JPH0258452A - Loop back test system - Google Patents

Abstract

PURPOSE:To decide a fault section with one test by inserting the decision result of an error detected with a device to a position allocated with the device among a loop back test data string simultaneously when the loop back is executed on each stage. CONSTITUTION:The loop back test data column generated in a tester is inputted from an IN 1, outputted from an OUT 2 to a next stage device side, a loop back condition control is detected by a detecting circuit 11, and it is controlled to the loop back condition. At such a time, the input test data string from the tester side is compared and collated with the input test data string looped back from the next stage device inputted from the IN 2 by a comparing circuit 12, and the presence and absence of the error is outputted. Simultaneously, the test data string from the tester side is selected by a selector circuit 13 looped back to the tester side, the decision result output of the presence and absence of the error in the comparing circuit 12 is inserted to the position allocated to the device among the test data string by an inserting circuit 14, and outputted to the tester side from the OUT 1. Thus, the fault section can be decided by a single test.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a loopback test method in multi-stage relay transmission.
In particular, the present invention relates to a loopback test method that makes it possible to determine a faulty section in one trial by inserting a determination result into a position assigned to the device in the test data string.

[Conventional technology]

Conventionally, when performing a loopback test on a multi-stage relay, it is common to perform the loopback test using a loopback pattern sequence unique to each stage.

[Problem to be solved by the invention]

However, the above-mentioned conventional loopback test method has a problem in that, in order to determine a faulty section, a test pattern must be prepared for each relay stage and the number of relay stages.

[Means to solve the problem]

In order to solve such problems, the foldback test method of the present invention includes a detection circuit that detects the loopback test control and controls it to the loopback state, and a detection circuit that detects the loopback test control and controls it to the loopback state, and a test data string input from the tester side and the input test data string from the next stage equipment side. There is a comparison circuit that compares and verifies the returned input test data string to determine whether there is an error, and if you want to be in a looped-back state, the data string from the next stage device is selected, but in the looped-back state, It has a selection circuit that selects and folds back the data string from the tester side, and an insertion circuit that inserts the determination result of the presence or absence of an error in the comparison circuit into the position allocated to the test data string in the test data string. It is characterized by:

[Effect]

Therefore, according to the present invention, by inserting the determination result into the position assigned to the device in question in the test data string, it becomes possible to determine the fault section in one trial.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

The drawing is a block diagram showing an embodiment of the folding test method according to the present invention. In the same figure, INI.

0UTI is the input/output on the tester side, IN2゜0UT
2 is the input/output of the next-stage device, respectively.

Further, 11 is a detection circuit that detects the loopback test control and controls the loopback state, and 12 is a detection circuit that compares and collates the input test data string from the tester side and the input test data string that has been looped back from the next stage device side. a comparison circuit for determining the presence or absence of an error; 13;
14 is a selection circuit which selects the data string from the next stage equipment side when it is not in the looping state, but selects and loops the data string from the tester side when it is in the looping state; 14 is the comparison circuit 1;
This is an insertion circuit that inserts the determination result of the presence or absence of an error in step 2 into the position assigned to the device in question in the test data string.

Next, the operation of the above embodiment will be explained. The return test data string generated by the tester is input from INI and output from OUT 2 to the next stage equipment side, and the detection circuit 11
Detects loopback control and controls the loopback state. At this time, the comparison circuit 12 compares the input test data string from the tester side with the input test data string input from IN2 and returned from the ninth stage device side, and outputs the presence or absence of an error. At the same time, the selection circuit 3 selects the test data string from the tester and returns it to the tester. Furthermore, the insertion circuit 4 inserts the output of the determination result of the presence or absence of an error in the comparison circuit 2 into the position assigned to the device in this test data string, and outputs it to the tester side from 0UTI.

Note that similar operations are performed in the next-stage device as well.

〔Effect of the invention〕

As explained above, the present invention executes loopback at each stage, and at the same time inserts the determination result of the presence or absence of an error detected by the device into the position assigned to the device in the looped test data string. This has the effect of making it possible to determine the faulty section in one trial.

[Brief explanation of the drawing]

The drawing is a block diagram showing one embodiment of the present invention. 11...detection circuit, 12...comparison circuit, 13...
...Selection circuit, 14...Insertion circuit.

Claims (1)

[Claims] A detection circuit that detects loopback test control and controls the loopback state compares the input test data string from the tester side with the input test data string looped back from the next stage equipment side to check for errors. A comparison circuit that makes the determination, a selection circuit that selects the data string from the next stage equipment side when it is not in the looping state, and a selection circuit that selects and loops back the data string from the tester side when it is in the looping state, and the comparison circuit. 1. An insertion circuit for inserting a determination result of the presence or absence of an error in a test data string at a position allocated to the device concerned.