JP2012034077A - Communication apparatus and image forming apparatus with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an abnormal situation in a transmission line from a viewpoint of prevention of a wasted output of a printed matter, identification of a causal position at occurrence of the abnormal situation, determination of presence or absence of the abnormal situation in the transmission line in a development process.SOLUTION: A communication apparatus includes: a timing control unit that controls formation of a synchronizing signal showing that transmission of data is valid or invalid; a transmission unit; a receiving unit; a transmission line through which the data from the transmission unit is transmitted to the receiving unit, by connecting the transmission unit and the receiving unit; a pattern forming unit that forms a test pattern used for confirming whether or not there is an abnormal situation in the transmission of the data from the transmission unit to the receiving unit; and a pattern check unit that is connected to the receiving unit and checks whether or not the test pattern received by the receiving unit matches the test pattern transmitted from the transmission unit. The transmission unit transmits the test pattern in the state in which the synchronizing signal shows that the transmission of data is invalid, and the pattern check unit detects presence or absence of the abnormal situation in the data transmission by checking.

Description

  The present invention relates to a communication device including a transmission unit that transmits data and a reception unit that receives transmitted data, and an image forming apparatus such as a copier, a multifunction peripheral, and a FAX device including the communication device.

  For example, an image reading unit that reads an image of a document and outputs image data may be provided in an image forming apparatus such as a copying machine, a multifunction peripheral, or a FAX machine. Then, when the portion that outputs data such as the image reading unit and the portion that performs processing (for example, printing) based on the data are separated in position, data transmission is performed. In this data transmission, there is a case where data transmission is performed while synchronizing between the transmission side and the reception side from the viewpoint of preventing a timing shift or the like. An invention related to synchronization in such data (video data) transmission is described in Patent Document 1.

  Specifically, Patent Document 1 is a camera video transmission system that transmits video from a transmission side to a reception side and displays the video on a display on the reception side, which is mounted on the transmission side and provided as a parallel signal from the camera. A serializer that converts the vertical sync signal and video data into a serial signal and sends it to the serial signal cable, and a deserializer that is mounted on the receiving side and converts the serial signal given from the serializer through the cable back to a parallel signal and displays it on the display The serializer superimposes the synchronization pattern signal during the video invalid period of the video data and sends it to the cable, and the deserializer determines whether the video is out of synchronization based on the synchronization pattern signal. The camera video transmission system that adjusts the signal to eliminate the loss of synchronization. Temu have been described. With this configuration, it is intended to reduce vehicle harnesses, prevent synchronization loss, and reduce dedicated transmission paths (see Patent Document 1: Claim 1, paragraph [0015], etc.).

JP 2004-208162 A

  Recently, some transmission lines have very high transmission speeds. For example, in an image forming apparatus, an image data transmission line has a high transmission rate. In such a transmission line having a high transmission speed, there is a problem that even a slight contact failure such as a connector causes data corruption. For example, a slight contact failure in the transmission line, such as vibration due to movement or carrying, insertion / removal of a cable, or impact, causes a change in impedance and the like, resulting in data corruption. Data that is garbled cannot be used.

  For example, when image data is garbled in the image forming apparatus, there is a problem that a printed matter of an abnormal image is output, and paper, toner, power, etc. are wasted. If it is late to notice that an abnormal image is formed, a large amount of useless printed matter is output.

  Further, in a manufacturing process (manufacturing line) of an image forming apparatus such as a multifunction machine, for example, an inspection is performed before shipping. An abnormal image output may be confirmed by inspection. Here, there are a number of factors that cause abnormal image output, such as abnormal attachment of transmission lines and image forming members. Therefore, it is necessary to determine the cause of abnormal image output. However, it is difficult to analyze a high-speed transmission line abnormality, which is one of the possible factors, in the manufacturing process. For example, there are difficulties in terms of the necessity of disassembling the assembled image forming apparatus and the necessity of installing a measuring instrument capable of measuring a high-speed transmission line. Therefore, there is a problem that it is difficult to identify a cause site when an abnormality occurs.

  In the development process as well, environmental tests (for example, static electricity tests or impulse tests that intentionally apply static electricity or impulses to image forming devices) can cause high-speed transmission by exceeding the rating of the measuring instrument for the transmission line. Line measurement may not be possible. In such a case, it is difficult to determine whether there is a cause of abnormality in the transmission line.

  Here, the invention described in Patent Document 1 is intended to reduce vehicle harnesses and prevent out-of-synchronization, and the out-of-synchronization may be eliminated. However, it does not address the problem of garbled data even with a slight contact failure such as a connector, and there is no mention of garbled data. Therefore, the above problem cannot be solved.

  In view of the above-mentioned problems of the prior art, the present invention provides a transmission line in view of prevention of useless output of printed matter, identification of a cause part at the time of occurrence of abnormality, determination of presence / absence of abnormality in the transmission line in the development process, and the like. It is an object to detect the abnormality of the earliest.

  In order to achieve the above object, a communication apparatus according to claim 1 includes at least a timing control unit that controls generation of a synchronization signal indicating whether data transmission is valid or invalid, and a state in which the synchronization signal is valid. A transmission unit that transmits data; a reception unit that receives data transmitted by the transmission unit; a transmission line that connects the transmission unit and the reception unit and transmits data from the transmission unit to the reception unit; A pattern generation unit for generating a test pattern for confirming whether or not there is an abnormality in data transmission from the transmission unit to the reception unit, and a test connected to the reception unit and received by the reception unit A pattern check unit that checks whether the pattern matches the test pattern transmitted from the transmission unit, the transmission unit in a state in which the synchronization signal indicates invalid data transmission, Sending a test pattern, the pattern check unit was to detect the presence or absence of abnormality of the data transmitted by the collation.

  According to this configuration, the transmission unit transmits a test pattern in a state where the synchronization signal indicates that data transmission is invalid, and the pattern check unit detects the presence or absence of an abnormality in the transmission through verification. Accordingly, it is possible to detect an abnormality in the data transmission line due to a contact failure of a connector or the like without hindering data transmission. Further, without using a measuring instrument, it is possible to quickly detect that data corruption has occurred in the transmission line between the transmission unit and the reception unit, and the cause of the abnormality can be determined. Further, even if abnormal data is output in the inspection of the communication device manufacturing process (manufacturing line), it can be easily identified that the cause site is the transmission line. Even in the development process, even if the transmission line cannot be measured by an environmental test or the like, it is possible to easily determine whether there is an abnormality in the transmission line.

  According to a second aspect of the present invention, in the first aspect of the invention, when an abnormality in transmission is detected by collation of the pattern check unit, the transmission unit stops data transmission.

  According to this configuration, when an abnormality in transmission is detected by collation of the pattern check unit, the transmission unit stops data transmission. This makes it possible to minimize the reception of abnormal data at the receiving unit. Further, for example, it is possible to eliminate waste associated with receiving abnormal data by the receiving unit, such as printing based on received data.

Further, in the invention according to claim 3, in the invention of claim 1 or 2, the bit string transmitted by the transmitter includes a check bit indicating whether the test pattern is valid or invalid,
The pattern check unit performs collation only when the check bit indicates validity.

  According to this configuration, a check bit indicating whether the test pattern is valid or invalid is included in the bit string of the test pattern, and the pattern check unit performs collation only when the check bit indicates validity. This eliminates the need to always transmit a test pattern in a state where the synchronization signal indicates invalidity. In other words, when the check bit indicates invalidity, the pattern check unit does not detect an abnormality in transmission even if the test pattern is not transmitted. Therefore, to detect abnormalities in transmission, it is only necessary to temporarily enable the check bit and send a test pattern, so that the transmission line can be used less and power consumption is reduced. can do. Further, since the synchronization signal does not have to occupy the entire period indicating that the data transmission is invalid, it can be used for data transmission for another purpose (for example, a synchronization pattern).

  According to a fourth aspect of the present invention, there is provided an image forming apparatus according to any one of the first to third aspects, an image reading unit that reads a document and outputs image data, and an image based on the image data. An image forming unit to be formed, wherein the transmitting unit transmits image data read by the image reading unit, the receiving unit receives the image data, and the image forming unit includes the image forming unit. Printing is performed based on the data, and printing is stopped when an abnormality in transmission is detected by collation of the pattern check unit.

  According to this configuration, the image forming apparatus includes the communication device, and the image forming unit stops printing when an abnormality in transmission is detected by collation of the pattern check unit. Thereby, even if there is an abnormality in the image data, useless printed matter is not continuously output. Further, without using a measuring device, it is possible to quickly detect that image data conversion has occurred in the transmission line between the transmission unit and the reception unit, and to determine the cause of the image data conversion error. Further, even if an abnormal image is output in the inspection of the manufacturing process (manufacturing line), it can be easily specified that the transmission line is the cause. Even in the development process, even when the transmission line cannot be measured by an environmental test or the like, it is possible to easily determine whether or not there is an abnormality in the transmission line.

  As described above, according to the present invention, even if an abnormality occurs in data such as image data due to a slight contact failure of the connector, it is easily and quickly transmitted without using a special measuring instrument. Abnormalities in the line can be detected.

1 is a schematic front sectional view of a multifunction machine according to an embodiment. FIG. 3 is an enlarged cross-sectional view of one image forming unit according to the embodiment. 1 is a block diagram illustrating an example of a hardware configuration of a multifunction machine according to an embodiment. FIG. 2 is a block diagram illustrating an example of a hardware configuration related to image data generation and transmission in the multifunction peripheral according to the embodiment. It is a block diagram which shows an example of the hardware constitutions of the communication apparatus which concerns on embodiment. It is a timing chart which shows an example of the data format in transmission of the communication apparatus which concerns on embodiment. (A) is a timing chart which shows an example of transmission with the communication apparatus which concerns on embodiment of this invention, (b) is the partially expanded view of the area shown to Fig.7 (a). It is a flowchart which shows an example of the flow of communication in the communication apparatus which concerns on embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. In the present embodiment, a multifunction peripheral 100 (corresponding to an image forming apparatus) including the communication apparatus 1 will be described as an example. However, each element such as configuration and arrangement described in this embodiment does not limit the scope of the invention and is merely an illustrative example.

(Schematic configuration of MFP 100)
First, an outline of the multifunction peripheral 100 according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic front sectional view of a multifunction peripheral 100 according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of one image forming unit 51 according to the embodiment of the present invention.

  The multifunction peripheral 100 according to the present embodiment is provided with a document conveying device 101 at the top. Below the document conveying device 101, an image reading unit 2 that reads a document and outputs image data (corresponding to data in claims) transmitted by the communication device 1 is provided. Further, as indicated by a broken line in FIG. 1, an operation panel 3 that functions as a portion for setting printing such as copying is displayed above the front, and displays various types of information for notification. Further, in the MFP 100 main body, a paper feed unit 4a, a conveyance path 4b, an image forming unit 5, an intermediate transfer unit 6a, a fixing unit 6b, and the like are provided.

  When copying a document, the document transport device 101 automatically and continuously scans the documents stacked on the document tray 101A one by one by rotation of a plurality of rollers. It is conveyed toward the contact glass 21A).

  The image reading unit 2 reads a document and generates image data of the document. On the upper surface of the image reading unit 2, a feed reading contact glass 21A and a placement reading contact glass 21B are provided. The image reading unit 2 has an optical system member (FIG. 1) such as an exposure lamp 22 (see FIG. 4), a mirror (not shown), a lens (not shown), and an image sensor 23 (for example, CCD). (Not shown, see FIG. 4). The document conveying device 101 is provided with a fulcrum on the back side of the sheet of FIG. 1 and can be lifted. After the document is placed on the placement reading contact glass 21B, the document conveying device 101 can hold the document.

  The paper feed unit 4a accommodates various sizes of paper (sheets) such as copy paper and label paper, for example, toward the intermediate transfer unit 6a. The paper feed unit 4a feeds one sheet to the transport path 4b by a paper feed roller 41 that is rotated by a drive mechanism (not shown) such as a motor. The conveyance path 4b conveys the sheet in the multifunction peripheral 100 and guides the sheet supplied from the sheet feeding unit 4a to the discharge tray 42 through the intermediate transfer unit 6a and the fixing unit 6b. The conveyance path 4b is provided with a conveyance roller pair 43, a guide 44, and a registration roller pair 45 that waits for the conveyed sheet in front of the intermediate transfer portion 6a and sends it in time.

  Further, as shown in FIG. 1, the multifunction peripheral 100 includes an image forming unit 5 as a part for forming a toner image based on image data of an image to be formed. Specifically, the image forming unit 5 starts from the left side of FIG. 1 with an image forming unit 51Bk (for forming a black toner image), an image forming unit 51Y (for forming a yellow toner image), and an image forming unit 51C ( An image forming unit 51M (for magenta toner image formation), one exposure device 52, and the like.

  Here, the image forming units 51Bk to 51M will be described in detail with reference to FIG. Each of the image forming units 51Bk to 51M has basically the same configuration except that the color of the toner image to be formed is different. Therefore, only one image forming unit 51 is shown in FIG. 2, and in the following description, the symbols for identifying the colors of the respective image forming units 51, Bk, Y, C, and M, are unless otherwise specified. Omitted.

  First, each photosensitive drum 53 has a photosensitive layer made of amorphous silicon or the like, and is rotationally driven at a predetermined process speed by a driving device (not shown) to carry a toner image on the peripheral surface. Each charging device 54 charges the photosensitive drum 53 with a constant potential. The charging device 54 may be one using a corona discharge type or a brush. The exposure device 52 below each image forming unit 51 converts an input color-separated image signal into an optical signal by a laser output unit (not shown), and laser light (converted optical signal). 4) can be output for four colors, and the photosensitive drum 53 after scanning is subjected to scanning exposure to form an electrostatic latent image.

  Each developing device 55 stores a developer (not shown) containing toner (the image forming unit 51Bk has black, the image forming unit 51Y has yellow, the image forming unit 51C has cyan, and the image forming unit 51M. The one contains magenta developer). Each developing device 55 faces the photosensitive drum 53, supplies toner to the photosensitive drum 53 at the time of image formation, and develops the electrostatic latent image as a toner image. Each cleaning device 56 cleans the photosensitive drum 53.

  Returning to FIG. The intermediate transfer unit 6a receives the primary transfer of the toner image from the photosensitive drum 53, and performs the secondary transfer on the paper. The intermediate transfer unit 6a is attached to one of the photosensitive drums 53, and each primary transfer roller 61 (a total of four, 61Bk to 61M), an intermediate transfer belt 62, a driving roller 63, and driven rollers 64 to 66 are provided. It includes a secondary transfer roller 67, a belt cleaning device 68, and the like. Each primary transfer roller 61 transfers the toner image on each photosensitive drum 53 to the intermediate transfer belt 62 while superimposing the toner images without deviation.

  The intermediate transfer belt 62 is stretched around the primary transfer roller 61, the driving roller 63, and the driven rollers 64 to 66, and rotates around the paper surface clockwise in FIG. A predetermined voltage is applied to the secondary transfer roller 67 facing the drive roller 63, and the toner images of the respective colors are transferred to the paper. The residual toner on the intermediate transfer belt 62 after the secondary transfer is removed by the belt cleaning device 68 and collected.

  The fixing unit 6b is disposed on the downstream side in the paper conveyance direction, and fixes the toner image secondarily transferred to the paper by heating and pressing. The fixing unit 6b is mainly composed of a heating roller 69H having a built-in heat generation source and a pressure roller 69P pressed against the heating roller 69H, and forms a nip. The paper on which the toner image is transferred passes through the nip and is heated and pressurized. As a result, the toner image is fixed on the paper. The fixed sheet is discharged to the discharge tray 42 and the image forming process is completed.

(Overview of hardware configuration of MFP 100)
Next, based on FIG. 3, the hardware configuration of the multifunction peripheral 100 according to the embodiment of the present invention will be described. FIG. 3 is a block diagram illustrating an example of a hardware configuration of the multifunction peripheral 100 according to the embodiment of the present invention.

  As shown in FIG. 3, the multifunction peripheral 100 according to the present embodiment includes a main control unit 7 on the control board. The main control unit 7 controls the operation of the entire apparatus and controls each unit of the multifunction peripheral 100. The main control unit 7 includes, for example, a main CPU 70.

  The main control unit 7 is connected to a storage unit 71 including a ROM (Read Only Memory), a RAM (Randam Access Memory), an HDD (Hard Disk Drive), and the like so as to be communicable by a bus or the like. The ROM is a nonvolatile memory that retains stored contents even when the power is turned off. The ROM stores programs executed by the main CPU 70 for control, startup programs, and fixed data for various controls such as various parameters unique to the apparatus. The HDD is used for storing image data, programs, and various management data. Instead of the HDD 8, a storage (for example, SSD) by a semiconductor storage device constituted by a flash ROM or the like may be used.

  The main controller 7 is communicably connected to the image reading unit 2 for reading a document and the document conveying device 101. The main control unit 7 gives an instruction to the image reading unit 2 and the document conveying device 101. In response to this instruction, the image reading unit 2 and the document conveying device 101 rotate various rotating bodies used for reading, such as a roller pair and a lamp 22 for document conveyance, and control of output of image data and the like by the image sensor 23. Actually do.

  The main controller 7 is communicably connected to an engine controller 50 that actually controls paper conveyance and printing. The main control unit 7 gives an instruction to the engine control unit 50. Upon receiving this instruction, the engine control unit 50 rotates various rotating bodies (such as the conveyance roller pair 43 and the photosensitive drum 53) used for paper conveyance and image formation. The unit 5, the intermediate transfer unit 6a, and the fixing unit 6b are controlled.

  The main control unit 7 is connected to a communication unit 73 for performing communication with the outside. The communication unit 73 includes an interface for communicating with the external computer 200 via a network or a cable. For example, the communication unit 73 includes a network connection, a connector for directly connecting the multifunction peripheral 100 and the computer 200, a controller for communication control, and a chip. As a result, the multifunction peripheral 100 can receive and print data including image data from the computer 200 or the like (printer function). In addition, image data obtained by reading by the image reading unit 2 can be transmitted from the multifunction peripheral 100 to the computer 200 (scanner function).

  Further, the communication unit 73 may include an interface for communicating with the counterpart FAX apparatus 300. In other words, the communication unit 73 is also a part for fulfilling a function as a facsimile, and includes a modem, a circuit for converting image data into a format corresponding to a facsimile, and decompressing received data, a chip, and the like ( FAX function).

  The main controller 7 is also communicably connected to the operation panel 3 via a bus or the like. Then, data indicating the setting contents set on the operation panel 3 is sent to the main control unit 7, and the main control unit 7 controls the multifunction peripheral 100 to operate according to the setting of the user.

  In addition, the multifunction peripheral 100 is provided with an image processing unit 8 that performs compression processing on image data and decompression processing of the compressed image data. The image processing unit 8 includes, for example, an ASIC as a circuit dedicated to image processing, a work memory for image processing, and the like (not shown). Then, the image processing unit 8 performs various image processing such as density change and enlargement / reduction on the image data, for example. Since image processing that can be performed by the image processing unit 8 is diverse, the image processing unit 8 is capable of performing image processing related to the known multifunction peripheral 100, and detailed description of executable image processing is omitted.

(Overview of hardware configuration for image data generation and transmission)
Next, an example of image data generation and transmission in the multifunction peripheral 100 according to the embodiment of the present invention will be described with reference to FIG. FIG. 4 is a block diagram illustrating an example of a hardware configuration related to image data generation and transmission in the multifunction peripheral 100 according to the embodiment of the present invention. Note that the flow of image data is indicated by white arrows.

  First, the document conveying device 101 used for document reading in the image reading unit 2 will be described. A document conveyance device 101 disposed above the multifunction peripheral 100 is provided with a document conveyance control unit 102 including circuits and elements such as a controller. The document conveyance control unit 102 is communicably connected to the main control unit 7 of the main body. When reading a document placed on the document tray 101A, such as when a copy start is instructed on the operation panel 3, an instruction is received from the main control unit 7 of the multifunction peripheral 100 main body. The document conveyance control unit 102 controls a document conveyance motor (not shown) that rotates various rotating bodies that convey the document. As a result, the operation of the document feeder 101 is controlled.

  The image reading unit 2 is provided with, for example, a reading control unit 20. The reading control unit 20 includes, for example, a scanner CPU 201 and a board on which various electronic components such as a chip are mounted. The reading control unit 20 is communicably connected to the main control unit 7 and receives an instruction from the main control unit 7 when reading a document, such as when a copy start is instructed on the operation panel 3. Further, the reading control unit 20 is connected to the winding motor M2, the lamp 22, the image sensor 23, and the like. For example, the operation of the winding motor M2 for moving the lamp 22 and various mirrors and a lamp for irradiating light on the document. 22 is turned on and off, and the drive of the image sensor 23 and the like are controlled. Thus, the actual operation control of the image reading unit 2 is performed by the reading control unit 20.

  First, in reading a document and generating image data by the image reading unit 2, the image sensor 23 outputs a current (voltage) corresponding to the intensity of reflected light emitted from the lamp 22 and reflected by the document or the like for each pixel. To do. Note that the image sensor 23 of the present embodiment is a color-compatible line sensor, and outputs R, G, and B signals. Each output current (voltage) of the image sensor 23 is input to the A / D converter 24. An amplifier may be provided before the A / D conversion unit 24.

  For example, the A / D conversion unit 24 converts each analog output current (voltage) of each pixel of the image sensor 23 into digital data and outputs the digital data to the correction unit 25. For example, the A / D converter 24 performs quantization to a total of 24 bits per pixel in RGB (for example, 8 bits each for Red, Green, and Blue, each taking a value of 0 to 255, 256 gradations) .

  The correction unit 25 includes a density adjustment circuit, an arithmetic circuit for correcting the reading characteristics of the image reading unit 2 such as shading correction based on data such as white reference data and black reference data. In general, in the image sensor 23, a reference having the same density in the main scanning direction due to variations (individual characteristic differences) of light receiving elements corresponding to pixels arranged in a line, unevenness in the amount of light emission due to the position of the lamp 22, and the like. Even when a plate or a document is read, a difference occurs in the value of the current (voltage) output from each light receiving element of the image sensor 23 depending on the position of the pixel. Therefore, the correction unit 25 corrects the image data obtained by reading the document.

  Then, the image data is output from the transmission circuit unit 1S of the image reading unit 2 toward the reception circuit unit 1R of the engine control unit 50. For example, the engine control unit 50 is provided with an engine CPU 501 as a controller for controlling each unit.

  The transmission circuit unit 1S and the reception circuit unit 1R constitute the communication device 1 of the present invention. The receiving circuit unit 1R may be provided in the main control unit 7 instead of the engine control unit 50, and image data may be delivered from the main control unit 7 to the engine control unit 50 or the exposure device 52. .

(Hardware configuration of communication device 1)
Next, an example of a hardware configuration of the communication device 1 according to the embodiment of the present invention will be described based on FIGS. 5 and 6. FIG. 5 is a block diagram illustrating an example of a hardware configuration of the communication device 1 according to the embodiment of the present invention. FIG. 6 is a timing chart showing an example of a data format in transmission of the communication device 1 according to the embodiment of the present invention.

  First, the transmission circuit unit 1S will be described. The communication device 1 according to the embodiment of the present invention includes a timing controller 11 (corresponding to a timing control unit), a pattern generation unit 12, a selection unit 13, a transmission unit 14 and the like as a transmission circuit in the transmission circuit unit 1S. . The transmission circuit unit 1 </ b> S configured by these is provided in the image reading unit 2.

  For example, the timing controller 11 receives an instruction from the scanner CPU 201 at the time of copying or scanning, and generates a signal for synchronization in transmission of image data. For example, the timing controller 11 generates a vertical synchronization signal VSYNC (corresponding to a synchronization signal in claims) and a horizontal synchronization signal HSYNC. The vertical synchronization signal VSYNC is a signal that rises at the start point of the image data of one page and falls at the end point (rise and fall may be reversed). In other words, the vertical synchronization signal VSYNC is a signal indicating a break of one page of image data.

  For example, the output of the timing controller 11 is input to the transmission unit 14. The transmission unit 14 starts transmission of image data when the vertical synchronization signal VSYNC rises, then continues transmission of image data, and stops transmission of image data when the vertical synchronization signal VSYNC falls. In other words, in this embodiment, the state in which the vertical synchronization signal VSYNC is High is treated as an effective section in the transmission of image data from the transmission section 14 to the reception section 17 (hereinafter referred to as “image data effective section T1”). ). Then, when the predetermined time has elapsed and the vertical synchronization signal VSYNC rises again, the transmission unit 14 starts transmitting image data of the next page. In other words, the state in which the vertical synchronization signal VSYNC is Low is treated as an invalid section in the transmission of image data from the transmission section 14 to the reception section 17 (hereinafter referred to as “image data invalid section T2”).

  The horizontal synchronization signal HSYNC is a signal indicating a break of one line in one page of image data. The image data is configured by combining a plurality of lines in which a plurality of pixels are arranged in a line. Taking image data corresponding to A4 size at 600 dpi as an example, about 5000 lines are arranged on the short side of the image data (about 21 cm in the case of A4). Therefore, for example, the horizontal synchronization signal HSYNC repeats rising and falling about 5000 times until the vertical synchronization signal VSYNC rises and then falls.

  The pattern generation unit 12 generates a test pattern for confirming whether there is an error such as garbled data in communication between the transmission circuit unit 1S and the reception circuit unit 1R. Then, the test pattern generated by the pattern generation unit 12 is input to the selection unit 13. The output of the timing controller 11 is also input to the pattern generation unit 12. Then, for example, the pattern generation unit 12 generates a test pattern and outputs it to the selection unit 13 until the vertical synchronization signal VSYNC falls and then rises (during the image data invalid interval T2).

  The selection unit 13 is a circuit that receives an input of image data from the correction unit 25 and an input of a test pattern generated by the pattern generation unit 12 and selects and outputs one of them. For example, the selection unit 13 is a multiplexer, and the input destination to be output is switched depending on the state of the vertical synchronization signal VSYNC. For example, the selection unit 13 outputs the image data to the transmission unit 14 when the vertical synchronization signal VSYNC rises and the image data valid section T1. On the other hand, for example, the selection unit 13 outputs a test pattern to the transmission unit 14 when the vertical synchronization signal VSYNC falls and the image data invalid period T2.

  Then, the transmission unit 14 transmits image data and a test pattern in accordance with the vertical synchronization signal VSYNC and the like. A transmission connector CS is provided in the transmission unit 14. One end of the transmission cable 15 (corresponding to a transmission line) is connected to the transmission connector CS.

  Next, the receiving circuit unit 1R will be described. The communication device 1 according to the embodiment of the present invention includes a timing controller 16, a receiving unit 17, a pattern check unit 18 and the like as a receiving circuit. The receiving circuit unit 1 </ b> R configured by these is provided in, for example, the engine control unit 50 (may be the main control unit 7).

  The timing controller 16 receives a synchronization signal (vertical synchronization signal VSYNC or horizontal synchronization signal HSYNC) generated by the transmission-side timing controller 11 and generates a synchronization signal for the engine control unit 50 or the image processing unit 8. Good. The timing controller 16 may confirm the accuracy of the synchronization signal generated by the transmission-side timing controller 11 and whether image data is transmitted in accordance with the synchronization signal.

  Note that the timing controller 16 may generate the vertical synchronization signal VSYNC and the horizontal synchronization signal HSYNC so that the timing controller 11 receives them. In other words, the functions of the timing controller 16 and the timing controller 11 may be reversed.

  The receiving unit 17 receives image data and a test pattern in accordance with a synchronizing signal such as the vertical synchronizing signal VSYNC. A receiving connector CR is provided in the receiving unit 17. One end of the transmission cable 15 is connected to the receiving connector CR. The transmission cable 15 serves as a transmission line, but the transmission unit 14 and the reception unit 17 may be connected to each other by a cable such as a flexible printed board.

  Data transmission between the transmission unit 14 and the reception unit 17 is a serial method. In the present embodiment, the Channel-Link method is adopted as the transmission standard for the transmission unit 14 and the reception unit 17. Note that standards and methods other than Channel-Link may be used. Specifically, image data and test patterns are input to the transmission unit 14 in a parallel manner. Then, the transmission unit 14 converts the parallel data into serial data. The transmission unit 14 transmits serial data to the reception unit 17. On the other hand, the receiving unit 17 converts the received serial data into parallel data.

  Here, based on FIG. 6, an example of a data format when the Channel-Link method is adopted for transmission in the transmission unit 14 and the reception unit 17 will be described. For example, in the Channel-Link system of this embodiment, data transmission is performed using five transmission lines. In other words, the transmission cable 15 includes five transmission lines.

  As shown in FIG. 6, the five transmission lines are divided into one clock signal transmission line (indicated as “CLK” in FIG. 6) and four serial data transmission lines (in FIG. 6, “SAD1 to SAD4”). "). Note that a clock signal transmission line is not required in the case of clock embedded serial transmission.

  In this transmission format, transmission of 7 bits (4 bits for a total of 28 bits) on the serial data transmission lines SAD1 to SAD4 is handled as one cycle. During one cycle, data for one pixel is transmitted. In each serial data transmission line SAD1 to SAD4, B [7] to B [0] are 8-bit blue pixel values, and G [7] to G [0] are 8-bit green pixel values. , R [7] to R [0] are 8-bit red pixel values. Although FIG. 6 shows an example of image data transmission, the test pattern is transmitted through the serial data transmission lines SAD1 to SAD4 in the image data invalid period T2.

  Thus, of the 28 bits transmitted in one cycle, 24 bits are used for transmission of image data and test patterns. The remaining 4 bits are used for purposes other than transmission of pixel values and the like. The bit written as CHK is a check bit that determines whether or not the pattern check unit 18 checks the test pattern.

  For example, if the check bit CHK is High, the pattern check unit 18 checks the test pattern, and if the check bit CHK is Low, the pattern check unit 18 does not check the test pattern. The pattern generation unit 12 may determine and output High and Low of the check bit CHK in accordance with the vertical synchronization signal VSYNC. During transmission of the image data, the correction unit 25 and the transmission circuit unit 1S output the check bit CHK and the image data in which the pattern check unit 18 does not check the test pattern (for example, the check bit CHK). The check bit CHK may be output as image data in which the pattern check unit 18 checks the test pattern (for example, the check bit CHK is set to High). . In any case, the pattern check unit 18 only needs to perform the pattern check only in the image data invalid section T2. Thereby, the pattern generation unit 12 can generate and transmit a test pattern, and the pattern check unit 18 can select the image data invalid section T2 to be checked.

  Of the remaining three bits, the MRE bit is a bit indicating whether or not the image data valid section T1. For example, the High MRE bit is treated as an image data valid section T1, and the Low data is treated as an image data invalid section T2. The VSYNC bit indicates that the vertical synchronization signal VSYNC can be embedded in the data transmission, and the HSYNC bit indicates that the horizontal synchronization signal HSYNC can be embedded in the data transmission.

  Therefore, for example, the vertical synchronization signal VSYNC and the horizontal synchronization signal HSYNC are directly given from the timing controller 11 to each part in the transmission circuit unit 1S, and each part of the reception circuit unit 1R is vertically synchronized with data to be transmitted. The signal VSYNC and the horizontal synchronization signal HSYNC may be confirmed to take vertical synchronization or horizontal synchronization. On the other hand, as shown in FIG. 6, the vertical synchronization signal VSYNC and the horizontal synchronization signal HSYNC are received from the timing controller 11 with each unit (pattern generation unit 12, selection unit 13, transmission unit 14, etc.) of the transmission circuit unit 1 </ b> S. It may be directly given to each part of the circuit unit 1R (the receiving unit 17, the pattern checking unit 18, the receiving-side timing controller 16, etc.). or,

  For example, the data in the image data effective section T1 is output from the receiving unit 17 as image data (for example, output toward the image processing unit 8). On the other hand, the pattern check unit 18 latches the data (test pattern) received by the receiving unit 17 in the image data invalid section T2.

  The pattern check unit 18 checks whether there is an abnormality in the test pattern transmitted in the image data invalid section T2. For example, if the check bit CHK is High and the image data invalid section T2, the pattern check unit 18 compares the test pattern generated by the pattern generation unit 12 with the test pattern received and output by the reception unit 17. Confirm that there is no abnormality in data transmission.

  For verification, the test pattern data generated by the pattern generation unit 12 is transmitted to the engine control unit 50 via the reading control unit 20 and the main control unit 7 and given to the pattern check unit 18 as arbitrary data. Alternatively, the pattern generation unit 12 may generate a predetermined test pattern, and the pattern check unit 18 may collate whether the reception unit 17 receives and outputs the predetermined test pattern.

  If the test pattern received and output by the receiving unit 17 is different from the test pattern generated by the pattern generating unit 12 and there is an abnormality such as garbled data, the pattern check unit 18 has poor contact between the transmission cable 15 and each connector. For example, it is detected that abnormal image data can be transmitted, and the engine CPU 501 is notified that there is an abnormality.

  The receiving unit 17 outputs parallel data. By confirming the position of the garbled data in the parallel data, the pattern checking unit 18 uses any serial transmission line among the serial data transmission lines SAD1 to SAD4. You can also check whether data corruption has occurred. Therefore, in order to perform maintenance accurately, the pattern check unit 18 may notify the engine CPU 501 of the serial transmission line in which data corruption has occurred.

  The engine control unit 50 (engine CPU 501) stops image formation if a toner image (image) is being formed for copying or the like. The engine CPU 501 notifies the main control unit 7 that an abnormality has occurred. Receiving the notification, the main control unit 7 gives an instruction to the scanner CPU 201 (reading control unit 20) that the document should be read. Accordingly, printing is not performed based on abnormal image data, and wasteful consumption of paper and toner can be avoided.

(Data transmission of communication device 1)
Next, an example of transmission of image data and a test pattern in the communication apparatus 1 according to the embodiment of the present invention will be described based on FIG. Fig.7 (a) is a timing chart which shows an example of the transmission in the communication apparatus 1 which concerns on embodiment of this invention, (b) is a partially expanded view of the area shown to Fig.7 (a). .

  First, FIG. 7A will be described. Validity / invalidity of the check shown in FIG. 7A indicates whether or not to perform a pattern check. For example, if High, the pattern generation unit 12 generates a test pattern, and the pattern check unit 18 performs pattern check. The validity of this check is indicated by a check bit CHK.

  The lower part of the check validity / invalidity is a timing chart showing an example of the vertical synchronization signal VSYNC. When the vertical synchronization signal VSYNC is in a high state, the image data is transmitted from the transmission unit 14 to the reception unit 17 (image data valid section T1). On the other hand, when the vertical synchronization signal VSYNC is in a low state, no image data is transmitted (image data invalid period T2), and if the check bit CHK is High, a test pattern is transmitted from the transmission unit 14 to the reception unit 17. The An example of the type of data to be transmitted and the type of section is shown below the timing chart of the vertical synchronization signal VSYNC in FIG.

  7B is an enlarged view of the section A to B in the timing chart of the vertical synchronization signal VSYNC. For example, when the vertical synchronization signal VSYNC is High, one page of image data is transmitted in the image data valid section T1, and the pattern check is not performed. In addition, the vertical synchronization signal VSYNC becomes Low, indicating that the test pattern is transmitted in the image data invalid section T2 and the pattern check is performed.

  Then, the pattern check unit 18 performs a pattern check of the test pattern received and output by the reception unit 17 and outputs High if there is an abnormality such as garbled data. This abnormality is notified to the engine CPU 501 and the like, and image formation and document reading are stopped.

(Flow of communication control)
Next, an example of the flow of communication control in the communication apparatus 1 according to the embodiment of the present invention will be described based on FIG. FIG. 8 is a flowchart showing an example of the flow of communication in the communication apparatus 1 according to the embodiment of the present invention.

  For example, in the start of FIG. 8, the image reading unit 2 starts reading a document for copying or scanning, the image reading unit 2 outputs image data, and the communication device 1 of the present invention starts transmission of the image data. It is time to do. In other words, immediately after the start of a copy or scan job.

  Then, for example, the image data output from the correction unit 25 is input to the communication device 1 (selection unit 13) (step # 1). Further, the timing controller 11 raises the vertical synchronizing signal VSYNC (step # 2). Thereby, the selection unit 13 switches the path, and the image data is input to the transmission unit 14, and the transmission unit 14 starts transmission of the image data to the reception unit 17 while performing parallel-to-serial conversion. (Step # 3).

  Then, the receiving unit 17 starts receiving image data and starts outputting image data while performing serial-to-parallel conversion (step # 4). Then, image data for one page is transmitted, and the vertical synchronization signal VSYNC falls (step # 5). As a result, the image data valid section T1 of the image data ends.

  Next, the pattern generation unit 12 confirms whether or not the test pattern should be checked in the image data invalid section T2 (step # 6). For example, it may be sufficient to check the test pattern from an arbitrary point in time (for example, after turning on the main power supply) a plurality of times (for example, less than 2 to 10 times) in total. On the other hand, the multifunction peripheral 100 includes a document conveying device 101, and can continuously read a plurality of documents.

  Therefore, if the test pattern is checked a predetermined number of times (for example, 10 times) in each image data invalid section T2, the pattern generation unit 12 determines that the test pattern check is unnecessary. It can be arbitrarily determined how many times the test pattern is generated and checked so that the test pattern check is unnecessary. For example, if the number of rising edges of the vertical synchronization signal VSYNC is confirmed from the start of transmission of the first image data, the pattern generation unit 12 can know how many pages of image data have been transmitted continuously.

  When the test pattern check is performed a sufficient number of times and the test pattern check is no longer necessary (No in step # 6), the pattern generation unit 12 does not generate the test pattern and changes the state of the check bit CHK to The pattern check is not executed (step # 7). As a result, the pattern check unit 18 also does not check the test pattern. That is, the bit string of the test pattern includes a check bit indicating whether the test pattern is valid or invalid, and the pattern check unit 18 performs collation only when the check bit indicates valid. Thereafter, the process proceeds to step # 17.

  If the test pattern is to be checked (Yes in step # 6), the selection unit 13 switches the path and the pattern generation unit 12 generates a test pattern (step # 8). The test pattern is input to the transmission unit 14, and the transmission unit 14 starts transmission of the test pattern toward the reception unit 17 while performing parallel-to-serial conversion (step # 9). The receiving unit 17 starts receiving the test pattern, and starts outputting the test pattern while performing serial-to-parallel conversion (step # 10).

  Then, the pattern check unit 18 confirms the check bit CHK in the test pattern (step # 11). At this time, the check bit CHK is in a state instructing execution of the pattern check. Then, the pattern check unit 18 performs test pattern matching (step # 12).

  That is, the communication device 1 of the present invention transmits at least a timing controller 11 (timing control unit) that controls generation of a synchronization signal indicating whether data transmission is valid or invalid, and transmits data in a state where the synchronization signal is valid. A transmission unit 14 that receives the data transmitted by the transmission unit 14, a transmission line that connects the transmission unit 14 and the reception unit 17 and transmits data from the transmission unit 14 to the reception unit 17, A pattern generation unit 12 that generates a test pattern for confirming whether or not there is an abnormality in data transmission from the transmission unit 14 to the reception unit 17, and a test that is connected to the reception unit 17 and received by the reception unit 17 A pattern check unit 18 for checking whether the pattern matches the test pattern transmitted from the transmission unit 14, and the transmission unit 14 invalidates the synchronization signal when transmitting data. In to the state, and sends a test pattern, the pattern check unit 18 detects the presence or absence of abnormality of the data transmitted by the collation.

  If there is an abnormality such as garbled data (Yes in step # 13), the pattern check unit 18 detects the occurrence of abnormality (step # 14) and notifies the engine CPU 501 and the like of the occurrence of abnormality. As a result, the main control unit 7, the engine control unit 50, and the reading control unit 20 stop image formation and document reading (step # 15). Thereby, the transmission part 14 stops transmission of image data. That is, when an abnormality in transmission is detected by the verification of the pattern check unit 18, the transmission unit 14 stops data transmission. The image forming apparatus (multifunction device 100) includes a communication apparatus 1 according to the present invention, an image reading unit 2 that reads a document and outputs image data, and an image forming unit 5 that forms an image based on the image data. The transmission unit 14 transmits the image data read by the image reading unit 2, the reception unit 17 receives the image data, and the image forming unit 5 performs printing based on the image data. When an abnormality in transmission is detected by the verification of the pattern check unit 18, printing is stopped. Then, the occurrence of the data transmission error may be displayed on the liquid crystal display unit of the operation panel 3 to notify the occurrence of the error (Step # 16 → End).

  On the other hand, when the pattern check should not be executed (No in step # 6) or when there is no abnormality such as garbled data (No in step # 13), the reading control unit 20 transmits image data for all originals. It is confirmed whether the process is over (step # 17). If transmission of image data for all the originals has been completed (Yes in step # 17), this control may be terminated (END). On the other hand, if the transmission of the image data for all the originals has not been completed, the process returns to step # 1.

  As described above, according to the present embodiment, the transmission unit 14 transmits the test pattern in a state where the synchronization signal indicates that the data transmission is invalid, and the pattern check unit 18 determines whether there is an abnormality in the transmission through the verification. Is detected. As a result, it is possible to detect data corruption due to contact failure of a connector or the like without hindering data transmission. Further, without using a measuring instrument, it is possible to quickly detect that data corruption has occurred in the transmission line between the transmission unit 14 and the reception unit 17 and find out the cause of the data corruption. Moreover, even if abnormal data is output in the inspection of the manufacturing process (manufacturing line) of the communication device 1, it can be easily identified that the cause part is in the transmission line. Even in the development process, even if the transmission line cannot be measured by an environmental test or the like, it is possible to easily determine whether there is an abnormality in the transmission line.

  Further, when an abnormality in transmission is detected by the verification of the pattern check unit 18, the transmission unit 14 stops data transmission. Thereby, the reception of the abnormal data at the receiving unit 17 can be minimized. Further, for example, it is possible to eliminate waste associated with the reception unit 17 receiving abnormal data such as printing based on the reception data. In addition, a check bit indicating whether the test pattern is valid or invalid is included in the bit string of the test pattern, and the pattern check unit 18 performs collation only when the check bit indicates validity. This eliminates the need to always transmit a test pattern in a state where the synchronization signal indicates invalidity. In other words, when the check bit indicates invalidity, the pattern check unit 18 does not detect an abnormality in transmission even if the test pattern is not transmitted. Therefore, to detect abnormalities in transmission, it is only necessary to temporarily enable the check bit and send a test pattern, so that the transmission line can be used less and power consumption is reduced. can do. Further, since the synchronization signal does not have to occupy the entire period indicating that the data transmission is invalid, it can be used for data transmission for another purpose (for example, a synchronization pattern).

  Further, the image forming apparatus includes the communication device 1, and the image forming unit 5 stops printing when an abnormality in transmission is detected by collation of the pattern check unit 18. Thereby, even if there is an abnormality in the image data, useless printed matter is not continuously output. Further, without using a measuring instrument, it is possible to quickly detect that image data conversion has occurred in the transmission line between the transmission unit 14 and the reception unit 17 and find out the cause of abnormal image data conversion. Further, even if an abnormal image is output in the inspection of the manufacturing process (manufacturing line), it can be easily specified that the transmission line is the cause. Even in the development process, even when the transmission line cannot be measured by an environmental test or the like, it is possible to easily determine whether or not there is an abnormality in the transmission line.

  Next, another embodiment will be described. In the above example, the case where the image data obtained by the image reading unit 2 is transmitted to the engine control unit 50 or the like has been described. For example, the transmission / reception of the test pattern and the pattern check are performed by the multifunction device including the communication device 1. It may be performed when 100 main power supplies are turned on. In addition, transmission / reception of test patterns and pattern check are performed from a power saving mode (for example, a mode in which power supply to the image forming unit 5 and the image reading unit 2 is stopped to save power) to a normal mode (for example, an image forming unit 5 and the mode in which the power supply to the image reading unit 2 is resumed and the MFP 100 is maintained in a state where all the functions of the MFP 100 can be used.

  In the above-described embodiment, the data transmission between the image reading unit 2 and the engine control unit 50 has been described as an example. However, the communication apparatus 1 according to the present invention is also used for other transmission lines in the multifunction peripheral 100. Can do. For example, the communication device 1 according to the present invention is provided between the communication unit 73 and the main control unit 7, and the communication device 1 of the present invention is used to transmit image data received by the communication unit 73 to the main control unit 7. May be.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  The present invention is applicable to a communication device or an image forming apparatus equipped with the communication device.

1 Communication Device 11 Timing Controller (Timing Control Unit)
DESCRIPTION OF SYMBOLS 12 Pattern production | generation part 14 Transmission part 15 Transmission cable (transmission line) 17 Reception part 18 Pattern check part 2 Image reading part 5 Image formation part 100 Multifunction machine (image formation apparatus)
CHK check bit VSYNC Vertical synchronization signal (synchronization signal)

Claims (4)

At least a timing control unit that controls generation of a synchronization signal indicating whether data transmission is valid or invalid; and
A transmission unit for transmitting data in a state in which the synchronization signal indicates validity;
A receiver that receives data transmitted by the transmitter;
A transmission line connecting the transmission unit and the reception unit, and transmitting data from the transmission unit to the reception unit;
A pattern generation unit for generating a test pattern for confirming whether there is an abnormality in data transmission from the transmission unit to the reception unit;
A pattern check unit that is connected to the receiving unit and that checks whether the test pattern received by the receiving unit matches the test pattern transmitted from the transmitting unit;
The transmission device transmits the test pattern in a state in which the synchronization signal indicates data transmission invalidity, and the pattern check unit detects presence or absence of abnormality in data transmission by collation. When an abnormality in transmission is detected by verification of the pattern check unit,
The communication apparatus according to claim 1, wherein the transmission unit stops data transmission. The bit string transmitted by the transmission unit includes a check bit indicating whether the test pattern is valid or invalid,
The communication apparatus according to claim 1, wherein the pattern check unit performs collation only when the check bit indicates validity. The communication device according to any one of claims 1 to 3,
An image reading unit that reads an original and outputs image data;
An image forming unit that forms an image based on the image data,
The transmission unit transmits the image data read by the image reading unit,
The receiving unit receives the image data,
The image forming apparatus performs printing based on the image data, and stops printing when an abnormality in transmission is detected by collation of the pattern check unit.

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