JPH05309882A - Page printer - Google Patents

Abstract

PURPOSE:To realize monochromatic or multicolor graphical processing without having one-page bit-map memory in a page printer, in which image data is expanded and pictured through bit-map memory. CONSTITUTION:A virtual bit-map memory for storing one-page image data is provided on a hard disc 6 and divided into a plurality of (such as six) blocks having the predetermined capacity. A bit-map memory 7 has only blocks, the number of which is fewer than that of the block just mentioned above or, for example, three. In accordance with a pointer provided on a RAM 4, image data are transferred between the blocks of the bit-map memory 7 and those of the virtual bit-map memory 61. When one-page image data completes on the virtual bit-map memory 61, picturing is performed through the bit-map memory 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a page printer for drawing graphics.

[0002]

2. Description of the Related Art A conventional page printer is equipped with at least one page of bit map memory in order to carry out a graphic drawing, in particular, one page of full graphic in which a filling process is performed. In particular, a color page printer featuring color graphics requires a huge bit map memory for n + 1 pages, where n is the number of primary colors required to represent the color.

[0003]

In the conventional page printer described above, when the graphic processing is to be realized, the bit map memory for at least one page,
Especially when trying to realize graphic processing in a color page printer, it is indispensable to install a bit map memory for n + 1 pages for the number of primary colors n, and a large-scale memory is installed in the printer control unit. It has the drawback of increasing the cost of the printer.

[0004]

A page printer according to the present invention is a means for analyzing and executing a print command and data from a higher-level device and developing it as image data in a bit map memory, and an image developed in this bit map memory. A page printer that draws data graphically in page units and has a virtual bit map memory that stores image data for one page divided into a plurality of blocks of a predetermined capacity; Of the bitmap memory having the same number of blocks as the capacity of the block of the map memory as the number of blocks of the virtual bitmap memory, and the block of the virtual bitmap memory and the block of the bitmap memory; Image data that controls the transfer of image data between And a feed control means.

Further, in the above configuration, the virtual bitmap memory may be provided for each different color to perform color printing.

[0006]

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

FIG. 1 is a block diagram of an embodiment of the present invention. The memory capacity of the bitmap memory 7 made of semiconductor memory that can be read and written at high speed is smaller than the capacity for storing bitmap data for the entire page, and the virtual bitmap for the entire page is stored in the hard disk 6 that has a slow read / write process. A memory 61 is provided (see the description of FIGS. 2 and 3 below). Main CPU2 is program R
Operates according to the program stored in OM3, RA
Data processing is performed using M4 and the data ROM 11 (font data storage). First, the print command from the host computer received by the host interface unit 1 is R
Store in AM4 area. Subsequently, the stored print command is read by the CPU 2 and analyzed. When drawing is performed in the bitmap memory as a result of the analysis execution, the CPU 2 searches which portion the bitmap memory 7 corresponds to the entire bitmap memory of one page. As a result of the search, if the address of the bitmap memory to be currently drawn and the address of the relevant bitmap memory 7 point to the same place, they are directly written in the bitmap memory 7. On the other hand, if the area pointed to by the bitmap memory 7 is out of the area to be written by the CPU 2, the data in the bitmap memory 7 is first written to the hard disk 6 through the hard disk controller 5. After saving the current data of the bitmap memory 7 in the hard disk 6, the data of the area of the bitmap memory to be written is read from the hard disk 6 to the bitmap memory 7 through the hard disk controller 5.
After that, the CPU 2 writes the data to be written in the bitmap memory 7.

All print commands from the host computer are processed according to the above procedure. That is, when the drawing process to the bitmap memory occurs, it is searched where the current bitmap memory 7 virtually points to one page, and if the addresses do not match, the bit map memory 7 The data of the map memory 7 is written to the hard disk 6, the data of the corresponding area of the bit map memory is read from the hard disk 6 into the bit map memory 7 again, and then the drawing process is performed on the bit map area of the bit map memory 7. This process is repeated until a print discharge command comes from the host computer.

When the print discharge command comes from the host computer, the data written in the bit map memory 7 at the end is written in the hard disk 6. Therefore, once the data in the bit map memory 7 is written in the corresponding area of the hard disk 6, 1 The image information of the page is completed on the virtual bitmap memory 61 on the hard disk 6.
Next, in the virtual bitmap memory that constitutes one page from the hard disk 6, the data for the area to be printed first is read into the bitmap memory 7 again.
When the CPU 2 finishes reading the print data into the bitmap memory 7, it issues a print command code to the bitmap memory control unit 8 and the engine control unit 9, and the bitmap memory control unit 8 outputs from the bitmap memory 7 While reading the data, the data is delivered to the engine control unit 9, and the printing unit 10 performs the printing process.

After the data reading by the bit map memory control unit 8 is started, the CPU 2 checks the address of the read memory and the bit map memory 7 has already been read by the bit map memory control unit 8. Data of the area to be printed next is read from the virtual bitmap memory 61 of one page completed on the hard disk 6 into the area, and is written in the bitmap area of the bitmap memory 7. At this time, the CPU 2 does not exceed the read address indicated by the bitmap memory control unit 8.
Is checked to prevent the data writing by the CPU 2 from overtaking the data reading by the bitmap memory control unit 8 and causing data destruction.

When the printing operation for all one page is completed by the above procedure, the CPU 2 waits for a normal paper discharge report from the engine control unit 9 and initializes the bitmap memory 7 and the bitmap data area on the hard disk 6. , End all processing of the current page.

2 and 3 are conceptual diagrams for explaining the relationship between the bit map memory 7 mounted on the control unit and the bit map memory 61 virtually formed on the hard disk 6 and the control method in this embodiment. .. Pointer table 41
Are placed on the RAM 4, the pointers are present in the same number according to the number m (m = 3 in FIGS. 2 and 3) in which the mounted bitmap memory 7 is divided, and each divided is on the hard disk 6. In the same manner, an address for indicating where in the similarly divided virtual bit map memory 61 it corresponds is entered.

In the initial state, as shown in FIG. 2, the pointer values are set so that the pointers are in a positive order from the top of the page of the virtual bitmap memory 61 on the hard disk 6, that is, the mounted bitmaps. The divided blocks I, II, and III of the memory 7 correspond to the divided blocks B1, B2, and B3 of the virtual bitmap memory 61 on the hard disk 6.

FIG. 3 shows the state of the pointer when the command from the host computer is analyzed and the lower part of the page is drawn. When a drawing request of an address corresponding to the divided block B4 of the virtual bitmap memory 61 on the hard disk 6 is issued, the pointer table 41
Is checked, and the block B farthest from the block B4
The pointer P1 pointing to 1 is selected. When the pointer P1 is selected, the data of the block I of the bit map memory 7 corresponding to the pointer P1 is the area currently pointed to by the pointer P1, that is, the hard disk 6 first.
It is written in the upper block B1. Then pointer P1
Is rewritten to indicate the block B4 on the hard disk 6, the data of the block B4 on the hard disk 6 is read into the block I of the bitmap memory 7,
After that, drawing to the address corresponding to the block B4 on the hard disk 6 is performed by writing to the block I of the bitmap memory 7. Then, when a drawing request of an address corresponding to the divided block B5 of the virtual bitmap memory 61 on the hard disk 6 is generated,
The pointer table 41 is checked, and the pointer P pointing to the block B1 farthest from the block B5
2 is selected. When the pointer P2 is selected, the data of the block II of the bitmap memory 7 corresponding to the pointer P2 is first written in the area currently pointed to by the pointer P2, that is, the block B2 on the hard disk 6.
Then, the value of the pointer P2 is rewritten to indicate the block B5 on the hard disk 6, the data of the block B5 on the hard disk 6 is read into the block II of the bitmap memory 7, and then the address corresponding to the block B5 on the hard disk 6 is read. Is written by writing in the block II of the bitmap memory 7.

As described above, the drawing request to the virtual bit map memory 61 formed on the hard disk 6 is made by passing through the bit map memory 7 mounted in the control unit.

In FIGS. 2 and 3, the bit map memory forming one page is divided into 6 on the hard disk and 3 on the bit map memory 7, but this is for simplicity of explanation. The number of divisions and the width of division are the access speed of the hard disk 6 and the memory 7.
The optimum value varies depending on factors such as the amount of paper and the size of the paper to be printed, and is not limited to this example.

Next, an example of color printing will be described. In this embodiment, the hardware configuration is the same as that of the first embodiment shown in FIG. 1, and therefore its explanation is omitted here.

FIG. 4 shows an example in which the relationship between the virtual bit map memory 62 on the hard disk 6 and the bit map memory 7 mounted on the controller is applied to the case of color printing of n + 1 primary colors. Normally, for the color printing of n primary colors, another color black is used, so that the virtual bitmap memory 62 formed on the hard disk 6 is provided for n + 1 pages for the number n of primary colors. For convenience of description, FIG. 4 illustrates the case where the number of primary colors is n = 3.
A virtual bitmap memory 62 for n + 1 = 4 pages is provided on the hard disk 6. The virtual bitmap memory 62 is divided into 6 blocks for each page (color), and four blocks I to IV corresponding to 4 blocks are provided in the bitmap memory 7.
RAM with four pointers P1 to P4 designating blocks
4 pointer tables 42 can be set.

The drawing process is the same as that described in the first embodiment with reference to FIGS.

After the drawing processing for the three primary colors is completed, when the correction processing stage is entered, the CPU 2 causes the pointer table 42
Hard disk 6 by rewriting the pointer value of
Top page blocks B1, B7, B13 corresponding to the above colors
Data is read into the blocks I, II, and III of the bitmap memory 7, respectively. Subsequently, the three primary colors are calculated, and the result is written in the block IV as a correction value. When all the correction operations are completed, the result is written from the block IV of the bitmap memory 7 to the block B19 of the virtual bitmap memory 62 on the hard disk 6 indicated by the pointer P4 of the pointer table 42. When the writing is completed, the CPU 2 rewrites the pointers P1 to P4 of the pointer table 42 so as to indicate the next blocks B2, B8, B14, and B20 on the hard disk 6, and performs the same reading, correction calculation, and writing processing as described above. 1
After the correction process for all the pages is completed, the CPU 2 performs the print process as shown in the first embodiment, confirms the print discharge of the page, and then prepares the virtual bitmap memory 62, The pointer table 42 and the bitmap memory 7 are initialized.

In the present embodiment, FIG. 4 shows the bit map memory constituting one page on the hard disk as six.
It is divided into 3 + 1 colors, and it is shown in 3 divisions on the bit map memory, and one block for the correction color is added, but this is for simplicity of explanation. The optimum value differs depending on factors such as the amount of memory and the size of the printing paper, and is not limited to this example.

[0022]

As described above, the present invention has an effect that the amount of the bitmap memory mounted in the control unit can be reduced by mounting the hard disk and forming the virtual bitmap memory on the hard disk. Further, there is an effect that it is possible to easily perform graphic processing, which is difficult to realize in the past without mounting a memory for at least one page, in particular, filling processing of an indefinite area. further,
By providing all of the color printing processing that could not be realized without installing a huge amount of memory as a virtual bitmap memory on the hard disk, there is an effect that it can be realized with the same amount of memory as in the case of a single color. .. Therefore, the on-board memory of the page printer that performs graphic processing is significantly reduced, and the cost performance is significantly improved.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a conceptual configuration diagram showing an example of correspondence between a bitmap memory according to the present invention and a virtual bitmap memory on a hard disk.

FIG. 3 is a conceptual configuration diagram showing a modification example of the correspondence between the bitmap memory and the virtual bitmap memory in FIG.

FIG. 4 is a conceptual configuration diagram showing an example of correspondence between a bitmap memory and a virtual bitmap memory at the time of color printing.

[Explanation of symbols]

 1 Host Interface Section 2 CPU 3 Program ROM 4 RAM 5 Hard Disk Control Section 6 Hard Disk 7 Bitmap Memory 8 Bitmap Memory Control Section 9 Engine Control Section 10 Printing Section 11 Data ROM 41, 42 Pointer Table 61, 62 Virtual Bitmap Memory

Claims (2)

[Claims] 1. A page having means for analyzing and executing print commands and data from a higher-level device and developing the image data in a bitmap memory as image data, and means for drawing the image data developed in the bitmap memory In a page printer that draws graphics in units, a hard disk having a virtual bitmap memory that is divided into a plurality of blocks of a predetermined capacity to store image data for one page, and a block having the same capacity as the block of the virtual bitmap memory Image data for controlling transfer of image data between the bitmap memory and the block of the virtual bitmap memory, and the bitmap memory having a number smaller than the number of blocks of the virtual bitmap memory. Transfer control means. Jiprinter. 2. The page printer according to claim 1, wherein the virtual bitmap memory is provided for each different color to perform color printing.