JPH02266731A - Loopback test system - Google Patents

Abstract

PURPOSE:To easily detect at which side of transmission or a reception, the operation abnormality of a module occurs by comparing real data sandwiched between the start flags and end flags from plural modules. CONSTITUTION:A selector 5e selects a flag generating part 4 first to attach the start flag, and next, selects input data, and attaches the end flag by selecting the flag generating part 4 finally. For example, when loopback is performed after performing the processing of the module 2a, a selector 5a selects loopback data, and selectors 5b-5d select line data. The data is looped back, and is inputted to a data comparison part 3 at a point 6, and a real data sandwiched between the start flags and the flags from the plural modules 2a-2d are compared with each other. Thereby, it is possible to confirm the operation of each module from the real data, and to easily detect at which side of transmission or reception, the operation abnormality of the module exists.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a loopback test method in a data transmission device.

(Prior Art) In recent years, data transmission devices have become multifunctional and complex, and a loopback test function has become important for detecting an abnormal module when an abnormality occurs in the device.

FIG. 5 is a block diagram of a data transmission apparatus using a conventional loopback test method similar to that shown in, for example, Japanese Patent Application Laid-Open No. 63-39226.

In the figure, (1) is a data transmission device, (2a) to (2
d) is a functionally divided module, (4) is a flag generation unit that generates a start flag and an end flag indicating the beginning and end of test data, and (5a) to (5e) are selectors that switch data. (5a) - (5
d) switches between data received from the line side and loopback, and selector (5e) switches between manual data, test data, and flags.

(6) is a flag detection unit that detects the start flag and end flag; (8) is a comparison unit that compares the data between the start flag and the end flag with the test data; (9)
) is a test data generation unit that generates test data.

Next, the operation will be explained. Generally data transmission equipment (1
) performs predetermined processing on the input data and sends it to the line side as line output data, as shown in Figure 6, and also performs processing to restore the line input data from the line side and outputs it as output data. The processing performed within the data transmission device (1) that outputs the data is generally divided into modules for each function.

The configuration shown in FIG. 5 shows the case where the number of modules is 4, and the human data is first processed by the module (2d), and then processed by the module (2C). 2b), (2a
) is processed and sent to the line. In the case of reception from the line, the module (2a
), (2b), (2C), and (2d) are performed in this order.

The loopback test detects an abnormal module by looping back after each module has been processed and confirming whether the human input data is correctly output as output data.

FIG. 7 shows this loopback test procedure. For example, first, as shown in (a), after processing in module (2c), loopback is performed to compare output data and input data. If the comparison results are equal, it can be seen that the modules (2c) and (2d) are operating normally. Subsequently, (b), (C)
If the comparison results are not equal in case (C), it means that an abnormality is detected in module (2a).

Furthermore, to explain the specific operation, in FIG. 5, except during the loopback test, the selector (5e) always sends human data to the module (2d).
The data format is shown in FIG. 4(a).

During the loopback test, the selector (5e) first selects the flag generating section (4) to add a start flag indicating the start of transmitting test data. At this time, the flag generation section (4) selects the test data generation section (9) to add the test data generated from the test data generation section (9) to the 0th order that generates the start flag, and finally selects the test data generation section (9) to add the test data generated from the test data generation section (9). Select the flag generator (4). At this time, the flag generating section (4) generates an end flag. The data format at this time is shown in Figure 4 (C).

For example, when looping back after processing module (2C)'A, the selector (5C) selects loopback data, and the selector (5d) selects line data. The data is looped back by these selectors, and between the test data from when the flag detection section (6) detects the start flag to when the end flag is detected, the test data is specified to the comparison section (8) and the received data and the comparison section (8) are ) Compare internal test data.

[Problem to be solved by the invention]

The conventional loopback test method is performed as described above, so it is difficult to detect abnormalities because the comparison target data is known fixed test data, and even if an abnormal module is identified, The problem was that it was unclear which of the two was abnormal.

This invention was made to solve the above-mentioned problems. It is possible to check the operation of each module using actual data, and it also has a loopback function that allows it to easily detect whether an abnormality in module operation is on the transmitting side or the receiving side. The purpose is to obtain a test method.

[Means to solve the problem]

The loopback test method according to the present invention is a loopback test in which the operation of each module in a data transmission device constituted by a plurality of modules is looped back after processing each module to check whether input data is correctly output as output data. The method includes a flag detection unit that detects start and stop flags of human data at each point where data from multiple modules are compared, and a buffer that stores actual data between the start and stop flags. The data comparison unit includes a comparison unit that compares actual data sandwiched between start flags and finish flags from a plurality of modules.

[Effect]

The loopback test method according to the present invention mutually compares actual data sandwiched between start flags and end flags from a plurality of modules in a data transmission device.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figure explains the loopback test method of the present invention, and is a block diagram of a data transmission device (1) in which the same parts as in the conventional example shown in FIG. 5 are given the same reference numerals. In the figure, (3) indicates a data comparison section, and this data comparison section (3)
), as shown in FIG.
(6f), buffers (7a) to (7f) for once accumulating the data sandwiched between the start flag and end flag
) and a comparison section (8).

Next, the operation will be explained with reference to the loopback test procedure shown in FIG.

FIG. 3(a) shows the case of looping back after module (2a) processing and comparing data at six downward arrow points. From the left of the diagram, the six arrow points are: module (2a) after transmission processing, module (2a) after reception processing, module (2b) after reception processing, module (2c) after reception processing, module (2a) after reception processing,
d) After receiving processing and before transmitting processing of module (2d).

For example, if the data comparison result is that the two points on the left match the rightmost point, and the remaining three points match (for example, A, A, B, B, B from the left).

In the case of a pattern like A), it is determined that there is an abnormality on the receiving side of the module (2b).

Also, if the above comparison results match the 5 points on the left and only the remaining 1 point differs (for example, from the left, B, B, B,
B, B, A), it is determined that there is an abnormality on the transmitting side of one of the modules (2a) to (2d), so loopback is performed after filling the module (2bl) shown in Figure 3(b). It turns out.

If all data comparison results in the loopback in the module (2b) match, it is determined that there is an abnormality on the transmitting side of the module (2a). If everything doesn't match, for example B from the left.

If the pattern is B, B, B, A, the sending side of module (2a) is normal, but the module (2a) is normal.
Since it is determined that there is an abnormality in one of the transmitting sides of 2b) to (2d), the module shown in FIG. It's the same.

Next, specific operations in the configurations shown in FIG. 1 and FIG. 2 will be explained.

In FIG. 1, except during the loopback test, the selector (5e) selects human power data and always sends the human power data to the module (2d). At this time, the data format is as shown in FIG. 4(a).

During the loopback test, the selector (5e) first selects the flag generation unit (4) to add a start flag. At this time, the flag generation section (4) selects the input data to output the input data after generating the start flag, and finally selects the flag generation section (4). ) generates an end flag.The data format at this time is as shown in FIG. 4(b).

For example, when looping back after module (2a) processing, selector (5a) selects loopback data, selectors (5b) to (5d) select loopback data, and selectors (5b) to (5d) select loopback data. )
selects line data. The data is folded back by the aforementioned selector and input to the data comparison section (3) at the aforementioned six points. The data comparison unit (3) has a flag detection unit and a buffer for each of the six manual data, and the flag detection units (6a) to (6f) detect the start flag and then the end flag. Buffers (7a) to (7f) for the actual data up to
write to. In the comparison section (8), buffers (7a) to (7
f) Compare the actual data written to each other.

〔Effect of the invention〕

As described above, according to the present invention, the actual data sandwiched between the start flag and end flag from a plurality of modules are compared with each other, so the operation of each module can be confirmed using the actual data. In addition, there is an effect that it is possible to easily detect whether the malfunction of the module is on the transmitting side or on the receiving side.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a data transmission device using a loopback test method according to an embodiment of the present invention, Fig. 2 is a block diagram of a data comparison section, and Fig. 3 is a loop diagram illustrating the loopback test method of the present invention. 4 is a data format diagram, FIG. 5 is a block diagram of a data transmission device using the conventional loopback test method, FIG. 6 is an explanatory diagram of the conventional loopback test procedure, FIG. 7 is an explanatory diagram showing the human output of the data transmission device. In the figure, (1) is a data transmission device, (2a) to (2
d) is a module, (3) is a data comparison section, (4) is a flag generation section, (5a) to (5e) are selectors, (6a) is a
) to (6f) are flag detection units, (7a) to (7f) are buffers, (8) is a comparison unit, and (9) is a test data generation unit. In each figure, the same reference numerals indicate the same or corresponding parts. Agent: Masuo Oiwa (Voluntary)

Claims (1)

[Claims] In the loopback test method, the operation of each module in a data transmission device composed of multiple modules is checked by checking whether the input data is correctly output as output data by checking the operation of each module after processing each module. A data comparison device that includes a flag detection unit that detects start and stop flags of input data at each point to be compared, a buffer that stores actual data between the start and stop flags, and a comparison unit that compares the actual data. A loopback test method characterized by comparing actual data sandwiched between start flags and end flags from multiple modules.