JPS58159578A - Display - 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 The present invention relates to a display device that displays characters, symbols, etc. on a screen such as a cathode ray tube (CRT).

More specifically, the present invention relates to a display device that simultaneously displays a plurality of screens composed of characters, symbols, etc. by dividing the display screen into several areas.

FIG. 1 is a block diagram showing an example of a conventional display device of this type. In the figure, 1 is a code memory that stores character information of multiple screens to be displayed as codes, and the data is sent from a controller (not shown) via bus 2. 3 is an address counter; This shows the display address on the CRT display monitor 4. 5 is an address converter which inputs the signal from the address counter 6, and converts the display address shown by the address counter 3 into
Address conversion information for converting the information to be displayed at that position into the corresponding address of the code memory 1 that stores the information is stored as a table. 6 generates a display pattern corresponding to the code read from the code memory 1;
This is a character generator for display on CRT 4. In a scanning line type (rusk scan type) CRT,
Display text as multiple scanlines. Therefore, the character
In order to display one line to the generator B, it is necessary to read the code information from the code memory 1 repeatedly for the code string forming the one line as many times as the number of scanning lines forming the character. A line start address counter 7 stores the contents of the address counter 6 at the top display position of each line during this repetition. At the end of scanning one scanning line, the value of row start at Vs counter 7 becomes address
The address counter 6 sequentially repeats and outputs the address value corresponding to that row. When scanning of the last scanning line constituting the row is completed, the value of the row start address counter 7 is updated to indicate the start address value of the next row based on the value of the address counter at that time.

FIG. 2 is an example of a display in the conventional device shown in FIG. 1, assuming that the display screen is 10 characters and 7 lines. This is a display example in which a screen portion 9, in which five characters and six lines of English characters are displayed, is divided and displayed in the lower right corner of a screen portion 8, in which kana characters are displayed. Here, 10 is the display start position of the screen portion 8, and 11 is the display start position of the screen portion 9.

FIG. 6 is a display example in which the display area of the screen portion 9 in the display example of FIG. 2 is enlarged by one character each vertically and horizontally.

FIG. 4 shows the contents of the code memory 1 when FIGS. 2 and 3 are displayed. Here, 12 is the code
Address 13 of memory 1 indicates its contents.

Figures 5 and 6 show the contents of the address conversion table for displaying the display examples in Figures 2 and 6, respectively, in a form that corresponds to the display screen, and each numerical value is indicated at its display position. The address value of code memory 1 corresponding to is shown.

As shown in FIGS. 5 and 6, when expanding the display area of the screen portion from FIG. 2 to FIG. 6, in FIG.
All the contents of the address translation table in the area 14 surrounded by the broken line must be changed, which requires a lot of processing time.

In this way, in the conventional device as shown in FIG.
Since the divided display of the screen was performed using an address conversion table, there was a drawback that a lot of processing time was required when changing the size of the divided area and scrolling.

The present invention eliminates such drawbacks in conventional devices, and
The purpose is to speed up processing such as changing the display screen area.

The device according to the present invention does not have an address conversion table in the screen division mechanism, but uses a map counter that operates in synchronization with the address counter and a map memory that only stores information on which plane to select. The feature is that it shows the address on the code memory.

FIG. 7 is a block diagram showing an embodiment of the present invention. In this figure, parts that perform the same functions as those in FIG. 1 are designated by the same reference numerals, and their explanations will be omitted. In Fig. 7, numeral 15 is a map memory that stores codes on the CRT 4.
Screen switching information indicating which screen on the memory 1 should be displayed is stored.

When the number of screen divisions is two, this information is represented by one bit for each display position, and is sent via bus 16 from a controller (not shown). 17.18 is the 1st. A second map counter indicates the display position of screen portions 8 and 9 on code memory 1, respectively;
According to the contents of 5, the count-up is performed in synchronization with the address counter 6 only when the count-up enable signal sent from the signal line 19 is on.
, 21 are first and second line start map counters that operate in response to the line start at Vs counter and store the start address of that line in each divided screen. 22.23 is
Code memory 1 in the first and second base registers.
Stores the display start address of each screen above. The information is sent from a controller (not shown) via bus 24.25. The output value of each base register 22, 23 is output from each line start map at the end of one display screen.
It is sent to counters 20 and 21 as an initial value. 26 is a selector which selects the first one based on the contents of the map memory 15;
．． The output of one of the second map counters 17, 18 is selected and its contents are sent to the code memory 1.

FIG. 8 is an explanatory diagram showing the contents of the map memory 15 for displaying the display example of FIG. 2 in a form corresponding to the display screen in the apparatus according to the present invention.

In the map memory 15, QQ(k is stored in the area where screen portion 8 is displayed, and 5s-ps is stored in the area where screen portion 9 is displayed. , the first and second base registers 22, 23,
0 (address in code memory 1 corresponding to display start position 10 of screen portion 8) and 100 (screen portion 9), respectively.
The address on the code memory 1 that corresponds to the display start position 11 is set.

Here, when changing the division of the display screen 517C as shown in FIG. 6, in the present invention, the portion indicated by 27 in FIG.
The content of the increased portion of the area that displays screen portion 9 is
This can be done simply by changing from Q%% to N1XX. Also, if you want to scroll within the screen split area without changing the size of the screen split display area, map memory 1
There is no need to change the contents of base register 5 (it can be done by simply changing the value of base register 2).

For example, if the screen portion 9 in FIG. 2 is to be scrolled one line upward, it is only necessary to change the contents of the base register 26 to 105.

Note that in the above explanation, the number of screen divisions is 2 to simplify the explanation, but this number of divisions is based on the map memory 1.
It is determined by the number of pits per display position in 5 and the number of map counters (line start map counter, number of base registers), and the number of map memory bits, number of map counters, etc. By increasing the number of screen divisions, you can easily increase the number of screen divisions. By the way,
When the number of divisions of the display screen is 8, the map memory is divided into 6 bits for each display position, map counter, and line start map.
The number of counters and base registers may be eight each.

Furthermore, in the above description, it is assumed that the invention is applied to a display device, but the technical idea of the present invention is not limited to this, but can also be applied to printers, etc. for fields that require layout editing of printed pages. can.

As explained above, according to the present invention, when changing the divided area on the screen and scrolling within the divided area, the map
Since it is only necessary to change the contents of the changed portion of the memory or the contents of each base register, this modification process is simplified and the processing time is advantageously shortened.

Further, since the circuit means for screen division processing has a simple configuration, it can be easily integrated into an LSI, and the overall hardware cost can be reduced.

[Brief explanation of drawings]

FIG. 1 is a configuration block diagram showing an example of a conventional display device.
FIG. 2 shows an example of divided display of the display screen in the device shown in FIG.
6 is a display example in which the display area of the screen portion 9 in FIG. 2 is enlarged, and FIG. 4 is a display example in which the display area of the screen portion 9 in FIG. 2 is enlarged. An explanatory diagram showing the contents of the code memory when displaying FIG. 6, FIGS. 5 and 6 are explanatory diagrams showing the contents of an address conversion table for displaying the display examples of FIGS. 2 and 3,
FIG. 7 is a configuration block diagram showing one embodiment of the present invention;
This figure is an explanatory diagram showing the contents of a map memory for displaying the display example of FIG. 2 in the apparatus of FIG. 7. 1- code memory, 3- address counter. 4- CRT, 5----address converter, 6-
Character generator, 7-line starting address counter. 15--1-Map memory, 17.18-Map memory
counter. 20, 21---One line start matsub counter, 22.
23 - base register, 26 - selector. Agent Shin Kuzuno - Figure 1 Figure 4 Figure 2 O 3rd ry! Figure 5 I○ Figure 7

Claims (1)

[Claims] (1) In a display device that displays multiple screens containing characters and symbols at the same time by dividing the display screen into a few areas, a map indicating the addresses in the code memory of the multiple screens to be displayed separately. a group of counters, a group of row start map counters that indicate the start address of each row, a group of base registers that give an initial value to this row start map counter, and a map counter that stores information on which map counter to select. A memory, a selector that selects the map counter based on the contents of the map memory, and an address counter that indicates a display address on a display screen, and the map stored at the address indicated by the address counter is provided.・Select the map counter to operate in synchronization with the address counter based on the contents of the memory,
A display device characterized in that the content of a selected map counter is sent to a code memory as an address on the code memory corresponding to its display position.