JP4812003B2 - Print data transfer method and recording apparatus - Google Patents

Description

  The present invention relates to a print data transfer method and a recording apparatus for transferring print data transmitted to a carriage by a conveyance clock to a print head.

  FIG. 8 is a block diagram showing an example of the configuration of a conventional recording apparatus, and FIG. 9 is a block diagram showing the configuration of the print data control unit 122 shown in FIG.

  As shown in FIG. 8, the conventional example is a printer 101 connected to a host apparatus 102, and a main control unit 110 that controls the entire printer 101 and ink droplets are ejected onto a recording medium to form an image. Print head 130, carriage 120 on which print head 130 is mounted and controlling print head 130, linear encoder 140 for detecting the position of carriage 120, and edge sensor 150 for detecting the end of the recording medium Is provided.

  The carriage 120 includes a CPU bus interface 121 for transmitting / receiving data to / from a CPU (not shown) of the main control unit 110, and a trigger signal TRIG according to the position of the carriage 120 detected by the linear encoder 140. In addition, the ejection signal generation unit 123 that outputs the ejection signal FIRE and the print data DATA transmitted from the main control unit 110 are temporarily accumulated, and at a timing according to the trigger signal TRIG output from the ejection signal generation unit 123. A print data control unit 122 that transmits to the print head 130 as head data HD-DATA, a D / A converter 124, and an A / D converter 125 are provided.

  As shown in FIG. 9, the print data control unit 122 temporarily stores the print data DATA transmitted from the main control unit 110, and the timing according to the trigger signal TRIG output from the ejection signal generation unit 123. The head timing controller 170 outputs a read enable signal RDEN to the FIFO 160. The print data DATA accumulated in the FIFO 160 is printed at the print timing according to the read enable signal RDEN output from the head timing controller 170. Data HD-DATA is transmitted to the printer head 130.

  The operation of the printer 101 configured as described above will be described below.

  10A and 10B are diagrams for explaining the operation of the printer 101 shown in FIGS. 8 and 9. FIG. 10A is a diagram showing the flow of print data, and FIG. 10B is a print state on the recording medium in the printer head 130. FIG.

  As shown in FIG. 10A, in the printer 101 shown in FIGS. 8 and 9, the print data DATA given to the main control unit 110 by the command from the host device 102 is carried by the carry clock CLOCK. 10 pieces corresponding to the number of nozzles of the print head 130 are continuously incorporated into the continuous data and transmitted to the carriage 120. Further, the main control unit 110 transmits a print data valid signal VALID indicating the print data DATA among the continuous data together with the carrier clock CLOCK and the print data DATA. This print data valid signal VALID is synchronized with the carrier clock CLOCK, and among the continuous data transmitted from the main control unit 110, “1” at the timing when it becomes the print data DATA, and “0” at other timings. Thus, the print data DATA is shown.

  The print data DATA transmitted to the carriage 120 in this way is recognized by the print data control unit 122 by the print data valid signal VALID, and only the print data DATA among the continuous data transmitted from the main control unit 110 is conveyed. It is written in the FIFO 160 according to the clock CLOCK.

  In the FIFO 160, ten pieces of print data DATA continuously incorporated in the continuous data transmitted from the main control unit 110 are continuously accumulated. That is, in the example shown in FIG. 10, the print data DATA 1 to 10, the print data DATA 11 to 20, the print data DATA 21 to 30, and the print data DATA 31 to 40 are continuously stored in the FIFO 160. .

  Thereafter, when the read enable signal RDEN is output from the head timing controller 170, the print data DATA accumulated in the FIFO 160 is transmitted to the print head 130 as continuous head data HD-DATA, as shown in FIG. 10B. An image is formed on the recording medium.

  In the printer 101 as described above, the main control unit 110 and the carriage 120 are electrically connected by a flexible flat cable, and the above-described carrier clock CLOCK, print data DATA, and print data valid signal VALID are the flexible flat cable. Is transmitted from the main control unit 110 to the carriage 120 via. Further, when the carriage 120 slides and the printer 101 is a large one, the distance between the main control unit 110 and the carriage 120 becomes long, so that the length of the above-described flexible flat cable is 4 m or the like. It tends to be long.

  For this reason, the carrier clock CLOCK, the print data DATA, and the print data valid signal VALID transmitted from the main control unit 110 to the carriage 120 via the flexible flat cable are easily affected by noise. Of the above-described carrier clock CLOCK, print data DATA, and print data valid signal VALID, even if the print data DATA is affected by noise, the print area on the recording medium by one print data DATA is For example, since one side is extremely small such as 35 μm, the amount of printing disturbance is extremely small, which is a level with no problem. However, if the carrier clock CLOCK and the print data valid signal VALID are affected by noise, the print data will be shifted. Therefore, the carrier clock CLOCK and the print data valid signal VALID are particularly sensitive to noise immediately after printing is started. If it is affected, the printing disturbance will spread over a wide range.

Here, as countermeasures against noise in the signal transmission of inkjet printers, the harness cables for transferring print data are arranged so that the harnesses do not affect each other, the harness cables are shielded, and the odd channels of the print head And a method of controlling the even signal channel by shifting the timing (see, for example, Patent Document 1).
JP 2002-29115 A

  However, in the method described in Patent Document 1 described above, although it is one of the noise suppression means for signal transmission, the harness cable cannot be mechanically arranged as described above, or the print head It cannot be applied when the timing cannot be divided for control purposes.

  FIG. 11 is a diagram illustrating an example of the case where the carrier clock CLOCK is missing due to the influence of noise in the printer 101 illustrated in FIGS. 8 and 9. FIG. 11A is a diagram illustrating the flow of print data, and FIG. FIG. 4 is a diagram illustrating a printing state on a recording medium in the printer head.

  In the printer 101 shown in FIGS. 8 and 9, as described above, the print data DATA is recognized by the print data valid signal VALID, and only the print data DATA among the continuous data transmitted from the main control unit 110 is conveyed. Since the writing is performed in the FIFO 160 in accordance with the clock CLOCK, as shown in FIG. 11A, when the carrier clock CLOCK is missing due to the influence of noise, the 23rd print data DATA carried by the missing carrier clock CLOCK is the FIFO 160. Will not be written to. Further, the print data valid signal VALID transmitted from the main control unit 110 is “1” only at the timing at which the print data DATA is incorporated in the continuous data transmitted from the main control unit 110. Even if a part of the print data is not written in the FIFO 160 due to the lack of the carrier clock CLOCK, it falls to “0” in accordance with the transmission timing of 10 continuous print data DATA. As a result, in this area, the print data DATA written in the FIFO 160 is 9 prints even though 10 print data DATA is continuous in a state where the data is transmitted from the main control unit 110 to the carriage 120. Only data DATA is continuous.

  Therefore, the print data DATA accumulated in the FIFO 160 is transmitted to the printer head 130 as continuous head data HD-DATA under the control of the head timing controller 170, and printing is performed on the recording medium according to the head data HD-DATA. As shown in FIG. 11 (b), printing is performed in a state where the 23rd print data DATA has been lost, and as a result, as shown by the hatched portion in FIG. All the print data DATA is shifted forward one by one.

  FIG. 12 is a diagram for explaining an actual image example when the print data is shifted forward one by one as shown in FIG. 11, and (a) is a diagram showing a state in which the print data is not missing. (B) is a diagram showing a state in which print data is missing.

  If a part of the print data DATA written in the FIFO 160 is lost due to the lack of the carrier clock CLOCK, as shown in FIG. 12, all the print data DATA after the missing print data DATA are shifted forward one by one. The deviation extends to the end of one scan of the print head 130, and the image formed on the recording medium is greatly disturbed.

  FIGS. 13A and 13B are diagrams illustrating an example in which the carrier clock CLOCK increases due to the influence of noise in the printer 101 illustrated in FIGS. 8 and 9. FIG. 13A is a diagram illustrating the flow of print data, and FIG. FIG. 4 is a diagram illustrating a printing state on a recording medium in the printer head.

  In the printer 101 shown in FIGS. 8 and 9, as described above, the print data DATA is recognized by the print data valid signal VALID, and only the print data DATA among the continuous data transmitted from the main control unit 110 is conveyed. Since writing is performed in the FIFO 160 according to the clock CLOCK, as shown in FIG. 13A, when the transport clock CLOCK increases due to the influence of noise, the 23rd print data DATA transported by the increased transport clock CLOCK is duplicated. Then, the data is written in the FIFO 160. Further, the print data valid signal VALID transmitted from the main control unit 110 is “1” only at the timing at which the print data DATA is incorporated in the continuous data transmitted from the main control unit 110. Even when a part of the print data is written to the FIFO 160 in an overlapping manner due to the increase in the carrier clock CLOCK, the print clock falls to “0” in accordance with the transmission timing of the 10 continuous print data DATA. As a result, in this area, the print data DATA written in the FIFO 160 is 11 prints even though 10 print data DATA is continuous in a state where the data is transmitted from the main control unit 110 to the carriage 120. Data DATA is continuous.

  Therefore, the print data DATA accumulated in the FIFO 160 is transmitted to the printer head 130 as continuous head data HD-DATA under the control of the head timing controller 170, and printing is performed on the recording medium according to the head data HD-DATA. As shown in FIG. 13B, printing is performed in a state where the 23rd print data DATA is overlapped. As a result, as shown by the hatched portion in FIG. All the print data DATA is shifted backward one by one.

  FIG. 14 is a diagram for explaining an actual image example when the print data is shifted backward one by one as shown in FIG. 13, and (a) shows a state where the print data is not duplicated. FIG. 4B is a diagram showing a state where print data is duplicated.

  When a part of the print data DATA written to the FIFO 160 is overlapped and written to the FIFO 160 due to the increase of the carrier clock CLOCK, as shown in FIG. 14, all the print data DATA after the overlapped print data DATA are moved backward by one. And the deviation reaches the end of one scan of the print head 130, and the image formed on the recording medium is greatly disturbed.

  The present invention has been made in view of the problems of the conventional techniques as described above, and has a wide range even when the conveyance clock transmitted from the main control unit to the carriage together with the print data is increased or decreased by noise. An object of the present invention is to provide a print data transfer method and a recording apparatus capable of avoiding a serious print disturbance and suppressing a significant deterioration in print image quality.

In order to achieve the above object, a print data transfer method of the present invention includes a print head that includes a plurality of nozzles for ejecting ink and prints continuous print data at a predetermined timing for each number of nozzles, and includes the print head. A carriage that moves; a print data control unit that is provided on the carriage and controls output of the print data to the print head; and a main control unit that is placed outside the carriage and transmits the print data to the print data control unit. The print data transmitted continuously from the main control means to the print data control unit and incorporated into the continuous data carried one data per clock in synchronism with the carry clock. A print data transfer method for transferring to a print head, wherein the predetermined number is equal to the number of nozzles, and the continuous data transmitted from the main control means. Wherein the print data valid signal VALID indicating the print data, said the continuous data including the print data, the transfer clock and the print data control unit from said main control means to be transferred to the print head of the data based and transmitting, to the print data valid signal vALID, the first number of carrier clock from the carrier clock which is synchronized with the beginning of the data of the print data identified in the period indicated by the print data valid signal vALID The continuous data is fetched in accordance with the carry clock in order from the head data while the carry clock number reaches the predetermined number, and the fetched predetermined number of the continuous data is the print data. Indicating that the fetched predetermined number of the continuous data is the print data. The print data valid signal WVALID is generated in synchronization with the period of the predetermined number of the continuous data fetched, and the generated print data valid signal WVALID is within one period indicating that the print data valid signal is the print data. And a step by the print data control unit that transfers the predetermined number of captured continuous data as the print data to the print head. The recording apparatus of the present invention includes a plurality of nozzles for ejecting ink, and prints continuous print data at a predetermined timing for each number of nozzles, a carriage mounted with the print head, and a carriage that moves. In the recording apparatus, comprising: a print data control unit that is provided and controls output of the print data to the print head; and a main control unit that is placed outside the carriage and transmits the print data to the print data control unit. Includes: a transport clock to the print data control means; continuous data including the print data that is transported one data per clock in synchronism with the transport clock and continuously incorporated for each number of nozzles; and the continuous data the transmit and print the data valid signal vALID indicating that said print data to be transferred to the print head, the of the The print data control unit, based on the print data valid signal VALID, the carrier clock from the carrier clock which is synchronized with the beginning of the data of the first to the print data identified in the period indicated by the print data valid signal VALID While the number of transport clocks reaches the number of nozzles, the continuous data is captured according to the transport clock sequentially from the top data, and the captured predetermined number of the continuous data is the print data. The print data valid signal WVALID is updated in synchronization with the fetch period of the predetermined number of the continuous data in order to indicate that the predetermined number of the continuous data fetched is the print data. , Indicating that the updated print data valid signal WVALID is the print data The continuous data of the predetermined number of captured said to be transferred to the print head as the print data within, and wherein.

  In the present invention configured as described above, when print data is continuously incorporated into the continuous data carried by the carry clock every predetermined number and transmitted to the carriage, the continuous print data is received at the carriage. From the time the head data is received by the carriage to the time when a predetermined number of transport clocks with continuous print data are measured, continuous data is captured according to the transport clock, and this continuous data is printed as print data. Transferred to the head.

  As a result, even when the carrier clock is increased or decreased due to noise, a predetermined number of continuous data in which print data continues is transferred to the print head as print data, and the subsequent print data is shifted back and forth. Nothing will happen.

  As described above, in the present invention, after the head data of continuous print data is received by the carriage, a predetermined number of continuous data in which the print data is continuous is taken and transferred as print data to the print head. Therefore, even when the carrier clock is increased or decreased due to noise, the influence of the increase or decrease in the carrier clock is converged within one continuous print data, thereby causing a wide range of print disturbances. This can be avoided, and significant deterioration of the print image quality can be suppressed.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing an embodiment of the recording apparatus of the present invention, and FIG. 2 is a block diagram showing the configuration of the print data control unit 22 shown in FIG.

  As shown in FIG. 1, the present embodiment is a printer 1 connected to a host apparatus 2 and discharges ink droplets to a recording medium and a main control unit 10 that is a main control means for controlling the entire printer 1. The print head 30 for forming an image, the carriage 20 on which the print head 30 is mounted and controlling the print head 30, the linear encoder 40 for detecting the position of the carriage 20, and the end of the recording medium are detected. An edge sensor 50 is provided, and the print head 30 is controlled by the main control unit 10 via the carriage 20.

  The carriage 20 is provided with a CPU bus interface 21, a print data control unit 22, an ejection signal generation unit 23, a D / A converter 24, and an A / D converter 25.

  The CPU bus interface 21 distributes and outputs carriage control information set by a CPU (not shown) of the main control unit 10 to the print data control unit 22, the discharge signal generation unit 23, and the D / A converter 24, Information from the A / D converter 25 is transmitted to the CPU of the main control unit 10.

  The ejection signal generation unit 23 outputs a trigger signal TRIG indicating the timing of transmitting the print data to the print head 30 according to the position of the carriage detected by the linear encoder 40, and the print data control unit 22. An ejection signal FIRE is output to the print head 30.

  The print data control unit 22 transmits the print data DATA transmitted from the main control unit 10 to the print head 30 as head data HD-DATA at a timing according to the trigger signal TRIG output from the ejection signal generation unit 23.

  The A / D converter 25 receives head temperature information THRM indicating the temperature of the print head 30 transmitted from the print head 30 and an edge signal EDGE indicating the position of the end of the recording medium detected by the edge sensor 50. Convert to digital signal. The information converted into the digital signal is transmitted to the CPU of the main control unit 10 via the CPU bus interface 21. The print head 30 is equipped with a thermistor (not shown) for measuring the temperature of the print head 20, and head temperature information THRM is transmitted to the A / D converter 25 from this thermistor.

  The D / A converter 24 converts the head voltage information transmitted from the CPU of the main control unit 10 via the CPU bus interface 21 into an analog signal and transmits the analog signal to the print head 30. In the CPU of the main control unit 10, the control voltage of the print head 30 is set based on the head temperature information THRM transmitted from the A / D converter 25 via the CPU bus interface 21, and the control voltage is set as the head voltage. Information is transmitted to the D / A converter 24.

  As shown in FIG. 2, the print data control unit 22 includes a reception data controller 80, a FIFO 60 as storage means, and a head timing controller 70 as timing control means.

  The reception data controller 80 receives the data at the head of the print data DATA transmitted from the main control unit 10 in a state where the reception data controller 80 continues to the continuous data carried by the carrier clock CLOCK for every predetermined number of times, and then receives the carrier clock CLOCK. The counter 81 is a measuring means for measuring the print data, and continuous data is taken in as print data according to the carrier clock CLOCK, and the print data valid signal VALID transmitted together with the print data DATA from the main control unit 10 is received by the counter 81 by a predetermined number Is updated to indicate that the continuous data captured until the carrier clock CLOCK is measured is print data, and the captured print data WDATA and the updated print data valid signal WVALID are output. With data control means And a that FIFO write controller 82.

  The head timing controller 70 notifies the FIFO 60 of the print timing of the print head 30 by outputting the read enable signal RDEN to the FIFO 60 at a timing corresponding to the trigger signal TRIG output from the ejection signal generation unit 23. .

  The FIFO 60 temporarily accumulates the print data WDATA output from the reception data controller 80, and the accumulated print data WDATA at the print timing according to the read enable signal RDEN output from the head timing controller 70. To the printer head 30.

  Hereinafter, a print data transfer method in the carriage 20 of the printer 1 configured as described above will be described.

  FIGS. 3A and 3B are diagrams for explaining a print data transfer method in the carriage 20 shown in FIGS. 1 and 2, wherein FIG. 3A shows a data flow, and FIG. 3B shows a data flow. It is a figure which shows the process of the reception data controller 80 in A part.

  As shown in FIG. 3A, in the printer 1 shown in FIGS. 1 and 2, the print data DATA given to the main control unit 10 in accordance with a command from the host device 2 is carried by the carry clock CLOCK. 10 pieces corresponding to the number of nozzles of the print head 30 are continuously incorporated into the continuous data and transmitted to the carriage 20. Further, the main control unit 10 transmits a print data valid signal VALID indicating the print data DATA among the continuous data, together with the carrier clock CLOCK and the print data DATA. This print data valid signal VALID is synchronized with the carrier clock CLOCK and is “1” at the timing of the print data DATA among the continuous data transmitted from the main control unit 10 and “0” at other timings. Thus, the print data DATA is shown.

  The print data DATA and the print data valid signal VALID transmitted to the carriage 20 together with the carrier clock CLOCK in this way are received by the print data control unit 22 of the carriage 20.

  In the print data control unit 22, among the continuous data transmitted from the main control unit 10, the print data DATA incorporated and transmitted in the continuous data is recognized by the print data valid signal VALID. That is, the continuous data received at the timing when the print data valid signal VALID is “1” is recognized as the print data DATA.

  In the print data control unit 22, first, when the print data valid signal VALID rises to “1”, the top of the print data DATA in a continuous state among the continuous data transmitted from the main control unit 10 is thereby generated. The data is detected, and the counter 81 of the reception data controller 80 starts measuring the carrier clock CLOCK from that timing, and the FIFO write controller 82 takes in the received continuous data as print data according to the carrier clock CLOCK. The print data WDATA to be transmitted to the print head 30 is output. Note that the print data WDATA output from the FIFO write controller 82 is also output from the FIFO write controller 82 in a state of being incorporated into continuous data in the same manner as the print data DATA transmitted from the main control unit 10 to the carriage 20. The FIFO write controller 82 outputs the print data valid signal WVALID as the print data valid signal WVALID when the print data valid signal VALID is “1”.

  Thereafter, when the measured value in the counter 81 reaches 10, which is the number of nozzles of the print head 30, the FIFO write controller 82 sets the print data valid signal VALID to "0" and outputs it as the print data valid signal WVALID. The number of nozzles of the print head 30 is given in advance from the CPU of the main control unit 10 to the reception data controller 80 via the CPU bus interface 21. In the FIFO write controller 82, the measured value in the counter 81 is the main control. When the number of nozzles given from the CPU of the unit 10 is reached, the print data valid signal VALID is set to “0”.

  The print data WDATA output from the FIFO write controller 82 and the print data valid signal WVALID are input to the FIFO 60. Among the continuous data input in the FIFO 60, the print data WDATA indicated by the print data valid signal WVALID, that is, the print data. Only the print data WDATA whose valid signal WVALID is “1” is temporarily stored. Therefore, in the case shown in FIG. 3, the print data WDATA1 to 10, the print data WDATA11 to 20, the print data WDATA21 to 30, and the print data WDATA31 to 40 are continuously accumulated in the FIFO 60. .

  The print data WDATA accumulated in the FIFO 60 is transmitted to the printer head 30 as head data HD-DATA at a print timing based on the read enable signal RDEN output from the head timing controller 70. Here, in the FIFO 60, only the data set as the print data WDATA by the print data valid signal WVALID is stored among the continuous data input to the FIFO 60. Therefore, the head data transmitted from the carriage 20 to the print head 30 is stored. HD-DATA is transmitted to the printer head 30 in a state where the print data WDATA is continuous.

  In the print head 30, based on the head data HD-DATA transmitted from the carriage 20, ink droplets are ejected onto the recording medium at a timing according to the ejection signal FIRE output from the ejection signal generation unit 23 of the carriage 20. An image is formed on the recording medium.

  Hereinafter, the operation of the carriage 20 in the printer 1 shown in FIGS. 1 and 2 when the carry clock CLOCK increases or decreases due to the influence of noise will be described.

  First, the case where the carrier clock CLOCK is missing due to the influence of noise will be described.

  FIG. 4 is a diagram showing the operation of the carriage 20 in the printer 1 shown in FIGS. 1 and 2 when the carrier clock CLOCK is missing due to the influence of noise. FIG. 4A is a diagram showing the flow of print data. FIG. 7B is a diagram illustrating processing of the reception data controller 80 in the A part illustrated in FIG. FIG. 5 is a diagram showing a printing state on the recording medium in the state shown in FIG.

  The print data DATA and the print data valid signal VALID transmitted from the main control unit 10 to the carriage 20 together with the conveyance clock CLOCK are received by the print data control unit 22 of the carriage 20 and, as described above, the print data valid signal VALID. Thus, the head data of the print data DATA in a continuous state is detected from the continuous data transmitted from the main control unit 10, and the measurement of the carrier clock CLOCK is started in the counter 81 of the reception data controller 80 from that timing. At the same time, the FIFO write controller 82 takes the received continuous data as print data in accordance with the carrier clock CLOCK and outputs it as print data WDATA to be transmitted to the print head 30. At this time, as shown in FIG. 4, it is assumed that the transport clock for transporting the 23rd print data DATA is missing due to noise.

  In the FIFO write controller 82, the print data DATA is captured according to the carrier clock CLOCK, and therefore the 23rd print data DATA lacking the carrier clock CLOCK is not captured.

  The FIFO write controller 82 outputs the print data valid signal WVALID as the print data valid signal WVALID when the print data valid signal VALID is “1”.

  Thereafter, when the measured value in the counter 81 reaches 10, which is the number of nozzles of the print head 30, the FIFO write controller 82 sets the print data valid signal VALID to "0" and outputs it as the print data valid signal WVALID. Here, since the carrier clock CLOCK is missing by one print data DATA, the continuous data x following the 30th print data DATA is sent to the FIFO write controller 82 when the print data valid signal VALID is set to “0”. After it is taken in.

  The print data WDATA output from the FIFO write controller 82 and the print data valid signal WVALID are input to the FIFO 60. Among the continuous data input in the FIFO 60, the print data WDATA indicated by the print data valid signal WVALID, that is, the print data. Only the print data WDATA whose valid signal WVALID is “1” is temporarily stored. Here, since the print data valid signal WVALID output from the FIFO write controller 82 is “0” after the continuous data x following the 30th print data DATA is taken into the FIFO write controller 82, FIG. In the print data DATA in the area shown in (b), continuous data x following the 30th print data DATA is accumulated in the FIFO 60 following the 21st, 22nd, and 24-30th print data DATA. become.

  The print data WDATA stored in the FIFO 60 is transmitted to the printer head 30 as head data HD-DATA in which the print data WDATA is continuous at the print timing of the read enable signal RDEN output from the head timing controller 70, and the print head At 30, ink droplets are ejected onto the recording medium at a timing based on the ejection signal FIRE output from the ejection signal generation unit 23 of the carriage 20 based on the head data HD-DATA transmitted from the carriage 20. An image is formed on the medium.

  In this example, although the 23rd print data DATA transmitted from the main control unit 10 has been dropped due to the lack of the carrier clock, the 10 pieces of continuous print data including the dropped print data DATA have been dropped. Since the continuous data x transmitted from the main control unit 10 is included after the print data at the end of the print data DATA, as shown by the hatched portion in FIG. The data shift is converged within the 10 print data, and the subsequent print data is not affected.

  Next, a case where the carrier clock CLOCK increases due to the influence of noise will be described.

  6 is a diagram illustrating the operation of the carriage 20 in the printer 1 illustrated in FIGS. 1 and 2 when the conveyance clock CLOCK increases due to the influence of noise. FIG. 6A is a diagram illustrating the flow of print data. FIG. 7B is a diagram illustrating processing of the reception data controller 80 in the A part illustrated in FIG. FIG. 7 is a diagram showing a printing state on the recording medium in the state shown in FIG.

  The print data DATA and the print data valid signal VALID transmitted from the main control unit 10 to the carriage 20 together with the conveyance clock CLOCK are received by the print data control unit 22 of the carriage 20 and, as described above, the print data valid signal VALID. Thus, the head data of the print data DATA in a continuous state is detected from the continuous data transmitted from the main control unit 10, and the measurement of the carrier clock CLOCK is started in the counter 81 of the reception data controller 80 from that timing. At the same time, the FIFO write controller 82 takes the received continuous data as print data in accordance with the carrier clock CLOCK and outputs it as print data WDATA to be transmitted to the print head 30. At this time, as shown in FIG. 6, it is assumed that the carry clock for carrying the 23rd print data DATA increases due to noise.

  In the FIFO write controller 82, the print data DATA is captured according to the carrier clock CLOCK, so the 23rd print data DATA with the increased carrier clock CLOCK is captured redundantly.

  The FIFO write controller 82 outputs the print data valid signal WVALID as the print data valid signal WVALID when the print data valid signal VALID is “1”.

  Thereafter, when the measured value in the counter 81 reaches 10, which is the number of nozzles of the print head 30, the FIFO write controller 82 sets the print data valid signal VALID to "0" and outputs it as the print data valid signal WVALID. Here, since the carry clock CLOCK is increased by one print data DATA, the timing when the print data valid signal VALID is set to “0” is before the 30th print data DATA is taken into the FIFO write controller 82. .

  The print data WDATA output from the FIFO write controller 82 and the print data valid signal WVALID are input to the FIFO 60. Among the continuous data input in the FIFO 60, the print data WDATA indicated by the print data valid signal WVALID, that is, the print data. Only the print data WDATA whose valid signal WVALID is “1” is temporarily stored. Here, since the print data valid signal WVALID output from the FIFO write controller 82 is “0” before the 30th print data DATA is taken into the FIFO write controller 82, it is shown in FIG. In the print data DATA in this area, the 21st, 22nd, 23rd, 23rd, and 24th to 29th print data DATA are accumulated in the FIFO 60.

  The print data WDATA stored in the FIFO 60 is transmitted to the printer head 30 as head data HD-DATA in which the print data WDATA is continuous at the print timing of the read enable signal RDEN output from the head timing controller 70, and the print head At 30, ink droplets are ejected onto the recording medium at a timing based on the ejection signal FIRE output from the ejection signal generation unit 23 of the carriage 20 based on the head data HD-DATA transmitted from the carriage 20. An image is formed on the medium.

  In this example, although the 23rd print data DATA transmitted from the main control unit 10 is duplicated due to an increase in the carrier clock, the 10 pieces that are in a continuous state including the duplicated print data DATA are duplicated. Since the last print data of the print data DATA is not accumulated in the FIFO 60, the deviation of the print data due to the increase in the print data is converged within the 10 print data as shown by the hatched portion in FIG. The subsequent print data is not affected.

  In this embodiment, the case where one of the carrier clocks increases or decreases has been described as an example. However, the number of carrier clocks that increase or decrease is not limited to one, and the present invention can be applied.

  Further, the number of continuous print data DATA transmitted from the main control unit 10 is not limited to 10 as long as it is equal to the number of nozzles of the print head 30, and is not equal to the number of nozzles of the print head 30. Also good.

1 is a block diagram showing an embodiment of a recording apparatus of the present invention. FIG. 2 is a block diagram illustrating a configuration of a print data control unit illustrated in FIG. 1. FIGS. 3A and 3B are diagrams for explaining a print data transfer method in the carriage shown in FIGS. 1 and 2, in which FIG. 3A is a diagram illustrating a data flow, and FIG. 3B is received data in a section A illustrated in FIG. It is a figure which shows the process of a controller. FIGS. 3A and 3B are diagrams illustrating the operation of the carriage when the conveyance clock CLOCK is missing due to the noise in the printer illustrated in FIGS. 1 and 2. FIG. 3A is a diagram illustrating the flow of print data, and FIG. It is a figure which shows the process of the reception data controller in the A section shown in FIG. It is a figure which shows the printing state with respect to the recording medium in the state shown in FIG. FIGS. 3A and 3B are diagrams illustrating the operation of the carriage when the conveyance clock CLOCK increases due to the influence of noise in the printer illustrated in FIGS. 1 and 2, and FIG. It is a figure which shows the process of the reception data controller in the A section shown in FIG. It is a figure which shows the printing state with respect to the recording medium in the state shown in FIG. It is a block diagram which shows the example of 1 structure of the conventional recording device. FIG. 9 is a block diagram illustrating a configuration of a print data control unit illustrated in FIG. 8. FIGS. 10A and 10B are diagrams for explaining the operation of the printer shown in FIGS. 8 and 9, in which FIG. 10A is a diagram illustrating a flow of print data, and FIG. 10B is a diagram illustrating a print state on a recording medium in the printer head. FIGS. 9A and 9B are diagrams illustrating an example of a case where the carrier clock CLOCK is missing due to the influence of noise in the printer illustrated in FIGS. 8A and 9B, FIG. 9A is a diagram illustrating a flow of print data, and FIG. It is a figure which shows the printing state with respect to. FIG. 12 is a diagram for explaining an example of an actual image when print data is shifted forward by one as shown in FIG. 11, (a) is a diagram showing a state in which no print data is missing, and (b). FIG. 4 is a diagram showing a state in which print data is missing. FIG. 10 is a diagram illustrating an example of the case where the conveyance clock CLOCK increases due to the influence of noise in the printer illustrated in FIGS. 8 and 9, (a) is a diagram illustrating a flow of print data, and (b) is a recording medium in the printer head. It is a figure which shows the printing state with respect to. FIG. 14 is a diagram for explaining an actual image example when the print data is shifted backward one by one as shown in FIG. 13, and (a) is a diagram showing a state in which the print data is not duplicated; ) Is a diagram showing a state in which print data is duplicated.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Main control part 20 Carriage 21 CPU bus interface 22 Print data control part 23 Discharge signal generation part 24 D / A converter 25 A / D converter 30 Print head 40 Linear encoder 50 Edge sensor 60 FIFO
70 Head Timing Controller 80 Receive Data Controller 81 Counter 82 FIFO Write Controller

Claims (2)

A plurality of nozzles that eject ink, and a print head that prints continuous print data for each nozzle number at a predetermined timing; a carriage that carries the print head and moves; and a print head that is provided on the carriage and that prints on the print head A print data control unit that controls output of data and a main control unit that is placed outside the carriage and transmits print data to the print data control unit, and carries one data per clock in synchronization with the carry clock. A print data transfer method for transferring the print data which is continuously incorporated into the continuous data by a predetermined number and transmitted from the main control means to the print data control unit, to the print head,
The predetermined number is equal to the number of nozzles;
Print data valid signal VALID indicating the print data to be transferred to the print head among the continuous data transmitted from the main control means, the continuous data including the print data, and the transport clock. Transmitting from the main control means to the print data control unit;
On the basis of the print data valid signal VALID, it measures the number of the carrier clock from the carrier clock initially synchronized to the beginning of the data of the print data identified in the period indicated by the print data valid signal VALID, the transport While the number of clocks reaches the predetermined number, the continuous data is captured in order from the leading data according to the carrier clock, and the captured predetermined number of the continuous data is the print data. In order to indicate that a predetermined number of the continuous data is the print data, a print data valid signal WVALID is generated in synchronization with the fetch period of the predetermined number of the continuous data, and the generated print data valid signal WVALID said captured of the predetermined number within a period to indicate that said print data Printing data transfer method having the steps according to the print data control unit to be transferred to the print head a continuous data as the print data. A plurality of nozzles that eject ink, and a print head that prints continuous print data for each nozzle number at a predetermined timing; a carriage that carries the print head and moves; and a print head that is provided on the carriage and that prints on the print head In a recording apparatus comprising: a print data control unit that controls output of data; and a main control unit that is placed outside the carriage and transmits print data to the print data control unit.
The main control means includes a transport clock to the print data control means, and continuous data including the print data that is transported by one data per clock in synchronism with the transport clock and continuously incorporated for each number of nozzles. A print data valid signal VALID indicating the print data to be transferred to the print head in the continuous data, and
The print data control unit, based on the print data valid signal VALID, the carrier clock from the carrier clock which is synchronized with the beginning of the data of the first to the print data identified in the period indicated by the print data valid signal VALID While the number of transport clocks reaches the number of nozzles, the continuous data is captured according to the transport clock sequentially from the top data, and the captured predetermined number of the continuous data is the print data. The print data valid signal WVALID is updated in synchronization with the fetch period of the predetermined number of the continuous data in order to indicate that the predetermined number of the continuous data fetched is the print data. 1 period indicating that the updated print data valid signal WVALID is the print data Wherein the continuous data of the predetermined number of captured be transferred to the print head as the print data, the recording apparatus characterized.

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