JPS63243991A - Graphic 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 [Object of the Invention] (Field of Industrial Application) The present invention relates to a character display method for a graphic display device that temporarily functions as a character display.

(Prior Art) FIG. 3 is a block diagram showing an example of a conventional graphic display device. When the position and color information of the drawing figure is given from the processor 1, the drawing controller (DD
A, BM, etc.) 2 generates dot pattern information of the drawn figure, and this is written into the frame memory 3.

The dot pattern information of the figure read out from the frame memory 3 is stored in the lookup table 4 for red (R) and green (G).
) and blue (B), and each color is input to the D/A converter 5. The D/A converter 5 converts the input digital information into an analog video signal and outputs this to a monitor 6 such as a CRT, on which graphics are displayed in color.

Such a graphic display device must temporarily serve as a character display for interaction with a host computer while displaying graphics. In order to display this character, the character was written one dot at a time in the figure frame memory 3, but this method had the disadvantage that when the character was erased, the displayed figure was also erased. . Therefore, in order to avoid this drawback, an increasing number of systems are creating a character brain dedicated to characters in the frame memory 3, but with this method, it is necessary to add a dedicated brain, and the character is displayed only in a single color. Such shortcomings were rare.

(Problems to be Solved by the Invention) When displaying characters on a conventional character display, there was a drawback that when the characters were erased, the figures were also erased. Further, in the case where a dedicated character plane is added in order to avoid this drawback, it is necessary to add an additional brain, and the characters are often displayed in a single color. SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks, and aims to provide a graphic display device that can display multiple colors without adding a dedicated brain and can erase only characters.

[Structure of the Invention] (Means for Solving the Problems) The present invention reads figures and character information written by a drawing controller from a frame memory composed of a plurality of brains, and reads them using a lookup table. In a graphic display device that displays the graphics and characters on a monitor by converting them into color information and then converting them into video signals of three primary colors using an A/D converter,
a holding means for holding character-dedicated brain designation information for setting an arbitrary brane in the frame memory as a character-dedicated plane; and a holding unit that stores character pattern information in the brain designated as the character-dedicated brain in the frame memory and graphic information in the remaining brains. a writing control means for writing; a selection means for selecting and outputting pattern information from a brain specified as a character-only plane in the frame memory by the holding means; A lookup table for a character to be converted is provided, and output data from the lookup table for the character is output to the monitor via the A/D converter.

(Function) In the graphic display device of the present invention, the write control means writes character information to the character-dedicated brain in the frame memory and graphic information to the remaining brains based on the character-dedicated brain designation information of the holding means.

The selection means selects display character information from the brain of the frame memory designated as the character-dedicated plane and outputs it to a dedicated look-up table. The video signal output means outputs 100% of the video signal of the color set from the A/D converter to the monitor based on the output data from the dedicated lookup table. As a result, multicolored characters are displayed on the display graphic on the monitor screen.

(Example) An example of the present invention will be described below with reference to the drawings, in which the same parts as those of the conventional example are denoted by the same reference numerals. FIG. 1 is a block diagram showing one embodiment of the graphic display device of the present invention. Reference numeral 1 denotes a control processor that provides drawing instructions for figures and characters, as well as related position, color information, character lane designation information, etc., and 2 a drawing controller that generates dot pattern information for drawn figures and characters based on the position information from the control processor 1. , 3 is a 12-plane frame memory in which dot pattern information of figures and characters is written, 4 is a lookup table that converts the dot pattern information of figures into R, G, B color information, and 5.6.7 is a look. D/A that converts the digital output of Uptable 4.10 into B, G, and R video signals.
Converter (for example, Am8151), 8 is a plane select register that holds information specifying the plane used exclusively for characters, 9 is a multiplexer that selects information from the character plane and outputs it to the lookup table 10, 10 is a character A lookup table converts dot pattern information into color information. In addition, D
/A converter 5.6.7 inputs signals to enable terminal EN and data terminal 0VDATA, display information from lookup table 4 is input to OV DATA regardless of whether it is input to DATA@child. Outputs B, G, and R video signals of display information. 11 is a processor bus.

Next, the operation of this embodiment will be explained. The control processor 1 provides the drawing controller 2 with position and color information of drawing figures and characters, and causes the plane select register 8 to hold character-specific plane designation information. For example, planes 10 and 1 of the frame memory 3, which are made up of O to 11 planes according to the character-specific brain designation information.
If 1 is designated as a character plane, there will be planes O~ for graphics. , planes O to 9 are referred to as system planes. Note that up to four consecutive arbitrary planes can be specified as character-only planes. For example, the drawing controller 2 creates dot pattern information of a figure as shown in FIG. 2(^) and writes it to the system plane, and also creates a character "" as shown in FIG. 2(B).
Dot pattern information for the character "1.2.3" is created and written on the character plane 1, and dot pattern information for the character "4.5.6" as shown in FIG. 2(C) is created and written on the character plane 2. write to. The graphic drawing information read from the system planes O to 9 of the frame memory 3 is input to the lookup table 4, where it is converted into R, G, and 8 color information, and then sent to the D/A converter 5.
6.7 is input to the Data terminal. D/A converter5.
6.7 is the digital signal input to the Data terminal.
, G, and R video signals and output them to a monitor (not shown). On the other hand, the character-only brain designation information held in the plane select register 8 is given to the multiplexer 9. As a result, the multiplexer 9 selects character information written in a plane used as a character-only plane (here, planes 10 and 11) from the frame memory 3, and outputs this to the lookup table 10. The lookup table 10 sets the enable terminal E of the D/A converter 5.6.7 according to the information from the plane 10.11 as shown in the following table.
N and an enable signal to the data terminal 0VDATA as display information, and the D/A converter 5.6.7 forcibly outputs the corresponding video signal.

(Left below) In addition, in D/A converter 5.6.7, terminal EN and terminal 0
When a 1" signal is input to the VDA terminal A, it outputs B, G, and R video signals corresponding to character data, regardless of whether a signal is input to the DATA terminal. As shown in Figure 2 (D), the system plane figure and character plane 1.2 character are combined and displayed.In this case, the system plane figure is white, and the character plane 1.2 character is white. designated as red and green.

According to this embodiment, up to four consecutive planes can be arbitrarily selected from among the planes constituting the frame memory 3 and used as character-dedicated planes, so there is no need to add character-dedicated planes. Furthermore, since it has a lookup table 10 that converts character data of a character-only plane into color information, characters can be displayed in multiple colors. Furthermore, since the characters are written on the character-dedicated plane, the displayed figures do not disappear when the characters are erased.

[Effects of the Invention] As described above, according to the graphic display device of the present invention, it is possible to perform multicolor display without adding a dedicated plane, and it is possible to erase only characters.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the graphic display device of the present invention, and FIG. 2 shows the graphics written in the system brain of the device shown in FIG. 1, the characters written in the character plane, and the monitor. FIG. 3 is a block diagram showing an example of a conventional graphic display device. 1... Control processor, 2... Drawing controller 3
...Frame memory. 4.10...Lookup table 5.6.7...D/A converter 8...Plane select register 9...Multiplexer agent Patent attorney Nori Chika Ken Shu Kanshu Sanno -

Claims (1)

[Claims] The graphics and character information written by the drawing controller is read from a frame memory composed of multiple planes, and after converting this into color information using a lookup table, an A/D converter converts it into a video signal of three primary colors. a graphic display device that displays the graphics and characters on a monitor by converting the figures and characters into a character-only plane; a writing control means for writing character pattern information to a plane specified by the plane and figure information to the remaining planes;
a selection means for selecting and outputting pattern information from a plane designated as a character-only plane in the frame memory by the holding means; and a character lookup for converting the character pattern information read from the character-only plane into color information. a table, and outputs output data from the character lookup table to the monitor via the A/D converter.