JPH02201635A - Multifont load system - Google Patents

Abstract

PURPOSE:To enable switching font data corresponding to each display device by selecting character font data to be needed in each display mode and loading them to a character generator. CONSTITUTION:A corresponding relation between the screen mode of each display and the size of the font data needed by the mode and a pointer to indicate the address of the character font data for each display are table-defined. A font loader 5 selects the font data needed by each display by an instruction from an operation system (OS) 1 or video controller 2 and loads the font data to the character generator on a display controller 3 to control each CRT monitor 4. Thus, the display can be executed in the same character code system to all displays, and even if the system in which two or more displays can be connected, the font data corresponding to each display is used by switching it.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a multi-font loading method used in a display system requiring font switching.

(Prior Art) Usually, one display device is connected to one computer system, and data is input and output. The fonts possessed by the display device are fixed and are either built into the display, or a character generator is constructed from RAM and transferred from the host as necessary. That is, character font data dedicated to that display was switched. Or, even if two or more display devices are connected, font data switching is only supported for the main display device, and only one font data is supported for the other display devices. It wasn't allowed.

(Problem to be Solved by the Invention) By the way, the character code used for each Tafune is different, and when the same system is supplied to each country, the font data is switched to correspond to the character code of the Tafune.
In systems to which the above-mentioned display devices can be connected, there have been problems such as the inability to completely switch fonts.

The present invention has been made in view of the above circumstances, and provides a multi-font loading method that can switch font data for each display device for a system that can connect two or more display devices. The purpose is to

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a display system that includes a plurality of character fonts and loads necessary character fonts into a character generator according to the display mode to obtain a desired display. Data is defined in advance in the pointer address table in which character font data is stored for each display mode, as well as the correspondence between the sizes of character font data required for each display mode, and each font is changed every time a font switching instruction is issued. This method is characterized in that the required character font data is selected in the display mode and the character font data is loaded into the character generator.

(Function) As described above, the present invention selects font data corresponding to each display device from font data held in memory and loads the data into each character generator. A table is defined that shows the correspondence between the screen mode of each display and the size of font data required by that mode, as well as a pointer indicating the address of the character font data for each display, and is executed every time a font switching command is issued. , select the font data required by each display, and load the font data into each character generator.

This allows all displays to be displayed using the same character code system.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, reference numeral 1 is an operating system (O3), which receives instructions from an operator and notifies the hardware. Code 2 is the video controller, O8]
Convert instructions from to hardware instructions.

Reference numeral 3 denotes a display controller, which is a commercially available LSI that controls a connected display. Reference numeral 4 is a CRT monitor that actually displays characters. Reference numeral 5 denotes a font loader, which has a function of transferring font data to the character generator RAM built in each display controller 3 in response to a command from the O8I or a command from the video controller 2.

FIG. 2 is a block chart showing the operation of the embodiment of the present invention in macro terms. In the figure, step (2) is a step for checking the screen mode, and the font size to be loaded on each display is determined according to this mode.

Step (2) is a step of extracting the font data address, and searches for the address of the font data required by each display. Step (2) is a step for creating command data, and a pig table required for passing fonts to each display controller 3 is created. Step (2) is a step of loading necessary fonts into the character generator, and font data is loaded into the display character generator based on the command table.

FIG. 3 is a diagram cited for explaining the operation of the embodiment of the present invention, and shows the data table structure prepared for each display. In the figure, 31 indicates the number of font data used by one character, 32 indicates the number of characters to be loaded into the character generator, and 33 indicates the start address of the font data to be loaded.

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

First, an interface for calling the font loader 5 is prepared in advance in the O3I and the video controller 2. The font loader 5 is started from the O81 when the character code is changed by the operator, or from the video controller 2 when the screen mode is changed, and the font loader 5 is started from the O81 when the character code is changed by the operator, or from the video controller 2 when the screen mode is changed. Load font data into the generator.

When the font loader 5 is activated, it checks the current screen mode to find out the font size required by each display. Once the font size is determined, the address where the font is actually stored is retrieved, and a data table as shown in FIG. 3 is created for each display device 4. Using this data table, font data is copied to the character generator of each display controller 3.

Although the present invention has been described by exemplifying a system configuration in which two or more displays are connected, the present invention is not limited to this, and even if only one display is connected, multiple font data can be transmitted. It can be similarly applied to systems used simultaneously.

[Effects of the Invention] As explained above, according to the present invention, it is possible to display the same character code system on all the connected displays, and therefore, a system is provided in which two or more displays can be connected. It is also possible to switch and use font data that corresponds to each display.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the invention, FIG. 2 is a flowchart showing the operation of the embodiment of the invention, and FIG. 3 is a diagram showing the structure of a data table used in the invention. 1... Operating system (O8), 2...
- Video controller, 3... Display controller, 4... CRT monitor, 5... Font loader. Applicant's representative Patent attorney Takehiko Suzue Operator font switching command Figure 1 Figure 2

Claims (1)

[Claims] In a display system that is equipped with multiple character fonts and obtains a desired display by loading the necessary character fonts into a character generator according to the display mode, the correspondence between the display mode and the size of character font data required for that display mode, and each Data is defined in advance in a pointer address table in which character font data is stored for each display mode, and each time a font switching instruction is issued, the character font data required for each display mode is selected, and the character font data is A multi-font loading method characterized by loading fonts into a character generator.