JPS59140487A - Inversion display controller - 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] [Technical Field of the Invention] The present invention relates to display control in a device that displays characters and figures, such as a character display device used as an input/output device of a computer, and in particular, In order to make it possible to arbitrarily set multi-gradation video information for reversed display, a color tone expansion memory for reversed attributes is provided, and the correspondence between the color tones before and after reversal is determined by the correspondence between the foreground color tone and the back brand color tone. The present invention relates to a display control device capable of performing multi-color, multi-gradation inverted display without being fixed to the display.

[Prior art]

Conventionally, in a CRT control device that performs multi-color, multi-gradation display, video information for one dot on the screen is allocated to several bits of display memory, and the output is input to a color tone expansion memory called a palette. When performing tone display, in the case of inverted display, the contents of the pit display memory corresponding to the IJ butte effective area are combined with the tone information corresponding to the foreground and the tone information corresponding to the pack ground in the area. The method for reversing the image was to rewrite the image and re-enter the output into the color tone expansion memory.

In this method, the pit display memory must be rewritten each time the inversion attribute is executed, which is inefficient, and the correspondence between the video information before inversion and the video information after inversion is limited to the foreground video information and the background video information. The problem is that it matches the correspondence with the video information and is fixed.

[Summary of the invention]

The present invention has been made to solve these drawbacks, and includes a rewritable random access memory in parallel with a normal color tone expansion memory on the output side of the bit display memory, and a color tone expansion dedicated to inversion attributes. By providing a memory and setting its contents at any time and arbitrarily,
A display that can perform multi-color, multi-gradation inverted display without rewriting the bit display memory and without fixing the correspondence between the pre-inversion and post-inversion tones to the foreground and background tones. The purpose of this invention is to provide a control device.

[Embodiments of the invention]

Hereinafter, the present invention will be explained with reference to the drawings.

1 to 6 show an embodiment of the present invention.

In FIG. 1, color tone information for one dot on the screen is stored as four-pit information at the same address point in each of bit display memories 0(1) to 6(4). When these 4 bits are output during screen refresh, the color tone expansion memory A (5) and color tone expansion memo! Sent to JB (6). Next, if this display information is data within the inversion attribute valid area, the output of the color tone expansion memo IJB (for inversion) (6) is selected by the inversion signal and sent to the monitor as the final video signal. .

The output 4 bits of the bit display memory are the addresses of the respective expansion memories, and the mechanism is such that each expansion element of one entry out of 16 entries is selected. In addition,
(7) is a multiplexer which enables only the output of one expansion memory by an inverted signal.

Next, referring to FIG. 2, each entry in the extended memory will be explained. The IJ numbers of extended memory A (5) and extended memory B (6) correspond to each other, and each has a non-inverted and inverted correspondence relationship. Assuming that entry 1 is selected by the 4-bit output of the bit display memory, if it is the inversion valid period, the blue B of the extended memory IJA (5)
Extended memory B in place of LUE (6) + 7) Hidden N
ON DISPLAY Video is displayed. The correspondence between each entry in memory A (5) and memory B (6) can be set arbitrarily, and is not affected by the correspondence between the foreground color and the background color before inverted display. Figure 3 shows this situation. Before inversion, the foreground was red RED and the background was blue BLUE, but by specifying the inversion attribute, red RED and blue BLUE are not swapped,
The color tone changes solely based on the correspondence between the entries set in extended memory A (5) and extended memory B (6). In other words, the foreground is sky blue 5 KYBi, UE, hack cry Y color hidden NO
N DISPLAY.

Although the above description has been made by taking as an example the case of a color tone expansion memory for color inversion, gray scale inversion color tone control may also be performed for a monochrome monitor.

〔Effect of the invention〕

As described above, according to the present invention, in addition to the non-inverting color tone expansion memory on the output side of the bit display memory, a) a color tone expansion memory dedicated to IJ buttes is configured as a random access memory. This has the advantage that non-inverted display and inverted display can be easily realized with arbitrary correspondence without rewriting the bit display memory.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining color tone expansion memo IJ A and B shown in FIG. 2, and FIG. 6 is a non-inverted and inverted display. This is an explanatory diagram showing. In the figure, (1) to (4) are pit display memo IJ, (5)
(6) is a color tone expansion memo for non-reversal U A, and (6) is a color tone expansion memo IJB for reversal. (7) is a multiplexer.・In addition, the same reference numerals in the figures indicate gaps or corresponding parts, respectively. Agent Shin Kuzuno −

Claims (1)

[Claims] When displaying characters or figures, the display information for one dot is stored in multiple pit display memories, and the output is passed through the color tone expansion memory. Equipped with dedicated color tone expansion memory using random access memory that can be rewritten independently for inverted display and inverted display, and can be used by switching between non-inverted and inverted color tone expansion memories. A reverse display control device characterized by: