JPS6298390A - Display unit - 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 display device capable of controlling data for each pixel on a display screen.

[Background of the invention]

A block diagram illustrating a conventional color display device using cathode ray '1 (CRT) is shown in FIG. In FIG. 2, 1 is an arithmetic processing unit (CPU'), 2 is a read/write control circuit (write control circuit), 5 is a display control circuit, 4 is a CRT, 5°6.7 is a serializer, 8, 9.10 are red and green.

This is display memory for each blue pigment.

In this color display device, display data is written by the CPU 1 via the read/write control circuit 2 into display memories 8 and 910 prepared for each of red, green and blue pigments. The display memory 13.9.10 has a capacity corresponding to each pixel on the display screen, and information for each pixel is written therein. The display data written in the display memo IJ8, 9.10 is read by the display control circuit 5 in synchronization with the scanning of the CRTa, serialized by the serializer 5, 6.7, and sent to the CRTa. , green, and blue electron guns are driven to display a desired screen on the display screen.

In this conventional display device, when displaying a cursor that can be moved pixel by pixel, display memory 8I9110 is used.
This is done by writing the cursor display data to
At this time, in order to restore the original display data after moving the cursor, save the display data to a memory separate from display memory 3, 9.10 before writing the cursor data, write the cursor data, and save it after moving the cursor. The displayed data is restored to the display memory lJ8, 9.10.

However, with this conventional method, if the display data is overlaid on the cursor data, the display data will be destroyed after the cursor moves, and to avoid this, it is necessary to erase the cursor before writing the display data and move the cursor to the cursor position. After restoring the saved display data, it is necessary to write the display data to the display memo IJ8, 9.10, and then write it again to the display memory 8, 9.10, which is the cursor data. There is a problem that the time required for writing increases significantly.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a display device in which the processing speed is improved without increasing the time required to write display data by displaying a cursor that can be moved pixel by pixel.

[Summary of the invention]

In order to achieve the above object, the present invention provides a display device having a display memory (storage device) in which a plurality of bits are allocated as display data to each pixel on the display screen of the display device. ) for each pixel on the display screen, separate from the display memory.
By providing a memory for display control data to which bits or more are allocated, and a calculation circuit that calculates display tilt data for each pixel in the display data, displaying the cursor can be done by simply writing the cursor data to the memory for display control data. ,
This is a display device that allows display data to be written simply by writing it into the display memory regardless of the cursor.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. , D1 is a block diagram showing an embodiment of a display device according to the present invention. In Fig. 1, the same reference numerals indicate the same or similar parts throughout the drawings, and 1 indicates CP.
U, 2 is a read/write control circuit, 5 is a display control circuit, 4 is CR
, T (display device), 5, 6.7 is a serializer, 89.
10 are prepared for each pigment of red, green, and blue, and each contains multiple bits (5 bits) as color information corresponding to each pixel on the display screen.
This is a display memory (display device) that stores red, green, and blue data of display data to which bits are assigned. 11, according to the present invention, 1 bit (1
display i! that stores the cursor data (display control data) that cracked the bit (or more). 111 @Data memory,
12 is a serializer for display control data, 15, 14
, 15 are arithmetic circuits (OR arithmetic circuits) that calculate display control data for red, green, and blue display data, respectively.

Next, the operation of this embodiment will be explained. The CPU 1 writes red, green, and blue display data to be displayed as color information into the red, green, and blue display memories IJ8, 9, and 10 via the read/write control circuit (write control circuit) 2. The CPU 1 also stores cursor data (acceptance control data) into the display control data memory 11 via the read/write control circuit 2 independently of the display data. The display control circuit 5 displays memos in synchronization with the scanning of the C-T4! The contents of J8#9110 and the display control data memory 11 are read out, and the read data is serialized by the serializer 5+6*7+'2, and then converted into red, green,
The cursor data (display control data) is calculated (logical sum operation) on the blue display data and sent to CRTa, and the red display data is sent to CRTa.

Five green and blue electron guns are driven to display data on the display screen. At this time, cursor data (display control data)
is displayed as white, a mixture of red, green, and blue. To move the cursor here, the cursor on the display screen can be moved by moving the cursor data on the display control data memory 11, regardless of the contents of the display memories 8, 9, and 10.

As is clear from the above explanation, according to the present example 6, the cursor display (data display piece on the display side) is provided with a memory for display control data of 1 bit or more for each pixel of the display screen. Due to such reasons, the time required to write display data to display memory increases.

A cursor that can be moved pixel by pixel can be displayed without inviting the dog.

〔Effect of the invention〕

As described above, according to the present invention, since display data and display control data (cursor data) can be written independently of each other, a display device that can display a cursor that can be moved pixel by pixel without increasing the writing time of display data. I hope it can come true.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating an example of a display device according to the present invention, and FIG. 2 is a block diagram illustrating a conventional display device. DESCRIPTION OF SYMBOLS 1...CPU, 2...Reading spear control circuit, 5...Display control circuit, 4...CRT (display device), 5-7...
・Serializer, 8 to 10...Display memory (storage device), 11...Display control data memory (storage device)
12... Serializer, +5 to 15... Arithmetic circuit. 〆、−゛、

Claims (1)

[Claims] a display data storage device that stores display data to which multiple bits of color information are assigned corresponding to each pixel of the display screen, and a display control information that is separate from the color information and corresponds to each pixel of the display screen; a display control data storage device that stores display control data to which one or more bits are assigned; a display control circuit that reads and outputs display data and display control data from the display data storage device and the display control data storage device; A calculation circuit that calculates the display data and display control data output from the display control circuit and outputs the calculation results, and a display device that inputs the calculation results output from the calculation circuit and creates a display screen corresponding to the calculation results. A display device consisting of.