JPH058644U - Computer equipment - Google Patents

Abstract

(57) [Summary] [Object] To display a character font in a computer device without using a font ROM and without significantly reducing the storage area of the main storage device. A main storage device 4 is provided with a font cache area 4b for loading frequently used character fonts from a hard disk 3 and storing a font table in which character codes and addresses of the character fonts are associated with each other. The cache search unit 1c searches the font table for the character code output from the application execution unit 1a, and determines whether the character font requested to be displayed is in the font cache area 4b. If there is a character font, the font display unit 1e transfers the character font to the display memory 5 and causes the CRT 6 to display the character font. If there is no character font, the font loading unit 1d loads it into the font cache area 4b and then transfers the character font.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a computer device that includes a hard disk that stores character fonts and that displays the character fonts on a display device.

[0002]

[Prior Art]

 Conventionally, a method of displaying a character font in a computer device includes, for example, a method using a font ROM and a method using a main storage device.

In the method using a font ROM, a ROM storing character fonts is incorporated in a computer device in advance, and a font corresponding to a character code requested to be displayed is read from this ROM and displayed on the display device.

In the method using the main storage device, the character fonts are stored in the hard disk, etc., all the character fonts are loaded from the disk to the main storage device at the time of system startup, and then the characters requested to be displayed are displayed. The font corresponding to the code is read from this main storage device and displayed on the display device.

[0005]

[Problems to be solved by the device]

 However, in the case of a font display method using a font ROM, it is necessary to provide a ROM dedicated to the font in addition to the main storage device, etc., which is costly and requires a space for incorporating the ROM, which hinders miniaturization. There is a problem that becomes.

On the other hand, in the case of the font display method by the main storage device, since all character fonts are stored in the main storage device, even character fonts that are very rarely used are stored in the main storage device. There is a problem that a considerable storage area in the main storage device is occupied and the storage area for storing programs and the like is greatly reduced.

Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a computer device that does not use a font ROM and that does not significantly reduce the storage area of the main storage device. To aim.

[0008]

[Means for Solving the Problems]

 In the present invention, in order to achieve the above object, a display device, a hard disk storing a character font and an application program displayed on the display device, and a character font retained when the character font is displayed on the display device. In a computer device having a display memory, a font cache area for storing a frequently used character font loaded from the above hard disk and a font table that associates the character code and address of the character font is provided. A storage device, an application executing means for executing the application program and outputting a character code of a character font to be displayed on the display device, and receiving the character code from the application executing means, and outputting the character code. Font font Cache search means for searching for a character font corresponding to the character code, and if the cache search means does not find a character font corresponding to the character code, the font cache area If there is a space, the character font corresponding to the above character code is loaded from that hard disk to the available space, while if there is no space in the font cache area, it is loaded first. If there is a font loading unit that discards the created character font and creates a space and loads the character font corresponding to the above character code in that space, and a character font corresponding to the above character code in the above font cache area, Based on the address in the font table, the character font is read and the display menu is displayed. Characterized by comprising the font display means for delivering the re.

[0009]

[Action]

 In the above configuration, first, the application executing means outputs the character code of the character font to be displayed on the display device by executing the application program, and the cache searching means receives the character code and stores it in the font table of the main storage device. The presence or absence of a character font corresponding to the character code is determined by searching with.

If the cache search means determines that there is no corresponding character font, then the font loading means determines whether or not there is an empty space in the font cache area of the main storage device. While the character font is loaded into that space from, the character font loaded first is discarded and a space is created, and the character font is loaded into that space.

If there is a corresponding character font in the font cache area, the font display means reads the character font to be displayed based on the address, sends the character font to the display memory, and displays the character font on the display device. Display it.

[0012]

【Example】

 An embodiment of a computer device according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of this computer device and the functions of the CPU.

As shown in the figure, the present device includes a CPU 1, a system ROM 2, a hard disk 3, a main storage device 4, a display memory 5, and a CRT 6 as a display device.

The hard disk 3 stores in advance an application program set by a user or the like, a font display control program, a character font, and the like.

A system program for starting the CPU 1 is stored in the system ROM 2. The CPU 1 executes the system program when the apparatus is started up, so that the application program stored in the hard disk 3 to be described later is stored. The font display control program is loaded into the program storage area 4a of the main storage device 4.

The CPU 1 executes the application program and the font display control program loaded in the main storage device 4, and the application executing unit 1a, the cache searching unit 1c, and the font loading unit corresponding to each component of the present invention. 1d, functions as a font display unit 1e, and also functions as a character code analysis unit 1b described later.

The main storage device 4 is composed of a data rewritable RAM, and has a font cache area in addition to a program storage area 4a for storing normal programs such as application programs and font display control programs and data. 4b is provided.

The font cache area 4b is an area for storing a frequently used character font loaded from the hard disk 3, and a font table in which a character code of the character font and an address indicating a storage location of the character font are associated with each other. Is. Since the type of character fonts used in general documents is about 8000 types of characters that can be displayed, in the present embodiment, the font cache area 4b is about 5 to 10%, which is about 800 characters. Secure.

The display memory 5 is a memory that holds the character font when displaying on the CRT 6.

Next, the operation of the computer device configured as described above will be described with reference to FIG. 2 showing the processing procedure of the CPU. First, the CPU 1 executes an application program and functions as the application execution unit 1a. When a character font display request command is included in the application program, the CPU 1 reads the font display control program from the main storage device 4 and executes it. , The character code analysis unit 1b, the cache search unit 1c, the font load unit 1d, and the font display unit 1e.

That is, when the character code string of the character font to be displayed is sent from the application execution unit 1a to the character code analysis unit 1b, the character code analysis unit 1a analyzes the character code string and The character codes are disassembled (step 100).

The cache search unit 1c receives the character code from the application execution unit 1a via the character code analysis unit 1b and searches the font table in the font cache area 4b of the main memory 4 for the character code (step 200), it is determined whether or not the character font corresponding to the character code is in the font cache area 4b (step 300).

If the character code can be detected in the font table (step 300 “Yes”), it means that the corresponding character font exists in the font cache area 4b, and therefore the font display unit 1e displays the address of the character font. Based on the above, the character font is read from the font cache area 4b, transferred to the display memory 5 and displayed on the CRT 6 (step 400).

This completes the font display processing for one character, returns to step 100 again for the next character font display, and repeats the above processing.

As described above, when a display request for a character font is made, if the character font is stored in the font cache area 4b of the main storage device 4 composed of RAM, the hard disk 3 is accessed one by one. Since there is no need for a font ROM, character fonts can be displayed at high speed.

By the way, if it is determined in step 300 that there is no character code of the corresponding character font in the font table (step 300 “No”), the cache search unit 1c continues to fill the font cache area 4b. It is determined whether or not there is (step 310).

If the font cache area 4b has a free space (step 310 “Yes”), the font loading unit 1d accesses the hard disk 3 to read the character font corresponding to the character code requested to be displayed, Load it to an empty area (step 320).

Then, the cache search unit 1c further updates the font table in accordance with the updated contents of the character fonts in the font cache area 4b (step 330), and then the font display unit 1e reads the character font from the font cache area 4b. Is read and transferred to the display memory 5, and the character font is displayed on the CRT 6 (step 400).

On the other hand, when there is no space in the font cache area 4b (step 310 "No"), the character font loaded first in the font cache area 4b is discarded by one character to make a space ( If there is a space thereafter (step 315), the character font is loaded from the hard disk 3 into that space (step 320), and the font table is updated (step 330). The character font is transferred to the display memory 5 (step 400).

Therefore, even if there is no character font for which a display request has been made in the font cache area 4b of the main storage device 4, it will be stored in the font cache area 4b from the next access of this character font. Since the character fonts are stored, it is not necessary to access the hard disk 3 one by one from the next time, and the character fonts can be displayed at high speed.

As a result, since the types of characters used in general documents are about 500 to 1000 in most cases, in most documents, the character font used in the document is stored in the cache memory. As compared with the case where all character fonts are loaded on the main storage device, they only occupy about 10% of the storage area, without accessing the font ROM and accessing the hard disk one by one. Without, high speed font display is possible.

In the present embodiment, the character code analysis unit 1b is provided, and the character code analysis unit 1b analyzes the character code string from the application execution unit 1a and decomposes the character code by character. However, when the application execution unit 1a outputs character codes one by one, it is not necessary to provide the character code analysis unit 1b.

[0033]

[Effect of the device]

 As described above, according to the present invention, a font cache area for storing a character font loaded from the hard disk into the main storage device and having a high sentence usage frequency, and a font table that associates the character code of the character font with the address. If a character code is output during execution of an application program, the character code is searched in the font table of the main storage device based on the character code, and if the character code exists, the character code is Since the corresponding character font is output, the hard disk is not accessed one by one, and the character font can be displayed at high speed without the need for a dedicated ROM.

Further, when there is no character code of the character font to be displayed in the font cache area of the main storage device, the present invention determines whether or not there is a space in the font cache area. While the character font corresponding to that character code is loaded from the hard disk to that space, if there is no space, the character font that was loaded first is discarded to create a space and the space that corresponds to that character code is written. Since the character font is loaded, the character font will be stored in the font cache area from the next time this character font is displayed, and the character font can be displayed at high speed.

[Brief description of drawings]

FIG. 1 is a configuration of a computer apparatus according to the present invention and C
The block diagram which shows the function of PU.

FIG. 2 is a flowchart showing a processing procedure of a CPU in this apparatus.

[Explanation of symbols]

 1 CPU 2 System ROM 3 Hard Disk 4 Main Storage Device 5 Display Memory 6 CRT 1a Application Execution Section 1b Character Code Analysis Section 1c Cache Search Section 1d Font Loading Section 1e Font Display Section 4a Program Storage Area 4b Font Cache Area

Claims (1)

[Claims for utility model registration] 1. A display device, a hard disk storing character fonts and application programs displayed on the display device, and characters displayed when the character fonts are displayed on the display device. In a computer device having a display memory for holding fonts, a font cache area for storing a frequently used character font loaded from the hard disk and a font table in which character codes and addresses of the character font are associated with each other. A main storage device provided, an application executing means for executing the application program to output a character code of a character font to be displayed on the display device, and a character code received from the application executing means. The above font table Cache search means for determining whether or not there is a character font corresponding to the character code, and when the cache search means determines that there is no character font corresponding to the character code, the font cache area If there is a space, the character font corresponding to the above character code is loaded from the hard disk to the available space, while if there is no space in the font cache area, the character loaded first If there is a font loader that discards the font to make a space and loads the character font corresponding to the above character code in that space, and if there is a character font corresponding to the above character code in the above font cache area, the above font table The character font is read based on the address of Computer apparatus characterized by comprising a font display means for output, the.