JPS6226470B2 - - Google Patents

Description

[Detailed description of the invention]

(Field of the Invention) The present invention relates to a CRT display device. (Prior art) In recent years, many display devices using cathode ray tubes (CRTs) have come into use, making it difficult for people and computers to
Communication between people and processes has also become easier. Furthermore, with the increase in the amount of information displayed on CRTs, many color display devices have come to be seen, which increase the variety of display data formats. This type of display device is effective in making complex displays easier to understand, by distinguishing displayed data by color, or by prompting the operator to operate using a flickering display, and is widely used. It is becoming more and more like this. In addition, when displaying information on this type of color display device, the data structure system in the display memory adopted in most conventional devices is as shown in Figure 2. It consists of two parts: the shape (shape) and the mode code part (color, frizz, etc.),
The display shape to be displayed on the CRT is specified by the display code section, and the color selection, presence or absence of flicker display, etc. are specified by the mode code section. Furthermore, like the display code section, the mode code section can be changed to red, for example, by combining signals of the required number of bits.
Green, blue, yellow, cyan, magenta, white and black 8 or more
It represents a type of color, and is coded by a combination of 3-bit signals corresponding to red R, green G, and blue B, as shown in Table 1, for example. However, if you want to use this type of display device as is and only change the aspect of the data displayed on the CRT screen, such as color scheme, presence or absence of flicker, etc. ,
All of the relevant display data stored in the display memory, that is, both the mode code and the display code, had to be changed, which was very inconvenient.

[Table] Therefore, if you want to easily change only the aspect (for example, color, presence or absence of flicker, etc.) of the data already displayed on the coded CRT screen without changing the display form, the third A display device having the configuration shown in the figure can be considered. This shows a display device having a total of eight color modes: black, red, green, blue, yellow, cyan, magenta, and white. In the figure, 1 is a mode change input device,
It is composed of a group of buttons for specifying the display mode, and the functions of each button are as shown in Table 2 below, for example.

[Table] In other words, 2 in FIG. 3 is an encoder circuit for converting the button signal from the mode change input device 1 into the mode code shown in FIG. It is as shown in . Further, 3 is a display memory, and a mode code section 4
The mode code section 4 and display code section 5, which are composed of

[Table] The input code is controlled to be written at each position specified by the display memory address signal 6. Now, in the above configuration, when any button of the mode change input device 1 is pressed, the encoder circuit 2 outputs the mode codes of R, G, and B according to Table 3, and the mode code of the display memory 3 is output. 4, which is then written to the location specified by display memory address 6. however,
At this time, the contents of the display code section 5 are controlled so as not to change. However, if the display data 7 (mode code + display code) is input from an input device such as a computer or a keyboard, it will be is input. That is, it is written to both of the two code sections. These codes written in the display memory 3 are sequentially read out at predetermined timings and sent to the character generator, where they are converted into video signals.
Displayed on CRT. As mentioned above, a method can be considered in which the display memory is divided into a display code section and a mode code section, and the memory of the mode code section can be easily changed using the mode change input device. A new drawback arises in that the display memory is divided and a control circuit is required for each divided memory, resulting in increased costs. (Object of the Invention) The present invention has been made in order to eliminate the above-mentioned conventional drawbacks and to change only the data of the display mode code section in the display memory, and it is possible to change the color of the display shape or the like with a simple operation. The object of the present invention is to provide a display device in which only the aspect state, such as the presence or absence of flicker display, can be changed. (Summary of the Invention) In order to achieve the above object, the present invention has the following configuration. That is, in the display device, a register is provided for temporarily storing display data designated by a desired address including the mode code data to be changed in the display memory, and the mode in this register is changed by the mode change input device. The configuration is such that after changing the data only in the code section, it is written again into the display memory specified by the address. (Examples) Hereinafter, the present invention will be described in detail based on illustrated examples. FIG. 1 shows a modified display mode of the present invention.
FIG. 1 is a configuration diagram showing an example of a CRT display device. This is an application of the present invention to the case where the aspect of display colors in a color display device is changed. In the figure, reference numeral 8 denotes a display memory, and a register 9 is inserted and connected between this and the encoder 2, and the mode change input device 1 is connected to the encoder in the same manner as in FIG. With the color display device configured in this way,
To change the display mode, follow the steps below. That is, when changing a part of the displayed screen to another color, the display device described above detects the position to be changed using, for example, a light pen, and inputs and specifies this address signal 6 into the display memory 8. By doing this, one piece of display data to be changed is stored in the register 9. This display data generally consists of two parts, the mode code section and the display code section, as shown in Figure 2.As mentioned above, only the mode code section is written with the code corresponding to the color you want to change. . The aspect code of the color desired to be changed can be obtained using the aspect change input device 1 and encoder 2 described above. As a result, the display data in register 9 will have the desired mode code, so if this is written again to the display memory specified by the original address, only the data in the mode code section of this display data will be changed. In other words, you can change only the color to the desired color while leaving the specified shape on the screen as it is. Therefore, this display device has a simple configuration and allows the color of the designated display section to be changed by a simple operation. In the above-described embodiment, a case was described in which the mode of display colors was changed, but it is obvious that the present invention is not limited to this and other modes such as the presence or absence of flicker display may be changed. (Effects of the Invention) As explained above, the present invention is extremely simple because display data including the mode code part to be changed is temporarily stored in a register, and only the part to be changed is rewritten in the register. This is effective in providing a display device that has a simple structure and allows the required portions to be changed with a simple operation.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of a display device according to the present invention, FIG. 2 is a configuration diagram of display data stored in a display memory, and FIG. 3 is a configuration diagram showing an example of a display device according to the present invention. FIG. 2 is a configuration diagram of a display device showing one possible method. DESCRIPTION OF SYMBOLS 1...Aspect change input device, 2...Encoder circuit, 6...Address signal, 8...Display memory, 9
……register.

Claims (1)

[Claims] 1. In a CRT display device that is controlled to display information in each of pre-divided and positioned sections on a raster scan type CRT screen, there is a display mode change input device and an external display memory. A register is provided, display data at a position to be changed specified by an external display memory address is first set in the register, and a mode code of the data set in the register by the display mode change input device is set. 1. A CRT display device having a display mode changing function, wherein the contents of the register are written again to the display memory location specified by the display memory address after only the contents of the register are changed.