JPH03225392A - text display device - 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 a text display device that displays text on a screen with a fixed resolution, and in particular, the present invention relates to a text display device that displays text on a screen with a fixed resolution, and in particular, displays text on the entire display screen with various character string data together with a cursor. The present invention relates to a text display device capable of displaying text.

[Prior art and problems to be solved by the invention] In recent years, the display resolution of liquid crystal display panels, plasma display panels, etc. has improved and prices have fallen, and portable types of personal computers have also been developed. There is.

By the way, a large number of software used for personal computers is in circulation, including software developed in the past. However, as display media technology advances, the resolution of display screens that correspond to previously developed software generally has to be newly developed. The display screen is lower than that of the corresponding software. Therefore, even in the case of text display, the display font size corresponding to previously developed software is smaller than that corresponding to newly developed software.
Even on a text screen that displays character strings with the same number of lines, multiple character sizes will exist. Therefore, when using a newly developed display panel to display text created with software that has a text display screen that is lower than the degree of modification of this display panel, the displayed area will be smaller than the screen size of the display panel. . Therefore, a non-display portion is created on the screen, resulting in the inconvenience that the entire screen cannot be used effectively. FIG. 8 is a diagram for explaining that a hidden portion is created.

Referring to the figure, using a newly developed display panel with a display resolution of 640 x 480 dots (vertical x horizontal),
When displaying one page of text (font size 8 x 8 dots, 80 x 25 lines) set to correspond to the previously developed 640 x 200 dot display panel, the display area becomes 5/12 of the total, less than half of the total. 7/12 will be hidden.

To resolve this inconvenience, the character generator must be provided with character shape data other than 8x8 dots, such as 8x8 dots.
It is conceivable to create a program that stores x19 dots and sets a character size of 8 x 19 dots.

However, the setting of the font size is done by a core package (hereinafter referred to as the application program) for displaying characters in accordance with the resolution of the display panel, and this application program is compatible with the resolution of the newly developed display panel. This is what I did.

Moreover, since it is designed to be versatile, it is generally impossible for users, such as personal computer manufacturers and word processor manufacturers, to rewrite it. Additionally, this program is of a confidential nature and will not be disclosed.

In addition, in text display, a cursor indicating the next character input position is displayed. The display position of the cursor is specified by the application program using, for example, the 5th character on the 10th line and the number of lines in which the cursor should be displayed within the character box (for example, the 8th line at the bottom of the character box).

However, it is also necessary to recover the application program when changing the display position of the cursor to, for example, the 19th line, which is the lowest line in the character box, due to the above-mentioned change in character size. However, since it is impossible to modify the application program, it is also impossible to change the cursor display position.

The present invention has been made in view of the above problems, and provides a text display device that can display text along with a cursor on the entire screen even with previously developed software without modifying the application program. The purpose is to

[Means for Solving the Problems] A text display device of the present invention for achieving the above object includes: a screen display means; a first font size setting means adapted to the display resolution of the screen display means; and a screen display. a plurality of second character size setting means for setting various character string data that does not correspond to the display resolution of the means to a character size that can be displayed on the entire screen; A selection means for selecting a font size setting means that can be displayed to fill the screen from among the font size setting means 2, a refresh memory for storing character string data to be displayed, and a character generation means for storing character shape data of a plurality of sizes. and reading means for reading character shape data of the character size set by the first or second character size setting means according to the character string data in the refresh memory from the character generation means and providing it to the screen display means; When the font size setting means is selected, the font size set by the first font size setting means and the second font size setting means are selected.
cursor position correction means for detecting the difference in the number of dots from the character size set by the character size setting means and correcting the cursor position based on this difference in the number of dots;

[Operation of the Invention] The present invention having the above configuration includes a plurality of character size setting means for setting a character size that allows various character string data to be displayed on the entire screen. That is, the font size setting means includes a font size setting means set by an application program and a font size setting means setting a font size matching the resolution of the display panel. When displaying text in a font size other than that set by the application program on the screen display means, use the selection means to select a font size setting means that matches the resolution of the screen display means, and read out the selected font size setting in the reading means. Predetermined character shape data is read from the character generating means at the character size set by the means. This read character shape data is given to screen display means. Then, the cursor position correction means detects a difference in the number of dots between the character size selected by the first character size setting means and the character size set by the second character size setting means, and the cursor position correction means detects a difference in the number of dots between the character size selected by the first character size setting means and the character size set by the second character size setting means. By correcting the number of lines, the cursor is set at a position that matches the display resolution of the display panel. This cursor position data is also given to the screen display means. By displaying text on the screen display means with a character size and number of cursor lines corresponding to the display image resolution, one page of displayed text and cursor lines fill the entire display screen.

[Example] Hereinafter, a text display device according to the present invention will be described in detail.

FIG. 1 is a block diagram of a personal computer as a text display device, and FIGS. 2, 3, 4, and 5 are block diagrams showing details of each part.

Referring to the figure, the input source circuit 1 includes an address bus 2,
A data bus 3 is connected, and both the address bus 2 and the data bus 3 are connected to a memory address setting circuit 4, a first character size setting circuit 5, and a first character size setting circuit 5 and a second character size setting circuit 6. A selector 7, a protect circuit 8, and a cursor generation circuit 9 are connected.

Further, an address selector 10 is connected to the address bus 2, and a refresh memory 11 is connected to the data bus 3.

As shown in FIG. 2, the input source circuit 1 consists of a memory 1b storing an application program for displaying text and a program for displaying text to fill the entire screen according to the display resolution of the display panel 16, and a keyboard. It consists of an IC, a clock, a disk drive, an interface 1d that inputs and outputs interrupt signals from the light ben, etc.

This input source circuit 1 receives the code and address of a character string for one page of text read from an interface 1d via a data bus 3 and an address bus 2 to a memory address generation circuit 4, a first character size setting circuit 5, a selector 7, It is applied to the protection circuit 8.

Further, the address is given to the address selector 9, and the character code is given to the refresh memory 11.

Memory address generation circuit 4 receives a synchronization signal from synchronization signal generation circuit 12 and a signal from display timing generation circuit 13, and converts the address given from input source circuit 1 into an address corresponding to a display position on display panel 16.

That is, a display address for specifying a line or column is generated, and this display address is given to the address selector 10 and the character generation circuit 14.

The address selector 10 corresponds to reading means, and responds to writing or reading from the input source circuit 1.
, and provides it to the refresh memory 11. Refresh memory 11 is address selector 10
The data for one page of text input via the data bus 3 is written to the address sent from. Further, when displaying characters, a display address from the memory address generation circuit 4 is selected and applied to the refresh memory 11 and the character generation circuit 14. As a result, the refresh memory 11 provides the stored character code to the character generator 14. That is, the code in this case is an address indicating the type of character, and the type of character to be displayed is set by this address.

As shown in FIG. 3, the protect circuit 8 includes an address decoder 8a, a data decoder 8b, and a sequence circuit 8c.
It consists of a SAND circuit 8d and the like, and allows writing of a character size in the second character size setting circuit 6 only when a character size matching the resolution is specified from the input source circuit 1. More specifically, the output of the address decoder 8a goes high only when the address of the protect circuit 8 and the address of the second character size setting circuit 6 are input from the input source circuit 1 via the address bus 2. In other cases, it becomes "L". The output of the data decoder 8b becomes "Hl" only when specific data is input, and becomes "Lo" otherwise. Sequence circuit 8c
The output becomes "H" when the output of the address decoder is "Ho" and when the output of the data decoder 8b becomes "Ho" twice in a row, and the output of the address decoder 8a becomes "H".
When it goes to Lo, it immediately goes to "L". Therefore, the address passes to the output of the AND circuit 8d only when the output of the sequence circuit 8C is "H", that is, only immediately after specific data is written into the protect circuit 8 twice in succession. As a result, the address of the second character size setting circuit can be set, and data can be written to the second character size setting circuit 6.

After that, if an address other than the protect circuit 8 or the second character size setting circuit 6 is set, the sequence circuit 8
The output of C becomes "Lo", and writing to the second character size setting circuit 6 becomes impossible.

Note that the protect circuit 8 is released when the output of the data decoder 8b is "H" twice in a row, but this is because the application program writes data to the second character size setting circuit 6 at system startup. This is to ensure that this is prevented. However, if speed is preferred over reliability, the protect circuit 8 may be released when the output of the data decoder 8b is "H" once.

FIG. 4 is a block diagram showing the relationship between the first character size setting circuit 5, the second character size setting circuit 6, and the character generation circuit 13. Referring to the figure, first character size setting circuit 5,
Both the second character size setting circuit 6 and the address decoder 5
an address decoder 5 of the first character size setting circuit 5.
a decodes the address from the input source circuit 1 and supplies it to the start address setting register 5b. The data from the input source circuit 1 is written into the start address setting register 5b. This data is given to the character generation circuit 13 as the start address of the character to be read out. Further, the address decoder 6a of the second character size setting circuit 6 decodes the address from the protect circuit 8 and supplies it to the start address setting register 6b. Start address setting register 6b
is the input source circuit 1 which is input via the protect circuit 8
Write data from. This data is the character generation circuit 13
It is applied to the character generation circuit 14 via the selector 7 as the start address Al11 of the character to be read out. That is, the first character size setting circuit 5 is a register in which the character size in one page of text is written by the application program of the input source circuit 1, and the second character size setting circuit is activated when the input source circuit 1 starts up the system. This is a register in which the font size that allows one page of text to be displayed on the entire screen of the display panel 16 is written.

The character generation circuit 14 is a ROM that stores character shape data (dot patterns) in a plurality of sizes, and the first or second character size setting circuit 5.6 sets the first address 80, A. The character type is set according to the character code from the refresh memory 10, and further,
A line is set by the address from the memory address generation circuit 4. Addresses 0 to N in the figure refer to the refresh memory 10 and the memory address generation circuit 4.
This is the address specified by . The stored character shape data is output to the video circuit 15 according to the above-mentioned start address, character type, and line address. The contents stored in this character generation circuit 14 will be explained in more detail. For example, character patterns of various sizes, such as a character font of 8x8 dots and a character font of %8x19 tod, are stored, and the 8x8 dot size is the character size set as is in the application program. In addition, the 8 x 19 dot character font is a previously developed 8 x 8 dot character font (640 x 200 dot display resolution, 1
page 80 x 25 characters) on the display panel 16 (64
(0x480 dots) is used to display the entire screen. According to this, 80 x 25 characters of text can be converted into 64 characters.
It can be displayed as 0x475 dots. Note that the above font size is an example, and other font sizes may be stored in correspondence with various types of text.

FIG. 5 is a block diagram showing details of the cursor generation circuit 9. Referring to the figure, the vertical dot number difference detection circuit 9
a compares the character size of the second character size setting circuit 6 set at system startup with the character size of the first character size setting circuit 5 set by the application program, and calculates the difference in the number of dots in the vertical direction. It is something to detect. This detected difference in the number of dots in the vertical direction is calculated by the line number correction circuit 9e.
given to. The cursor display position setting register 9b is a register for setting at which character position the cursor is to be displayed, and the cursor display line number difference setting register 9C is a register for setting at which line in the character box the cursor is to be displayed. Cursor display position setting register 9b
, data is written into the cursor display line number setting register 9C from the input source circuit 1 via the address bus 2 and data bus 3. The data output of the cursor display position setting register 9b is input to the address comparison circuit 9d. On the other hand, the address comparison circuit 9d receives the address indicating the display character position from the memory address generation circuit 4, and when the data in the cursor display position setting register 9b matches the currently displayed character position, the output becomes "H rubel". If there is a mismatch, the data output from the cursor display line number similar register 9C is input to the line number correction circuit 9e.The line number correction circuit 9e converts this data into a vertical dot number difference. The number of lines is corrected based on the difference in the number of dots from the detection circuit 9a, and the corrected data is input to the line number comparison circuit 9f.

Further, the line number comparison circuit 9f receives an address indicating the number of display lines from the memory address generation circuit 4, and when the data of the line number correction circuit 9e matches the currently displayed line number, the output is "H".

If there is a mismatch, the level becomes "L". The outputs of the address comparison circuit 9d and the line number comparison circuit 9f are input to an AND gate 9g, and the output thereof is input to the video circuit 15. Therefore, the output of the AND gate 9f is at the "H" level only when the number of display lines at the character position where the cursor is to be placed is at the "L" level, and at other times it is at the "L" level and serves as a cursor display signal.

More specifically, for example, if the application program sets 8x8 dots in the first character size setting circuit 5 and 8 lines in the cursor display line number setting register 9b, the display resolution of the display panel 16 is 640 dots x 480 dots. On the other hand, 8×19 dots are set in the second character size setting circuit 6 at the time of system startup. In this case, the vertical dot number difference detection circuit 7a detects a difference of 11 dots between 8 dots and 19 dots, and inputs correction data of 11 dots to the line number correction circuit 9e. On the other hand, since the output of the cursor display line number setting register 9C is 8 lines, the output of the line number correction circuit 9e is 8+11-19 lines. Therefore, the text display and cursor display are corrected as shown in FIGS. 6(a) to 6(b). That is, the contents of the 8x8 dot character box (8x6 dot characters, 8th line cursor) are displayed in the 8x19 dot character box with 8x16 dot characters and 19th line cursor.

The video circuit 15 performs parallel/direct conversion on the character shape data output from the character generation circuit 14 together with the cursor display position data corrected by the cursor generation circuit 9 at a timing synchronized by a synchronization signal, and converts the character shape data to the display panel. 1
Give to 6.

The operation of the text display device shown in FIG. 1 will be explained below with reference to the flowchart shown in FIG. In addition, in this operation, the display resolution of the software is 640 x 200 dots, 8 x 8 dots per character, and 80 x 25 lines per page.
Using the dot display panel 16, 80 × 19 dots
Let us take as an example the case of displaying with X25 characters. First step S
1, the input source circuit 1 reads one page of text,
It is determined whether the image should be displayed in 8×8 dot size or 8×19 dot size. If it is determined that the image should be displayed in 8×8 dot size, an application program is called in step S6. On the other hand, if it is determined that the character should be displayed in 8×19 dots size, in step S2, data for setting the second character size setting circuit 8 to 8×19 dots is output to the protect circuit 8, and the protect circuit 8 is unlock.

In step S3, data for setting the character size to 8×19 dots from the input source circuit 1 is written to the second character size setting circuit 6.

In step S4, after data has been written to the second character size setting circuit 6, the protect circuit 8 is set to prohibit writing to the second character size setting circuit 6.

In step S5, the first character size setting circuit 5,
The character size is compared with that of the second character size setting circuit 6, and the number of lines is set based on the difference in the number of dots in the vertical direction. This is performed by operating the vertical dot number difference detection circuit 9a and the line number correction circuit 9e.

The application program is called in step S6.

In step S7, the application program is operated.

That is, data for one page of text is written into the refresh memory 11 according to the application program, and character shape data of 8×19 dot size is read out in accordance with the written character string data.

Also, cursor position data (line 19 is read out).

The above application program is a program that reads character shape data of 8×8 dot size and sets the cursor position to the 8th line.
The character size setting circuit 6 is set to 8×19 from the character generation circuit 14.
Since the start address is set to A□ to read the dot-sized character shape data, the refresh memory 11
The character shape data read out according to the address from the memory address setting circuit 4 and the line address from the memory address setting circuit 4 has a size of 8×19 dots. Furthermore, since the cursor line number is set to the 19th by the cursor generation circuit 9, the cursor position is displayed on the 19th line of the character box. The read character shape data and cursor display position data are applied to the video circuit 15.

Next, the video circuit 15 converts the character shape data and cursor display position data provided from the character generation circuit 14 into
It is directly converted and provided to the display panel line by line. The display panel 25 displays one line at a time based on the signal supplied from the video circuit 14, and finishes displaying one page when 25 lines have been displayed.

As described above, one page of 80x25 characters of text and a cursor can be displayed on the entire screen with a display resolution of 640x480 dots.

In the above example, the font size is changed vertically (8 dots → 19 dots).
Although we have explained the method using dots, it is also effective to expand the font size horizontally. For example, in an application program, if a character pattern of 8 dots x 8 dots is arranged horizontally for 80 characters, the horizontal resolution is 640 dots, but the horizontal resolution of the display panel used is 72 dots.
In the case of 0 dots, a remainder of 80 dots will appear. Therefore, if the character size setting circuit 61 sets a font size of 9 dots x 8 dots, the characters displayed on the display panel will be
9 dots x 80 characters - 720 dots, which fills up the display panel in the horizontal direction as well. As described above, the present invention can also accommodate enlargement of character size in the horizontal direction. It goes without saying that the length of the cursor can also be changed as the font size is changed.

[Effects of the Invention] According to the present invention, the character generation means stores character shape data of a plurality of sizes, and the character size setting means sets the character size in accordance with the resolution of the screen display means. By setting a font size other than the font size set by , text can be displayed to fill the entire screen of the screen display means without impairing the versatility of the application program. Furthermore, when the font size is changed, the difference in the number of dots between the font sizes set by the first font size setting means and the second font size setting means is detected, and the line is adjusted based on this difference in the number of dots. By correcting the number, the cursor can be displayed at a position corresponding to a change in character size without impairing the versatility of the application program.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a text display device according to the present invention, FIG. 2 is a block diagram of an input source circuit, and FIG.
The figure is a block diagram of the protect circuit, Figure 4 is a block diagram explaining the relationship between the first character size setting circuit, the second character size setting circuit, and the character generation circuit, and Figure 5 is the 7th diagram of the cursor generation circuit. 1 is a flowchart for explaining the operation of the text display device of FIG. 1, and FIG. 8 is a diagram for explaining that the non-display portion becomes large in the conventional text display device. In the figure, 1 is an input source circuit, 4 is a memory address generation circuit, 5 is a first character size setting circuit, 6 is a second character size setting circuit, 7 is a selector, 8 is a protect circuit, 9 is a cursor generation circuit, and 10 is a 11 is a refresh memory, 12 is a character generation circuit, and 16 is a display panel. Figure 2 also appears. Figure 4 Figure 4 Figure 8 Figure 8 Procedural Amendment (Voluntary) April 22B, 1991 ■. Indication of the case Patent application No. 2-21656 2゜ Title of invention text display device 3゜ Person making the amendment Relationship with the case

Claims (1)

[Scope of Claims] Screen display means; first character size setting means that corresponds to the display resolution of the screen display means; and displaying various character string data that does not correspond to the display resolution of the screen display means to fill the entire screen. a plurality of second font size setting means for setting possible font sizes, and a font size setting means that can display the font to fill the screen among the first and second font size setting means depending on the type of character string data. a refresh memory for storing character string data to be displayed; a character generating means for storing character shape data of a plurality of sizes; and a selection means for selecting the first or second character according to the character string data in the refresh memory. reading means for reading character shape data of the character size set by the size setting means from the character generation means and providing it to the screen display means; and a first character size setting means when the second character size setting means is selected. The font size set by
1. A text display device comprising: a cursor position correction means for detecting a difference in the number of dots from the character size set by the character size setting means, and correcting a cursor position based on the difference in the number of dots.