JP5844245B2 - USB abnormality cause determination device and image processing device - Google Patents

Description

  The present invention relates to a USB abnormality cause determination device and an image processing device.

  In recent years, a USB (Universal Serial Bus) interface has been widely used as an interface for connecting an information processing terminal such as a personal computer and an external device such as a printer or a storage device. The connection between the information processing terminal and the external device is realized by connecting the USB port of the information processing terminal and the USB port of the external device with a USB cable that satisfies the USB standard.

  Such a connection can be made very easily without referring to a device manual. Therefore, even if there is a problem in communication between connected devices, the user often cannot find the cause. For example, when a USB hub is interposed in the connection path of the USB cable, the communication speed may decrease, and trouble may occur due to the decrease in the communication speed. In order to avoid such problems, Patent Document 1 described later determines whether or not a USB hub is connected to the USB cable. If the USB hub is connected, a warning image is displayed and the user is displayed. The technology to notify is disclosed.

  On the other hand, the USB interface is used not only for interconnection with external devices but also for data transmission / reception in a single device. For example, in a multi function peripheral (MFP) used in an office or the like, a circuit for realizing each function is formed over a plurality of substrates. For example, a substrate for image processing is a higher-level device (hereinafter referred to as a USB host), and another substrate for facsimile transmission / reception or a memory is defined as a lower-level device (hereinafter referred to as a USB device). Data transmission / reception is performed between each board and between each board and the memory. For such data transmission / reception, a USB high-speed transfer standard (for example, USB 2.0 standard) is used.

  In the USB 2.0 high-speed mode (HS mode), the USB host detects the connection state between the USB host and the USB device. The detection is so-called disconnection detection, in which one of the differential signals D + and D− of the USB interface is at a high level (high potential state) and the other is at a low level (low potential state). Whether the USB device is connected or not is determined based on the amplitude (differential voltage value).

JP 2006-285071 A

  However, as described above, when a USB connection is used for data transmission / reception within a single device, the connection may be realized by a USB cable. However, from the viewpoint of space saving, the USB cable is used instead of the USB cable. Connections are often made by the created wiring, and a unique structure is often adopted for the connection part between the substrates.

  In a multi-function peripheral employing such a configuration, the USB host (for example, an image processing board) and a USB device (for example, a facsimile transmission / reception board) are disconnected while the apparatus is in use. May be detected. In this case, since the USB host and the USB device remain connected, reconnection processing is performed at the USB interface. When such disconnection detection and reconnection processing occurs, data transmission / reception is not performed during that time, resulting in a decrease in communication speed and a decrease in device performance.

  However, in the current multifunction peripheral, a record in which a disconnection is detected remains in the USB connection, but it is difficult to find out the cause of the disconnection detection and reconnection process from only the record. Further, even if the technique disclosed in Patent Document 1 described above is applied, such a problem cannot be solved.

  The present invention has been made in view of such a problem of the prior art, and is capable of determining the cause of occurrence of a reconnection process between a USB host and a USB device. An object is to provide a determination device and an image processing device.

  In order to achieve the above object, the present invention employs the following technical means. That is, the USB abnormality cause determination device according to the present invention includes a disconnection history storage unit, a device operation history storage unit, a determination unit, and a notification unit. The disconnection history storage unit stores a disconnection history of the USB device detected by the USB host. The device operation history storage unit stores the operation history of devices arranged around the USB host or USB device. Based on the disconnection history stored in the disconnection history storage unit and the device operation history stored in the device operation history storage unit, the determination unit determines whether the reconnection is caused by the attachment / detachment of the USB device or other causes. Determine if it is caused. The notification unit notifies the determination result of the determination unit.

  In this configuration, since the disconnection history and the device operation history are held, the cause of occurrence when reconnection occurs between the USB host and the USB device can be specified based on these histories. .

  For example, the determination unit can make the following determination as a configuration that makes it much easier to deal with USB abnormality than in the past. First, in the disconnection history stored in the disconnection history storage unit, when the occurrence frequency of disconnection is less than a specified value, it is determined that the cause of reconnection is the attachment / detachment of the USB device. Also, in the disconnect history stored in the disconnect history storage unit, if the frequency of disconnects exceeds the specified value and the disconnect corresponds to the device operation history stored in the device operation history storage unit, It is determined that the cause of the connection is the operation of the device. Furthermore, in the disconnection history stored in the disconnection history storage unit, if the frequency of disconnections exceeds the specified value and does not correspond to the device operation history stored in the device operation history storage unit, the cause of reconnection Determines that there is an abnormality in the connection path between the USB host and the USB device.

  On the other hand, in another aspect, the present invention can also provide an image processing apparatus including the above-described USB abnormality cause determination device.

  According to the present invention, it is possible to determine the cause of occurrence when reconnection processing occurs between a USB host and a USB device.

1 is a schematic configuration diagram showing the overall configuration of a multifunction machine according to an embodiment of the present invention. The figure which shows the hardware constitutions of the multifunctional device in one Embodiment of this invention. 1 is a functional block diagram showing a USB abnormality cause determination device provided in a multifunction machine according to an embodiment of the present invention. FIG. 6 is a diagram for explaining disconnection detection performed by a USB host included in a multifunction peripheral according to an embodiment of the present invention. The flowchart which shows an example of the abnormality cause determination procedure which the USB abnormality cause determination apparatus with which the multifunctional device in one Embodiment of this invention is provided performs

  Hereinafter, an embodiment of the present invention will be described in more detail with reference to the drawings. In the following, the present invention is embodied as a USB abnormality cause determination device provided in a digital multi-function peripheral. The digital multi-function peripheral of this embodiment is configured to be able to execute a plurality of functions including an image reading function, an image processing function, an image forming function (copying function and printer function), a facsimile transmission / reception function, and a network transmission / reception function. Here, a circuit that realizes each function is formed on one or a plurality of substrates for each function, a substrate that realizes an image processing function is a USB host, and a substrate that realizes other functions is a USB device. Each board is connected by a USB interface.

  FIG. 1 is a schematic configuration diagram illustrating an example of the overall configuration of a digital multifunction peripheral according to the present embodiment. As shown in FIG. 1, the multifunction peripheral 100 includes a main body 101 including an image reading unit 120 and an image forming unit 140, and a platen cover 102 attached above the main body 101. A document table 103 is provided on the upper surface of the main body 101, and the document table 103 is opened and closed by a platen cover 102. Further, the platen cover 102 includes a document conveying device 110. An operation panel 171 is provided on the front surface of the multi-function device 100 so that the user can give a copy start or other instruction to the multi-function device 100, and can check the status and settings of the multi-function device 100.

  An image reading unit 120 is provided below the document table 103. The image reading unit 120 reads an image of a document with the scanning optical system 121 and generates digital data (image data) of the image. The document can be placed on the document table 103 or the document transport device 110. The scanning optical system 121 includes a first carriage 122, a second carriage 123, and a condenser lens 124. The first carriage 122 is provided with a linear light source 131 and a mirror 132, and the second carriage 123 is provided with mirrors 133 and 134. The light source 131 illuminates the document. The mirrors 132, 133, and 134 guide reflected light from the document to the condenser lens 124, and the condenser lens 124 forms an optical image on the light receiving surface of the line image sensor 125. In the scanning optical system 121, the first carriage 122 and the second carriage 123 are provided so as to be able to reciprocate in the sub-scanning direction 135. By moving the first carriage 122 and the second carriage 123 in the sub-scanning direction 135, the image of the document placed on the document table 103 can be read by the image sensor 125. When reading an image of a document set on the document conveying device 110, the image reading unit 120 temporarily fixes the first carriage 122 and the second carriage 123 according to the image reading position, and passes the image reading position. Are read by the image sensor 125. The image sensor 125 generates image data of a document corresponding to, for example, each color of R (red), G (green), and B (blue) from the light image incident on the light receiving surface.

  The generated image data can be printed on paper in the image forming unit 140. Further, the data can be transmitted to another device (not shown) through the network 162 by the network adapter 161. Further, facsimile transmission can be performed through the public communication line 164 by the FAX adapter 163.

  The image forming unit 140 receives image data obtained by the image reading unit 120, image data received by the network adapter 161 from another device connected to the network 162, and image data received by the FAX adapter 163 through the public communication line 164. On the paper.

  The image forming unit 140 includes a photosensitive drum 141. The photosensitive drum 141 rotates in one direction at a constant speed. Around the photosensitive drum 141, a charger 142, an exposure unit 143, a developing unit 144, and an intermediate transfer belt 145 are arranged in this order from the upstream side in the rotation direction. The charger 142 uniformly charges the surface of the photosensitive drum 141. The exposure device 143 irradiates the surface of the uniformly charged photoconductor drum 141 with light according to the image data, and forms an electrostatic latent image on the photoconductor drum 141. The developing device 144 attaches toner to the electrostatic latent image and forms a toner image on the photosensitive drum 141. The intermediate transfer belt 145 transfers the toner image on the photosensitive drum 141 onto a sheet. When the image data is a color image, the intermediate transfer belt 145 transfers each color toner image onto the same sheet. The RGB color image is converted into C (cyan), M (magenta), Y (yellow), and K (black) format image data, and the image data of each color is input to the exposure unit 143.

  The image forming unit 140 feeds paper from the manual feed tray 151, the paper feed cassettes 152, 153, and 154 to the transfer unit between the intermediate transfer belt 145 and the transfer roller 146. Various sizes of paper can be placed or stored in the manual feed tray 151 and the paper feed cassettes 152, 153, and 154. The image forming unit 140 selects a sheet specified by the user or a sheet corresponding to the automatically detected document size, and feeds the selected sheet from the manual feed tray 151 or the cassettes 152, 153, and 154 by the feeding roller 155. . The fed paper is transported to the transfer section by transport rollers 156 and registration rollers 157. The sheet on which the toner image is transferred is conveyed to the fixing device 148 by the conveyance belt 147. The fixing device 148 has a fixing roller 158 and a pressure roller 159 with a built-in heater, and fixes the toner image on the sheet by heat and pressing force. The image forming unit 140 discharges the sheet that has passed through the fixing device 148 to the discharge tray 149.

  Note that FIG. 1 schematically shows a board group 181 constituting a USB host and a USB device connected by a USB interface.

  FIG. 2 is a hardware configuration diagram of a control system in the multifunction machine. The multifunction peripheral 100 according to the present embodiment includes a CPU (Central Processing Unit) 201, a RAM (Random Access Memory) 202, a ROM (Read Only Memory) 203, an HDD (Hard Disk Drive) 204, an original transport device 110, and an image reading unit 120. A driver 205 corresponding to each drive unit in the image forming unit 140 is connected via an internal bus 206. The ROM 203, the HDD 204, and the like store programs, and the CPU 201 controls the multifunction peripheral 100 in accordance with instructions from the control program. For example, the CPU 201 uses the RAM 202 as a work area, and controls the operation of each driving unit by exchanging data and commands with the driver 205. The HDD 204 is also used to store image data obtained by the image reading unit 120, image data received from another device through the network adapter 161, and image data received through the FAX adapter 163.

  An operation panel 171 and various sensors 207 are also connected to the internal bus 206. The operation panel 171 receives a user operation and supplies a signal based on the operation to the CPU 201. Further, the operation panel 171 displays an operation screen on a display provided in the operation panel 171 according to a control signal from the CPU 201. The sensor 207 includes various sensors such as an open / close detection sensor for the platen cover 102, a document detection sensor on the document table 103, a temperature sensor for the fixing device 148, and a detection sensor for the conveyed paper or document. The CPU 201 executes, for example, a program stored in the ROM 203 to realize the following means (functional blocks) and controls the operation of each means according to signals from these sensors.

  FIG. 3 is a functional block diagram illustrating the USB abnormality cause determination device provided in the multifunction peripheral according to the present embodiment. As illustrated in FIG. 3, the USB abnormality cause determination device 300 included in the MFP 100 according to the present embodiment includes a disconnection history storage unit 301, a device operation history storage unit 302, a determination unit 303, and a notification unit 304.

  The disconnection history storage unit 301 stores a disconnection history of the USB device 312 detected by the USB host 311. As described above, in this embodiment, a board that realizes an image processing function among the boards included in the board group 181 that implements each function functions as the USB host 311. In addition, a board that realizes another function among the boards included in the board group 181 functions as the USB device 312. In FIG. 4, only two USB devices 312 are illustrated. In the present embodiment, the HDD 204 functions as a storage area of the cutting history storage unit 301.

  Here, the detection of disconnection of the USB device 312 by the USB host 311 will be briefly described. FIG. 4 is a diagram for explaining disconnection detection in the USB 2.0 high-speed mode.

  As described above, in the USB 2.0 standard high speed mode, one of the differential signals D + and D− of the USB interface is at a high level (high potential state) and the other is at a low level (low potential state). Disconnect detection is performed based on the differential signal amplitude (differential voltage value). The connection state and the non-connection state are determined by, for example, determining whether the differential voltage value is equal to or less than the threshold value with 525 mV as a threshold value. That is, when the differential voltage value is less than or equal to the threshold value, it is determined as a connected state, and when the differential voltage value exceeds the threshold value, it is determined as a disconnected state (disconnected).

  As shown in FIG. 4A, when the USB device 312 is connected to the USB host 311, the signal lines that propagate the differential signals D + and D− are on the USB host 311 side and the USB device 312 side. Each is terminated with a 45Ω resistor. The transmission driver 3111 current-drives the differential signals D + and D− so that the differential voltage value becomes 400 mV in this state, and the reception driver 3121 receives the differential signals D + and D−. When the USB device 312 is disconnected in this state, the 45Ω termination resistance on the USB device 312 side disappears, so the differential voltage value is about 800 mV, which is twice 400 mV. In this case, since the differential voltage value exceeds the threshold value of 525 mV, the disconnect detection unit 3112 of the USB host 311 can detect that the USB 312 has been removed.

  In the USB 2.0 standard, data transmission / reception is performed in units of packets, and an EOP (End Of Packet) is provided at the end of each packet. As shown in FIG. 4B, in the EOP, one of the differential signals D + and D− of the USB interface is fixed to a high level, and the other is fixed to a low level. Can be carried out stably.

  When the disconnection of the USB device 312 is detected in the disconnection detection as described above, the USB host 311 stores that fact in the disconnection history storage unit 301 as time-series data. The time series data can be compared with the timing at which the disconnection stored in the disconnection history storage unit 301 occurs and the timing at which the device operation stored in the device operation history unit 302 described later occurs, In addition, any information may be used as long as it is capable of determining the frequency of occurrence of disconnections stored in the disconnection history storage unit 301 (the number of disconnections occurring within a predetermined time, the time interval between disconnections occurring continuously, and the like). Although not particularly limited, in the present embodiment, the USB host 311 acquires time information from the time measuring unit 322 included in the multifunction peripheral 100, and disconnects information specifying the disconnected USB device 312 in association with the time information. Records in the history storage unit 301. The timer unit 322 is configured by a timer that measures time and outputs the time information. Here, the timekeeping unit 322 is configured to be able to time the year, month, day, hour, minute, and second. Note that the time information may be obtained by other methods such as reception of Internet time through the network adapter 161, for example.

  The device operation history storage unit 302 stores an operation history of devices arranged around the USB host 311 or the USB device 312. In the multifunction device 100, all devices in the multifunction device 100 such as the image reading unit 120 and the image forming unit 140 correspond to “devices arranged in the periphery”. In the present embodiment, the operation of each unit in the MFP 100 is configured to be controlled by the operation control unit 321 based on a user instruction through the operation panel 171 or the like. The operation control unit 321 stores the fact in the device operation history storage unit 302 as time-series data when each unit constituting the multifunction peripheral 100 is operated. Note that the devices that store the operation history may be all devices constituting the multi-function device 100, or may be some devices expected to be related to disconnection.

  As described above, the time-series data is a comparison between the timing when the device operation stored in the device operation history unit 302 occurs and the timing when the disconnection stored in the disconnection history storage unit 301 described above occurs. Any information is possible. In the present embodiment, the operation control unit 321 acquires time information in the same manner as the USB host 311. That is, the operation control unit 321 acquires time information from the time measuring unit 322, and records information specifying the operated device in the device operation history storage unit 302 in association with the time information. In the present embodiment, the HDD 204 functions as a storage area of the device operation history storage unit 302.

  Based on the disconnection history stored in the disconnection history storage unit 301 and the device operation history stored in the device operation history storage unit 302, the determination unit 303 determines whether the reconnection process is caused by the attachment / detachment of the USB device 312. Determine whether it is caused by other causes. In the present embodiment, the determination unit 303 determines that the disconnection frequency stored in the disconnection history storage unit 301 is less than a predetermined value in the disconnection history, that is, disconnections are not continuously generated. In this case, it is determined that the cause of the reconnection is removal / attachment of the USB device. In the disconnection history stored in the disconnection history storage unit 301, the determination unit 303 has a disconnection occurrence frequency equal to or higher than the specified value (that is, disconnection occurs continuously), and the disconnection is a device. If it corresponds to the device operation history stored in the operation history storage unit 302, it is determined that the cause of reconnection is the operation of the device. Further, the determination unit 303 corresponds to the device operation history stored in the device operation history storage unit 302 in the disconnection history stored in the disconnection history storage unit 301 with the occurrence frequency of disconnection being equal to or higher than the specified value. If not, it is determined that the cause of the reconnection is an abnormality in the connection path between the USB host 311 and the USB device 312. As the frequency of occurrence of disconnection, data indicating the degree of occurrence of disconnection, such as the number of disconnections that occurred within a predetermined time, the time interval between disconnections that occurred continuously, and the like can be used. In this case, for example, “two disconnects within one minute” or “disconnect time interval of one minute” can be adopted as the specified value. Although not particularly limited, it is assumed here that the former is registered in advance in the determination unit 303 as a specified value.

  In the configuration using the wiring formed on the substrate as the connection path of the USB interface as in the present embodiment, the differential voltage value is 400 mV as determined by the standard due to the variation in the resistance value of the wiring. May be larger. In addition, semiconductor components and resistors constituting the USB interface circuit also have characteristic variations, and some of these components change their characteristics depending on the ambient temperature during use. The differential voltage value may become large due to such component characteristic variations. In addition, in order to realize a differential voltage value of 400 mV defined by the standard with a smaller driving current in response to a recent demand for energy saving, each signal line that propagates each of the differential signals D + and D− In a device adopting the energy saving communication mode in which the termination resistance value is increased, the differential voltage value during communication may be larger due to the above-described wiring resistance value, component characteristic variation, and the like. Under such circumstances, it is assumed that communication is performed in a state in which the differential voltage value during communication is very close to the threshold differential voltage value of 525 mV.

  In this way, when communicating in a situation very close to the threshold for determining disconnection at the time of data transmission / reception, for example, the wiring resistance value increases due to aging of the board, or the differential signal is propagated due to a change in ambient temperature. If the termination resistance of the signal line increases, disconnection is detected and reconnection processing is executed even though the USB device 312 is not actually detached from the USB host 311.

  In the multifunction device 100, devices that emit electromagnetic noise, such as a device that generates a high voltage such as the charger 142 and a device that uses a large current such as the fixing device 148, are in the vicinity of the USB host 311 and the USB device 312. Is arranged. Therefore, if the USB host 311 or the USB device 312 is exposed to the electromagnetic noise for some reason, the disconnection is detected and the USB device 312 is detected even though the USB device 312 is not actually detached from the USB host 311. Connection processing is executed.

  When the frequency at which such reconnection processing is performed becomes high, the period during which data can be transmitted and received via the USB interface is shortened, and as a result, the communication speed decreases and the performance of the multifunction peripheral 100 decreases. . In such a situation, the determination unit 303 performs the above determination, so that the reconnection process is actually the USB device 312 detached from the USB host 311 or is caused by electromagnetic noise. It can be determined whether it is caused by a connection path such as a substrate wiring.

  The notification unit 304 notifies the determination result of the determination unit 303. As the notification method, any method that can be recognized by the user, such as display, printed matter, and e-mail, can be adopted. Here, the notification unit 303 displays the determination result on the display of the operation panel 171.

  Next, an abnormality cause determination procedure performed by the USB abnormality cause determination device 300 included in the multifunction peripheral 100 will be described. FIG. 5 is a diagram illustrating an example of an abnormality cause determination procedure performed by the USB abnormality cause determination device 300 described above. The procedure starts, for example, when the cause determination execution button displayed on the maintenance screen is pressed when a serviceman performs maintenance on the multifunction peripheral 100 as a trigger. In the present embodiment, when a disconnection occurrence is recorded in the disconnection history storage unit 301 in the previous maintenance transition, the notification unit 304 displays that fact on the management screen, and confirms the notification. The service person who has done so can start this procedure.

  When the procedure starts, first, the determination unit 303 reads a disconnection history that is time-series data of disconnection from the disconnection history storage unit 301 (step S501). At this time, the determination unit 303 compares the occurrence frequency of disconnections in the disconnect history with the above-described specified value (step S502). In the determination, when the frequency of occurrence of disconnection is less than the specified value, the determination unit 303 determines that disconnection (that is, reconnection processing) is caused by detachment of the USB device 312 (No in step S502). , S507).

  On the other hand, when the occurrence frequency of disconnection is equal to or higher than the above-described specified value, the determination unit 303 reads out device operation history that is time-series data of device operation from the device operation history storage unit 302 (steps S502 Yes, S503). At this time, the determination unit 303 compares the device operation occurrence timing in the device operation history with the disconnection occurrence timing in the disconnect history (step S504). In the determination, when the generation timing of the device operation corresponds to the generation timing of the disconnection, the determination unit 303 determines that the disconnection is caused by the driving of the device (Yes in steps S504 and S505). Note that the occurrence timing of device operation corresponds to the occurrence timing of disconnection, in addition to the case where the occurrence time is completely the same, as well as the occurrence of disconnection within a predetermined time after the occurrence of device operation. This includes cases where it is recognized that a disconnection has occurred due to operation.

  If the device operation occurrence timing does not correspond to the disconnection occurrence timing in the above determination, the determination unit 303 determines that the disconnection is caused by the connection path of the USB interface (No in step S504). S508).

  The determination unit 303 that has completed the determination as described above notifies the notification unit 304 of the determination result. The notification unit 304 displays the determination result on the display of the operation panel 171 (step S506). The notification includes information for specifying the USB device 312 in which the disconnection has occurred and information for specifying the device.

  In addition, the service person who confirmed the determination result can implement the following countermeasures, for example. In other words, if the determination result is that the USB device 312 has been removed, the serviceman confirms whether there is an abnormality in the connection portion between the boards of the USB interface if he / she has not removed the USB device 312. If there is no abnormality in the connection part, the frequency of disconnection is low at this point, and it is only necessary to follow up. Further, if the USB device 312 is detached from itself, no special action is required. If the determination result is that the device is driven, the service person may perform maintenance or replacement of the notified device, implement electromagnetic noise shielding measures, or the like. Furthermore, when the determination result is a connection path abnormality, the service person may change to the normal communication mode when replacing the notified board or adopting the above-described energy saving communication mode.

  As described above, since the multifunction peripheral 100 holds the disconnection history and the device operation history, when the reconnection occurs between the USB host 311 and the USB device 312 based on these histories. The cause of occurrence can be identified very easily and quickly.

  The above-described embodiments do not limit the technical scope of the present invention, and various modifications and applications other than those already described are possible within the scope of the present invention. For example, in the MFP 100, the service person performs the cause determination at the time of maintenance. However, the cause determination may be performed every time a disconnection occurs. In this case, the notification by the notification unit 304 can employ a configuration in which an e-mail including a determination result is transmitted to a pre-designated mail address.

  In the above description, the time series data is recorded in association with the time information. However, instead of the time information, a clock signal unrelated to the time generated in the multifunction peripheral 100 is used. Alternatively, the frequency of disconnection occurrence and the occurrence timing of disconnection and device operation may be compared.

  Furthermore, in the flowchart shown in FIG. 5, the order of the steps can be changed as appropriate within a range where an equivalent action is achieved. For example, the device operation history can be read simultaneously with the disconnection history.

  In addition, in the above-described embodiment, the present invention has been embodied as a USB abnormality cause determination device for a digital multifunction peripheral. However, the present invention is not limited to a digital multifunction peripheral, and may be applied to an arbitrary image processing apparatus such as a printer or a copier. It is also possible to do. Furthermore, it can be realized as a single USB abnormality cause determination device applicable to any device.

  According to the present invention, it is possible to determine the cause of occurrence when reconnection occurs between a USB host and a USB device, which is useful as a USB abnormality cause determination device and an image processing device.

100 MFP (image processing device)
181 Substrate group 300 USB abnormality cause determination device 301 Cutting history storage unit 302 Device operation history storage unit 303 Determination unit 304 Notification unit 311 USB host 312 USB device

Claims (2)

A USB abnormality cause determination device that determines a cause of occurrence when reconnection occurs between a USB (Universal Serial Bus) host and a USB device,
A disconnection history storage unit for storing a disconnection history of the USB device detected by the USB host;
A device operation history storage unit for storing an operation history of devices arranged around the USB host or USB device;
In the disconnection history stored in the disconnection history storage unit, when the frequency of occurrence of disconnection is less than a specified value, it is determined that the cause of reconnection is removal / attachment of the USB device,
In the disconnection history stored in the disconnection history storage unit, if the frequency of disconnections is equal to or higher than the specified value and the disconnection corresponds to the device operation history stored in the device operation history storage unit, Determine that the cause of the connection is device operation,
In the disconnection history stored in the disconnection history storage unit, when the frequency of disconnection is not less than the specified value and does not correspond to the device operation history stored in the device operation history storage unit, the cause of reconnection Determining that the connection path between the USB host and the USB device is abnormal ,
A notification unit for notifying the determination result of the determination unit;
USB abnormality cause determination device. Image processing apparatus including a USB abnormality cause determination apparatus according to claim 1 Symbol placement.

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