JPS61103195A - Frame memory writing control system - 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 [Field of Application of the Invention] The present invention relates to a frame memory write control method suitable for storing a plurality of images in a frame memory in a graphic or image display device.

[Background of the invention]

The information stored in the frame memory of the conventional device is described in the literature ``Graphic processing engineering using computer display,''
As stated in June 1981, PP, 37,
Either the luminance component values of the three primary colors KGB or the table search address value of the color map table that holds the luminance values of KGB (
index).

The configuration of the above device is as shown in FIGS. 1 and 2. In either case, data in the command format of figures and images is stored in the storage device 11.21. The information written to the frame memory 13 23 that stores the display image is usually given as color attribute data in the figure or image data, but the bit configuration of the color attribute data is different from the storage in the two types of frame memories. It usually varies depending on the method. Graphics processor 12.22.

Frame memory 13. Interprets graphics and image commands.
A pixel to be stored in 23 is generated. That is, it generates frame memory write data (hereinafter referred to as pattern), write address, and write enable signal. In the case of FIG. 1, RGB brightness is transferred to the write pattern register 16. The write pattern register 26 in FIG.
The index corresponding to the search address of the color map table 29 is transferred.

In the case of FIG. 1, the contents of the frame memory 13 are directly stored in the D/
The signal enters the A converter 14, is converted into a KGB analog signal, and is displayed on the CRT monitor 15.

In the case of FIG. 2, the signal is converted into a KGB signal through a color map table 29 and a D/A converter 24, and then displayed on a CRT monitor 25.

By the way, when the number of planes in the frame memory increases due to the increase in capacity of the frame memory (increase in the number of bits per pixel), multiple images can be stored in the frame memory and displayed sequentially by using divided planes. Sometimes. At this time, the correspondence between the color attribute data and the frame memory write pattern needs to be controlled differently depending on whether the RGB luminance components are stored or the address of the color map table is stored.

Conventional display devices are difficult to use because the types of information stored in the frame memory and the correspondence between color tropism data and frame memory write patterns are fixed as shown in Figures 1 and 2. There were drawbacks.

[Purpose of the invention]

An object of the present invention is to store multiple images in a frame memory without changing the color attributes of figures or images.
An object of the present invention is to provide a method for controlling write patterns of a frame memory.

[Summary of the invention]

In the present invention, the information stored in the frame memory is RGB luminance or the address (index) of the color map table.
The color representation mode that indicates the frame memory, and the write plane selection data that selects the frame memory write plane,
Retrieving color attribute data (changing bits to create a predetermined frame memory write pattern, i.e. KG
In the case of B brightness expression, the color quality data is expressed with 8 bits each for RGB, and the upper bits of each of the 8 bits corresponding to the number of writing plane selection bits are extracted. In the case of index expression, the lower bits of the color continuity data corresponding to the number of writing selection bits are taken out and used as the writing pattern of the frame memory. This facilitates control when dividing the frame memory to store multiple images.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 3 to 6.

FIG. 3 is an overall configuration diagram of a display device that implements the method of the present invention. 31 is a storage device for storing graphics and image data in command format; 32 is a graphics processor that interprets the above commands and generates display pixels; and 33 is a frame memory that stores display pixels and corresponds to the display resolution of the monitor. 1024 x 1024 pixels can be stored as 24-bit information for each pixel.

When storing the luminance of the three primary colors RGB, each can be stored with 8-bit precision and is divided into three blocks. 34 is a color map table.

It defines the KGB ratio corresponding to the contents of the frame memory 33, and consists of three tables corresponding to the blocks of the frame memory 33.

Each table consists of 8 bits x 256 bits.

35, a D/A converter 36 for converting into RGB analog signals is in a color expression mode.

37 is a register for setting a frame memory write pattern; 38 is a circuit for selecting a frame memory read plane; 39 is a write address signal; 40.41
is newly added in the present invention, and 40 is a color expression mode register that stores the type of information to be stored in the frame memory, and has a 1-bit configuration. 41 is a circuit for selecting a write plane of the frame memory. The details are shown in FIG.

In FIG. 4, 42 is a write plane selection register, which is a 10-bit register.

42 is a block selection unit 43 of the frame memory.

It consists of a plane selection section 44. In this embodiment, each block of the frame memory 33 accesses a common plane number, but if the register 42 has a 24-bit format, it is also possible to divide each block into planes independently. . The contents of register 42 are set by graphics processor 32. 45 is AN
The write enable signal WE generated by the processor 32 using 24 D gates is controlled by the contents of the register 42.

The writing plane of the frame memory 33 is selected by the selection circuit 41 as a whole.

Next, FIGS. 5 and 6 show the procedure for creating a frame memory write pattern.

FIG. 5 shows that the contents of the color expression mode register 40 are '1'.
'', that is, in the case of RGB luminance. It is assumed that the contents of the write pattern selection register 42 specify plain writing of the lower half of each block. The contents of the register 50 in the processor 12 are expressed in 24 bits. When the data is color attribute data and KGB brightness is described from the lower byte, the graphics processor 32 refers to the contents of registers 42 and 40, extracts the upper 4 bits of each byte of register 5o, and determines the writing pattern. The broken lines in the figure indicate data relationships, and the solid lines indicate data movement.As a result, the RGB brightness is reduced to 16 gradations (24 bits), but graphic and image data It becomes possible to maintain one color tone without changing the color attribute data mixed therein.

FIG. 6 shows a case where the color expression mode is index and the contents of register 40 are ##Oyl.

It is assumed that the contents of the write plane selection register 42 are the same as in FIG. Register 60 of graphics processor 32
The contents are color attribute data in which a color index corresponding to each block of the frame memory is described.

At this time, the graphic processor 32 registers the register 4.
Referring to the contents of 2 and 40, four bits each corresponding to the number of plane selection bits of 44 are extracted from the lower bits of the register 60 and written to the write pattern register 37. As described above, even if the writing plane of the register 42 is arbitrarily changed, display pixels can be stored in a predetermined frame memory without changing the color attribute data.

According to this embodiment, in any color expression mode, information on a predetermined image can be stored in one selected frame memory plane without changing the color flexibility data, so that multiple images can be stored in the frame memory, Changes are dynamic.

〔Effect of the invention〕

According to the invention, RGBj! For two color expression modes: 11 degree and color map table address (index), frame memory write pattern creation when storing multiple images in frame memory is difficult to handle when color attribute data mixed in figure/image commands is created. Since this can be done without any changes, it is easier to control the display of the display device, and the process of changing color attributes can be omitted.
This has the effect of improving efficiency.

[Brief explanation of drawings]

1 and 2 are configuration diagrams of a conventional display device, FIG. 3 is an overall configuration diagram of an example of a display device according to the present invention, and FIG. 4 is a specific diagram of the frame memory plane selection circuit 41 shown in FIG. 3. The circuit diagrams illustrating an example of the configuration, FIGS. 5 and 6, are diagrams relating to each register at the time of creating a frame memory write pattern. 11.21.32...Storage device, 12,22.32.
・Graphic processor, 13, 23, 33...
Frame memory, 29.34... Color map table, 14, 24, 35... D/A converter, 15.
25.36...CRT monitor, 16,26°37...
・Frame memory write pattern register, 40...
Color expression mode register, 41... Play 1 Figure γ Figure 2

Claims (1)

[Claims] In a display device having a plurality of frame memories storing pixels corresponding to the display resolution of a display screen,
By inputting a certain form of color attribute data expressed as red, green, and blue luminance component data or color index data and frame memory write plane selection data, the color attributes are written according to the specification of the write plane selection data. A frame memory write control method characterized by extracting predetermined bits of data and creating data to be written to a frame memory.