a number of times a as in the parity check). If there is no response each time, an alarm is output (47). In (48), the address where the response signal was first input is detected, and the address ad(
e) has been obtained. After the above series of operations, each control device 1.
2 counts the address ad(n) (-1) (49
L, end check (5) The same cycle is repeated and the presence or absence of a response signal at each address is detected.Here, the address given as a transmission signal is ad(n) as in the case of data transmission. Each of the control devices 1 and 2 recognizes the addresses of check pits that are continuous for count (-1) L from ad(n), thereby improving transmission efficiency.

FIG. 6 is a format diagram of the transmission performed by the above operation, and as shown in FIG. 6(a), the synchronization signal 5YN
Following C, a check frame CF is first transmitted to the check start pit O8, then a data frame DF is repeated, and then a check frame C is transmitted periodically.
F is inserted. Figure 6(b) shows data frame D.
As shown in F, only the address signal ad (e) is first given, and the thinking is to determine the data bit d corresponding to each address.
Only (e), d (/-1)... are transmitted continuously, and further, starting from the address ad(t) of the operable unit in the normal state detected by the check frame,
It is efficiently configured to exchange signals with only eight of the n set addresses. Also check frame CF
Also, as shown in Fig. 6(C), the address signal transmitted is only ad(?), and thereafter, check'/qu bits C(n), t(n-1), etc. corresponding to each address are successively transmitted. A response signal from the unit 4A at the address is sent onto each check pit.

This invention is constructed as described above, and since a check frame is periodically inserted between data frames, it is possible to transmit a check response signal from an output side unit, which is difficult to confirm on the output side. It is possible to accurately identify unit failures. Furthermore, since each control device is equipped with a failure alarm unit and is configured to output an alarm, it is possible to confirm failures in all units connected to each control device and take prompt action. Furthermore, a display panel connected to the failure alarm unit is provided to display the address of the unit in which the failure has occurred so that the location of the failure can be accurately recognized, and central management of the transmission system is possible at the installation location of this display panel.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram of an example of a transmission system according to the present invention. FIG. 2 is a configuration diagram of the operation section of the display panel. FIG. 3 is a block diagram showing the configuration of a failure alarm unit. FIGS. 4(a) and 4(b) are flowcharts of the transmission control device and the terminal control device. FIG. 5 is a flowchart of the check routine in FIG. 4. FIGS. 6(a), (b), and (C) are transmission format diagrams in this embodiment. 1 is a transmission control device, 2, 2, 2... is a terminal control device 3
4A and 4B are transmission lines, 4A and 4B are input and output crab units, 5A and 5B are terminal devices, 6, 6, 6... are failure alarm devices, and 7 is display panel. August 1958 Patent Application No. 19069 2, title of invention Terminal failure detection method and device in transmission system 3;
Relationship with the case of the person making the amendment Patent Applicant Address 1825 Oaza Amemiya, Koshoku City, Nagano Prefecture In column 5 of the brief explanation of the drawings in the specification, in column 5 of the brief description of the drawings in the specification flS14lS14, line 123, there is a ``Figure 6 (a)
), (b), and (c) are transmission format diagrams in this embodiment.

Claims (3)

[Claims] (1) In a transmission system that includes a transmission control device that controls transmission timing and a plurality of terminal control devices, and that cyclically transmits time-division multiplexed data signals via transmission lines, addresses are set for each terminal device. A control system is constructed by connecting the input/output unit that outputs or inputs data signals to the transmission control and terminal control equipment, and periodically inserts check frames for terminal failure detection between data frames that are multiplexed and transmitted. A terminal failure detection method in a transmission system characterized by transmitting a check signal from an output side unit to a terminal device among input and output crab units. (2) Each terminal control device and transmission control device is equipped with a failure alarm unit that outputs an alarm signal, detects a failure of the terminal by parity check in the data frame and check signal in the check frame, and outputs an alarm. A terminal failure detection method according to claim 1, characterized in that: (3) Provide a display panel for a failure display section that has at least a display function for displaying the address of a terminal that has caused a failure and an input function for setting the address of an operable terminal, and provide an optional terminal control device or transmission control A terminal failure detection device in a transmission system connected to a device failure alarm device.