JPS5963573A - Automatic fault analyzer by code system - Google Patents

Abstract

PURPOSE:To allow even an unskilled person to utilize a cause analyzing method by a probe efficiently without providing many error latches, etc., by using in combination a storage medium stored with a fault analyzing procedure and a tester under microcomputer control. CONSTITUTION:A floppy disk 1e is stored with contents similar to the maintenance manual of an objective device of maintenance, i.e. normal code values obtained from respective positions that the probe contacts in a fault-free state, the position relation of a faulty member discriminated from the condition of a fault and whether a signal obtained by the probe at every point shows normalcy or not, a list of members which become faulty possibly, etc. A tester body 1a advances a fault analysis according to the previously investigated procedure on incorporated MPU, RAM and ROM and the loaded disk 1e. In this case, an operator only brings the probe 1d into contact with specified positions 2e according to the display on a display device 1b requiring no consideration. Therefore, the operator needs no special training, etc., and maintains numbers of machines without expert knowledge and expericence.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an automatic failure analysis device H that allows even an unskilled person to easily track down and identify the cause of a failure in a digital electronic device within a narrow range.

[Prior art]

In this case, in devices with complicated circuits, such as computers, multiple means of maintaining and indicating the state at the time of failure were used to facilitate maintenance work. For example, the number of error latches installed is increasing.The method of analyzing the failure information obtained by such means and diagnosing the cause of the C failure has been effective to some extent. In order to perform an accurate diagnosis, detailed information regarding the failure is required.
Therefore, for example, the number of error latches installed increases, and the cost
In terms of cost, the impact is becoming impossible to ignore. Especially in the case of OA equipment, for example, where it is preferable to supply large quantities at relatively low prices, the upper price range is large (・problem). In order to deal with such problems, the electronic equipment to be maintained is almost always built-in, using the signal generation means including the MPU and the extra space in the ROM. generate a desired test digital signal arbitrarily (only a small number of targets are required), and collect the signal generated at each specific part of the malfunctioning equipment circuit to be maintained through the glove in response to the test signal; This is compressed to, for example, about 2 bytes while retaining the characteristics of the signal, and the result is a (sufficiently reliable) value that could be obtained in the same way if this circuit had not failed. Compare,
A failure analysis method based on a so-called code system has begun to be used, which determines that the cause of the failure is in the member existing at the boundary of the part where the comparison result changes from match to mismatch. Means for detecting and collecting errors, such as multiple error latches, are no longer required. Also, since there is no need for the cost of an error latch, it was conventionally possible to use an error latch (due to the lack of price constraints).
Previously, the cause of failure was determined for each C board, but with some time and effort, it is now possible to trace the failure all the way back to the LSI level, for example, by compressing the signals collected from each part into, for example, 2 bytes. After processing, 4
Since it is displayed as a code value at the time of failure consisting of a hexadecimal code of digits, it would be easy to compare this with the code value at normal time for the corresponding part when there is no failure.However, the problem with this method is that An IF! How to select an appropriate signal collection point for a certain number of failures to achieve efficiency (locating the cause of the failure).Although there are some basic principles, in reality, it is difficult to If you do not follow the procedures you have considered, you may end up wasting a lot of time.

Therefore, this method requires a failure investigation manual for each device to be maintained. However, this point also applies to the case where the cause of the failure is determined by collecting information on the state at the time of failure using a conventional error latch or the like. The more this manual is made in detail so that it can be easily understood even by inexperienced Nagisa, the more the number of pages will increase, and the more difficult it will be to find the desired location. It is easy to get confused when trying to find the cause of a failure while being chased.

[Purpose of the invention]

The purpose of the present invention is to provide a code that does not have the above-mentioned problems in the conventional case, does not include a large number of error latches, and allows even an inexperienced person to efficiently and uniformly use the cause analysis method by collecting signals at the time of failure using a probe. An object of the present invention is to provide an automatic failure analysis device using a method.

[Summary of the invention]

In order to achieve the above object, the present invention collects and processes the signals generated in each part corresponding to the test digital signal using a probe, and collects the results of the processing to collect and process the signals that are generated in each part corresponding to the test digital signal. A failure N'F analysis procedure (program) is memorized that uses the contents of the 1 manual for the specified target device to identify the cause of the failure at the boundary (part side) of their coincidence or mismatch. A storage medium such as a floppy disk is loaded into the tester, which is controlled by a microcomputer, and the operator inputs the failure status.
According to the failure analysis procedure, the operator first displays the part to be touched with the glove, and then compares the processed signal 41 of the signal collected by valve the probe from this display part with the corresponding expected result in the program, and sometimes In some cases, the cause of the failure can be displayed immediately, but in general, the most appropriate area to be contacted with the glove is selected and displayed in the program, or the operator is informed of the probe contact area. display.

The operator repeatedly touches a display area with a probe, and based on the result, the program selects the next probe contact area to be displayed repeatedly to identify the component causing the failure. Usually, the contents of the manual for each target device can be easily
Can be stored on floppy disks. In addition, this floppy disk can be created by using the equipment to be maintained after a failure, the keyboard (and manual for the equipment to be maintained) with this failure analysis equipment, and the automatic failure analysis equipment itself.

[Embodiments of the invention]

Fig. 1 shows an outline of an embodiment of the present invention, in which 1 is an automatic failure analysis device (tester), 1a is the tester body, lb is a display, IC is a keyboard, 1d is a probe, 1e is a floppy disk, and 2 is a tester. Equipment subject to inspection and maintenance, 2a is MPU
, 2b is a ROM containing a test signal generation program;
c is a test signal generation button, 2d is a component that constitutes the circuit and may cause a failure (for example, a PC board or an I
C), 2e is the part to which the probe is brought into contact, and 3 is the operator. The floppy disk 1e contains the same contents as the conventional maintenance manual for the equipment to be maintained, namely the normal code value that should be obtained when there is no failure from each part that should be contacted by the probe, the failure situation, and the part sampled by the probe. It stores information such as the faulty parts that are determined or selected based on the correctness of each signal, the relationship between the positions where the probe should be contacted (Fault Diagnosis II), the parts where the probe should be contacted, and a list of parts that may cause a failure. I have let you. The tester main body 1a has a built-in Mpu, 11. A.M.
rtoyt and the loaded floppy disk IC, proceed with the failure analysis in accordance with the previously considered procedure.
All you have to do is touch the 8 (the thought process is short). Therefore, the operator (maintenance ^) has a special n11 for the 8 model.
In short steps such as one practice, one maintenance person can repair many models in depth (・
It can be maintained even without basic knowledge or experience.

〔Effect of the invention〕

As explained above, according to the present invention, maintenance personnel can carry out maintenance work simply by loading a storage medium storing the failure analyzer IFj for the maintenance target (type 1) and thereafter acting according to the display on the device. On the other hand, it is also possible to avoid a situation where an excessive number of error latches or the like are unnecessarily attached to the tFJfi to be maintained, which causes a price increase.

[Brief explanation of drawings]

Figure WJ1 is a schematic suspension diagram of one embodiment of the present invention. J...Automatic failure jγr analyzer, 1a...Tester body, 1b...Diffusion l/ (% ld...Probe, 1e...Floppy disk, 2...Test maintenance pair 8! 4ξ position, 2d...The side of the part that forms the circuit and may cause a failure, 2e...The part that comes into contact with the glove. Substitute η1'' Patent attorney Takeo Agata 1￥1
Figure 2 (?b

Claims (1)

[Claims] Corresponding to the encoded test signal input, the code value at the time of failure obtained by applying predetermined processing to the signal collected via the probe from each specific part of the six failed circuits of the maintenance target equipment and the code value at the time of failure of the circuit When the code value is compared with the previously considered normal code value obtained in the same way for each part, and if the source part where the above-mentioned binary discrepancy occurs can be detected, the member in contact with this part is Based on a failure analysis method that determines that the cause of the failure is in Display, display of the failure-causing member determined from the result of comparing the code value at the time of failure obtained according to this display with the code value at the time of normality, or the appropriate part to which the probe should be contacted next in order to further investigate the cause of the failure. An automatic failure analysis device using a code system that is equipped with 5 means of displaying or repeating the line.