JPS6318213B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to a display control method for a Japanese language display device, and in particular to a method for changing attributes from alphanumeric attributes to Japanese attributes for display control areas on the screen, that is, items. This invention relates to a display control method for preventing meaningless erroneous characters from being displayed due to temporary mismatch between data and attributes when

Background of the Technology As illustrated in Figure 1, conventional Japanese display devices divide the screen into multiple areas, etc., and allow alphanumeric attributes or Japanese attributes to be specified for each area. It is composed of Setting of these screen areas and attributes in the Japanese display device is performed under the control of a known screen definition means and screen processing program on the host side. The data in each area is converted into a character pattern by the corresponding character generator according to the specified attributes and displayed on the CRT screen.

FIG. 2 schematically shows a typical configuration example of the above-mentioned conventional Japanese language display device. In the figure, 1 is a display control device; 2 is a display control device;
is a screen memory, 3 is an attribute table that stores attribute data based on the screen definition, 4 is a multiplexer that switches between the host side access address and the CRT side refresh address for the screen memory 2 and attribute table 3, and 5 is a Distribution for selectively supplying the screen data read from the screen memory 2 to each character generator depending on whether the attribute data in the corresponding attribute table 3 specifies alphanumeric or Japanese. Department. 6 is an Alpha Anonymous Character Generator (CG), 7 is a Japanese Character Generator (CG),
8 is an OR gate, 9 is a display circuit, and 10 is a CRT. The attribute table 3 is configured to display, for example, the start point and end point of a defined area and their attributes, or the attributes in correspondence with the screen memory 2 in blocks of a certain size.

Next, the operation of the device shown in Fig. 2 will be explained.
Control information, screen data, and attribute data sent from the host via control lines, address lines, and data lines are controlled by the display control device 1.
The multiplexer 4 is switched to the host side, and the data are written to the screen memory 2 and attribute table 3, respectively. The screen data written in the screen memory 2 is immediately read out by switching the multiplexer 4 to the refresh address side, and according to the attribute data in the attribute table 3, the screen data in the alpha anonymous attribute specification area is read out immediately after switching the multiplexer 4 to the refresh address side. The screen data of the Japanese attribute specification area is converted into a character pattern by the Meritsuku CG6 and the Japanese CG7, and then passed through the OR gate 8 and the display circuit 9.
Displayed on CRT10.

By the way, there are cases where it is necessary to change the specification of an area with either alphanumeric or Japanese data attributes to the other attribute due to processing requests or due to scroll operations, etc. be. At this time, updating the screen data takes time compared to rewriting the attribute specification, so the update timing of the screen data and attribute data is shifted, and the old screen data is temporarily distributed to the wrong character generator. For example, when alphanumeric data is converted into a character pattern using Japanese CG, a problem arises in which meaningless data is momentarily displayed on the CRT screen. .

FIG. 3 is an explanatory diagram thereof. Reference numeral 11 indicates an alpha anonymous attribute designation area on the CRT screen, and it is assumed that alpha anonymous data is displayed. 12 shows an example of meaningless data that appears temporarily by changing the attribute of area 11 to Japanese. Reference numeral 13 indicates the same area in which Japanese data was normally displayed thereafter.

OBJECT AND CONFIGURATION OF THE INVENTION In order to prevent meaningless data from being displayed on the screen when changing the data attributes described above, the present invention promptly deletes old data in the screen area that is subject to change at the same time as changing the data attributes. This is replaced with a null code to clear it, and nothing is displayed until data corresponding to the newly specified data attribute is written in this screen area, as shown at 14 in FIG. 3.

As a configuration for this purpose, the present invention includes a screen memory that stores display data corresponding to the screen, divides the screen, and assigns either an alphanumeric attribute or a Japanese attribute to each divided area. When displaying data by changing an area designated with either the alphanumeric attribute or the Japanese attribute to the other attribute on a Japanese display device that can specify the Once the screen memory area has been
After clearing by writing a null code,
It is characterized in that data of the other attribute is written in the area.

Embodiments of the Invention The present invention will be described below with reference to Examples.

FIG. 4 is a block diagram of a Japanese language display device according to an embodiment of the present invention. Since the apparatus of this embodiment is constructed based on the apparatus shown in FIG. 2, some common parts are omitted from illustration.

In FIG. 4, the display control device 1, screen memory 2, and attribute table 3 are the same as those in FIG. Further, 15 is a host computer, 16 is a screen processing unit, 17 is an input device such as a keyboard, 18 is a Japanese display device, 19
20 represents a data attribute change/clear processing section, 20 represents a null code generation section, 21 represents an OR gate, and 22 represents a multiplexer.

The host computer 15 uses a screen processing program in the screen processing unit 16 to analyze screen operation signals such as screen definitions or scroll instructions that include changes in data attributes that are given by the operator from the input device 17, and changes the attributes. The address specifying the screen area and the type data of the attribute to be changed are notified to the Japanese display device 18 as a data attribute change command.

In the Japanese display device 18, the attribute table 3 is updated based on the data attribute change command, and at the same time, the data attribute change clear processing unit 19 terminates the data attribute change command, and (a) displays the screen memory 2 to be cleared. (b) Null code generation and (b) clear address generation are controlled, and the Null code is written into the corresponding area of the screen memory 2.

The null code generation section 20 is controlled by the data attribute change clear processing section 19 to generate a null code. For example, "00" in hexadecimal notation is used as the null code. Null codes do not generate any character patterns in both the alphanumeric character generator and the Japanese character generator. Therefore, the Null code corresponding area on the CRT screen becomes a blank area.

The OR gate 21 couples the null code from the null code generator 20 or the data from the host to the data input terminal of the screen memory 2.

During clear processing, multiplexer 22 selects the clear address supplied from data attribute change clear processing section 19 and accesses screen memory 2. Clear addresses are generated successively in a known manner within a range of screen memory addresses within the area where data attribute changes are made.

The data attribute change clear processing unit 19 transmits data to the screen memory 2 mentioned above via the display control device 1.
for successively generated clear addresses of
Writes a null code, that is, executes clear processing.

As described above, all data attribute change areas in the screen memory 2 are filled with null codes.
As a result, when reading screen memory 2 and attribute table 3 in the next refresh cycle, the old screen data in the attribute change area has already been read.
Since the Null code is cleared by the Null code, the Null code is converted as a blank pattern in both the character generator and the character generator, regardless of the switching state of the distribution section 5 shown in FIG. It performs character pattern conversion to prevent meaningless data from being output.

After that, when data having the attribute is written in the attribute conversion area, a proper character generator is selected by the distribution section 5, so that normal character pattern conversion processing is performed during refresh reading.

In the configuration of the embodiment described above, the data attribute change clear processing unit 19 and the null code generation unit 20 are located in the Japanese display device, but all these functions are implemented by the screen processing unit of the host computer 15. It is also possible to include it in 16. In this case, it is necessary that the response time on the host side be short, but since the generation of the null code and the generation of the clear address are all executed by software in the screen processing section 16, the Japanese display device itself The configuration of
The configuration of the conventional device as shown in FIG. 2 can be left unchanged.

Effects of the Invention As described above, according to the present invention, by immediately clearing the screen area after changing the data attributes of the screen area, it is possible to prevent the temporary display of meaningless character data. , can provide a high quality display screen.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a display screen in which different data attributes are specified; FIG. 2 is a configuration diagram showing an example of a general Japanese display device; FIG. 3 is an explanatory diagram of a display screen of the present invention FIG. 4 is a configuration diagram of an embodiment of the present invention. In the figure, 1 is a display control device, 2 is a screen memory, 3 is an attribute table, 4 is a multiplexer,
5 is a distribution section, 6 is an alphanumeric character generator, 7 is a Japanese character generator, 8 is an OR gate, 9 is a display circuit, 10 is a
CRT, 15 is a host computer, 16 is a screen processing unit, 17 is an input device, 18 is a Japanese display device, 19 is a data attribute change/clear processing unit, 20 is a null code generation unit, 21 is an OR gate, 22 is a multiplexer shows.

Claims (1)

[Claims] 1 Japan is equipped with a screen memory that stores display data corresponding to each screen, and is also capable of dividing the screen and specifying either alphanumeric attributes or Japanese attributes for each divided area. When displaying data by changing an area designated with either the alphanumeric attribute or the Japanese attribute to the other attribute in a language display device, the area of the screen memory where the attribute was changed is temporarily nullified. A display control method characterized in that data of the other attribute is written in the area after the area is cleared by writing a code.