JPH10254426A - Character generation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the character generating method in which the number of display fonts is increased with a simple constitution without greatly changing a conventional display system. SOLUTION: Character fonts are registered by dividing a character generator 10 into a fixed region 10a and an exchanging region 10b. If the characters, which are to be displayed, are registered in the fixed region, the display code, which indicates the position in the generator, is written into a VRAM. If the characters are not registered, a character font is obtained from a memory 22 and is registered in the region 10b. By controlling the character font registered in region 10b and its display code and dynamically exchanging the character font in the region 10b, the apparent number of fonts, which are registered in the generator 10, is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a character generation method, and more particularly to a character generation method capable of expanding the number of registered fonts by dynamically replacing fonts.

[0002]

2. Description of the Related Art Conventionally, in a data entry system (data input device), a font (character pattern) is registered in a portion called a character generator, and when a font display request is made by a key input from a keyboard, for example, a VRAM is called. Characters and symbols can be displayed on the screen by writing a display code corresponding to a font for which a display request has been made into hardware resources.

In this case, in the character generator of the data entry system, the font registration range of the user is from 8080 to FFFFh, of which 5486 can be registered, and the number of fins that can be used is limited.

[0004]

However, there is a tendency for the number of characters, symbols, and the like to be expressed to increase, and accordingly, there is a demand for increasing the number of registered fonts. However, the character generator in the font registration area that affects the number of registered fonts is a hardware resource, and the registration area has a limit. In order to increase the number of registered fonts, the capacity of the character generator may be increased. In this case, not only does the cost of the character generator itself increase, but also the V
There is a problem that the conventional display system up to the RAM and the monitor must be largely changed in hardware and software.

Accordingly, the present invention has been made to solve such a problem, and it is possible to increase the number of character fonts that can be registered with a simple configuration without greatly changing the conventional display system. It is an object to provide a possible character generation method.

[0006]

According to the present invention, an object of the present invention is to divide a character generator into first and second areas and to convert a predetermined number of character fonts into the first one.
If the character font to be displayed is registered in the memory, the character font is registered from the memory to the second area. And the correspondence between the registered position and the character font is performed.
The problem is solved by a character generation method characterized in that a character font to be displayed is generated from the first or second area.

[0007] A predetermined number (4486) of fonts are registered in the first area of the character generator, and the correspondence between the registered positions and the character fonts does not change. Therefore, the first area is a fixed area. In the second area,
Fonts registered in other storage media (memory) are registered as other fonts not registered in the first area.
If the character font to be displayed is registered in the memory, the character font is registered in the second area from this memory. At this time, the correspondence between the registered position and the character font is managed through a table or the like, The registered character font in the second area can be dynamically replaced. Therefore, the character fonts registered in the memory can be replaced and registered in the second area. By increasing the number of fonts registered in the memory, the number of fonts that can be registered in the character generator is apparently increased. be able to.

When registering a character font in the second area (replacement area), the character font is registered in a position that has not been associated yet. The greater the number of uncorrelated positions, the greater the possibility of replacement. Therefore, if a correlated character font is displayed at the position to be displayed (VRAM, screen position), The display is performed after the association is canceled. Further, when the displayed characters are cleared or when the displayed characters disappear from the screen due to scrolling, if the character font at the display position is the character font with the association, the association is canceled. By these measures, the second region can be opened.

The correspondence between the registered position of the second area and the character font is determined by, for example, displaying a display code indicating the registered position, the character code of the registered character font, and a flag indicating that the association is associated with a table format. It can be done by managing with. Normally, a display code is written in the VRAM, and the character generator is accessed via the display code to display a character font.

As the memory capacity is increased, the apparent number of registered character generators is correspondingly increased.
It is preferable that the capacity of the memory can be set by user setting. Thus, a user who does not need the number of registrations unnecessarily can use the memory for another use.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

[Principle] FIG. 1 illustrates the principle of the present invention.
It is possible to register 16384 fonts in the area of ＦＦFFFFh. Among them, the entry system is a system for fixed registration, JIS font is 108
Since there are 98 fonts and these fonts have already been registered, the remaining 5486 fonts are the maximum number of registered user fonts. Therefore, for example, as shown by 20, when the number of registered user fonts is 10,000, 8080 to 8080
It is impossible to register all of them in the area of FFFFh.

Therefore, in the present invention, the registration area of this character generator is replaced with the fixed area 10a and the replacement area 1
0b, and the number of fonts that can be registered in the character generator is increased by dynamically switching the fonts registered in the replacement area 10b.

For example, if the number of registered user fonts is 10,000
If there are 448 user fonts in the fixed area 10a
Register up to six, and secure an area for 1000 fonts in the replacement area. Next, the remaining 5514 (= 10000-4486) fonts 2 not registered in the fixed area
1 is stored in the memory 22. If there is a request for displaying 5514 fonts, the fonts are dynamically replaced and registered in the replacement area 10b for 1000 fonts and displayed.

[0015] In this way, 54
87 to 10000 fonts from 8080 to FFFFh
, It is possible to increase the number of registered user fonts to 10,000.

[Details of Function] Resources required for character generation by this dynamic font switching include existing character generator and VRAM hardware resources,
There are three new resources to be added: a replacement font table, a code management table, and a replacement code management table. These are added to a memory and managed by software. The following describes each resource.

The character generator (CG) is 80
It is a hardware resource that manages the font registration area of 80 to FFFFh. As shown in FIG.
A font is registered in an area of 0 to FFFFh, and in the embodiment of the present invention, is divided into a fixed area 10a and a replacement area 10b.

VRAM is a normal video RAM,
It is a hardware resource that manages a display code (refer to a character code and a display code) of a font to be displayed on a screen. Display of the font on the screen is realized by writing a display code obtained by converting a character code according to a certain conversion rule into a VRAM.

The replacement font table 30 manages the character code (2 bytes) and the address (4 bytes) of the font registered in the replacement area 10b of the character generator 10 as shown in FIG. It has a data area for the remaining 5,514 characters of the font number (4486) already registered in the fixed area 10a out of the font number (10000).

The font file 36 shows the correspondence between the font address of the replacement font table 30 and the actual font data (bit map of 72 bytes) registered therein.

The code management table 32 has 4486 registered in the fixed area 10a of the character generator 10.
It is a table for managing character codes (2 bytes) and display codes (2 bytes) of the fonts. Since this table manages the fixed area 10a, the correspondence between the character code and the display code is established, and does not change. Therefore, the contents of the font of the display code in the fixed area can always be known through the code management table 32.

On the other hand, the replacement code management table 34
Is the replacement area 10b of the character generator 10.
Manages the character code (2 bytes) and display code (2 bytes) data of the font registered in. The number is 1000 corresponding to the number of replaceable areas that can be registered. In the screen display management area 34a of the replacement code management table 34, information as to whether or not the font indicated by the character code is displayed on the screen is input. When not displayed, flag = 0 is registered, and when displayed, flag = 1 is registered.

In the replacement code management table 34, unlike the case of the code management table 32, the correspondence between the character code and the display code dynamically changes according to the replacement. When the flag = 1, the display code and the character code can be associated with each other, and when the flag = 0, the association is released.

According to the present invention, when a character font which is not in the fixed area is to be displayed, a search is performed for a flag = 0, and if found, a character code is associated with the display code, and the character code is assigned to the display code position of the replacement area. The font corresponding to the character code is registered, and at that time, the flag is changed from 0 to 1 to determine the relationship between the character font registered in the replacement area of the character generator and the registration position.

In the present invention, the character code is
This refers to a code corresponding to 72-byte character font data. On the other hand, the display code is a code corresponding to the registration position when font data is registered in the character generator. For example, as shown in FIG.
Assuming that the font “Chinese” with a character code of 7070h is registered at the position of FFA0h of the character generator, the character code is 7070h and the display code is FFA0.
h.

[Registration of User Font to Character Generator] Next, the flow of registration of a user font to the character generator will be described with reference to FIG.

First, in step S1, when the driver is initialized, the display code of the replacement area 10b of the character generator 10 is input to the display code of the replacement code management table 34. For example, if the replacement area 10b is F5D8 to FFFFh, these display codes are sequentially registered in the display code column of the replacement code management table 34. At this time, since the screen has not been displayed yet, the flag = 0 is input to the screen display management area 34a of the replacement code management table 34 (step S2).

When performing registration, registration is performed from the head [80A0h] of the user font registration area of the character generator. This is performed by acquiring the font to be registered from the font data (step S3) and registering the font data in order from [80A0h] of the character generator (step S5).

Since [FFA0h] is a fixed area, a character code and a display code are registered in the code management table 32 of FIG. 2 for each registration (step S6). For example, when the character code of the first font is [0001], the character code [0001] and the display code [80A0h] are registered in the first table 32.

In the fixed area of the character generator,
Since up to 4486 characters can be registered, the above steps are repeated for that number. If it is determined in step S4 that the font is the font after the 4487th character, the process proceeds to step S7, and the font is registered in the font data area (font file). This is performed by registering font data (72 bytes) at each address of the font file 36 in FIG. At this time, the font address and the character code are input to the replacement font table 30 (step S8).

The registration of the font data in the font file 36 and the input to the replacement font table 30 are performed for 5514 fonts. If it is determined in step S9 that all the font data has been registered, The process ends.

The above-mentioned replacement font table 3
0, the code management table 32, and the replacement code management table 34 are managed by the console driver. Further, each table and font file may be stored in one memory, or may be stored individually in each memory.

[Character Display] Next, character display using the character generator in which the font is registered as described above will be described.

Steps S10 to S14 in FIG. 4 are performed when the display code is written to the VRAM to display the character, and when the display code of the VRAM at the current writing position is the display code of the replacement area, the display code is displayed. Is set to 0.

First, in step S10, a display code is obtained from the code writing position of the VRAM. In step S11, it is determined whether or not a double-byte display code (the double-byte code is 4 bytes and a null code is input in the latter 2 bytes). In the case of a half-width code, since it is registered in the fixed area and is not a display code of the replacement area, the process branches from step S11 to step S15.

On the other hand, if it is a double-byte display code, the replacement code management table 34 is searched (step S1).
2). In step S13, if there is no hit,
Since the display code is for the fixed area, the process similarly branches to step S15. On the other hand, when the display code is searched in step S13, 0 is set in the screen display management area 34a of the replacement code management table 34 (step S14). This process is always performed when the display code is written in the VRAM. As a result, a place where the screen display management area of the display code of the replacement area is 0 can be created, and the font of the position of the replacement area corresponding to the display code can be replaced.

When the above processing is completed, a character code is obtained from the upper module received from the application (step S15). If the character code is a system or JIS code (steps S16 and S16)
17) Since the corresponding display code has been determined, the display code is written to the VRAM in step S21.

On the other hand, if the character code is not the system or JIS code, the code management table 32 is searched with the character code in step S18. If it is determined in step S19 that a hit has occurred,
In step S20, the display code is converted into a display code corresponding to the character code, and in step S21, the display code is written in the VRAM.

This state is shown in FIG. For example, when the character code = 0001 is passed from the application, since the character code is registered in the code management table 32, the search is hit, and the corresponding display code = 80A0 is written to the VRAM 40. When a hit is found in the code management table 32, it means that the font corresponding to this character code is registered in the fixed area of the character generator, so that the font is not registered in the character generator.

On the other hand, if it is determined in step S19 that no hit has occurred in the code management table 32, the replacement font table 30 is searched in step S22. For example, when the character code = 7070 is passed from the application, the character code hits in the replacement font table 30 (step S23), and at that time, the font address corresponding to the character code is acquired (step S24). This state is shown in the upper part of FIG. 6, and the font address = 1000 is obtained from the character code = 7070 by the replacement font table 30.

Next, in step S25, a search is made for one in which the screen display management area of the replacement code management table 34 is set to 0 (not displayed on the screen). If a hit is confirmed in step S26, a display code is obtained. For example, as shown in the middle left part of FIG. 6, when searching for the fact that the screen display management area 34a of the replacement code management table 34 is 0,
Since the display code = FFA0 is 0, the display code is obtained.

Next, when the display code is obtained as described above, the screen display management area 34a corresponding to the display code is set to 1 in steps S27 and S28, and the character code is set in the character code area. 707
0 is set (see the replacement code management table at the lower left of FIG. 6).

Subsequently, in step S29, VRA
The display code is written into M40, and the font indicated by the font address is registered at the position of the character generator 10 indicated by the display code. Referring to FIG. 6, the display code = FFA0 is set in the VRAM 40, and the font data “han” corresponding to the address = 1000 of the font file 36 is registered at the position of FFA0 of the character generator 10.

On the other hand, if no hit is found in step S26, the code is converted to a Hex display code because the font is not assigned (step S30). If there is no hit, since the number of displayed dynamic fonts exceeds 1000, it is converted to Hex display code.

[Character Deletion] Next, character deletion will be described.

Character deletion is performed by inputting 4040h (space code). When there is a request to delete characters, as shown in step S40 of FIG. 7, the display code of the writing position of 4040h of the VRAM 40 is obtained. If it is determined in step S41 that the code is a full-width display code, the replacement code management table 34 is searched with the display code (step S42).

If a hit is confirmed in step S43, 0 is set in the screen display management area (step S44). Subsequently, in step S45, 4040h (space code) is written to the VRAM. For example, as shown in FIG. 8, when the display code of the VRAM 40 at the position where 4040h is written is FFFF, the display code = FFFF is obtained, the replacement code management table 34 is searched with this code, and A certain screen display management area 34a is set to 0.

On the other hand, if no hit is found in step S43, since it is a display code for a system font or a fixed area, 4040h is written to the VRAM as it is.

[Scroll] Next, a description will be given of character display when the screen is scrolled.

As shown in FIG. 9, the VRAM 40 has a larger capacity than the screen display area 40a. In the case of a font in the replacement area, a display code is basically allocated in the screen display area 40a. On the other hand, in other areas, character codes are assigned. this is,
If display codes are assigned to areas other than the screen display area, all display codes in the replacement area (1000)
Is assigned, and it becomes impossible to display a dynamic font by replacement.
Therefore, when leaving the display area, the display code is converted into a character code, and in the case of the replacement area display code, the screen display management area is set to 0,
Conversely, when entering the screen area, the character code is converted into a display code, and when the display code is in the replacement area, the screen display management area is set to 1.

First, as shown in step S50 of FIG. 10, if there is a request to scroll the screen,
The display code is acquired from the head of the VRAM line that disappears from the screen by scrolling, and if it is a full-width display code, the full-width display code is acquired.

Subsequently, in step S51, the code management table 32 is searched. If a hit is confirmed in step S52, the display code is converted to a character code in step S56.

On the other hand, if there is no hit, step S
At 53, the replacement code management table 34 is searched. If there is a hit, the display code is converted to the corresponding character code, and the corresponding screen display management area 34a is set to 0 (steps S55 and S55).
56).

Subsequently, the character code obtained as described above is written into the VRAM (step S57), and the above steps are repeated for the entire search range (step S58).

The above state is shown in FIG. 11, for example, in the line which is erased from the screen of the screen display area 40a before scrolling of the VRAM, for example, the display code = 808
Assume that A and FFA0 have been written. Display code =
If 808A is acquired, the code management table 3
2, the character code is 0001, and when the display code is FFA0, the replacement code management table 34 is hit, and the corresponding character code = 7070 is extracted. At that time, the screen display management area 34a is set from “1” to “0”.

Next, the process in which scrolling is advanced and what has not been displayed on the screen until now is displayed on the screen is illustrated after step S59 in FIG.

For a line displayed on the screen, a code is obtained from the head of the line displayed in the same manner as a line that disappears from the screen, and if it is a full-width character code, this full-width code is obtained (step S59). When a full-width character code is obtained, a display code is obtained through a character code → display code conversion routine (step S60). Although this conversion routine is not shown, steps S51 to S51
56 corresponds to the reverse conversion from the display code to the character code. Thus, when the display code is obtained, the code is written in the VRAM display position (step S61).
This is repeated for the entire search range (step S
62).

For example, in FIG. 11, when scrolling proceeds and character code = 0001 is acquired, display code = 808A is obtained via code management table 32, and this is written to the VRAM.

[Screen Clear] Screen clear corresponds to performing the character deletion described with reference to FIG. 7 for the characters on the entire screen. To delete characters, clear the code on the screen currently displayed on the screen (404 in the VRAM screen display area).
0h), so 4h from the top of the screen
Obtain the display code of the position to write 040h (FIG. 1
2 step S70).

If it is determined in step S71 that the code is a double-byte display code, the replacement code management table 34 is searched with the display code (step S72). If a hit is confirmed in step S73, the screen display management area corresponding to the code is set to 0 (step S7).
4) Then, 4040h is overwritten on the VRAM (step S75).

This state is shown in FIG. When clearing is started and, for example, the full-size display code FFA0000 is written in the screen display area of the VRAM 40, the display code = FFA0 is obtained, and the replacement code management table 34 is searched and hits.
The screen display management area is set to 0, and 4
040 has been written.

On the other hand, if the code is not a full-width code in step S71 or if no hit is made in step S73,
Since it is not the display code of the replacement area,
0h is overwritten and the process is performed for a range in which this process is cleared (step S76).

[VRAM Read] When an application accesses the VRAM and knows what kind of character is written in the VRAM, a VRAM read (read) request is issued. The flow at that time,
As shown in FIG. 14, when a VRAM read is requested, one code in the read range is read (step S80). It is confirmed whether or not the code is a full-width code (step S81). If the code is a full-width code, the routine goes through a routine for converting the display code into a character code as in scrolling.

That is, the code management table is searched in step S82, and if a hit is confirmed in step S83, the display code is converted into a character code according to the code management table (step S84). The replacement code management table is searched (step S85). If a hit is found in the replacement code management table in step S86, step S8
In step 7, the display code is converted into a character code according to the replacement code management table. Note that, unlike the case of scrolling, the screen display management area is not set to 0 at this time.

Next, in step S88, the converted code is written in a character code string to be passed to the application. This is performed for the read range (step S8).
9). When the read range is completed, the read range is passed to the application that made the read request as before.

FIG. 15 shows this state. For example, when the read range of the VRAM is 40c, for example, when the full-width code = FFA0 is written, the character code = 7070 according to the replacement code management table.
Is obtained, and is written in the character code string 50 to be passed to the application.

[VRAM Write] Next, the case where a write (write) request is made in reverse to the read from the application will be described with reference to FIGS.

First, one code at the VRAM write position where the character code string received from the application is to be written is read, and it is checked whether the code is a full-width code (steps S90 and S91). If the code is a full-width code, the replacement code management table 34 is searched (step S).
92).

If a hit is confirmed in step S93, the screen display management area is set to 0. This is shown in FIG.
When the character is displayed, the display code is set to 0 and the display code is released in the same manner as shown in steps S11 to S14.

Thereafter, in step S95, a character code is obtained from the character code string passed from the application, and if the character code is a full-width code (step S96), the character code is passed through a character code → display code conversion routine. The code is converted into a display code (step S97), and the code is written into the VRAM (step S98).

If the result of the determination in steps S91 and S93 is negative, the process proceeds to step S95 because the display code is not the replacement area display code. If the result of the determination in step S96 is negative, the display code is determined. The process directly proceeds to step S98.

The above steps are performed until the write range ends (step S99).

FIG. 17 shows an example described above.
For example, in the light range 40d, the display code of the VRAM = F
When FB00000 is acquired, a hit is made in the replacement code management table 34, so that the display code = FFB0
Is set to 0 in the screen display management area. When the character code of the light is 7070 as shown in the lower part of FIG. 17, the display code is acquired from the character code by the display code conversion routine. Display code = FFA0 flag is 0 when searching in replacement code management table
Therefore, the display code = FFA0 is obtained and the VRA
The display code is written in M.

[Reading of Character Generator] Reading of the character generator is a case where the character generator is directly accessed to obtain a font without going through the VRAM. The flow in that case is shown in FIG.

First, when the application requests a read of the character generator, step S1
At 00, the replacement font management table is searched by the character code. If a hit is confirmed in step S101, the process jumps to step S108 to acquire a font address and pass it to the application (step S109).

On the other hand, if no hit is found, the font is outside the replacement area, and the code management table is searched using the character code (step S102). If a hit is confirmed here (step S103), the font is a fixed area font. In step S106, the character code is converted into a display code to obtain a font address.

On the other hand, if there is no hit in step S103 and there is no hit in either table, it is a system, JIS code or a code without font allocation, so it is checked in steps S104 and S105. If the system is JIS code, step S107
To get the font address from the display code. Also,
If the font is unassigned code, return a white font to the application.

If the system is not a JIS code, an error code is set in step S110.
As described above, according to the present invention, the character fonts in the replacement area can be dynamically replaced, so that the number of registered fonts can be increased by extending the user font registration range. However, as shown on the left side of FIG. 19, it is apparent that the registration range is expanded, and the actual registration is in the range of 8080 to FFFFh on the right side. , Is secured and managed on the memory (font file) and displayed on the screen.

Note that, depending on the number of fonts registered by the user,
Since the capacity of the memory is different, a dip switch that can be operated by the user is set, and the memory can be obtained step by step. This makes it possible to save the memory usage of the system.

That is, as shown in FIG. 20, by setting the dip switch according to the number of registered user fonts, the memory is obtained step by step. The DIP switch can be set in 11 steps from 0000 to 1010, and after 1011, the setting is the same as 1010. In this case, even if an attempt is made to register more fonts than the set registration number, the font is ignored and not registered.

[0081]

As described above, according to the present invention,
The character generator is divided into a fixed area and a replacement area, and by managing the character font registered in the replacement area and its display code or registered position, it becomes possible to dynamically replace the character font in the replacement area. The number of fonts that can be registered in the generator can be apparently increased.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating the principle of the present invention.

FIG. 2 is an explanatory diagram showing a relationship between various tables or files and a character generator.

FIG. 3 is a flowchart showing a process of registering font data in a character generator.

FIG. 4 is a flowchart illustrating a flow in which characters are displayed.

FIG. 5 is an explanatory diagram showing a state in which characters in a fixed area are displayed.

FIG. 6 is an explanatory diagram showing a state in which a character font is registered in a replacement area.

FIG. 7 is a flowchart showing the flow of deleting characters.

FIG. 8 is an explanatory diagram showing a state when characters in a replacement area are deleted.

FIG. 9 is an explanatory diagram showing a screen display area of a VRAM and other areas.

FIG. 10 is a flowchart showing the flow when scrolling the screen.

FIG. 11 is an explanatory diagram showing VRAM code conversion when the screen is scrolled.

FIG. 12 is a flowchart illustrating a flow when the screen is cleared.

FIG. 13 is an explanatory diagram showing a relationship between a VRAM and a table when a screen is cleared.

FIG. 14 is a flowchart showing the flow of a VRAM read.

FIG. 15 is an explanatory diagram showing a state in which a VRAM is read and passed to an application.

FIG. 16 is a flowchart showing the flow of a VRAM write.

FIG. 17 is an explanatory diagram illustrating a VRAM write process.

FIG. 18 is a flowchart showing a flow of accessing a character generator to obtain font data.

FIG. 19 is an explanatory diagram showing a state where the registration range of the character generator is apparently expanded according to the present invention.

FIG. 20 is a table showing a state in which the capacity of a memory in which fonts are registered is changed by setting a dip switch.

[Explanation of symbols]

 10 Character Generator 10a Fixed Area 10b Replacement Area 30 Replacement Font Table 32 Code Management Table 34 Replacement Code Management Table 36 Font File 40 VRAM

Claims (5)

[Claims] 1. A character generator is divided into a first area and a second area. A predetermined number of character fonts are registered in the first area, and other fonts are registered in a memory different from the character generator. If the character font to be displayed is registered in the memory, the character font is registered from the memory in the second area, and the registered position is associated with the character font. A character font to be generated from the first or second area. 2. The character generation method according to claim 1, wherein when registering the character font in the second area, the character font is registered at a position where no correspondence has been made yet. 3. When a character font having the association is displayed at a position to be displayed, the character to be displayed is registered and read out from the character generator after the association is released. 3. The character generation method according to claim 1, wherein: 4. When the displayed character is cleared, or when the displayed character disappears from the screen by scrolling, and the character font at the display position is the character font with the association, the association is canceled. The method according to claim 1, wherein the character is generated. 5. The character generating method according to claim 1, wherein the memory capacity is changed according to the number of registered character fonts.