JPH0618034B2 - Clipping control method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a clipping control system suitable for use in a printer having a line buffer.

[Technical background of the invention and its problems]

Recently, the demand for graphic and image processing has increased, and printers that can handle not only characters but also graphics have emerged. Up to now, it has been a rule that the print information supplied to the printer device does not exceed the size of the paper surface. For this reason, the printer hardware requires software to send print information that does not exceed the paper size, and therefore obliges the software creator to perform abnormal processing when an error transfer occurs.

On the other hand, for example, one paper may be divided into two, and a request may be made to print a document on one side and a graphic on the other side. What is needed to meet the above specifications is:
This is a means for preventing the invasion of the area such that the areas do not interfere with each other, like the case where the divided areas are regarded as the paper size.

In recent years, graphic processing has been regarded as important and easy to handle, and as mentioned above, it is not troublesome to request print information that does not exceed the area and handle incorrectly sent ones as abnormal. Instead, flexible response is desired.
Particularly, in the case of a serial printer such as a laser beam printer which has a capacity of one line except a buffer having a paper size buffer, there is a process other than the process for preventing the area interference as described above when the graphic information is developed. In addition, it is necessary to compare the current head position with the graphic information. Therefore, the processing is complicated and, as a result, the processing speed is adversely affected.

[Object of the Invention]

The present invention has been made in view of the above-mentioned drawbacks.
It is an object of the present invention to provide a clipping control method for a printer having only a buffer capacity for lines, which provides an efficient means for preventing an interference action of an area and speeds up the processing at the time of image development. .

[Outline of Invention]

INDUSTRIAL APPLICABILITY The present invention is used not in a device having a page buffer such as a laser beam printer but in a device having only a buffer size for one line such as a serial printer. Is the only one and absorbs in this region in the pretreatment stage. To achieve this,
A clipping area setting means is provided which includes a clipping register and a buffer clipping register, and which sets an area for clipping in the clipping register in accordance with a setting value of software, and a print head area currently located and a value set in the clipping register. And a preprocessing means for setting the optimum value according to the result in the buffer clipping register, and specifying the coordinate value to be written when the image is expanded in the line buffer and the buffer clipping register. The size is compared with the size of only one comparison target area, and the desired image data is written in the line buffer according to the result.

As a result, it is possible to prevent the area interference when the graphic information is developed into an image, expect efficient processing, and speed up the processing during image development.

Example of Invention

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of a system for implementing the present invention.
In the figure, 1 is a host CPU which is the center of the system. Reference numerals 2 and 3 are micro CPUs for controlling the keyboard unit 11 and the printer unit 12 which are installed for the purpose of reducing the load on the host CPU 1 and are externally connected. Each of these micro CPUs 2 and 3 is a keyboard unit 11
And built in the printer unit 12. An interface unit (IF) 4 controls a fixed disk unit 13 (HDD) and a floppy disk drive 14 (FDD) connected in a daisy chain. Reference numeral 5 is a CRT controller (CRTC) for controlling the CRT display unit 15, and 6 is a video RAM (V-RAM) for storing the display image. The above units 2, 3, 4, 5 and 6 are system buses 1
6 are commonly connected.

Reference numeral 7 is a ROM that stores the basic operation of the system, which is read and executed by the host CPU 1. A main memory (MM) 8 stores firmware and various information.
Clipping registers and buffer clipping registers added according to the present invention are allocated to the main memory 8 as register areas. Further, the firmware shown as a flowchart in FIG.
The image data is stored in the main memory 8 and is read and controlled by the host CPU 1 to expand the image data in the main memory 8. The image data developed here is the host CPU 1 and micro C
It is transmitted to a line buffer (not shown) built in the printer unit 12 under the control of the PU 3. Reference numerals 9 and 10 are memories (KPM) for storing Kanji patterns, and 9 for CRT and 10 for printer are prepared. 11 to 15 are various input / output devices, each of which is a keyboard unit 11 for inputting a message, a printer unit for printing messages and images, an external memory (HDD13, FDD14) for storing firmware and user information, and displaying messages and images. Each of the CRT displays 15 is shown.

FIG. 2 is a diagrammatic representation of the operation concept of the present invention, in which the area concept of the paper surface (), the software designated area (), and the line buffer area () are shown.

In the figure, Q ₀ and P ₀ are the minimum x and y coordinates of the paper surface area, Q ₁ and P ₁ are the maximum x and y coordinates, and x ₀ and y ₀ are the minimum x and y coordinates of the clipping area and x ₁ and y _1. Is the maximum x / y coordinate, r ₀ , s ₀ is the minimum x / y coordinate of the buffer clipping area, r ₁ , s ₁ is the maximum x / y coordinate, a
B indicates the minimum and maximum y coordinates of the print head area, and m ₀ and n ₀ indicate the minimum x and y coordinates of the figure.

FIG. 3 is a routine for initializing the clipping area setting register to the paper size when the system bulb is turned on, FIG. 4 is a routine for resetting the clipping register according to the value specified by software, and FIG. 5 is the print head area currently located. 7 is a firmware flow chart showing a routine for comparing the (vertical dot number) and the value indicated by the clipping register with each other and setting the resulting value as an optimum value in the buffer clipping register.

FIG. 6 shows a routine for comparing the position of an image to be written (hereinafter referred to as coordinate value) with the size of the buffer clipping register when the image is developed in the line buffer and writing the image data in the line buffer. It is a firmware flowchart.

The operation of the embodiment of the present invention will be described in detail below.

First, the operation concept of the present invention will be briefly described with reference to FIG.
From the figure information (straight line in this case), there are three areas. One is a paper surface area (), and the maximum print area corresponds to this. One more is clipping area ()
This is the actual print area that can be set as desired by software. The other one is a buffer clipping area (), and the graphic information contained in this area is to be developed as an image. (The buffer clipping area moves in the actual printing direction in the clipping area due to the movement of the print head.) That is, the drawing area is absorbed by the clipping area, and the clipping area is absorbed by the buffer clipping area. Only the buffer clipping area needs to be considered.

The flowcharts shown in FIGS. 3 to 6 are the processes for realizing the above. The operation of the embodiment of the present invention will be described in detail below. FIG. 3 shows processing that is always executed when the system is started up. By executing this processing, the paper surface area is absorbed by the clipping area. That is, the clipping area is set to the paper surface area by starting up the system.
The clipping area can be freely set within the paper area. As described above, when printing is performed by dividing one sheet into n (in the present embodiment, an example in which one sheet is divided into 1 is shown), the software (host CPU 1) designates the divided area. FIG. 4 shows the processing at this time, and it can be seen that the paper surface area absorbed at system startup is changed to the divided area designated by the software.

By executing one of the above-mentioned two processes, the second
As shown in the figure, the real-marking area to be processed thereafter is set.

The graphic information is sent with x-coordinates in the horizontal direction of the paper and y-coordinates in the vertical direction and parameterized coordinate values. The process shown in the flowcharts of FIGS. 5 and 6 determines whether or not the image development is performed by comparing with the current print head position based on the graphic information.

FIG. 5 shows the minimum / maximum x / y of the buffer clipping area.
It shows how the coordinate values are set. When the graphic information is image-developed, it must be determined whether the x and y coordinates are located within the clipping area and are included within the area of the current head position. A buffer clipping area is obtained by absorbing both areas as one area. Since the x coordinate is not affected by the head position, the x coordinate value set as the clipping area is set as it is. (X ₀ → r ₀ x ₁ → r ₁ ) On the other hand, the current head position greatly affects the y coordinate.
That is, since the coordinates of the line buffer where the image is to be developed are equal to the coordinates of the current head position, the size relationship with the set clipping area is an important factor in determining whether or not the image is developed. When the print area a of the head currently positioned is smaller than the clipping area y ₀ , y ₀ becomes the set value of the buffer clipping area s ₀ , otherwise a is
It becomes the set value of s ₀ . On the contrary, when the print area b of the head is smaller than the clipping area y ₁ , b becomes the set value of the buffer clipping area s ₁ , and otherwise, y ₁ is
It becomes the set value of s ₁ .

The buffer clipping area created based on such a judgment is used for comparison with the x and y coordinates of the graphic, and the graphic image is developed only for the portion located in the area. This is shown in the flow chart of FIG. Image writing to line buffer is 6th
It is performed in the process of the figure. In the processing shown in FIG. 6, it is checked whether the graphic x and y coordinates are in the buffer clipping area and then the image is written in the line buffer. As is clear from this process, it is only the buffer clipping region that is compared with the figure coordinates. In other words, by performing the preprocessing that absorbs the paper area into the clipping area and the clipping area into the buffer clipping area, only one area comparison target in the image writing processing can be performed, and the processing speed can be simplified. Can be measured.

〔The invention's effect〕

As described above, according to the present invention, the effects listed below can be obtained.

(1) It is possible to prevent the area interference when developing the graphic information image, and expect efficient processing.

(2) The processing speed can be increased by making the comparison target area unique when expanding the graphic information image.

(3) No matter how many areas there are, it only needs to be absorbed in the one area in the pre-processing stage, so there is no effect on the processing speed during image development.

[Brief description of drawings]

FIG. 1 is a block diagram of a system in which the present invention is implemented, FIG. 2 is a diagram schematically showing the operation concept of the present invention, and FIG.
6 to 6 are flowcharts of firmware used in the present invention. 1 ... Host CPU, 2, 3 ... Micro CPU, 4 ... Interface part (IF), 5 ... CRT display, 6 ... Video RAM (V-RAM), 7 ... ROM, 8 ... Main memory (M
M), 9, 10 ... Kanji pattern memory (KPM), 11 ...
Keyboard unit (KB), 12 ... Printer unit (P
RT), 13, 14 ... External memory (HDD / FDD), 15 ... CR
T display, 16 ... System bus.

Claims (1)

[Claims] 1. A printer device, which is connected to a host CPU via a bus and has a line buffer, has a processor unit and is equipped with a clipping register and a buffer clipping register, respectively. The clipping area setting means for setting an area for clipping is compared with the size relationship between the print head area at the present position and the value set in the clipping register, and the optimum value according to the result is compared with the buffer clipping. A pre-processing unit for setting in a register, comparing the coordinate value to be written when the image is developed in the line buffer with only one comparison target area designated by the buffer clipping register, According to the result Clipping control method, wherein a writing image data.