JP2010240937A - Image formation device, image forming system, and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the efficiency of image formation while securing the quality of an image formed in an image forming medium. <P>SOLUTION: An image formation device includes a second memory 76 for storing region information which specifies a packet corresponding to an indispensable image area in printing data, SERDES_IC 65 for transmitting the printing data with the packet as a unit, SERDES_IC 71 for receiving the packet, CPU 74 for determining whether the packet corresponds to the indispensable image area based on region information when not succeeding in receiving the packet even if transmitting the packet a predetermined number of times, a SERDES controller 72 for making the packet of the following turn transmitted when determining that an image area is not the indispensable image area, and a printing data transmitting part 77 for making the image formed with a head 8 based on a plurality of packets received successfully. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus that transmits print data in units of a packet having a predetermined data length in at least a part of a route to supply to a head.

  For example, a printer for industrial use has a high demand for printing speed, and a consumer printer that prints by moving the head in the width direction of the image forming medium (for example, paper) satisfies the demand for the printing speed. I can't. Therefore, a line ink jet printer equipped with a line head capable of ejecting ink over the entire range of one row in the paper width direction and capable of printing in the paper width direction without moving the head is adopted. It has become.

  For example, in a line inkjet printer, variable printing may be performed in which printing contents are changed for each page to be printed. In this variable printing, it is necessary to transmit a large amount of print data at high speed and accurately from a host computer that generates print data to a head controller in the printer.

  For example, a technique for confirming whether print data is correctly transmitted from a host computer to a printer is known (for example, see Patent Document 1).

JP 2003-37992 A

  For example, according to the technique disclosed in Patent Document 1, if the print data transmitted from the host computer to the printer is not sent correctly, an error is displayed, but the printer is not stopped.

  For this reason, even if it is a case where it is not exact print data, printing will be performed and there exists a problem that a useless printed matter will generate | occur | produce.

  On the other hand, if an error occurs and the printer is stopped, there is a problem that the throughput of the printer is reduced.

  The present invention has been made in view of the above problems, and an object thereof is to provide a technique capable of improving the efficiency of image formation while ensuring the quality of an image formed on an image forming medium.

  In order to achieve the above object, according to the present invention, the print data has the importance of data such as image area data essential for printing and image area data not necessarily required for printing. The image forming apparatus according to the first aspect of the present invention has been made paying attention to different points, and at least a part until print data received from an external apparatus is supplied to a head for forming an image. In the image forming apparatus that transmits a packet of a predetermined data length as a unit in the path, a specific information storage unit that stores specific information for specifying a packet corresponding to an image area essential for image formation in the print data, and print data Packet transmitting means for transmitting packets in units, packet receiving means for receiving packets, and packet transmitting means for A packet determination means for determining whether or not the packet is a packet corresponding to an essential image area based on the specific information when the packet reception means does not succeed in receiving the packet even if the number of times is transmitted; When it is determined that the packet is not a packet corresponding to the essential image area, a transmission control unit that causes the packet transmission unit to transmit a packet in the next order, and a plurality of packets that the packet reception unit has successfully received And image forming control means for forming an image by the head.

  According to the image forming apparatus, if the packet is not successfully received even if the packet is transmitted a predetermined number of times, if the packet is not a packet corresponding to the essential image area, the next packet is transmitted. An image is formed based on a plurality of packets successfully received. For this reason, image formation can be continued even if packets outside the essential image area cannot be received. At this time, since the packet of the essential image area has been successfully received, an accurate image can be formed for the essential image area.

  In the image forming apparatus, the specific information storage unit stores a flag management table that stores, for each packet of print data, an essential determination flag indicating whether the packet is a packet corresponding to an essential image area. Also good. According to such an image forming apparatus, it is possible to appropriately determine whether or not the packet is a packet corresponding to an essential image area, using the essential determination flag in the flag management table.

  Further, the image forming apparatus includes a plurality of heads and a plurality of head controllers that transmit data for the heads in the print data to at least one or more heads. A stop control means provided in the head controller, wherein when the packet judging means judges that the packet is a packet corresponding to an essential image area, a stop control means for stopping transmission of print data to the head by all other head controllers; You may make it prepare. According to such an image forming apparatus, when a packet corresponding to an essential image area cannot be transmitted accurately, transmission of print data by another head controller that transmits print data to another head can be stopped. For this reason, it is possible to appropriately stop image formation when an essential image region cannot be appropriately formed. Thereby, it is possible to prevent a useless image from being formed.

  In the image forming apparatus, the packet transmission unit transmits the packet by sequentially transmitting data of a predetermined length as a unit, and the packet reception unit sequentially receives the data of the predetermined length, A ring buffer having the same storage capacity as the data amount, storage means for sequentially storing data of a predetermined length received by the packet receiving means in the storage area in the ring buffer, and the first storage area of the ring buffer is the next storage area The packet was successfully received based on the first area information indicating whether or not the data storage area is stored and the storage status information indicating whether or not the data is stored in the last storage area of the ring buffer. Receiving determination means for determining whether or not the packet determination means transmits the same packet a predetermined number of times by the packet transmission means. , If it is not determined that the packet was received successfully by the receiving determining means may determine whether the packet that the packet corresponding to the required image area. According to the image forming apparatus, the first storage area indicating whether or not the first storage area of the ring buffer is a storage area for storing the next data, and whether or not data is stored in the last storage area of the ring buffer. Based on the storage state information indicating whether or not the amount of data of the received packet is large or small, it is possible to appropriately determine a state where the packet is not correctly transmitted.

  The image forming apparatus may further include notification means for notifying the external apparatus that an error has occurred when it is determined that the packet is an essential image area. According to such an image forming apparatus, when an essential image region packet cannot be received correctly, it is possible to cause an external apparatus to appropriately grasp the occurrence of an error.

  Further, the image forming apparatus includes a plurality of heads and a plurality of head controllers that transmit data for the heads in the print data to at least one or more heads. The notification means provided in the head controller may transmit identification information indicating the head controller in which the error has occurred to an external device. According to the image forming apparatus, it is possible to appropriately grasp the head controller in which an error has occurred in the external apparatus.

  In order to achieve the above object, an image forming system according to a second aspect of the present invention includes a processing device that creates and transmits print data, and a head that forms an image from print data received from the processing device. In an image forming system including an image forming apparatus that transmits a packet having a predetermined data length as a unit in at least a part of a route until supply to the image processing apparatus, the processing device is indispensable for image formation of an image corresponding to print data An essential image area determining unit for determining an image area, a specific information transmitting unit for transmitting specific information for specifying a packet in print data corresponding to the determined essential image area to the image forming apparatus, and the print data as the image forming apparatus A print data transmission means for transmitting the print data to the image forming apparatus, a specific information storage means for storing the specific information, and print data in units of packets. Packet transmitting means for transmitting the packet, packet receiving means for receiving the packet, and packet transmitting means for transmitting the packet a predetermined number of times, but the packet receiving means does not succeed in receiving the packet. The packet determination means for determining whether or not the packet is a packet corresponding to the essential image area; and if the packet is determined not to be a packet corresponding to the essential image area, the packet transmission means Transmission control means for transmitting the packet, and image formation control means for forming an image by the head based on the plurality of packets successfully received by the packet receiving means.

  According to such an image forming system, if the packet is not successfully received even if the packet is transmitted a predetermined number of times, if the packet does not correspond to the essential image area, the next packet is transmitted and received. An image is formed based on a plurality of successful packets. For this reason, image formation can be continued even if packets outside the essential image area cannot be received. At this time, since the packet of the essential image area has been successfully received, an accurate image can be formed for the essential image area.

  In order to achieve the above object, an image forming method according to the third aspect of the present invention provides print data received from an external device in at least a part of a path until the print data is supplied to a head for forming an image. An image forming method by an image forming apparatus that transmits a packet having a predetermined data length as a unit, and specifying information of an image forming apparatus that stores specific information for specifying a packet corresponding to an image area essential for image formation in print data A storage step for storing in the storage unit, a packet transmission unit for the packet transmission unit of the image forming apparatus to transmit print data in units of packets, and a packet reception step for the packet reception unit of the image forming apparatus to receive the packet; Even if the packet determination unit of the image forming apparatus transmits the packet a predetermined number of times, the packet transmission unit A packet determination step for determining whether or not the packet is a packet corresponding to an essential image area based on the specific information when the communication means has not successfully received the packet; and a transmission control means for the image forming apparatus However, when it is determined that the packet is not a packet corresponding to the essential image area, a transmission control step for causing the packet transmission unit to transmit a packet in the next order, and an image formation control unit of the image forming apparatus, An image forming control step of forming an image by the head based on the plurality of packets successfully received by the packet receiving means.

  According to the image forming method, if the packet is not successfully received even if the packet is transmitted a predetermined number of times, the next packet is transmitted if the packet does not correspond to the essential image area. An image is formed based on a plurality of successful packets. For this reason, image formation can be continued even if packets outside the essential image area cannot be received. At this time, since the packet of the essential image area has been successfully received, an accurate image can be formed for the essential image area.

1 is a functional configuration diagram of an image forming system according to an embodiment of the present invention. FIG. 2 is a partial configuration diagram around a head of a printer according to an embodiment of the present invention. It is a figure explaining the printing data and printing essential area | region which concern on one Embodiment of this invention. It is a block diagram of the main controller which concerns on one Embodiment of this invention. It is a block diagram of the distribution controller which concerns on one Embodiment of this invention. It is a block diagram of the head controller which concerns on one Embodiment of this invention. It is a block diagram of the SERDES controller which concerns on one Embodiment of this invention. It is a block diagram of the area | region information management table which concerns on one Embodiment of this invention. It is a flowchart of the process of the main controller in the printing process which concerns on one Embodiment of this invention. 6 is a flowchart of processing performed by a CPU of a head controller in printing processing according to an embodiment of the present invention. It is a flowchart of the process of the SERDES controller in the printing process which concerns on one Embodiment of this invention.

  Embodiments of the present invention will be described with reference to the drawings. The embodiments described below do not limit the invention according to the claims, and all the elements and combinations described in the embodiments are essential for the solution of the invention. Is not limited.

  First, an image forming system according to an embodiment of the present invention will be described.

  FIG. 1 is a functional configuration diagram of an image forming system according to an embodiment of the present invention.

  The image forming system 1 includes a PC (Personal Computer) 2 as an example of an external device and a processing device, and a printer 3 as an example of an image forming device.

  The printer 3 includes a main controller 4, a transfer controller 5, a plurality of distribution controllers 6, a plurality of head controllers 7, and a plurality of heads 8.

  The PC 2 is connected to the main controller 4 via a cable (for example, a USB (Universal Serial Bus) cable). The PC 2 is connected to the transfer controller 5 by a cable (for example, an optical cable).

  The main controller 4 and the plurality of head controllers 7 are connected by a ring network. In the present embodiment, this network performs communication using a CAN (Control Area Network) communication method, for example. The transfer controller 5 and the plurality of distribution controllers 6 are connected by, for example, a ring network. In the present embodiment, this network performs communication using, for example, an optical communication method. The distribution controller 6 is connected to one or more head controllers 7. The head controller 7 is connected to one or more (for example, two) heads 8.

  FIG. 2 is a partial configuration diagram around the head of the printer according to the embodiment of the present invention.

  The printer 3 includes a belt 10 that transports paper (image forming medium) such as paper, an OHP sheet, and cloth supplied from a paper feed tray (not shown). The belt 10 is driven by a motor (not shown). When printing on paper (also called printing or image formation), the belt 10 transports the paper in the transport direction, that is, from the upstream side (left side in FIG. 2) to the downstream side (right side in FIG. 2) at a substantially constant speed. To do.

  The printer 3 can print on a plurality of sizes of paper. In the present embodiment, the printer 3 can print paper of various sizes up to a width W (maximum printable width) as shown in FIG. In the present embodiment, the paper is transported so that the center of the paper is positioned substantially at the center of the belt 10.

  The printer 3 has a plurality of head rows 9 (9A, 9B) arranged in the paper transport direction X. The head row 9 has a plurality of heads 8.

  The head 8 is provided with a plurality of nozzles (not shown) that eject ink toward the side on which the paper is conveyed (the lower side in FIG. 2). In the present embodiment, the head 8 is formed with, for example, a nozzle row in which a plurality of (for example, 180) nozzles are arranged in the paper width direction Y perpendicular to the paper transport direction X. A plurality of rows (for example, 8 rows) are arranged in X. The printer 3 performs printing with, for example, four colors of ink. Two nozzle rows are assigned to each of yellow, magenta, cyan, and black, and the same color nozzle row is defined in the paper width direction Y. The positions of the nozzles are arranged so as to be shifted by a predetermined amount (for example, half the nozzle pitch in the nozzle row). The head 8 is provided with a piezoelectric vibrator (not shown) that expands and contracts according to the supplied drive signal so as to correspond to each nozzle. The head 8 can control the ejection of ink from the nozzles by controlling the expansion and contraction of the piezoelectric vibrator by controlling the supply of the drive signal to the piezoelectric vibrator based on the print data.

  As shown in FIG. 2, each head row 9 (9 </ b> A, 9 </ b> B) is configured such that a plurality of heads 8 are arranged in a staggered manner (alternately) in the paper width direction Y. The plurality of heads 8 arranged on the upstream side of the head row 9 are arranged along the paper width direction Y with a predetermined interval. Each of the plurality of heads 8 arranged on the downstream side is arranged so as to supplement printing of a portion (for example, between the heads 8) that cannot be printed by the upstream head 8 in the maximum printable width W. As described above, by arranging the plurality of heads 8, ink can be ejected at a predetermined resolution (for example, 360 dpi) over the entire maximum printable width W in the paper width direction.

  In the present embodiment, the paper of the nozzles of each head 8 of the head row 9A at the front stage and the corresponding head 8 (head 8 for printing substantially the same range in the paper width direction) of the head row 9B at the rear stage. The arrangement position in the width direction is different. That is, the arrangement position of the nozzles in the paper width direction of the head 8 in the head row 9A in the preceding stage is shifted from the arrangement position in the paper width direction of the nozzles of the corresponding head in the head row 9B by half the nozzle pitch. . In this way, the arrangement positions of the nozzles of the corresponding heads 8 of the head row 9A and the head row 9B in the paper width direction are shifted by a half of the nozzle pitch, so the head row 9A at the front stage and the head row 9B at the rear stage. When the image is formed by the above, an image having a resolution (for example, 720 dpi) double that of the image that can be formed by the head row 9A in the previous stage can be formed.

  Returning to the description of FIG. 1, the PC 2 includes, for example, a RAM, a CPU, an input / output device, and the like. Here, the CPU is an example of an essential image area determination unit, a specific information transmission unit, and a print data transmission unit. In the PC 2, when the CPU executes a predetermined program, print data used for image formation (printing) of the printer 3 is generated based on the image data of an image to be formed, and the print data is stored in the printer 3. Transmit to the transfer controller 5.

  Further, in the PC 2, the CPU executes a predetermined program to accept designation of an image area essential for printing in an image from the user, and essential area information (specific information) indicating the essential image area (print essential area). ) To the main controller 4 of the printer 3. Note that the CPU may specify the required image area in the image according to a predetermined standard.

  In the PC 2, the CPU receives error information from the main controller 4 of the printer 3 and displays the error information on the input / output device.

  FIG. 3 is a diagram for explaining print data and a print essential area according to an embodiment of the present invention.

  The print data includes gradation value data (gradation data) corresponding to all dots in the paper conveyance direction for all nozzles (13680: 720 dpi × 29 inches) in the paper width direction in the printer 3. . In the present embodiment, in the printer 3, 512-byte (byte) gradation data (packet) for each nozzle may be transmitted as a unit. In the present embodiment, there are 18 packets in the paper transport direction.

  In the PC 2, an image of the print data shown in FIG. 3 is displayed on the input / output device, and an indispensable image area is designated by the user in the image. According to the designated essential image area, based on the position of the essential image area in the image, data (packet) corresponding to the print mandatory area in the print data can be specified as shown in FIG.

  FIG. 4 is a configuration diagram of a main controller according to an embodiment of the present invention.

  The main controller 4 includes a USB interface 41, an SDRAM (Synchronous Dynamic Random Access Memory) 42, a CPU 43 as an example of a notification unit, and a CAN communication controller 44.

  The USB interface 41 mediates USB communication with the PC 2. The CAN communication controller 44 mediates CAN communication with the head controller 7. The SDRAM 42 stores various information.

  The CPU 43 performs overall control of the units 41, 42, and 44 and performs various processes. The CPU 43 receives essential area information transmitted from the PC 2 via the USB interface 41, and based on the essential area information, whether or not each packet of print data for one page is data of an essential image area. Is generated and stored in the SDRAM 42. Further, the CPU 43 acquires area information indicating whether or not the data to be transmitted is an essential image area data for the packet transmitted to the head 8 of each head controller 7 from the SDRAM 42, and sends each head controller 7 via the CAN communication controller 44. To send. Further, the CPU 43 receives a print stop request from the head controller 7 via the CAN communication controller 44 and transmits the print stop request to the PC 2 via the USB interface 41. If the print stop request is due to a data transmission error, the CPU 43 transmits error information including identification information of the head controller 7 in which the data transmission error has occurred to the PC 2. The CPU 43 receives a print stop request from the head controller 7 via the CAN communication controller 44 and transmits a print stop command to each head controller 7 via the CAN communication controller 44.

  Returning to the description of FIG. 1, the transfer controller 5 receives print data from the PC 2 and transmits it to each distribution controller 6.

  FIG. 5 is a configuration diagram of a distribution controller according to an embodiment of the present invention.

  The distribution controller 6 includes a communication interface 61, a CPU 62, a RAM 63, a SERDES (serializer / deserializer) controller 64, and a SERDES_IC (Integrated Circuit) 65 as an example of a plurality of packet transmission means.

  The communication interface 61 receives print data from the transfer controller 5, passes it to the CPU 62, and transmits the received print data to the next distribution controller 6 (or transfer controller 5). The CPU 62 stores, in the RAM 63, data of the portion for the head 8 that is managed by the distribution controller 6 of the received print data. The SERDES controller 64 takes out packets of a predetermined data length of the print data from the RAM 63 in a predetermined order and passes them to the SERDES_IC 65 connected to the head 8 that uses the data of each packet. The SERDES_IC 65 cuts the received packet into data having a predetermined data length (for example, 16 bits) and sequentially transmits the data to the head controller 7. Further, when receiving a retransmission request from the head controller 7, the SERDES_IC 65 retransmits the same packet.

  FIG. 6 is a configuration diagram of a head controller according to an embodiment of the present invention.

  The head controller 7 includes a SERDES_IC 71 as an example of a packet receiving unit, a SERDES controller 72 as an example of a transmission control unit, a CAN communication controller 73, a CPU 74 as an example of a packet determination unit and a stop control unit, and a first memory. 75, a second memory 76 as an example of a specific information storage unit, and a print data transmission unit 77 as an example of an image formation control unit.

  The SERDES_IC 71 sequentially receives the packets in units of data for each predetermined data length and passes them to the SERDES controller 72. The SERDES_IC 71 transmits a packet retransmission request to the SERDES_IC 65.

  The SERDES controller 72 is configured by, for example, an FPGA (Field Programmable Gate Array), and manages packet reception processing and the like.

  FIG. 7 is a configuration diagram of a SERDES controller according to an embodiment of the present invention.

  The SERDES controller 72 includes a data reception unit 72a, a RAM management unit 72b as an example of a storage unit, and a data transmission unit 72c.

  In the data receiving unit 72a, a LOCK indicating a communication state (synchronization presence / absence) between the data signal including the data transmitted from the SERDES_IC 65 of the distribution controller 6, the control signal (STB, PCK) from the SERDES_IC 65, and the SERDES_IC 65. A signal, a data full signal (storage state information) indicating whether or not the RAM on the reception side of the RAM management unit 72b is in a data full state, and the address of the write destination of the RAM on the reception side of the RAM management unit 72b are 0 addresses. And an address 0 signal (head area information) indicating whether or not the control signal and a control signal including a control command from the CPU 74 are input.

  When reception of a packet fails, the data receiving unit 72a initializes the write destination address of the RAM on the receiving side to address 0, and sets an address initialization signal to a predetermined state in order to put the receiving RAM in an empty state. (For example, high) and output to the RAM management unit 72b.

  The data receiving unit 72a outputs a data signal for transmitting the received data to the RAM managing unit 72b.

  The data receiving unit 72a outputs a RAM lock signal for locking the RAM used as the receiving-side RAM among the two RAMs of the RAM managing unit 72b. For example, when receiving a new packet, the data receiving unit 72a switches the RAM to be locked by a RAM lock signal.

  Based on the data full signal and the address 0 signal, the data receiving unit 72a determines whether the packet has been successfully received. If the packet has been successfully received, the data receiving unit 72a prepares to receive the next packet. On the other hand, until the predetermined number of failures, the ERR signal is transmitted to the SERDES_IC 65 as a state of requesting data retransmission to prepare for re-reception, and when the predetermined number of times fails, a data reception error interrupt signal is sent to the CPU 74. Output. Here, when the data full signal indicates that the data is not full, it can be understood that the data of the packet is missing, the data full signal indicates that the data is full, and the address 0 signal is When the next write destination indicates that the address is 0, it is possible to know that the reception of the packet of the predetermined length has been successful, the data full signal indicates that the data is full, and the address If the 0 signal indicates that the next write destination is not address 0, it can be understood that the data is excessive. In addition, when receiving a command to start reception of the next packet from the CPU 74, the data reception unit 72a prepares for reception of the next packet.

  The RAM management unit 72b has, for example, a plurality of RAMs (for example, two) as internal buffer memories, and when a part is a reception RAM, the remaining can be used as a transmission-side RAM. It has become. Each RAM has the same storage capacity as the packet data (for example, 512 bytes), and the data is stored in order from the top address. When data is stored up to the last address, the data is again stored at the top address. It is a ring buffer that can be stored.

  When the RAM management unit 72b receives data from the data reception unit 72a, the RAM management unit 72b stores the data in order from the top of the reception side RAM. If the address initialization signal indicates that the RAM is empty, the RAM management unit 72b clears the RAM and sets the write destination as the top address.

  In addition, when the RAM storage area becomes full, the RAM management unit 72b outputs a data full signal in a predetermined state (for example, high). Further, when the RAM write destination address is 0, the RAM management unit 72b outputs the address 0 signal in a predetermined state (for example, high). The RAM management unit 72b extracts data from the transmission side RAM and outputs the data to the data transmission unit 72c.

  The data transmission unit 72c includes a data signal including data from the RAM management unit 72b, a data full signal indicating whether or not the RAM on the transmission side of the RAM management unit 72b is in a data full state, and the RAM management unit 72b. An address 0 signal indicating whether or not the write destination address of the RAM on the transmission side is 0 is input.

  The data transmission unit 72c receives data from the RAM management unit 72b, outputs a data signal to be transmitted to the first memory 75, and outputs a write destination address to which the data of the packet is written. Further, when the data transmission unit 72c receives an instruction to start reception of the next packet from the CPU 74, the data transmission unit 72c advances the address of the storage area to which the next packet is written in the first memory 75 by one packet. . In addition, the data transmission unit 72c outputs a RAM lock signal for locking a RAM used as a transmission side RAM among the two RAMs of the RAM management unit 72b. For example, when transmitting a packet from another RAM in which the packet is written, the data transmission unit 72c switches the RAM to be locked by a RAM lock signal.

  Returning to the description of FIG. 6, the CAN communication controller 73 mediates communication by CAN with the connected parts (main controller 4, head controller 7). The CAN communication controller 73 receives and passes it to the CPU 74 when the area information transmitted from the upper part is addressed to its own head controller 7. Send region information to In addition, when the CAN communication controller 73 receives a print stop command from the upper part, the CAN communication controller 73 transmits the print stop command to the CPU 74 and transmits the print stop command to the lower part.

  The first memory 75 is, for example, a RAM, and stores print data. The second memory 76 is, for example, a RAM, and stores an area information management table 76a as an example of a flag management table for managing area information.

  FIG. 8 is a configuration diagram of an area information management table according to an embodiment of the present invention.

  As shown in FIG. 8, the area information management table 76a corresponds to an essential image area for each packet in the entire transport direction in all nozzles (for example, 720) of each head 8 managed by its own head controller 7. An essential determination flag (region information) indicating whether the packet is a packet is stored. In the present embodiment, for example, when the corresponding packet is an essential image area, the essential determination flag is “1”, and when the corresponding packet is not an essential image area, the essential determination flag is “0”. ing.

  Returning to the description of FIG. 6, the CPU 74 executes various processes. In this embodiment, when the CPU 74 receives area information from the CAN communication controller 73, the CPU 74 stores the area information in the area information management table 76 a of the second memory 76.

  When the CPU 74 receives a data reception error interrupt signal from the SERDES controller 72, the CPU 74 refers to the essential determination flag corresponding to the packet in the area information management table 76a of the second memory 76, and It is determined whether or not the packet is a packet in the essential image area. If the packet is not in the essential image area, the SERDES controller 72 issues a command to start receiving the next packet, while the essential image area The print data transmission unit 77 is instructed to stop printing, and the CAN communication controller 73 transmits a print stop request to the main controller 4. Further, the CPU 74 causes the CAN communication controller 73 to transmit error information indicating that the print stop request is a data transmission error to the main controller 4. Further, when the CPU 74 receives a print stop command from the CAN communication controller 73, the CPU 74 instructs the print data transmission unit 77 to stop printing.

  The print data transmission unit 77 transmits the print data stored in the first memory 75 to the connected head 8.

  Next, operations in print processing by the image forming system will be described.

  FIG. 9 is a flowchart of the process of the main controller in the printing process according to the embodiment of the present invention.

  This process is started based on reception of essential area information from the PC 2 via the USB interface 41. Based on the received essential area information, the CPU 43 of the main controller 4 generates area information indicating whether each packet of print data for one page is data of an essential image area, and stores it in the SDRAM 42 ( Step S1).

  Next, the CPU 43 divides the area information stored in the SDRAM 42 into area information for each packet to be transmitted to each head controller 7 (step S2), and sends the divided area information to the corresponding head controller 7 as a CAN communication controller. (Step S3). Next, the CPU 43 issues a print start command to each head controller 7 via the CAN communication controller 44 (step S4).

  Thereafter, the CPU 43 determines whether or not there is a print stop request from the head controller 7 via the CAN communication controller 44 (step S5). If there is no print stop request (step S5: NO), the printing is continued. (Step S6), the process proceeds to Step S5. On the other hand, if there is a print stop request (step S5: YES), the CPU 43 issues a print stop command to each head controller 7 via the CAN communication controller 44 (step S7). Thereby, each head controller 7 stops the process regarding printing.

  Next, the CPU 43 issues a print stop request to the PC 2 via the USB interface 41 (step S8), and notifies the error information including the identification information of the head controller 7 in which the data transmission error has occurred as a stop due to the data transmission error. (Step S9), the process ends. As a result, in the PC 2, the input / output device displays that a data transmission error has occurred and information indicating the head controller 7.

  FIG. 10 is a flowchart of processing by the CPU of the head controller in the printing processing according to an embodiment of the present invention.

  This process is executed based on the CPU 74 receiving a command from the main controller 4 via the CAN communication controller 73.

  First, the CPU 74 determines what the content of the received command is (step S11).

  If the content of the command is a print stop command, the CPU 74 stops printing by causing the print data transmission unit 77 to stop transmitting print data (step S12), and ends the process.

  If the content of the command is a region information setting command, the CPU 74 stores the region information included in the region information setting command in the region information management table 76a of the second memory 76 (step S13). The process ends.

  When the content of the command is a print start command, the CPU 74 causes the SERDES controller 72 to start processing for receiving print data from the distribution controller 6, and causes the print data transmission unit 77 to store the first memory 75. When the stored print data comes at a predetermined time, printing is started by transmitting the print data to the head 8 (step S14).

  Next, the CPU 74 determines whether or not there is a reception error, that is, whether or not a data reception error interrupt signal has been received from the SERDES controller 72 (step S15).

  As a result, when the data reception error interrupt signal has not been received (step S15: NO), it means that the data has been successfully received, so the CPU 74 determines whether or not printing has ended. Determination is made (step S16).

  As a result, when the printing is finished (step S16: YES), the CPU 74 finishes this process. On the other hand, when the printing is not finished (step S16: NO), the process from step 15 is performed. Run again.

  On the other hand, if an interrupt signal indicating a data reception error is received in step S15 (step S15: YES), it means that the reception of data (packet) has failed a predetermined number of times. By determining whether or not the packet is an essential image area packet, it is determined whether or not printing is impossible unless the packet is received (step S17).

  As a result, if printing is not impossible (step S17: NO), that is, if the packet that could not be received correctly is not a packet in the essential image area, the CPU 74 issues a print restart command to the SERDES controller 72 ( The process proceeds to step S18) and step S16. As a result, the SERDES controller 72 causes the SERDES_IC 71 to execute reception processing for the next packet.

  On the other hand, if printing is not possible (step S17: YES), that is, if the packet that could not be received correctly is a packet in the essential image area, if printing is continued as it is, printing will be wasted. The CPU 74 causes the print data transmission unit 77 to stop transferring the print data to the head 8 to stop printing (step S19). Next, the CPU 74 issues a print stop request to the main controller 4 via the CAN communication controller 73 (step S20), and ends the process. Thereby, in the main controller 4, the process of step S7-step S9 shown in FIG. 9 will be performed.

  According to the above processing, even if packet reception fails a predetermined number of times, if the packet that could not be received correctly is not a packet in the essential image area, printing can be continued, so that throughput in printing is improved. be able to.

  FIG. 11 is a flowchart of the process of the SERDES controller in the printing process according to an embodiment of the present invention.

  This process is started when the CPU 74 receives a data reception request instruction.

  First, when there is a data reception request from the CPU 74, the SERDES controller 72 transmits a packet transmission request in the next order to the distribution controller 6 by the SERDES_IC 71 (step S31).

  Next, the SERDES controller 72 determines whether or not the reception of data corresponding to the transmission request is completed (step S32), and when the reception is not completed, waits until the reception is completed.

  On the other hand, when the data reception is completed (step S32: YES), it is determined whether or not the data full signal is high (HIGH), that is, whether or not the internal reception side RAM is in the data full state. When the determination is made (step S33) and the data full signal is high (step S33: YES), the SERDES controller 72 further determines whether or not the address 0 signal is high (HIGH) (step S34). ).

  As a result, when the data full signal is high and the address 0 signal is high (step S34: YES), it means that the packet having a predetermined data length has been successfully received, so the SERDES controller 72 clears the error count stored therein (step S35), and determines whether or not the reception of all packets has been completed (step S36).

  If the reception of all packets is completed (step S36: YES), the process is terminated. If the reception of all packets is not completed (step S36: NO), the process proceeds to step S31.

  On the other hand, if the data full signal is not high in step S33 (step S33: NO), it means that the data of the packet is missing, so the SERDES controller 72 counts up the error count (+1) (Step S37), it is determined whether or not the error count is a predetermined number or more (for example, 5 or more) (Step S38).

  As a result, if the error count is equal to or greater than the predetermined number (step S38: YES), it means that the reception has not been successful even if the same packet is transmitted a predetermined number of times or more. An error interrupt is issued to the CPU 74, the error count is cleared, and the process is temporarily stopped (step S39). Thereafter, when it is determined in step S17 in FIG. 10 that printing is not impossible and a print resumption instruction is transmitted to the SERDES controller 72, the processing from step S31 is resumed.

  On the other hand, when the error count is not equal to or greater than the predetermined number (step S38: NO), the SERDES controller 72 causes the distribution controller 6 to transmit a retransmission request for the same packet to the distribution controller 6 by the SERDES_IC 71 (step S40), and proceeds to step S32. .

  In step S34, if the address 0 signal is not high (step S34: NO), it means that there is too much data in the packet. Therefore, the SERDES controller 72 increments the error count (+1). (Step S41), it is determined whether or not the error count is a predetermined number or more (Step S42).

  As a result, if the error count is a predetermined number or more (for example, 5 or more) (step S42: YES), it means that reception could not be successful even if the same packet was transmitted a predetermined number of times or more. The SERDES controller 72 issues a reception error interrupt to the CPU 74, clears the error count, and temporarily stops processing (step S43). Thereafter, when it is determined in step S17 in FIG. 10 that printing is not impossible and a print resumption instruction is transmitted to the SERDES controller 72, the processing from step S31 is resumed.

  On the other hand, if the error count is not greater than or equal to the predetermined number (step S42: NO), the SERDES controller 72 causes the distribution controller 6 to transmit a retransmission request for the same packet to the distribution controller 6 using the SERDES_IC 71 (step S40), and proceeds to step S32. .

  Although the present invention has been described based on the embodiments, the present invention is not limited to the above-described embodiments, and can be applied to various other modes.

  For example, in the above embodiment, the main controller 4 and the transfer controller 5 are provided, and data is transmitted from the PC 2 to each of the different paths. For example, both the main controller 4 and the transfer controller 5 are provided. It is also possible to provide a functional unit having the above functions and transmit data from the PC 2 through one path.

  In the above embodiment, the head row is constituted by a plurality of heads. However, the present invention is not limited to this, and the head row may be constituted by a single head. Moreover, although the example which applied this invention to the line inkjet printer was shown in the said embodiment, this invention is not restricted to this, You may make it apply to the inkjet printer to which a head moves.

1 image forming system, 2 PC, 3 printer, 4 main controller, 5 transfer controller, 6 distribution controller, 7 head controller, 8 head, input / output unit, 9 head row, 10 belt, 41 USB interface, 42 SDRAM, 43 CPU 44 CAN communication controller, 61 communication I / F unit, 62 CPU, 63 RAM, 64 SERDES controller, 65, 71 SERDES_IC, 72 SERDES controller, 72a data reception unit, 72b RAM management unit, 72c data transmission unit, 73 CAN communication Controller, 74 CPU, 75 1st memory, 76 2nd memory, 77 Print data transmission part.

Claims (8)

In an image forming apparatus that transmits print data received from an external device as a unit of a packet having a predetermined data length in at least a part of a route until the print data is supplied to a head for forming an image.
Specific information storage means for storing specific information for specifying a packet corresponding to an image area essential for image formation in the print data;
Packet transmission means for transmitting the print data in units of the packet;
A packet receiving means for receiving the packet;
Even if the packet transmission means transmits the packet a predetermined number of times, if the packet reception means does not succeed in receiving the packet, the packet corresponds to the essential image area based on the specific information. A packet determination means for determining whether the packet is a packet;
When it is determined that the packet is not a packet corresponding to an indispensable image area, a transmission control unit that causes the packet transmission unit to transmit a packet in the next order;
An image forming apparatus comprising: an image forming control unit configured to form an image by the head based on a plurality of packets successfully received by the packet receiving unit. The image according to claim 1, wherein the specific information storage unit stores, for each packet of the print data, a flag management table that stores an essential determination flag indicating whether the packet is a packet corresponding to an essential image region. Forming equipment. A plurality of the heads, and a plurality of head controllers that transmit data for the heads in the print data to at least one or more of the heads,
The packet receiving means and the packet determining means are provided in each of the head controllers,
When the packet determination unit determines that the packet is a packet corresponding to an essential image region, the packet determination unit further includes a stop control unit that stops transmission of the print data to the head by all other head controllers. The image forming apparatus according to claim 1 or 2. The packet transmitting means transmits the packet by sequentially transmitting data of a predetermined length as a unit,
The packet receiving means sequentially receives the data of the predetermined length,
A ring buffer having the same storage capacity as the data amount of the packet;
Storage means for sequentially storing the data of the predetermined length received by the packet receiving means in a storage area in the ring buffer;
First area information indicating whether or not the first storage area of the ring buffer is a storage area for storing next data, and a storage state indicating whether or not data is stored in the last storage area of the ring buffer Receiving determination means for determining whether or not the reception of the packet is successful based on the information,
The packet determining means transmits the same packet a predetermined number of times by the packet transmitting means, but if the reception determining means does not determine that the packet has been successfully received, the packet is determined to be indispensable. The image forming apparatus according to claim 1, wherein the image forming apparatus determines whether the packet corresponds to an image area. 5. The apparatus according to claim 1, further comprising notification means for notifying the external device that an error has occurred when it is determined that the packet is an essential image area. 6. Image forming apparatus. A plurality of the heads, and a plurality of head controllers that transmit data for the heads in the print data to at least one or more of the heads,
The packet receiving means and the packet determining means are provided in each of the head controllers,
The image forming apparatus according to claim 5, wherein the notification unit transmits identification information indicating the head controller in which the error has occurred to the external apparatus. A processing unit that creates and transmits print data, and a packet having a predetermined data length in at least a part of a path from the print data received from the processing unit to a head for forming an image. In an image forming system comprising an image forming apparatus that transmits as
The processor is
Essential image area determining means for determining an image area essential for image formation of an image corresponding to the print data;
Specific information transmitting means for transmitting specific information for specifying the packet in the print data corresponding to the determined essential image area to the image forming apparatus;
Print data transmission means for transmitting the print data to the image forming apparatus,
The image forming apparatus includes:
Specific information storage means for storing the specific information;
Packet transmission means for transmitting the print data in units of the packet;
A packet receiving means for receiving the packet;
Even if the packet transmission means transmits the packet a predetermined number of times, if the packet reception means does not succeed in receiving the packet, the packet corresponds to the essential image area based on the specific information. A packet determination means for determining whether the packet is a packet;
When it is determined that the packet is not a packet corresponding to an indispensable image area, a transmission control unit that causes the packet transmission unit to transmit a packet in the next order;
An image forming system comprising: an image forming control unit configured to form an image by the head based on a plurality of packets successfully received by the packet receiving unit. An image forming method by an image forming apparatus that transmits print data received from an external device in units of a packet having a predetermined data length in at least a part of a route until the print data is supplied to a head for forming an image,
A storage step of storing in a specific information storage unit of the image forming apparatus for storing specific information for specifying a packet corresponding to an image region essential for image formation in the print data;
A packet transmission step in which a packet transmission unit of the image forming apparatus transmits the print data in units of the packet;
A packet receiving step in which the packet receiving means of the image forming apparatus receives the packet;
The packet determination unit of the image forming apparatus, when the packet transmission unit does not successfully receive the packet even if the packet transmission unit transmits the packet a predetermined number of times, based on the specific information, A packet determination step of determining whether the packet is a packet corresponding to the essential image region;
A transmission control step for causing the packet transmission unit to transmit a packet in the next order when the transmission control unit of the image forming apparatus determines that the packet is not a packet corresponding to an essential image region;
An image forming method comprising: an image forming control step in which an image forming control unit of the image forming apparatus forms an image with the head based on a plurality of packets successfully received by the packet receiving unit.

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