JPS63125026A - Failure diagnosising system in multiplexing device - Google Patents

Abstract

PURPOSE:To diagnose the existence of failures in a system which leads to a data terminal in a short time without lowering an availability factor by transmitting and receiving test data for failure diagnosis with the data terminal which has no time division multiplexing data to be transmitted and received and comparing the transmitted data with the received data. CONSTITUTION:A multiplexing control part 21 inquires whether terminal interfaces 22A1-22An have the data which should be tranmitted or not through a test bus 25 and if they do not have the data the part 21 indicates the terminal interfaces to transmit the test data for the failure diagnosis. The terminal interfaces execute the transmission and reception of the test data through the test bus 25 and check the data. Thus, since the test data is transmitted and received by utilizing the idle time in one data frame so as to diangose the existence of failures on line, a special testing device need not to be prepared and the existence of failures can be diagnosed very easily in a short time without lowering the availability factor of the system.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a fault diagnosis method in a multiplexing device.

(Prior Art) Conventionally, data communication systems such as digital exchanges have used multiplexing devices that time-division multiplex data to be sent to and received from data terminals.

FIG. 5 is a block diagram showing a conventional general configuration of a data communication system using such a multiplexing device. A plurality of data terminals 3A1 to 3An and 3B1 to 3Bn are connected to each multiplexed wave @2A and 2B via cables 4A1 to 4An and 4B1 to 4Bn.

In this configuration, for example, if there is data to be transmitted from the data terminals 3A 1 to 3A+1 to any of the data terminals 381 to 3Bn, the multiplexer 2A transmits this data to one
A method of inserting into data slots corresponding to each data terminal 3A1 to 3An in a data frame, or a method of attaching identification information of the f-even terminal and inserting it into data slots for n channels in a first-packed format; etc., and transmits it to one of the multiplexing devices 2B via the transmission path 1. On the other hand, the multiplexer 2B that has received the time division multiplexed data decomposes the multiplexed data and sends the data to the data terminal corresponding to the data slot number.
Alternatively, it is distributed and supplied to data terminals corresponding to the identification information.

(Problem that the invention attempts to solve) However, in the above communication system.

For example, if communication between data terminals 3A 1 and 381 becomes impossible, conventionally, data terminals 3A 1 and 38
1 is separated from the multiplexing devices 2A and 2B, and a test device is connected in its place to send and receive test data and trace the faulty part. For this reason, there was a problem that it took a long time to localize the failure location, and that the operating rate decreased because the test was conducted offline with the data terminal disconnected.

An object of the present invention is to provide a fault diagnosis method for a multiplexing device that can diagnose the presence or absence of a fault in a short time and without reducing the operating rate.

[Structure of the Invention] (Means for Solving the Problem) The present invention detects the presence or absence of time-division multiplexed data to be sent to and received from each data terminal, and detects whether or not there is time-division multiplexed data to be sent to or received from a data terminal. Test data for fault diagnosis is sent and received between the terminal and the data terminal, and the presence or absence of a fault in the system leading to the data terminal is diagnosed by comparing the transmitted test data and the received test data.

(Operation) The multiplexing device detects the presence or absence of time-division multiplexed data to be sent to and received from the data terminal, and if there is no data to be sent or received, it sends or receives test data for fault diagnosis to and from the data terminal, Diagnose the presence or absence of a failure by comparing transmitted data and received data.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of a multiplexing device to which the present invention is applied.
0. Multiplexing control unit 21. Terminal interface 22A provided corresponding to each of data terminals 3A 1 to 3An
1 to 22An, and a control bus 23 that connects these parts. A data bus 24° and a test bus 25 are provided.

The multiplexing control section 20 performs overall control of the multiplexing VT arrangement, and the multiplexing control section 21 . Terminal interface 22
Control of A1 to 22An is performed through a control bus 23. The multiplexing control unit 21 has terminal interfaces 22A1 to 22A.
The data from n is time-division multiplexed through the data bus 24 and sent to the transmission line 1. Further, the time division multiplexed data received from the transmission path 1 is decomposed into data for each data terminal, and transmitted to a designated data terminal via the data bus 24 and the terminal interfaces 22A1 to 22An. In addition to such a data transmission/reception function, the multiplexing control unit 21 also controls the test bus 2 to check whether the terminal interfaces 22A1 to 22An have significant data to be transmitted.
5, and if it does not have it, it has the function of instructing the terminal interface to send test data for failure diagnosis.

The terminal interfaces 22A1 to 22An send and receive data to and from the data terminals 3A1 to 3An, and
It transmits and receives data to and from the multiplexing control unit 21. In addition, significant data is extracted from the data of the data terminals 3A 1 to 3An, and if no significant data is received from the multiplexing control unit 21, the data terminals 3A 1 to 3An are extracted from the data.
It has a function to insert a flag pattern). Furthermore, according to instructions from the multiplexing control section 21 through the test bus 25,
It has the function of sending and receiving test data and checking it.

FIG. 2 is a diagram showing the frame structure of time-division multiplexed data, in which the synchronization pattern (SYN) is 100°.
1. It consists of a common part consisting of a test slot number 102 and a data part 103 for n channels. A synchronization pattern (SYN) 100 is used to indicate the start of one frame and to establish synchronization. The communication instruction section 101 has a bit number n equal to the number of channels (in 8-bit units) of the data section 103, and has, for example, an address number i (i=1 to
When only the terminal interface n) performs communication, the i-th bit of the communication instruction unit 1o1 becomes "1" and the other bits become "0". Test slot number 102 is
It shows the address number of the terminal interface during test data transmission/reception, and is composed of address bits AO to An and a bit T indicating that a test is being performed. The data section 103 concatenates the data of the terminal interface of the address number which is set as bit data in the communication instruction section 101 in a first-justified format.

FIG. 3 shows the communication instruction section 101 when the address numbers of the terminal interfaces 22A1 to 22An are "0 to 8" and the number of channels of the data section 103 is "4". 3 is a diagram showing an example of a test slot number 102 and the contents of a data section 103. FIG. In this figure, 8 of the communication instruction section 101
Since the 2.83 bit is "1", this indicates that the data transmitted from the terminal interfaces with address numbers "2" and "3" are present. In addition, the address number of the terminal interface represented by 2 bits A O, A I, A of test slot number 102 is “○” (A O =
O, A I=OA 2=O), and the bit T indicating that the test is in progress is "1", so the test data of the terminal interface with address number "0" is stored in the data section 103. It shows that it has been inserted into.

In the data section 103, the address number is "2".

Transmission data (significant data) from the terminal interface with address number "3" and test data transmitted from the terminal interface with address number "0" are concatenated in a first-justified format, and the rest is unused (empty state).

FIG. 4 is a block diagram showing a more detailed configuration of the multiplexing control section 21, in which the receiving system from the transmission path 1 is connected to the transmission path interface 210. Frame decomposition unit 211, synchronization establishment unit 2
12. The time division multiplexed data received by the transmission line interface 210 is input to the frame disassembly section 211 and the synchronization establishment section 212, synchronization is established using the synchronization pattern 100, and the frame disassembly section 211 divides the data by channel. The configuration is such that the address number of the destination terminal interface is formed in the assignment table 213, and this address number and data for each channel are sent to the data bus 24.

On the other hand, the transmission system includes a transmission path interface 215° and a frame synthesis unit 216. Timing generation unit 217° test control unit 218. The test control unit 218 determines the presence or absence of significant data for the terminal interfaces 22A1 to 22An through the test bus 25, and if there is significant data, sends the significant data from the terminal interface via the data bus 24. Frame synthesis section 2
16, and based on the address number formed in the assignment table 219, the corresponding bit of the communication instruction section 101 is set to "1" and is sent to the transmission path 1 according to timing control.

In this case, as a result of determining the presence or absence of significant data, the test control unit 218 instructs the terminal interface that does not have significant data to transmit test data, and also instructs the frame synthesis unit 216 to set test slot number 10.
Instruct the setting of 2.

The test data thus transmitted from the terminal interface is connected to significant data and sent to the transmission line 1, as shown in FIG. Then, one of the multiplexing devices that received this test data via transmission line 1 detects that it is test data because bit T in test slot number 102 is "1", and Send the test data to the terminal interface at the address number indicated by bits AO, AI, A2.

Therefore, the terminal interface that receives the test data checks whether the bits of the test data have changed, and if it matches the standard test data, it is determined that there is no failure, and if it does not match, it is determined that there is some kind of failure. It is determined that this has occurred, and the maintenance staff is notified of this via a display, etc.

[Effects of the Invention] As is clear from the above description, according to the present invention, test data is transmitted and received using the free time slot in one data frame for transmitting and receiving data, and the presence or absence of a failure can be diagnosed online. Therefore, there is no need to prepare special test equipment, and the presence or absence of a failure can be diagnosed extremely easily in a short time and without reducing system availability.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a multiplexing device to which the present invention is applied, FIG. 2 is a frame configuration diagram of time-division multiplexed data, and FIG. 3 is a diagram showing a communication instruction section, test slot number, and data section. An explanatory diagram showing an example of the contents, FIG. 4 is the multiplexing 111
FIG. 5 is a general block diagram of a conventional data communication system having a multiplexing device. 1... Transmission line, 2.2A, 2B... Multiplexer, 3
A1-3An,...data terminal, 20...multiplexer W1fl113111 section, 21...multiplexer 11i
IJI section 11, 22A1 to 22An...terminal interface. Figure 1 Figure 3

Claims (1)

[Claims] Time-division multiplexed data is decomposed and distributed to a designated data terminal among a plurality of data terminals, and data from a plurality of data terminals is time-division multiplexed and sent to a transmission path. The multiplexing device detects the presence or absence of time-division multiplexed data to be sent to and received from each data terminal, and sends and receives test data for fault diagnosis to and from data terminals that do not have time-division multiplexed data to send and receive. A fault diagnosis method for a multiplexing device, characterized in that the presence or absence of a fault in a system leading to a data terminal is diagnosed by comparing transmitted test data and received test data.