JPS60159785A - Display decoration 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 [Technical Field of the Invention] The present invention relates to a display modification control method suitable for use in a display system equipped with a bitmap memory.

[Technical background of the invention and its problems]

CRT continues to develop as a man-machine interface
Recently, advanced functions have been required for displays. In addition to display modification control such as flashing (zolink), inversion (reverse), and high brightness display (high brightness), which are essential for displaying information, it also provides multicolor display, kanji display, full graphic display, etc. is a typical example.

A display system equipped with the above functions uses a processor (CPU)
) side has a memory for storing display codes and their display attributes, and a character generator converts the data into arm turn data and develops it on a bitmap memory.
It's on. A display controller reads and displays the data developed on this bitmap memory.

In addition to the display dot pattern, the above bitmap memory also has a 1-bit buffer memory allocated for each column/line.For example, when a surface of 80 columns x 2 columns and 25 lines is configured. , it is necessary to prepare a 2000-bit method.

This memory specifies the display state of the corresponding character (for example, whether it is displayed in reverse or not) using '1' and '0'. This means that when an attribute change instruction is given for a character in a column/line specified by a CPU command, it is difficult to judge whether or not the attribute is displayed from the dot pattern developed in the 9th turn of the display. It is necessary because there is no such thing. That is, it is necessary to check the contents of this buffer memory each time an attribute change instruction is issued, which is one of the causes of a decrease in the speed of display attribute processing.

If this buffer memory does not exist, there will be a problem where the display returns to normal display when an attribute change instruction is received while reverse display is already in progress.
It was an essential component in this type of display system.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and eliminates the need for the buffer memory and speeds up display attribute processing by allocating specific parts of individually allocated areas of display patterns for attribute display. The purpose of this invention is to provide an improved display modification control method.

[Summary of the invention]

In order to achieve the above object, the present invention defines a specific bit position of gloss turn data developed on a bitmap memory as an area indicating the display attribute of the pattern data, and
recognizes the display attribute by checking this position information, and when a display attribute change command arrives,
The configuration is such that execution of the attribute change process is prohibited.

This eliminates the need for a buffer located near the bitmap memory for specifying attributes, and improves the speed of display processing.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1g1 is a block diagram showing an embodiment of a display system in which the present invention is implemented. In the figure, 11 is a CPU;
2 is the main memory (MM), 13 is the display controller (CR)
TC), and each of the above modules is connected via an address data bus 19. A display memory DM (bitmap memory) 14 stores display data in the form of a bitmap image. 15 is an address multiplexer (MUX). The address multizolexer 15 is supplied with address information from the CPUJJ via the address/data bus 19 and address information from the display controller 13, and one of the address information is selected based on the display timing signal. Display memory 14
supplied to 16 is a shift register that converts the parallel pattern data obtained from the display memory 14 into serial dot data, and 17 is a video driver that supplies a video signal to a display unit (not shown).

18 is a character generator ROM that converts character codes into character gloss turn data.

In the above system configuration, display control is performed as shown below. That is, a buffer for display codes and display attributes is allocated to a part of the main memory 12, and display codes are successively output for each column/line.
1B, it is converted into character pattern data and expanded into the display memory 14. The data developed in the display memory 14 is displayed in a desired format via a shift register 16 and a video driver 17.

The display code and attribute information are stored in the main memory 12 in a combination of attribute information at address n and display code at address n+1, as shown in FIG. As attribute information, overline "'00100111", reparse "010000"
10'' is illustrated. FIG. 2 shows the correspondence between the display data allocated to the main memory 12 and the display screen.

FIG. 3 shows examples of the displayed numbers and turns that are displayed by implementing the present invention. In the figure, the alphabet "H" and the number '0', which are the display numbers and turns of the 8×8 dot matrix, are illustrated, and the set shown on the left is normal display, and the set shown on the right is reverse display. An example is shown. In the embodiment of the present invention, the attribute information setting area is not limited to the alphanumeric characters "H" and "o" shown in the figure, but one dot (marked 0 in the figure) at the upper right corner of all character patterns. Defined. Therefore,
The software includes an attribute processing program that checks the bits in the setting area and adjusts the display state, and a program that prohibits the execution of attribute change processing when the specified attribute display has already been executed. memory 1
It is stored in 2.

Whether or not reverse display is being performed can be easily determined by following the program stored in the main memory 12 and checking the dot at the upper right corner of the character pattern using the CPU II. Therefore, when a reverse command is issued from the CPU II in a state where reverse display is already being executed, a problem such as returning to normal display does not occur. That is, if the dot display at the upper right corner is changed to 61'', it can be recognized that reverse display is being performed, so this problem can be solved without using reverse bits prepared for each character.

Note that the embodiments of the present invention have been explained by illustrating only alphanumeric characters.
Even when displaying kanji characters, the same effect can be obtained by leaving a specific dot blank for attribute display and setting attribute information in this area.

〔Effect of the invention〕

As described above, according to the present invention, there is no need for a display attribute buffer prepared near the bitmag memory, so that the occupied memory area can be reduced and the display attribute processing speed can be improved.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of a display system in which the present invention is implemented, Fig. 2 is a diagram showing the correspondence between display data allocated to the main memory and the display screen, and Fig. 3 is a block diagram showing an embodiment of the display system in which the present invention is implemented. The following is an example of the display characters displayed when the 11... CPU, 12... Main memory, 13... Display controller, 14... Display memory (bitmap memory), 15... Address multiplexer, 16...
...Shift register, 17...Video driver, 18
...Character generator, 19...Address
data bus. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 No full reproduction

Claims (1)

[Claims] In a display system equipped with a bitmap memory that obtains display data from a memory in which character codes and their display attributes are stored, converts the data into character pattern data using a character generator, and displays the expanded data as a bitmap image, A specific bit position of the character or turn data developed in the bitmap memory is defined as an area indicating the display attribute of that display pattern, and by checking this position information, the display attribute is recognized and the specified bit position is A display modification control method characterized in that when an attribute display has already been executed, execution of an attribute change process is prohibited.