JP4380168B2 - Image data transmission control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention provides one-way communication of image data between an image output processing device that executes predetermined image output processing based on received image data and an image data supply device that transmits image data to the image output processing device. The present invention relates to an image data transmission control device.
[0002]
[Prior art]
  The image data transmission control device described above is capable of full-duplex communication for transmitting and receiving control data between the printer controller and the printer engine between a printer engine that outputs an image and a printer controller that drives and controls the printer engine. LVDS (Low Voltage Differential Signaling) system, which is a kind of differential data transmission system that transfers image data in one direction from the printer controller to the printer engine separately from the communication line, Some have adopted a transmission module and are provided with a communication line capable of transferring image data at high speed. In other words, it is installed on the printer controller side as an image data supply device, installed on the printer engine side as an image output processing device, and a first data transmission unit that converts image data into serial data of a predetermined length and sequentially outputs it. The first data transmission / reception means including the first data reception unit that receives the serial data transmitted from the first data transmission unit and converts the serial data into parallel data is configured by adopting the above-described LVDS method or the like. is there.
[0003]
[Patent Document 1]
  JP 2002-254663 A
[0004]
[Problems to be solved by the invention]
  However, the above-described conventional image data transmission control device unilaterally transfers image data from the image data supply device to the image output processing device by a one-way communication method. The transmission protocol has the advantage that it can be configured at high speed and at low cost, but when image data transfer is started from the image data supply device, data is unilaterally sent until all data is transferred. In the data processing by software executed by the control unit on the image output processing device side, there is a problem that it is necessary to provide a large-capacity buffer memory in order to avoid overflow of data, resulting in an increase in cost. In particular, in recent years, in the case of a photographic image that requires a high-definition output image, the amount of image data is increased, which is a significant problem.
[0005]
  Conversely, if the capacity of the buffer memory is limited, it is necessary to execute data processing by software on the buffered image data before the buffer memory overflows, and other necessary processing is not interrupted during that time. There is a problem that the throughput of the image output processing device is reduced.
[0006]
  Here, if the image data transmission control device adopts a full-duplex communication method and performs transfer while handshaking each time image data is transferred, the above problem can be solved, but if an inexpensive system is used, the communication speed On the contrary, the throughput (for example, print processing time) as the image output processing apparatus is reduced.
[0007]
  The present invention has been made in view of the above-described conventional problems. The cost performance and performance of the image output processing apparatus are adopted while adopting a one-way communication method in which a data transmission protocol can be easily constructed and configured at low cost. The present invention is to provide an image data transmission control device that does not reduce the image quality.
[0008]
[Means for Solving the Problems]
  In order to achieve the above-described object, the characteristic configuration of the image data transmission control device according to the present invention is the same between the image output processing device and the image data supply device as described in claim 1 in the claims. An image output processing device that is provided separately from a control data transmission control device that communicates in a bidirectional manner and that executes predetermined image output processing based on received image data, and image data supply that transmits image data to the image output processing device An image data transmission control device that performs one-way communication of image data with a device using only a clock signal line and a serial transmission line, and is installed on the image data supply device side to store image data for one page. A first data transmission unit that converts serial data of a predetermined length and sequentially outputs the serial data in synchronization with the clock signal transmitted through the clock signal line via the serial transmission line; First data transmission / reception comprising a first data receiving unit installed on the image output processing device side and sequentially receiving serial data transmitted from the first data transmitting unit in synchronization with the clock signal and converting the serial data into parallel data Means and the image output processing device sideA second data transmission unit configured to transmit a transmission preparation signal for requesting to stop transmission of image data during reception of the image data; and a second data transmission unit disposed on the image data supply device side to receive the transmission preparation signal. Consisting of two data receiversSecond data transmission / reception means, the first data transmission unit,Even during image data transmissionSecond dataDepending on the receiverSend ready signalWhen you receiveThe point is that transmission of image data is stopped.
[0009]
  According to the above configuration, the image data can be transmitted from the first data transmission unit of the image data supply device to the first data reception unit of the image output processing device by one-way communication., PaintingImage output processor sideFrom the second data transmitterImage data supply deviceTo the second data receiverReady signal is sentWhen the second data receiving unit receives the transmission preparation signal,One data transmitterWill stop sending image data even during image data transmission,Transmission of voluntary image data can be stopped based on the state on the image output processing device side, and various processing can be performed without fear of overflowing image data without providing a large-capacity buffer memory. The degree of freedom increases.
[0010]
  In the second feature configuration, as described in claim 2 of the same column, in addition to the first feature configuration described above, the image output processing device processes image data received by the first data receiving unit. A transmission preparation signal generating means for generating the transmission preparation signal based on the state is provided.
[0011]
  The job of the image output processing device is aggregated into the reception processing of the image data transmitted from the image data supply device and the output processing of the received image data. In either case, since the transmission preparation signal can be generated based on the processing state, the throughput of the apparatus can be improved without fear of overflowing image data without providing a large-capacity buffer memory.
[0012]
  In the third feature configuration, as described in claim 3 of the same column, in addition to the second feature configuration described above, the image output processing device converts the image data received by the first data receiving unit into an image. A FIFO buffer memory that stores and expands the data in the memory, and the transmission preparation signal generation means does not involve the transmission preparation signal based on the storage state of the image data in the buffer memory. The configuration is such that it is generated by a hardware circuit.
[0013]
  As a result, the software intervenes to check the storage state of the image data in the buffer memory that temporarily stores the received image data, and to generate a transmission preparation signal when there is a possibility of overflowing the image data. Therefore, the software can execute other predetermined jobs regardless of the reception processing state of the image data, so that the throughput of the entire apparatus can be improved.
[0014]
  In the fourth feature configuration, as described in claim 4 of the same column, in addition to the third feature configuration described above, the transmission preparation signal generating means generates the transmission preparation signal based on the remaining capacity of the buffer memory. The transmission preparation signal is generated when all the image data received after reaching a predetermined capacity writable in the buffer memory.
[0015]
  That is, even if a transmission preparation signal is generated and a request to stop transmission of image data is made, transmission of image data does not stop immediately, but a time difference occurs. Therefore, if the transmission preparation signal is generated when all the image data received after generating the transmission preparation signal has a predetermined capacity writable in the buffer memory, the overflow of the image data is prevented. It can be surely prevented.
[0016]
  In the fifth feature configuration, in addition to any of the first to fourth feature configurations described above, the first data transmission / reception means is configured to generate an image by a differential data transmission method. In the point that the data is unidirectionally communicated, and the sixth feature configuration is the same as the sixth feature configuration described above, in addition to the fifth feature configuration described above, the second data transmitting / receiving means includes: The transmission preparation signal is unidirectionally communicated by a differential data transmission method.
[0017]
  By adopting the above configuration, high-speed transfer of image data can be realized at low cost and with high accuracy.
[0018]
  In order to achieve the above object, the characteristic configuration of the image output processing device according to the present invention is transmitted from the image data supply device via the image data transmission control device having any one of the first to sixth characteristic configurations described above. Output processing device for receiving processed image dataIs provided separately from the control data transmission control device that performs two-way communication between the image output processing device and the image data supply device, and receives image data using only the clock signal line and the serial transmission line. And a second data transmission unit that transmits a transmission preparation signal for requesting stop of transmission of the image data during reception of the image data.
[0019]
  In order to achieve the above-described object, the image data supply device according to the present invention is configured such that the image output processing device has an image via the image data transmission control device having any one of the first to sixth feature configurations described above. Image data supply device that transmits dataIs provided separately from the control data transmission control device that performs bidirectional communication between the image output processing device and the image data supply device, and converts image data for one page into serial data of a predetermined length. A first data transmission unit that sequentially outputs in synchronization with a clock signal transmitted through the clock signal line via the serial transmission line, and a request to stop transmission of the image data transmitted from the image output processing device. A second data receiving unit that receives a transmission preparation signal, and the first data transmission unit is configured to stop transmission of image data upon reception of the transmission preparation signal.In the point.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
  An image data transmission control apparatus according to the present invention will be described below with reference to the drawings. As shown in FIG. 1, an inkjet printer 3 which is an example of an image forming apparatus as an image output processing apparatus that executes predetermined image output processing based on received image data, and image data is transmitted to the image output processing apparatus. An image output processing system is configured by connecting a host computer 1 as an image data supply apparatus via an interface unit 2.
[0021]
  As shown in FIG. 2, the inkjet printer 3 stores a roll-shaped recording paper 311 as a recording medium, and supplies a recording paper storage unit 310 that feeds a set amount and a recording paper fed from the recording paper storage unit 310. An image recording unit 320 that visualizes an image by ejecting ink on paper 311 based on image data, and a paper discharge unit 330 that cuts and outputs the recording paper 311 recorded by the image recording unit 320 to a predetermined length. Each of the functional blocks including a recording paper transport unit 340 that transports the recording paper 311 fed from the recording paper storage unit 310 to the image recording unit 320 and the paper discharge unit 330, and printer control for controlling the operation of the functional blocks. The part 350 is provided in a housing 360 covered with a case.
[0022]
  The recording paper storage unit 310 includes a pair of rollers 312 and 313 including a driving roller 312 and a driven roller 313 in which a long recording paper 311 wound around a roll cassette 314 detachably attached to a case is rotatable forward and backward. The recording paper 311 is fed from the recording paper storage unit 310 toward the image recording unit by driving the driving roller 312 in the normal direction, and wound around the roll cassette 314 by driving in the reverse direction.
[0023]
  The recording paper transport unit 340 includes a driving roller and a driven roller having a one-way clutch that transports the recording paper 311 fed from the recording paper storage unit 310 toward the image recording unit 320 and the paper discharge unit 330. The first pressure roller unit 341 disposed on the upstream side of the image recording unit 320 in the recording paper conveyance direction, the second pressure roller unit 342 disposed on the downstream side of the image recording unit 320 in the recording paper conveyance direction, and the image recording unit 320. And a suction conveyance unit 343 that sucks the recording paper 311 during image recording from the back surface and keeps the distance between the image recording unit 320 and the recording paper 311 constant.
[0024]
  The suction conveyance unit 343 is arranged along a substantially horizontal recording paper conveyance surface, and records by sucking air from a suction plate 344 having a large number of circular suction holes and suction holes formed in the suction plate 344. A suction fan 345 for bringing the paper 311 into close contact with the suction plate 344 and an exhaust duct 346 for exhausting air sucked by the suction fan 345 are provided below the suction plate 344.
[0025]
  As shown in FIGS. 2 and 3, the image recording unit 320 includes an ink cartridge 321 containing black inks of black (K) and light black (LK), cyan (C), light cyan (LC), As an image recording element for mounting a color ink cartridge 322 containing ink of five colors, magenta (M), light magenta (LM), and yellow (Y), and ejecting ink supplied from each ink cartridge below. A carriage 323 as an image recording head having a plurality of piezoelectric ink jet nozzles 324 and a drive mechanism for main-scanning the carriage 323 in the recording paper width direction orthogonal to the conveyance direction of the recording paper 311 are provided.
[0026]
  The drive mechanism includes a slide shaft 329 that holds the carriage 323 so as to be slidable along the paper width direction of the recording paper 311, a carriage motor 325 installed on one end side of the recording paper 311 in the paper width direction, and a drive thereof. A driving pulley 326 fixed to the shaft, a driven pulley 327 installed on the other end side, and an endless belt 328 stretched between the pair of pulleys. By fixing the carriage 323 to the endless belt 328, The carriage 323 is configured to be reciprocally driven in the main scanning direction.
[0027]
  As shown in FIG. 2, the paper discharge unit 330 discharges the cut recording paper 311 and a cutting unit 331 that cuts the recording paper 311 conveyed by the first and second pressure roller units 341 and 342 in a predetermined size. And a paper discharge roller unit 334 in which a driven roller 335 and a driven roller 336 are pressure-bonded. In the cutting unit 331, the moving blade 332 and the fixed blade 333 are arranged vertically with the recording paper 311 in between, and the recording paper 311 is cut along the width direction by operating the moving blade 332 downward from above. To do.
[0028]
  As shown in FIG. 1, the printer control unit 350 stores a CPU 4 as a controller that controls each functional block of the printer described above, a ROM 5 that stores an execution program of the CPU 4, and various control data and setting data. RAM 6, input / output control unit 9 for individually controlling each functional block, printer-side interface unit 7 for transmitting / receiving the print data and control data to / from the host computer 1, and timing for driving the image recording element A timing generation unit 19 that outputs a signal and a print buffer 10 that stores one line of image data by one main scan of the image recording head are connected by an internal bus.
[0029]
  The input / output control unit 9 drives an input / output control CPU 900 having a built-in or external ROM or RAM to drive a carriage motor 325 to perform main scanning of the image recording head 323, and an image recording head 323. An encoder device 12 to detect the position in the main scanning direction, a timer circuit 13 for measuring the cycle of the encoder device 12, a feed roller 312 for feeding, pressure roller units 341 and 342 for transport, and a discharge roller A motor driver circuit 15 that controls a drive motor that operates each drive roller of the unit 334, a motor driver circuit 16 that drives the suction fan 345, a motor driver circuit 17 that drives the cutting unit 331, and a roll cassette 314 Detection values of various sensors such as paper sensors that detect the presence or absence of recording paper It is constructed provided with a sensor input circuit 18 for inputting.
[0030]
  The host computer 1 has various image recording media such as document file data and image file data generated by various application programs executed under the management of the operating system, and memory cards such as CD, DVD, compact flash, and memory stick. For image file data read from, color separation processing for converting RGB data to CMY data, black extraction processing for extracting black from CMY data and converting it to CMYK data, and correction of color and gradation A printer driver unit 1a for converting the print data into seven colors (K, LK, C, LC, M, LM, Y) suitable for the inkjet printer 3 and generating printer control data for the inkjet printer 3; , Printer driver The print data and printer control data as conversion processing image data 1a is output to the ink-jet printer 3, are provided with a host interface unit 200 for receiving a control state data from the ink-jet printer 3.
[0031]
  As shown in FIG. 4, the host-side interface unit 200 and the printer-side interface unit 7 transmit an image data transmission control device that performs one-way communication of print data, and transmit printer control data to the inkjet printer 3. The control data transmission control device that receives the control state data is separated from the control data transmission control device, thereby realizing high-speed and low-cost transmission of print data.
[0032]
  The control data transmission control device performs two-way communication with a control data transmission / reception unit 204 installed in the host-side interface unit 200 and a control data transmission / reception unit 701 installed in the printer-side interface unit 7 using an optical cable connecting them. The control data transmission / reception unit 204 is connected to the printer driver unit 1a via the PCI bus, and the control data transmission / reception unit 701 is connected to the printer control unit 350. The ARCNET (Attached Resource Computer Network: LAN protocol of the improved token passing system) is used. Connected to internal bus. The inkjet printer 3 executes a printing operation in response to a print command including print size data and print number data from the printer driver 1a of the host computer 1 via the control data transmission control device, while the inkjet printer 3 runs out of paper. The printer driver 1a is informed of various states such as ink out of ink.
[0033]
  The image data transmission control device performs one-way communication using an LVDS (Low Voltage Differential Signaling) method to transmit print data to the inkjet printer 3, and is a printer driver obtained via a PCI bus. An image data transmission side LVDS control unit 201 that generates and outputs 21-bit parallel transmission data obtained by adding 5 bits of communication control data to 16-bit print data from 1a, and 21 bits from the image data transmission side LVDS control unit 201 Are transmitted from the LVDS driver 202 to the first data transmission units 201 and 202 including the LVDS driver 202 that converts the transmission data into 7-bit × 3 serial data and outputs the serial data to the inkjet printer 3 in synchronization with a clock having a predetermined frequency. An LVDS receiver 702 that receives real data and converts it into 21-bit parallel data, and an image data receiving side LVDS control unit 704 that sequentially transfers 16-bit print data to a DMA write control unit 705 (to be described later) based on the communication control data. A first data receiving unit 702, 704, an LVDS driver 703 that converts 21-bit transmission data into 7-bit × 3 serial data and outputs the data to the host computer 1 in synchronization with a clock of a predetermined frequency; Second data transmission units 703 and 704 including an image data reception side LVDS control unit 704 that outputs a transmission preparation signal input from the DMA write control unit 705 to the driver 703, and serial data from the LVDS driver 703 are received. L to convert to 21-bit parallel data It comprises a second receiver 201 and 203 comprising a DS receiver 203 and an image data transmission side LVDS controller 201 that receives a transmission preparation signal described later and stops inputting new image data to the LVDS driver 202. is there.
[0034]
  That is, first data transmission units 201 and 202 that are installed on the host computer 1 side as an image data supply device, convert print data as image data into serial data of a predetermined length and sequentially output the data, and an image output processing device The first data transmission / reception comprising the first data receiving units 702 and 704, which are installed on the ink jet printer 3 side, receive serial data transmitted from the first data transmitting units 201 and 202, and convert the parallel data into parallel data. Means 201, 202, 702, 704, and transmission of image data to the host computer 1 side according to a predetermined processing state of image data installed on the inkjet printer 3 side and received by the first data receiving units 702, 704 Second data transmission units 703 and 704 for transmitting a transmission preparation signal for requesting stoppage, Second data including second data receiving units 201 and 203 that are installed on the side of the computer 1 and transmit the transmission preparation signal READY transmitted from the second data transmitting units 703 and 704 to the first data transmitting units 201 and 202. The image data transmission control apparatus is configured to include transmission / reception means 703, 704, 201, and 203.
[0035]
  The printer-side interface unit 7 further includes a FIFO buffer memory 706 of 512 words × 64 bits capacity for temporarily storing print data received by the image data receiving side LVDS control unit 704, and data to the buffer memory 706. A DMA write control unit 705 that performs write control, a DMA read control unit 707 that performs read control of data from the buffer memory 706, and print data read by the DMA read control unit 707 is written into the 256 megabyte SDRAM 8, or the SDRAM 8 An SDRAM control unit 708 for reading out the written print data is provided.
[0036]
  The FIFO buffer memory 706 includes a programmable gate array FPGA that can be developed using VHDL, which is a kind of hardware description language, together with the peripheral circuits 704, 705, 707, and 708 described above, and a DMA write control unit 705. When the remaining data capacity that can be written by the memory reaches a predetermined remaining capacity that can be written in the range of the full buffer memory capacity, for example, 16 words, a near full flag (Nearly FF) as a transmission preparation signal READY source is set. Transmission preparation signal generating means for setting and outputting to the DMA write control unit 705 is provided.
[0037]
  That is, the transmission preparation signal generating unit generates the transmission preparation signal READY based on the processing state of the image data received by the first data receiving units 702 and 704, and stores the image data in the buffer memory 706. The transmission preparation signal READY is generated based on the state. Here, the small remaining capacity that can be written within the range of the full buffer memory capacity means that the remaining capacity of the buffer memory 706 sets (turns on) the near full flag (Nearly FF) or is ready for transmission. All image data received after transmitting the signal READY is a predetermined capacity writable in the buffer memory 706, and can be set as appropriate depending on the data transfer speed, the writing to the buffer memory 706, and the reading speed.
[0038]
  After the near full flag (Nearly FF) is set, the buffer memory 706 advances the data read process by the DMA read control unit 707, and when the remaining capacity exceeds the predetermined capacity, the near full Reset the flag (Nearly FF). Here, the set near-full flag (Nearly FF) may be reset immediately when the remaining capacity becomes equal to or greater than the predetermined capacity, but the remaining capacity of several words increases from the predetermined capacity in anticipation of a margin. It may be reset at that time. The remaining capacity of the buffer memory 706 can be easily grasped by processing such as calculating the relative value of the write address and the read address.
[0039]
  A transmission sequence of print data transmitted by the above-described image data transmission control apparatus will be described. The print data is composed of 2-bit data for one pixel, and is composed of a set of data for one page of print size corresponding to each color (seven colors) in a predetermined order for each line in units of 8 pixels and 16 bits. As shown in FIG. 5, the print data is assigned to 16-bit data from data bits D0 to D15 with data bits D0 to D19 as transmission data and data bit D20 as reception data, and the data bits D16 to D17 are assigned to 2 bits. The color control data PxF0 and PxF1 shown in FIG. 6 are allocated, the transmission control data TxC0 and TxC1 shown in FIG. 7 are allocated to the 2 bits of the data bits D18 to D19, and the READY signal (this is the transmission preparation signal described above). As a function).
[0040]
  In the color control data PxF0 and PxF1, the data “00” indicates no image data, the data “10” indicates the color data start, the data “01” indicates the color data end, and each color data is stored in a predetermined order. Send. The transmission control data TxC0 and TxC1 indicate that data “00” is idle, data “10” starts data transfer, data “01” is valid data transfer, and data “11” indicates data transfer end.
[0041]
  When the image data transmission side LVDS control unit 201 sets data in the data bits D0 to D19 and outputs the data to the LVDS driver 202, the LVDS driver 202 converts the received data into 7-bit × 3 serial data as described above. The data is converted and transmitted to the LVDS receiver 702 in synchronization with the transfer clock through the three serial transmission lines. The LVDS receiver 702 converts the received serial data into parallel data and outputs the parallel data to the LVDS control unit 704.
[0042]
  On the other hand, the image data receiving side LVDS control unit 704 performs transfer processing to the DMA write control unit 705 each time it receives 16-bit print data identified based on the color control data PxF0, PxF1 and the transmission control data TxC0, TxC1. On the other hand, when the fact that the near full flag (Nearly FF) is set by the buffer memory 706 is recognized through the DMA write control unit 705, the transmission preparation signal READY is negated to the data bit D20 (reset, other data bits are used) But is always reset) and transmitted to the LVDS receiver 203 via the LVDS driver 703.
[0043]
  The image data transmission side LVDS control unit 201 recognizes that the reception side is in a data receivable state when the transmission preparation signal READY is asserted (set), and when the transmission preparation signal READY is negated, the image data transmission side LVDS control unit 201 As soon as it recognizes that the preparation signal READY has been negated, the transmission is stopped, and it waits until the transmission preparation signal READY is asserted. That is, the first data transmission units 201 and 202 are configured to stop transmission of image data in response to reception of the transmission preparation signal READY by the second data reception units 201 and 203.
[0044]
  As described above, since the transmission preparation signal generating means is configured by hardware regardless of the operation of the CPU that controls the operation of the functional blocks of the inkjet printer 3, it does not hinder the operation of the inkjet printer 3 itself. The printing process described later can be executed at a predetermined printing speed.
[0045]
  Below, the image output processing process by the inkjet printer 3 is demonstrated. As described above, the inkjet printer 3 that receives the print command from the host computer 1 by the control data transmission control device adopting the ARCNET and the print data from the image data transmission control device adopting the LVDS method is shown in FIGS. 2, the following predetermined image output process is executed under the control of the CPU 4 that executes the control program stored in the ROM 5.
[0046]
  The drive roller 312 of the recording paper storage unit 310 is driven to rotate forward to feed the recording paper 311, and is conveyed to the image recording unit 320 by the first pressure roller unit 341 of the recording paper conveyance unit 340. When the leading edge of the recording paper reaches the print start position of the image recording unit 320, recording is performed by ejecting ink from a predetermined inkjet nozzle based on data from the recording head driver circuit 11 while the carriage 323, which is an image recording head, performs main scanning. An image is formed on the surface of the paper 311. The recording paper 311 is intermittently driven by a predetermined amount synchronized with the main scanning of the carriage 323 by the first pressure roller 341 and sub-scanned in the transport direction.
[0047]
  In the main scanning direction of the image recording head 323, a long encoder film 401 having slits formed at equal intervals with a density of 180 per inch is extended and scanned together with the image recording head 323. The timing sensor 19 detects the slit of the encoder and generates a pulse signal. The timing generator 19 includes a time T from the rising edge of the encoder pulse signal input via the input / output control CPU 900 to the next rising edge. Is counted by a timer circuit 13 (or a timer circuit provided in a separate timing generation unit) over several cycles, and an average value of one cycle T of encoder pulses is calculated and derived. The calculated cycle T is used as a unit control cycle, multiplied by a predetermined multiplication number stored in the timing generation unit 19, here multiplied by 8 to calculate and derive the multiplication cycle of the drive timing signal, and the calculated multiplication cycle data is A drive timing signal is generated by outputting the print head driver circuit 11 that controls ink ejection via the print buffer 10.
[0048]
  A pulse voltage applied to the piezoelectric element for driving the ink jet nozzle based on the print data for one main scanning line transferred from the SDRAM 8 to the print buffer 10 is recorded on the recording paper by the paper edge detection sensor 355 separately disposed on the recording head 323. From the paper edge detection time 311, the image is output in synchronization with the rising edge of the drive timing signal, and an image with a desired resolution is formed. According to this embodiment, a resolution of 180 DPI × 8 = 1440 DPI can be obtained.
[0049]
  When the image output for one sheet on the recording paper 311 is completed, the first and second pressure roller units 341 and 342 and the paper discharge roller unit 334 are driven, and the recording paper 311 is conveyed to the cutting position by the cutting unit 331. The paper is stopped, cut to a predetermined size, and then discharged by the paper discharge roller unit 334. The remaining recording paper 311 is driven in reverse by the driving roller 312 of the recording paper storage unit 310 and the leading edge of the recording paper is wound up to a predetermined position to prepare for the next image output processing process.
[0050]
  Another embodiment will be described below.
  In the above-described embodiment, the transmission preparation signal generating unit is configured to transmit the transmission preparation signal when all the image data received after the remaining capacity of the buffer memory generates the transmission preparation signal becomes a predetermined capacity writable in the buffer memory. Having described the hardware circuit that generates the signal, but based on the broader concept of the present invention, a part or the main part of the data reception process is the software that controls other functional blocks of the image output processing device. It may be configured to be executable in part and configured to generate a transmission preparation signal by the software. That is, a transmission preparation signal is generated when there is a possibility that another output process overlaps during the data reception process by the software and data overflow occurs.
[0051]
  In the above-described embodiment, the first data transmitting / receiving unit and the second data transmitting / receiving unit adopt the LVDS method. However, the first data transmitting / receiving unit is not limited to the LVDS method as long as the differential data transmission method is used. In addition to the differential data transmission method, an optical transmission module may be adopted. Furthermore, the second data transmission / reception means is not limited to the one based on the LVDS system, but may be one that transmits a signal with a voltage value using a single signal line. Further, although the LVDS driver circuit that transmits 7 bits × 3 serial transmission lines in synchronization with the clock has been described, the number of transmission lines and the length of serial data may be set as appropriate.
[0052]
  In the embodiment described above, the FIFO buffer memory 706 is configured with a programmable gate array FPGA that can be developed using VHDL, which is a kind of hardware description language, together with peripheral circuits 704, 705, 707, and 708. In the above description, the transmission preparation signal generating means is realized as a partial circuit of the gate array. However, the configuration of the hardware circuit is not limited to this and is appropriately configured using a known circuit configuration technique. It is possible.
[0053]
  In the above-described embodiment, an inkjet printer is used as an image output processing device and a host computer is used as an image data supply device. However, the image output processing device is not limited to an inkjet printer, and a laser beam printer or photographic paper can be used as a photograph. The present invention can be applied to an image output processing apparatus such as a photographic processing apparatus that exposes image data with a digital exposure head and develops and outputs it. The image data supply apparatus is not limited to a host computer, and image information is digitally transmitted from photographic film. The present invention can be applied to a printer controller such as an image processing apparatus that reads data as data, performs predetermined image processing, and outputs print image data to the above-described image output processing apparatus. In this specification, for bidirectional communication in which the transmission side and the reception side perform transmission / reception via an acknowledge signal each time unit data is transmitted / received, data is transmitted from the transmission side unilaterally or irregularly. A communication method for sending a communication permission signal only from the receiving side is defined as one-way communication in a broad sense.
[0054]
【The invention's effect】
  As described above, according to the present invention, an image that does not deteriorate the cost performance and performance of the image output processing apparatus while adopting a one-way communication method that allows a data transmission protocol to be easily constructed and configured at low cost. A data transmission control device can be provided.
[Brief description of the drawings]
FIG. 1 is a control block diagram of an image output processing apparatus according to the present invention.
FIG. 2 is a functional block configuration diagram of an image output processing apparatus according to the present invention.
FIG. 3 is a perspective view of a main part.
FIG. 4 is a circuit block diagram of the main part.
FIG. 5 is an explanatory diagram of transmission data.
FIG. 6 is an explanatory diagram of color control data.
FIG. 7 is an explanatory diagram of transmission control data.
[Explanation of symbols]
1: Image data supply device (host computer)
3: Image output processing device (inkjet printer)
201, 202: first data transmission unit
702, 704: first data receiver
201, 203, 703, 704: second data transmission / reception means
READY: Transmission preparation signal

Claims (8)

An image output processing device that is provided separately from the control data transmission control device that performs bidirectional communication between the image output processing device and the image data supply device, and that executes predetermined image output processing based on the received image data; An image data transmission control device that performs one-way communication of image data using only a clock signal line and a serial transmission line with an image data supply device that transmits image data to the image output processing device,
Installed on the image data supply device side, converts image data for one page into serial data of a predetermined length, and sequentially outputs it in synchronization with the clock signal transmitted through the clock signal line via the serial transmission line. A first data transmission unit configured to receive the serial data transmitted from the first data transmission unit in synchronization with the clock signal and convert the serial data to parallel data. A first data transmitting / receiving means comprising a receiving unit;
A second data transmission unit installed on the image output processing device side for transmitting a transmission preparation signal for requesting to stop transmission of image data during reception of the image data; and installed on the image data supply device side for transmitting the data A second data transmitting / receiving means comprising a second data receiving unit for receiving a preparation signal ;
The first data transmission unit is configured to stop transmission of image data when receiving a transmission preparation signal by the second data reception unit even during transmission of image data. .   The image data transmission control according to claim 1, wherein the image output processing device includes transmission preparation signal generation means for generating the transmission preparation signal based on a processing state of image data received by the first data receiving unit. apparatus.   The image output processing device includes a FIFO type buffer memory that develops and stores the image data received by the first data receiving unit in an image memory, and the transmission preparation signal generation unit is configured to transmit the image data to the buffer memory. 3. The image data transmission control device according to claim 2, wherein the transmission preparation signal is generated by a hardware circuit not including control software of the image output processing device based on a storage state.   The transmission preparation signal generating means outputs the transmission preparation signal when all the image data received after the remaining capacity of the buffer memory generates the transmission preparation signal reaches a predetermined capacity writable in the buffer memory. The image data transmission control device according to claim 3 to be generated.   5. The image data transmission control device according to claim 1, wherein the first data transmission / reception means performs one-way communication of image data by a differential data transmission method.   6. The image data transmission control device according to claim 5, wherein the second data transmission / reception means performs one-way communication of the transmission preparation signal by a differential data transmission method. An image output processing equipment for receiving image data transmitted from the image data supply device via the image data transmission control apparatus according to any one of claims 1-6,
First data reception that is provided separately from the control data transmission control device that performs bidirectional communication between the image output processing device and the image data supply device, and that receives image data using only the clock signal line and the serial transmission line. And a second data transmission unit that transmits a transmission preparation signal for requesting to stop transmission of the image data during reception of the image data. An image data supplying equipment for transmitting the image data to the image output processing apparatus via an image data transmission control apparatus according to any one of claims 1 to 6,
Provided separately from the control data transmission control device that performs two-way communication between the image output processing device and the image data supply device, converts image data for one page into serial data of a predetermined length, and serial transmission A first data transmission unit that sequentially outputs in synchronization with a clock signal transmitted through a clock signal line, and a transmission preparation signal that requests to stop transmission of the image data transmitted from the image output processing device. An image data supply apparatus comprising a second data receiving unit for receiving, wherein the first data transmitting unit is configured to stop transmitting image data when receiving a transmission preparation signal.

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