JP2012196887A - Printer, method of controlling the same, and program - Google Patents

Abstract

Image data processing is speeded up and a delay in printing operation is avoided.
A printing apparatus connectable to a host computer includes a receiving unit, a storage unit, a printing unit, and a control unit. The receiving unit receives print data from the host computer. The storage unit stores print image data generated based on the print data. The printing unit executes printing on the print medium based on the print image data. When the command included in the print data instructs printing of the image data, the control unit transfers the image data received after the command from the host computer in the receiving unit to the printing unit without going through the storage unit. Then, the printing unit is caused to execute printing based on the image data.
[Selection] Figure 2

Description

  The present invention relates to a printing apparatus connectable to a host computer, a control method for the printing apparatus, and a program for controlling the printing apparatus.

  A printing apparatus that is installed in a store or the like and issues a receipt or the like under the control of a host computer is known (for example, see Patent Document 1).

JP 2009-157474 A

  Based on commands and print data received from the host computer, it is necessary to generate data for the print head to execute a print operation (this data is referred to as print image data in this specification). In the printing apparatus described above, when the print data received from the host computer includes a large amount of image data, the processing takes a relatively long time, so that the printing operation is delayed.

  The present invention has been made to solve at least a part of the above-described problems, and an object of the present invention is to speed up the processing of image data and thereby avoid a delay in a printing operation.

  In order to solve at least a part of the above-described problems, the present invention can take various modes listed below.

  A first aspect of the present invention provides a printing apparatus that can be connected to a host computer. A first aspect of the present invention includes a receiving unit that receives print data from the host computer, a storage unit that stores print image data generated based on the print data, and a print medium based on the print image data And when the command included in the print data instructs printing of image data, the storage unit receives the image data received after the command from the host computer in the receiving unit. And a control unit that transfers the image data to the printing unit without passing through and causes the printing unit to execute printing based on the image data.

  According to such a configuration, the image data transmitted from the host computer is supplied directly from the receiving unit to the printing unit without undergoing processing such as generation of print image data or storage in the storage unit, so that processing time is increased. Can be shortened. Therefore, it is possible to avoid a delay in the printing operation.

  Generally, a printing apparatus stores received image data in a register such as a volatile memory (RAM or the like) or a reception buffer, and then stores it in a print buffer such as a volatile memory. In the present invention, paying attention to the feature that image data can be easily replaced with a data format that can be printed by the printing unit, printing is performed by transferring the image data directly from the receiving unit such as a register or a reception buffer to the printing unit. Yes. Since the amount of image data is often large, the effect of omitting the transfer process between the buffers becomes remarkable, and the process can be greatly improved in efficiency.

  In the first aspect of the present invention, a direct memory access controller is further provided, and the control unit causes the direct memory access controller to transfer the image data from the receiving unit to the printing unit.

  With such a configuration, the processing load on the control unit is reduced. Therefore, the printing operation can be further speeded up.

  In the first aspect of the present invention, the control unit can enable or disable transfer by the direct memory access controller according to an argument included in the command.

  According to such a configuration, it is possible to switch which of the control unit and the direct memory access controller executes transfer of image data from the receiving unit to the printing unit according to an argument indicating the number or density of the image data. It becomes possible. When the number and density of image data are small, the influence of the time required for setting the direct memory access controller tends to be relatively larger than the transfer time. In such a case, since the process may be faster when the control is executed by the control unit, efficient print control according to the contents of the print data and the state of the printing apparatus is possible.

  In the first aspect of the present invention, when the command included in the print data is an instruction to print characters, the control unit is configured to print the print image based on a character code received from the host computer by the receiving unit. It is characterized by generating data.

  According to such a configuration, efficient printing processing can be executed by distinguishing between processing of character data with a relatively low processing load and processing of image data with a relatively high processing load.

According to a second aspect of the present invention, a receiving unit that receives print data from a host computer, a storage unit that stores print image data generated based on the print data, and a print medium based on the print image data A control method of a printing apparatus including a printing unit that executes printing is provided. According to a second aspect of the present invention, when the command included in the print data instructs printing of image data, the storage unit stores the image data received after the command from the host computer in the reception unit. The image data is transferred to the printing unit without going through the process, and the printing unit is caused to execute printing based on the image data.
According to such a configuration, an effect similar to that of the first aspect of the present invention can be obtained.

  The present invention can also be realized as a program that causes a control unit included in a printing apparatus to execute the method for controlling the printing apparatus according to the second aspect.

1 is a block diagram illustrating a system configuration of a printing apparatus according to a first embodiment of the present invention. 3 is a flowchart illustrating a control method of the printing apparatus in FIG. 1. It is a block diagram which shows the system configuration | structure of the printing apparatus which concerns on 2nd Embodiment of this invention. 4 is a flowchart illustrating a control method of the printing apparatus in FIG. 3. 4 is a flowchart illustrating another example of the control method of the printing apparatus in FIG. 3.

  A printing apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. An example of a printing apparatus is a thermal line printer used for a POS system or the like. The POS system is configured by connecting a POS terminal installed at a retail store or the like and performing sales settlement to a host computer that performs sales registration processing and settlement processing. The printing apparatus according to the present invention is provided in a POS terminal, and is used for printing / issuing a receipt at the time of sales settlement.

  FIG. 1 shows a printing apparatus 2 according to the first embodiment of the present invention. The printing apparatus 2 can be connected to the host computer 1 and includes a printing control unit 10 and a printing unit 13.

  The print control unit 10 includes a control unit 11 including a CPU (central control device) and various peripheral circuits. The control unit 11 comprehensively controls each unit of the printing apparatus 2 by executing various programs such as a control program stored in a non-volatile memory 16 (not shown) or a ROM (read only memory) (not shown).

  The printing unit 13 includes a medium transport mechanism (not shown), a print head, and a head drive circuit. Under the control of the control unit 11, the medium transport mechanism transports the leading end portion of the roll paper as the print medium accommodated in the printing apparatus 2 toward the print head along a predetermined transport path. The print head of this embodiment is a thermal line head in which a plurality of heat generating elements are arranged in a direction orthogonal to the conveyance direction of the print medium. Under the control of the control unit 11, a heating element (dot forming element) applies heat to the surface (recording surface) of the roll paper, whereby characters and images are printed (recorded) on the roll paper. The leading end of the roll paper that has passed through the print head is cut automatically or manually by a cutting mechanism (not shown) and handed to the customer as a receipt.

  The printing apparatus 2 of the present embodiment can print image information such as a store logo, coupon information, and barcode on a receipt in addition to character information such as a store name, the name of a product sold, quantity and amount, and a total amount. It is said that.

  As shown in FIG. 1, the print control unit 10 further includes a reception unit 12, a command analysis unit 15, a nonvolatile memory 16, and a print buffer 17. Various data can be transmitted and received between these components via the data bus 19.

  The receiving unit 12 is an interface that receives various commands and data transmitted from the host computer 1 in accordance with a predetermined standard under the control of the control unit 11, and includes a register, a buffer, and the like. The receiving unit 12 temporarily stores various commands and data received from the host computer 1 via wired or wireless communication. At least a part of the receiving unit 12 may be formed in a predetermined storage area in a RAM (Random Access Memory) (not shown) used by the control unit 11 for forming a work area, or a dedicated memory is provided. It is good.

  The command analysis unit 15 sequentially reads and analyzes various commands stored in the reception unit 12 under the control of the control unit 11. The commands transmitted from the host computer 1 include commands that specify the attributes and positions of characters and images to be printed, commands that specify functions and operations of the printing apparatus, and the like. The command analysis unit 15 identifies processing to be executed in the printing apparatus 2 by analyzing the contents of the command. The command analysis unit 15 is realized as a function of the control unit 11. You may provide the hardware or software for exclusive use which implement | achieves the said function.

  The nonvolatile memory 16 is composed of a ROM or the like, and stores and holds various data in a rewritable manner in a nonvolatile manner. The nonvolatile memory 16 of the present embodiment stores data (font data) that defines the shape of various characters printed on a receipt. The data stored and held in the nonvolatile memory 16 may be stored in advance, or the data transmitted from the host computer 1 may be stored via the receiving unit 12.

  The print buffer 17 is an area for storing (developing) print image data generated for driving the thermal line head, and functions as a storage unit of the present invention. The print image data is generated as pixel data by rasterizing characters used for printing. For example, a pixel in which a dot is formed (driving a heating element) is represented by 1, and a pixel in which no dot is formed (a heating element is not driven) is represented by 0. The head drive circuit outputs a drive signal to each of the heating elements based on the print image data developed in the print buffer 17 and outputs a drive signal to each of the heating elements while synchronizing with a signal that defines the conveyance timing of the print medium. Print characters on receipt.

  The operation and control method of the printing apparatus 2 according to the present embodiment having the above-described configuration will be described below with reference to FIG.

  In the present embodiment, when a printing operation is executed, first, a command indicating whether the printing target is a character string or an image is transmitted from the host computer 1 and stored in the receiving unit 12 (step S11). . The command is subjected to analysis by the command analysis unit 15, and it is recognized whether the print target is a character string or an image (step S12). Specifically, an argument indicating whether the print target is a character string or an image is included in the command, and the command analysis unit 15 determines the print target with reference to the argument. The configuration may be such that when a specific argument is included, it is determined that the print target is an image, and when it is not included, the print target is determined as a character string.

  If it is determined that the print target is a character string (No in step S12), the control unit 11 waits for reception of a character code transmitted from the host computer 1 thereafter. When the character code is stored in the receiving unit 12, the control unit 11 reads out font data corresponding to the character code from the nonvolatile memory 16 and generates print image data corresponding to the character string (step S13). The generated print image data is developed in the print buffer 17 (step S14), and transferred to the printing unit 13 at a predetermined timing under the control of the control unit 11 (step S15). The printing unit 13 drives the thermal line head and the medium transport mechanism based on the print image data, and prints the designated character string on the receipt (step S16).

  The amount of print image data that can be processed at one time by the printing unit 13 corresponds to the number of heating elements provided in the thermal line head. When printing is executed based on the transferred print image data, the print medium is transported by a predetermined amount and waits for the supply of the next print image data. That is, for each print medium transport operation, print image data is supplied from the print buffer 17 to the printing unit 13 in an amount corresponding to the number of dots that can be printed by the thermal line head.

  If it is determined that the print target is an image (Yes in step S12), the control unit 11 waits for reception of image data transmitted from the host computer 1 thereafter. This image data corresponds to the above-described print image data, that is, is provided as pixel data for directly controlling the driving / non-driving of each heating element of the thermal line head. When the reception unit 12 confirms the reception of the image data, the control unit 11 transfers the image data to the printing unit 13 via the data bus 19 directly, that is, without going through the print buffer 17 (step S17). The printing unit 13 drives the thermal line head and the medium transport mechanism based on the supplied image data under the control of the control unit 11, and prints a predetermined image on the receipt (step S18).

  As described above, the amount of image data that can be processed by the printing unit 13 at a time corresponds to the number of heating elements provided in the thermal line head. Therefore, it is necessary to transfer the image data from the receiving unit 12 to the printing unit 13 for each data amount corresponding to the number of dots that can be printed by the thermal line head for each printing medium conveyance operation. This amount of data is defined as an argument in a command transmitted in advance from the host computer 1, and the command analysis unit 15 notifies the control unit 11 with reference to the argument. The control unit 11 performs direct transfer for each data amount specified by the argument.

  According to the above configuration, the image data transmitted from the host computer 1 is directly transmitted without processing such as generation of print image data, storage in the print buffer 17, and transfer from the print buffer 17 to the printing unit 13. Since the data is supplied from the receiving unit 12 to the printing unit 13, the processing time can be significantly reduced.

  A printing apparatus 22 according to a second embodiment of the present invention is shown in FIG. Elements having the same, equivalent or similar functions and configurations as in the first embodiment are given the same reference numerals, and repeated descriptions are omitted. This embodiment is different from the first embodiment in that the print control unit 10 includes a DMAC (direct memory access controller) 18.

  The DMAC 18 is a processor provided inside or outside the control unit 11. When a predetermined instruction is received from the control unit 11, the buffer or memory is directly accessed, and data transfer between these elements is controlled via the data bus 19.

  The operation and control method of the printing apparatus 22 according to the present embodiment will be described with reference to FIG. The same processes as those in the control method according to the first embodiment shown in FIG. 2 are denoted by the same reference numerals, and repeated descriptions are omitted. That is, the processing for printing a character string is the same as that in the first embodiment.

  In this embodiment, when it is determined that the print target is an image (Yes in step S12), the control unit 11 validates the DMA control of the DMAC 18. The DMAC 18 then waits for reception of image data transmitted from the host computer 1.

  When the DMAC 18 directly accesses the receiving unit 12 (direct memory access) and confirms reception of the image data, the DMAC 18 DMA-transfers the image data directly to the printing unit 13 via the data bus 19, that is, without going through the print buffer 17. (Step S27). The printing unit 13 drives the thermal line head and the medium transport mechanism based on the supplied image data under the control of the control unit 11, and prints a predetermined image on the receipt (step S18).

  According to the above configuration, the image data transmitted from the host computer 1 is directly transmitted without processing such as generation of print image data, storage in the print buffer 17, and transfer from the print buffer 17 to the printing unit 13. Since the data is supplied from the receiving unit 12 to the printing unit 13, the processing time can be significantly reduced. Further, since the DMAC 18 supplies the image data to the printing unit 13 by DMA control, the processing load on the control unit 11 is reduced. Therefore, the printing operation can be further speeded up.

  As described above, it is necessary to transfer the image data from the receiving unit 12 to the printing unit 13 for each data amount corresponding to the number of dots that can be printed by the thermal line head for each printing medium transport operation. This amount of data is defined as an argument in a command transmitted in advance from the host computer 1, and the command analysis unit 15 notifies the control unit 11 with reference to the argument. The control unit 11 instructs the DMAC 18 to execute DMA transfer for each data amount designated by the argument.

  Note that an argument indicating validity / invalidity of DMA control may be included in a command transmitted in advance from the host computer 1, and the argument may be referred to by the command analysis unit 15. In this case, it is possible to switch which of the control unit 11 and the DMAC 18 executes transfer of image data from the receiving unit 12 to the printing unit 13 according to an argument indicating the number or density of image data. Therefore, it is possible to maintain a high-speed printing operation according to the situation. For example, when the number and density of image data are small, the influence of the time required for setting the DMAC 18 tends to be relatively larger than the transfer time. In such a case, since the process may be faster when the control is executed by the control unit, efficient print control according to the contents of the print data and the state of the printing apparatus is possible.

  A control method of the printing apparatus 22 in this example will be described with reference to FIG. The same processes as those in the control method according to the second embodiment shown in FIG. 4 are given the same reference numerals, and repeated descriptions are omitted.

  In this example, when it is determined that the print target is an image (Yes in step S12), an argument indicating the validity / invalidity of DMA control included in the command transmitted from the host computer 1 is the command analysis unit 15. To determine whether or not the DMA control is instructed (step S30).

  If it is determined that DMA control activation is instructed (Yes in step S30), the control unit 11 validates the DMA control of the DMAC 18. As in the second embodiment, the DMAC 18 DMA-transfers the image data received by the receiving unit 12 to the printing unit 13 (step S27).

  If it is determined that the DMA control invalidation is instructed (No in step S30), the control unit 11 transfers the image data received by the receiving unit 12 to the printing unit 13 as in the first embodiment. (Step S17). If bus division control or the like is used, the DMAC 18 can cope with another task during the transfer processing by the control unit 11, and more efficient control processing is possible.

  In each of the above embodiments, at least a part of the control executed by the print control unit 10 may be realized by software included in the DMAC 18 or a printer driver installed in the host computer 1.

  The control method of the printing apparatus according to the present invention is also applicable to a page printer that uses a cut sheet as a print medium. When it is necessary to print an image on the header or footer of each page of the document, it is possible to reduce the processing load and avoid the delay of the printing operation.

  In the printing apparatus control method according to the present invention, a thermal head including a plurality of heating elements arranged in a print medium conveyance direction is mounted on a carriage, and the carriage is scanned in a direction perpendicular to the print medium conveyance direction. It is also applicable to serial printers that perform printing. Even in this case, the amount of image data that can be processed by the printing unit 13 at a time corresponds to the number of heating elements included in the thermal head. When printing is executed based on the transferred image data, the carriage is scanned by a predetermined amount and waits for the supply of the next image data. That is, image data is supplied from the print buffer 17 to the printing unit 13 by a data amount corresponding to the number of dots that can be printed by the thermal head for each unit scan of the carriage. This amount of data may be defined by an argument included in a command transmitted in advance from the host computer 1.

  The driving method of the printing apparatus according to the present invention can also be applied to a printer including an ink jet type or dot impact type print head. Each pixel data constituting the image data or the print image data defines ejection / non-ejection of ink droplets in an ink jet type printer, and defines driving / non-driving of a needle in a dot impact type printer. It becomes. Any of these methods can be applied to both a line-type head and a serial-type head based on the above-described data configuration.

  The above-described embodiments of the present invention are intended to facilitate understanding of the present invention, and do not limit the present invention. The present invention can be changed and improved without departing from the spirit and scope of the claims, and equivalents thereof are included in the present invention.

  1: host computer, 2: printing device, 11: control unit, 12: reception unit, 13: printing unit, 15: command analysis unit (control unit), 17: print buffer (storage unit), 18: DMAC

Claims (6)

A printing device connectable to a host computer,
A receiving unit for receiving print data from the host computer;
A storage unit for storing print image data generated based on the print data;
A printing unit that executes printing on a print medium based on the print image data;
When the command included in the print data is an instruction to print image data, the image data received after the command from the host computer in the receiving unit is sent to the printing unit without going through the storage unit. A control unit for transferring and causing the printing unit to execute printing based on the image data;
A printing apparatus comprising: Further equipped with a direct memory access controller,
The printing apparatus according to claim 1, wherein the control unit causes the direct memory access controller to transfer the image data from the receiving unit to the printing unit.   The printing apparatus according to claim 2, wherein the control unit can enable or disable transfer by the direct memory access controller according to an argument included in the command.   When the command included in the print data is an instruction to print characters, the control unit generates the print image data based on the character code received from the host computer in the receiving unit. The printing apparatus according to any one of claims 1 to 3. A receiving unit that receives print data from a host computer, a storage unit that stores print image data generated based on the print data, and a printing unit that executes printing on a print medium based on the print image data A method for controlling a printing apparatus,
When the command included in the print data is an instruction to print image data, the image data received after the command from the host computer in the receiving unit is sent to the printing unit without going through the storage unit. Forward,
Causing the printing unit to execute printing based on the image data;
A control method for a printing apparatus.   A program for causing a control unit included in a printing apparatus to execute the method for controlling the printing apparatus according to claim 5.

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