JPS6298389A - Image display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an image display device, and in particular, an image display device that can move any display area on a display screen to any position (hereinafter, this operation is referred to as a scroll operation). The present invention relates to an image display device equipped with functions.

[Conventional technology]

FIG. 9 shows an imaging device according to the prior art.

In the figure, ■ indicates an input circuit that controls input of image data G.

The image data G is input to the CPU 2 at the subsequent stage. Said C
PU2 performs data processing on the image data G and outputs the result as display data H;
address calculation means 2B that extracts address information from the image data G and outputs the result as address data A for determining the display position of the image on the display surface of the CRT 3;
It is equipped with. The calculation result of the CPU2 is WORKR
It is designed to be stored in AM4.

The display data H and address data A output by the CPU 2 are input to the VDP 5 at the subsequent stage. The VDP 5 includes a writing means 5A that performs an input processing function of temporarily storing the display data 1 in the VRAM 6, and a reading means 5A that performs a display function of reading out the display data H stored in the VRAM 6 and displaying it on the CRT 3. 5B. The above input processing function is
5 is the display data H based on the address data A.
The above display function refers to the function of calculating the address for writing the data into the VRAM 6 and writing the display data H to the VRAM 6 based on the calculation result.
5 reads out the display data H from the VRAM 6, converts the display data H into RGB color signals to enable multi-color display, and further creates a synchronization signal and synchronizes with the synchronization signal to display the above color signals. It refers to the #Ji function that outputs a signal to the CRT 3 and displays it. The image will be displayed on the CRT 3 by this display function.

By the way, overall, HoDps is: (1) Large capacity RAM can be accessed.

(2) Has a dynamic RAM refresh function.

(3) It has a circuit that outputs a video signal of the NTSC system or PAL system.

(4) Has a multicolor display function.

(5) Logical operation of image data 1 Has functions such as overlapping of image data.

Next, the operation of the conventional display device configured in this way will be explained.

First, let me explain about the image data input processing operation.
Image data G is input through the input circuit 1 and sent to the CPU 2.

The CPU 2 extracts the address information contained in the image data G and determines the display position on the display screen of the CRT 3. Thereafter, information regarding the display position is sent to the VDP 5 as address data A. on the other hand,
The CPU 2 processes the image data G and sends the result as display data H to the VDP 5. Next, the VDP 5 inputs the address data A and display data H, and calculates a write address to the VRAM 6 from the address data A. Finally, the VDP 5 stores the display data H in the VRAM 6 based on the above calculation result and completes the input processing operation.

Next, the display operation of the display data H stored in the VRAM 6 by the above operation is as follows.

First, the VDP 5 reads the display data H from the VRAM 6 and converts the display data H into RGB to perform multicolor display.
Processing is performed to convert each color signal into a color signal. Next V
The DP 5 creates a synchronization signal to display the display data H on the CRT 3, and finally synchronizes the color signal with the synchronization signal and outputs it to the CRT 3 for display.

Incidentally, in addition to the input processing operation and display operation described above, the image display device has a function of moving the display position of the image displayed on the display screen of the CRT 3 by an arbitrary amount in the vertical and horizontal directions.

This operation is called a scroll operation, and this operation will be explained below.

First, the image data G input from the input circuit 1 is sent to the CPU
2 and it turns out to be a scrolling operation,
The CPU 2 calculates the scroll direction and scroll amount, and sends the results to the VDP 5.

Next, the VDP 5 changes the position from which the display data H is read from the VRAM 6 based on the above results, or
By replacing the display data H in M6, the display position of the image data G is changed, thereby scrolling the screen.

As in the above operation example, the VDP5 displays the VR of display data H.
Most of the writing and reading processing to AM6, the display operation of display data to the CRT, and the scrolling processing are performed. Therefore, the CPU 2 only performs processing such as determining the content of input image data.

When the VDP5 is used as an image display device in this way, the processing content of the CPU2 required for image processing is simplified, and the CPU2
The amount of programs and processing time can be saved. This is one of the reasons why VDP5 is widely used in recent image display devices.

[Problem that the invention seeks to solve]

However, the image display device according to the prior art has the following problems.

Generally, the number of pixels that can be displayed on a CRT display screen is standardized.

For example, consider a case where, in the pixel count configuration of image data G, the number of displayable pixels is J as shown in FIG. 10, and the number of pixels of image data input to the image display device is ■.

However, in this case, as shown in the figure, the image data of area X is displayed, but the data of areas Y and Z are not displayed. Thus, if the screen is scrolled to the right, data in area Z will not be displayed, and if the screen is scrolled to the left, data in area Y will not be displayed.

By the way, in recent home personal computers and the like, in order to save the capacity of the VRAM 6, the VRAM 6 usually has only enough capacity to store the data of the displayable area X. . Therefore, there is a problem that the data in areas Y and Z are truncated. Also, V'DP5 is the above area Y
Even if it has a function of storing data of area Z and area Z, the following problems occur. For example, when scrolling as described above, these data are transferred to the conventional VDP4.
In particular, software for efficient display using video processors used in home personal computers has not yet been developed.

Therefore, the present invention has been made in view of the above-mentioned problems of the prior art, and it is an object of the present invention to provide an image display device that can effectively perform a scrolling operation by storing data that was conventionally discarded.

[Means for solving problems]

The present invention is provided with a second storage means for storing image data other than that corresponding to the display screen among the image data.

[Effect]

In the present invention, since data other than the image data corresponding to the display screen is stored in the second storage means, the image data is not truncated.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 8. Note that the same components as those in the prior art are given the same reference numerals, and the description thereof will be omitted.

However, the CPU 2 according to the present invention has a built-in VRAM write area determining means 11, and an address data ROM 12 is attached to the CPU 2.

The writing means 5A of the VDP 5 stores the image data G in the VRAM 6 based on the VRAM writing area determining means 11.

Reference numeral 13 indicates storage means provided within the VRAM 5.

FIG. 2 is a diagram illustrating the configuration of the storage means 13.

Further, FIG. 3 shows the positions of image data viewed on the display screen of the CRT 3, each divided into areas 14 to 22. In FIG. 3, area 14 is the area that is actually displayed, and the other areas are not displayed. FIG. 2 shows the positions in the VRAMG where the data of the areas 15 to 22 and the display area 14 are stored, respectively. The above storage means 1
Area 14 of No. 3 functions as a first storage means, and areas 15 to 22 function as second storage means. Also, the second
First vertical area 23 in the figure. The second vertical area 24 and the horizontal area 25 are areas for temporarily storing data when exchanging data within VRAMe. Note that the diagonally shaded multiplication/division area 26 is an area where information other than image data (for example, text information for displaying the number of pages on the screen, 2 hours, etc.) is entered.

Further, in the above configuration example, the VRAM 6 is divided into two pages as a whole. Furthermore, display area 14 and area 15
22 are arranged in the VRAM 6 as shown in FIG. 2 in order to simplify the scrolling operation.

In addition, in this embodiment, an example of the configuration of the storage means 13 for storing data other than the display area 14 when there is no free space in the VRAM in the horizontal direction is shown for explanation of the operation described below.

Next, the present invention will be explained in detail.

Note that there are two types of characteristic operations in this embodiment, the first of which is input processing of image data G to the VRAM 6 and reading of the image data G from the VRAM 6 and CR
The second one is the display operation displayed at T3, and the second one is the scrolling operation of the displayed image.

First, the input processing and display operation described above are performed as follows.

Image data G input by the input circuit 1 in FIG. 1 is sent to the CPU 2 and processed as shown in the flowchart shown in FIG. 4, and the results are input to the VDP 5. The VDP5 temporarily stores the data in the VRAM6 based on this result, and then sequentially reads it out to the CRT.
Data is displayed for 3. At this time, VRAM6
The data read out is converted to RGB signals and sent to the CRT.
3 is output. These series of display operations except for the processing operations of the CPU 2 are equivalent to the operations of a normal image display device.

In the embodiment of the present invention, the part that performs the characteristic operation is the CP.
This is the processing method in U2, which will be explained using FIG.

First, when the CPU 2 inputs the image data G from the input circuit 1, in step S1, address information included in the data is selected and sent to the address calculation means 2B.

Next, in step S2, the position on the display screen of the CRT 3 at which the data should be displayed is calculated as follows using the above address information, and the result is output to the VRAM write area determining means 11.

The above address calculation method uses the address data ROM 12 in this embodiment in order to simplify the calculation.
When address information is input as a memory address of the address data ROM 12, the address data ROM 12
Therefore, address data A is read out.

Next, in step S3, the VRAM write area determining means 11 determines an address for writing data into the VRAM 6, as shown in FIG. In this case, for example, certain data may be displayed in the display area 1 on the screen shown in FIG.
4, the address data A is set in the display area 14 in step s4, and the address is set in the display area 14 in FIG.

In addition, in the case of data different from the above data, if it is determined that the data is data in non-display areas 15 to 22 in FIG. 2, the addos data is set to the non-display area in step S5. , similarly to the above, the area 15~ in FIG.
Set the address to 22.

After setting the address through the above operations, the process advances to the next step S6. In step S6, first, the image data G is sent to the data processing means 2B. The data processing means 2B decodes the image data G, determines which character pattern it is if it is character information, and outputs character data.

If it is color graphics information, it determines what color to display and outputs color data.

Thereafter, in step S7, the address data and character data or color data are output to the VDP 5, and the process ends.

Next, the scrolling operation will be explained.

First, when scrolling in the horizontal direction, the following four operations are performed.

(1) Scroll the page 1 part of the figure 2 (2) Scroll the page 2 part of the figure (3) Move the data of page 1 of the figure to page 2 (4) Move the data of page 2 of the figure The operations (1) to (4) above will be explained using the flowchart shown in FIG. 6, taking FIG. 5 as an example. First, when scrolling to the left, it looks like this:

First, the horizontal display width of the display area 14 in FIG.
In the figure, consider the case where the width is b, which is made up of the width of the A area 27 and the area within the large frame 28. The maximum scroll amount at one time is the width of area A 27, and the width of area B 29. C area 30
．． E area 32. F area 33. It is assumed that the widths of the H area 35 and the horizontal area 25 are equal.

In the case of left scrolling, the data in area A 27 is as shown in FIG.
Since there is no free area for data in the horizontal direction in the VRAM 6, the data will be stored in page 2. Therefore, when scrolling to the left, the flowchart shown in FIG. 6(a) is followed.

First, in step S1, data in area A 27 in FIG. 5 is entered into horizontal area 25.

Next, in step S2, the area within the large frame 28 is scrolled to the left.

At this time, the data in area B 29 enters area A 27, and area C 30 becomes a free area.

Next, in step S3, the data in the E area 32 is
Enter area 30. After that, in step S4, the large frame 2
8 and the data in the horizontal area 25 are scrolled to the left. With this operation, the data in the F area 33 enters the E area 32, and the horizontal area 25 becomes an empty area.

This completes left scrolling.

Next, in the case of right scrolling, the flowchart shown in FIG. 6(b) is followed.

Same as above, but in this case display area 14 in FIG.
Let the width of be a.

First, in step S1, the data in area E 32 and the data within the large frame 28 in FIG. 5 are scrolled to the right. At this time, the data in the E area 32 enters the F area 33 and the data in the N area 35 enters the horizontal area 25.

Next, in step S2, the data in the D area 31 is
Enter area 32. Next, in step S3, the data within the large frame 28 is scrolled to the right.

At this time, the B area 29 becomes a free area, and the data in the C area 30 enters the D area 31.

Thereafter, in step S4, the data in the horizontal area 25 enters the B area 29. This completes right scrolling.

Next, the following two operations are performed for the vertical scroll operation.

(1) Scrolling the display area (2) Displaying data in the non-display area
This will be explained below using figures. In FIG. 8, the area within the large frame 36 is the display area 14 in FIG. 2, and its data width is f. The maximum scroll amount in the vertical direction is the width of area 37, and the width of area 37 and area 39. It is assumed that the widths of the N region 40 and the first vertical area 23 are equal. Next, upward scrolling will be explained based on FIG. 7(a).

Scrolling upward requires an operation to store the data at the top because there is no free space above. Therefore, first, in step Sl, the data of the area 37 shown in FIG. 8 is input into the first vertical area 23. Next, in step S2, except for the data in the area 37, all remaining data is scrolled upward (data width e). At this time,
The first vertical area 23 becomes an empty area.

This completes the upward scrolling.

The scrolling downward will be explained based on FIG. 7(b).

First, in step S1, the data excluding the data in the first vertical area 23 is scrolled downward by the data width g. At this time, the first vertical area 23 has an N area 40
Contains data.

Next, in step S2, the data of the first vertical area 23 is entered into the area 37. This completes the downward scrolling operation.

Thus, scrolling operations in all the vertical and horizontal directions are performed in the manner described above.

In the above embodiment, the storage means lO in FIG.
The memory area other than the display area 11 in FIG.
For example, it may be provided in WORK RAMa). According to this method, the memory capacity in VRAM5 is the display area
This is effective when there is only enough space to store data in the VRAM 5 and there is no other free space in the VRAM 5. In the above case, the VRAM write area determining means 9 uses VDP4 and WORK RAM.
3 Address data will be sent to both parties.

Further, in the above embodiment, an example of operation was described in which the free space in the VRAM 5 is not in the horizontal direction as shown in the lower diagram of FIG. 2, but only in the vertical direction. However, this may be, for example, only in the horizontal direction, and the same effect as in the above embodiment can be achieved.

〔Effect of the invention〕

As explained above, according to the present invention, since the second storage means for storing image data other than the image data corresponding to the display screen among the image data is provided, the data other than the image data corresponding to the display screen is stored in the second storage. Since the image data is stored in the means, the image data is not truncated and an effective scrolling operation can be performed.

[Brief explanation of drawings]

1 to 8 show embodiments of the present invention, FIG. 1 is an overall configuration diagram, FIG. 2 is an explanatory diagram illustrating the storage contents of the storage means, and FIG. 3 is an explanatory diagram illustrating display operation. , FIG. 4 is a flowchart, FIG. 5 is an explanatory diagram explaining the horizontal scrolling operation, FIGS. 6 and 7 are flowcharts, FIG. 8 is an explanatory diagram explaining the vertical scrolling operation, and FIG. 9 10 and 10 show the prior art, FIG. 9 is an overall configuration diagram, and FIG. 10 is an explanatory diagram illustrating the problems of the prior art. 5A...Writing means, 5B...Reading means, 14...
Area (first storage means), 15-22...second storage means, G...image data. Agent Masuo Oiwa (2 idiots) Figure 6 (A) (B) No. 77 (A) (.) Matoi V 1

Claims (1)

[Scope of Claims] An image display device comprising display means having a display screen for displaying image data, and equipped with a scrolling function for moving displayed content up, down, left, and right within the display screen, comprising: A first storage means for storing image data corresponding to the display screen among the image data; a second storage means storing image data other than the image data corresponding to the display screen among the image data; It includes a writing means for distributing and storing data in the first and second storage means, respectively, and a reading means for reading the image data stored in the first and second storage means and displaying it on the display screen during scrolling. An image display device.