JPH095400A - Electronic equipment - Google Patents

Abstract

PURPOSE: To provide an electronic equipment with a high reliability in use by accomplishing an inspection to determine whether a digital circuit of the electronic equipment operates normally or not easily and completely before the use of the equipment or at any desired time of a user. CONSTITUTION: Devices 3-11 necessary for accomplishing a boundary scan inspection designated as the standard of IEEE1149. 1-1990 are all built into electronic equipment (video camera body 13 in this example) so that the electronic equipment performs a self-diagnosing of its own digital circuit. An inspection starting switch 11 is interlocked to be closed when a power source switch 12 is closed to ensure that a boundary scan inspection is performed automatically when a power source is turned on. The boundary scan inspection is made possible time whenever necessary by single operation of the inspection starting switch 11 without regarding the power source switch 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to all electronic equipment using an integrated circuit having a boundary scan inspection device defined in the IEEE 1149.1-1990 standard. Is.

[0002]

2. Description of the Related Art A video camera, a still camera, etc., captures an unprecedented moment, or spends money and time to go to a location for shooting, so it is the worst situation that a failure is discovered when trying to use it. is there. The same applies to audio equipment at concerts. However, it is impossible to completely eradicate failures due to aging. This has been a serious problem for professional equipment such as broadcasting equipment and business equipment, which are not tolerated when used. In order to avoid this as much as possible, it is necessary to inspect the electronic device to be used at the time when the device can be repaired or replaced with a spare device should a failure occur. For this reason, conventionally, the user actually operates the functions of the electronic devices one by one to inspect for any abnormality. However, this requires labor and time, and the more multifunctional and more sophisticated the electronic device is, the heavier the load is. Moreover, it is difficult to completely cover a small malfunction in the electronic device. Further, as the digitization of video and audio signals progresses, there arises a problem that the least significant bit of the data line is missing. Problems due to this are difficult to find in normal use, but they are important for the quality of video and audio.

As a method of inspecting a defect in an electronic circuit, a boundary scan inspection defined by the IEEE1149.1-1990 standard is known. This is to provide an inspection device inside the digital integrated circuit, and to inspect the wiring of the digital circuit and the internal logic circuit of the digital integrated circuit on the mounting substrate using the inspection device. The boundary scan inspection will be described below with reference to FIG.

An integrated circuit 21 in which a boundary scan inspection device (not shown) is built in a substrate 22 in an electronic device 33.
Has been implemented. The electronic device 33 includes an inspector 3 including a group of devices for executing a boundary scan inspection.
Connect 4 Specifically, the inspection bus control device 23 for controlling the boundary scan inspection device is provided to the integrated circuit 21.
Are connected via four or five inspection buses 24.
The inspection bus control device 23 includes a first storage device 25 for holding an inspection signal input to the boundary scan inspection device,
And to a comparator 26 which compares the values of the signals.
The comparator 26 is connected to a second storage device 27 that holds an expected value of the boundary scan test and a diagnostic device 28 that diagnoses a defect. The diagnostic device 28 is connected to a display device 29 that visually displays the diagnostic result. Furthermore, the inspection bus control device 23, the comparator 26, the diagnosis device 28, and the display device 29 are connected to a main control device 30 that controls them, and the main control device 30 operates using the operation unit 31.

In the inspection, first, the inspection bus control device 23 puts the boundary scan inspection device in the integrated circuit 21 into the inspection state. Next, the inspection bus control device 23 reads the inspection input signal from the first storage device 25 and transmits it to the boundary scan inspection device. Inspection bus controller 23
The boundary scan inspection device controlled by the above performs inspection of the digital circuit, and the result is inspected by the inspection bus controller 2
Output to 3. The test result is transmitted to the comparator 26, where it is compared with the expected value of the test read from the second storage device 27. The comparison result is transmitted to the diagnostic device 28, where the defective condition, defective portion, etc. are diagnosed and displayed on the display device 29. Inspection bus control device 23, comparator 26, diagnostic device 2
8. The operation of the display device 29 is controlled by the main control device 30, and the operation of the main control device 30 is performed by the operation unit 31.

[0006]

However, the above-mentioned conventional boundary scan inspection is intended to detect a defect during manufacturing and to identify a defective portion during repair and repair. To perform this inspection, the above-mentioned method is used. As described above, it is necessary to externally connect the device for controlling the boundary scan inspection device built in the integrated circuit to the device under inspection. Therefore, it is impossible for the electronic device user to easily perform the boundary scan inspection.

The present invention is intended to solve the above-mentioned problems, and makes it possible to easily and completely inspect whether or not a digital circuit of an electronic device is normal before the electronic device is used or when a user desires, thereby making it reliable in use. An object is to provide an electronic device having high property.

[0008]

To this end, the electronic equipment of the present invention is provided with I
All the devices necessary for performing the boundary scan inspection defined as the EEE1149.1-1990 standard are built into the electronic device, and when the electronic device is turned on, the boundary scan inspection is automatically performed. When the power switch is closed, the boundary scan inspection start switch is also closed.

[0009]

Since all the devices necessary for performing the boundary scan inspection are built in the electronic device, the self-diagnosis of the digital circuit of itself can be performed without connecting any device from the outside. In addition, by interlocking the power switch and the boundary scan inspection start switch, the boundary scan inspection is automatically performed when the electronic device is turned on, and the boundary scan can be performed before using the electronic device without any special operation. Scan inspection can be performed.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG.
Here, a digital video camera for broadcasting is taken as an example.
An integrated circuit 1 incorporating a boundary scan inspection device (not shown) is mounted on a substrate 2, and an inspection bus control device 3 for controlling the boundary scan inspection device connects four or five inspection buses 4 to each other. It is connected to the integrated circuit 1 through. The inspection bus control device 3 is also connected to a first storage device 5 for holding an inspection signal input to the boundary scan inspection device, and a comparator 6 for comparing the values of the signals. The comparator 6 is connected to a second storage device 7 that holds the expected value of the boundary scan test and a diagnostic device 8 that diagnoses a defect. The diagnostic device 8 is connected to a display device 9 which visually displays the diagnostic result. Further, the inspection bus control device 3, the comparator 6, the diagnostic device 8, and the display device 9 are connected to a main control device 10 for controlling them, and the main control device 10 has an inspection start switch 11 for starting a boundary scan inspection. Connected. The inspection start switch 11 is connected to the power switch 12 of the video camera body.
All the devices described above are built in the video camera body 13.

In the inspection, first, the inspection bus control device 3 reads the inspection input signal from the first storage device 5 and transmits it to the boundary scan inspection device. The boundary scan inspection device controlled by the inspection bus control device 3 inspects the digital circuit and outputs the result to the inspection bus control device 3. The test result is transmitted to the comparator 6, where it is compared with the expected value of the test read from the second storage device 7. The comparison result is transmitted to the diagnostic device 8, where the defective condition, defective portion, etc. are diagnosed and displayed on the display device 9. Inspection bus control device 3, comparator 6, diagnostic device 8, display device 9
The operation of is controlled by main controller 10. When the power switch 12 of the video camera main body is closed, the inspection start switch 11 is also closed. Therefore, when the power is turned on, the boundary scan inspection is automatically performed. Further, by operating the inspection start switch 11, the boundary scan inspection can be performed at any time. The inspection start switch 11 is not provided, and the power switch 12 is the inspection start switch 1
Although it may be combined with 1, it is more effective because the boundary scan inspection can be performed without turning the power on and off by providing the inspection start switch 11 independently.

As described above, the user of the video camera can easily inspect the digital circuit before use or when desired, and the occurrence of accidental failure can be reduced. Further, since the digital circuit is inspected every time the power is turned on, it has the effect of periodical inspection. Since the boundary scan inspection can also identify a defective part, even if a failure is found, the manufacturer's service person can quickly repair it.

Although a digital video camera for broadcasting is taken as an example here, the present invention is IEEE1149.1-.
It is effective for all electronic devices using an integrated circuit having a boundary scan inspection device defined in the 1990 standard. In addition, 114 currently under discussion in IEEE
9.4 (Analog boundary scan inspection that extends the boundary scan inspection for digital circuit inspection to analog circuits and analog / digital mixed circuits) is standardized,
If implemented, it is possible to test most circuits in electronic equipment by using the present invention.

[0014]

Since the boundary scan inspection is automatically performed every time the electronic device is turned on, it is equivalent to the periodic inspection of the digital circuit, which leads to the improvement of reliability. Further, the electronic device user can perform the digital circuit inspection at any time by using the boundary scan inspection start switch, and high reliability can be obtained. Furthermore, since the digital circuit of the electronic device can be easily and completely inspected without a special inspection device, the probability of occurrence of a failure during the preparation or use of the electronic device is reduced. This test is also effective for faults that cannot normally be detected easily, such as digital bit loss. Further, since the boundary scan inspection can identify the defective portion, the serviceman of the manufacturer can promptly repair even if a failure is found.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an apparatus for performing a boundary scan inspection according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the configuration of a conventional apparatus for performing boundary scan inspection.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 integrated circuit 2 substrate 3 inspection bus control device 4 inspection bus 5 first storage device 6 comparator 7 second storage device 8 diagnostic device 9 display device 10 main control device 11 inspection start switch 12 power switch 13 video camera body

Claims (1)

[Claims] 1. An IEE (IEEE) 1
In an electronic device having an integrated circuit incorporating a boundary scan inspection device defined in the 149.1-1990 standard, a first storage device for holding a boundary scan inspection input signal, a boundary scan inspection signal and the boundary A control device for controlling the boundary scan inspection device to execute the boundary scan inspection, a second storage device for holding an expected value of the boundary scan inspection result of the integrated circuit, the expected value and the bound of the integrated circuit A comparison device that compares the results of the Dally scan inspection, a diagnosis device that diagnoses a circuit failure of the electronic device based on the comparison result of the comparison device, a display device that displays the diagnosis result of the diagnosis device, and the control device is activated. , A test start switch for starting a boundary scan test, and a power switch for the electronic device. When the closed from open, electronic apparatus, characterized in that to link to the examination start switch is from the open to the closed.