JPH049317B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a so-called scroll-up or scrolling method in which character and numerical data read from a memory and displayed on a display device is shifted upward or downward to change one line of data to new data. The present invention relates to a display control device that displays down status.

This type of scrolling method on a CRT display includes a method of rewriting one line at a time starting from the top line of the screen, or a method of once erasing the entire screen and slowly rewriting the last line. With either method, there is no visual difference between scrolling up and scrolling down, so unless you read the data you can't tell whether it's up or down.

FIGS. 1A and 1B are front views of CRT screens showing scroll up and scroll down of the former method. Initially, for example, the first to fifth rows of data are displayed on screen 1, and when this is scrolled up, the first row at the top, as shown in the right diagram of Figure 1A,
The data in the row is rewritten to the data in the second row, and then the data is rewritten in the downward direction of the screen 1 in order from 2 to 3, 3 to 4, and 4 to 5. The rewriting of each line may be done slowly from the top one line at a time, or it may be done instantaneously at an invisible speed.

In the case of scrolling down, as shown in the right figure of Figure 1B, the first line at the top of the screen is rewritten to -1 line of data, and then 2→1, 3→2, 3
→2, 4→3, 5→4 are rewritten one line at a time from the top.

In the methods shown in FIGS. 1A and 1B, it is visually confirmed that the data has been rewritten, but unless the data is read, it is impossible to distinguish between scroll up and scroll down.

In view of the above-mentioned problems, the present invention makes it possible to determine at a glance whether scrolling up or down is being performed.

Embodiments of the present invention will be described below based on the drawings.

Fig. 2 is a block circuit diagram of a display control device showing an embodiment of the present invention, Fig. 3 is a front view of a CRT screen, Fig. 4 is a flowchart explaining the scroll down operation, and Fig. 5 is a flow chart explaining the scroll up operation. This is a flowchart explaining the operation. Further, FIG. 6 is a front view of the CRT screen showing the scroll down operation, and FIG. 7 is a front view of the CRT screen showing the scroll up operation.

In FIG. 2, the central processing unit CPU2 includes:
A memory 3, a keyboard 4 and a CRT 5 are coupled via interfaces 6, 7 and an address/data bus 8, respectively. Connected to the bus 8 via an interface 9 are printers and VTRs (not shown) that are controlled by this system.
The input to the gearboard 4 is processed by the CPU 2 and stored in the memory 3. The contents of the memory 3 are displayed on the screen 1 of the CRT 5 shown in FIG.

Screen 1 displays Y lines of data in the vertical direction and X characters (digits) in the horizontal direction, and the memory 3 has a storage area for display corresponding to X×Y outside of the data storage area. ing.

When scrolling down the displayed data, as shown in Fig. 6, for example, for the screen displayed across the 1st to 5th lines (Fig. 6a), scroll down as shown in Fig. 6b. First, the first line is rewritten with the data of the upper line (-1 line) that is not displayed. Next, as shown in FIG. 6c, the second row is rewritten with the data of the row above it (first row). Furthermore, as shown in FIG. 6d, the third row is rewritten with the data of the second row. In this way, a new screen is finally formed in which the display contents are shifted downward by one line, as shown in FIG. 6f.

Visually, each line is rewritten from top to bottom, so it can be clearly seen that scrolling down is being performed. Note that each line may be rewritten from left to right at a visible speed.

Similarly, when scrolling up, the 5th line, which is the bottom line of the screen in Figure 7a, is rewritten to the data in the lower line (6th line), which is not displayed, as shown in Figure 7b. Next, as shown in FIG. 7c, the fourth line is rewritten with the data of the fifth line. By repeating this in order, a new screen with the display contents shifted upward by one line is finally formed as shown in FIG. 7f. Since each line is rewritten from bottom to top, you can clearly see that scrolling up is occurring.

The above-mentioned scroll up and scroll down processes will be explained with reference to FIGS. 4 and 5.
First, in step S1 of FIG. 4, the first screen is displayed (FIG. 6a or FIG. 7a). Next, in steps S2 and S3, a determination is made as to whether the instruction is to scroll up or down from the keyboard 4, and if it is down, step S4 is performed.
Register A of CPU2 is set to Y+1.
Next, in step S5, register B is set to X. These registers A and B are provided to control the address for reading data displayed on the screen from the memory 3.

At the end of step S1, the CPU 2 holds as a read address the address of the data in the first digit E of the line next to the last line in FIG. 6a (the sixth line outside the screen). Therefore, steps S1 to S10
In the loop, return the read address by X digits x (Y+1) lines, and return the address of the first S in the line above the top line (first line) of the screen in Figure 6a (the (-1)th line outside the screen). Set. That is, the process of [address-1] and the operation in step S6 are repeated X times×(Y+1) times.

Next, in step S11, the cursor position on the CRT is set to Y = Set X.
Then, in steps S14 to S18, the data in the (-1)th row read from the memory 3 is transferred to the sixth row.
It is displayed on the top line of screen 1 as shown in Figure b. That is, one character is displayed in step S14, the memory address is advanced by one in steps 15 and 16, and the CRT display address (cursor) is advanced by one, and this operation is repeated X times.

The above one line display operation is performed in step S19.
The loop from S20 to S13 is repeated A=Y times,
Each row of data is sequentially displayed as shown in FIG. 6c, d, and e for each loop. Eventually the 6th
The data scrolled down by one line is displayed on the screen as shown in Figure f.

In the case of scroll up, the process jumps from step S2 in FIG. 4 to step S21 in FIG.
CRT display address (cursor position) is X=0,
Y=set to the last row. The read address of memory 3 immediately before scrolling is the line next to the last line (fifth line) in Figure 7a (first digit E of the sixth line outside the screen)
is set to . Therefore, steps S22 to S
28 (same as S12 to S18 in FIG. 4), the data on the sixth line is displayed on the last line of screen 1 as shown in FIG. 7b.

Next, through steps S29 and S30, one line is subtracted from the A register holding the number of display digits.
When the last line has been displayed, the read address is set to the first digit E of the seventh line as shown in FIG. 7b, so the next steps S31 to S37 are performed.
Then, the read address is returned to the first digit of the fifth row two rows up. That is, 2 is set in register C, and the read address is subtracted by X digits x 2 rows until C=0.

Next, in step S38, the CRT display address is set to X=0 and Y=previously displayed line minus 1, and the process returns to the loop of steps S23 to S28 to display the data on the 5th line as shown in FIG. 7c. Is displayed.
Furthermore, the loop of steps S23 to S38 is repeated until A=0, and each digit is sequentially rewritten upward as shown in FIG. 7d, e, and f. If A=0 in step S30, the scroll-up operation is completed and the processing program is returned to its original state.

Although the present invention has been described above with reference to preferred embodiments, various modifications can be made based on the technical idea of the present invention. For example, the screen may be scrolled horizontally, and vertically, for example, by two scrolls.
You may also scroll up or down line by line.

The display control device of the present invention changes the read address for reading data from memory so that each display line can display desired information across a plurality of display lines on the display. In a display control device that scrolls data in the vertical direction according to instruction information for the scrolling direction, when the instruction information instructs scroll up, the display is displayed on the lowest display line on the display. The data in the display line corresponding to the display line below it is changed and displayed sequentially from the left edge of the display line to the right edge, and then displayed in the display line one line above the bottom display line. The displayed data is changed to the data that was displayed in the bottom display line before the above instruction information was supplied, starting from the left end of the display line and moving to the right end, and then in the same way, the data displayed in the bottom display line is changed to the data displayed in the bottom display line. Scroll up by changing the data to be displayed, and when the above instruction information instructs to scroll down, the data displayed in the display line at the top of the display can be scrolled up by changing the data to be displayed. The data in the display line corresponding to the display line is changed and displayed sequentially from the left edge of the display line to the right edge, and then the data displayed in the display line one line below the topmost display line is changed and displayed as instructed above. The data that was displayed on the topmost display line before the information was supplied is changed and displayed from the left edge of the display line to the right edge, and then in the same way, the displayed data is changed sequentially to the bottom display line. This allows scrolling down.

Therefore, according to the present invention, when scrolling up, the display is changed sequentially starting from the lowest display line,
When scrolling down, the display is changed sequentially starting from the topmost display line, so it has the effect that it is possible to distinguish between scrolling up and scrolling down at a glance.

Furthermore, according to the present invention, in each display, the display is changed in order from the left end. Therefore,
Since the normal display is such that reading starts from the left end, it is easy to determine what the newly displayed data being scrolled means.

[Brief explanation of drawings]

1A and 1B are front views of a CRT screen showing conventional scroll up and scroll down display methods, respectively; FIG. 2 is a block circuit diagram of a display device showing an embodiment of the present invention; and FIG. 3 is a CRT screen.
A front view of the screen, FIG. 4 is a flow chart explaining the scroll down operation, FIG. 5 is a flow chart explaining the scroll up operation, and FIG. 6 is a front view of the CRT screen showing the scroll down operation. Figure 7 shows the scroll up operation.
FIG. 3 is a front view of a CRT screen. The symbols used in the drawings are: 1...CRT screen, 2...CPU, 3...memory, 4...keyboard, 5...CRT.

Claims (1)

[Claims] 1. Data displayed across multiple display lines on a display so that each display line represents desired information by changing the read address for reading data from memory. In a display control device that scrolls up and down in accordance with instruction information for the direction of scrolling, when the instruction information instructs scroll up, the display is displayed on the lowest display line on the display. The data is changed and displayed sequentially from the left edge of the display line to the right edge of the display line corresponding to the display line below it, and then displayed in the display line one line above the bottom display line. The data that was displayed in the bottom display line before the above instruction information was supplied is changed and displayed from the left end of the display line to the right end, and then in the same way sequentially up to the bottom display line. , scroll up by changing the data to be displayed, and when the above instruction information instructs to scroll down, change the data displayed in the display line at the top of the display to the display line above it. The data in the display line corresponding to is changed and displayed sequentially from the left end of the display line to the right end, and after this, the data displayed in the display line one line below the topmost display line is changed and displayed with the above instruction information. To change and display the data that was displayed on the top display line above before being supplied, starting from the left end of the display line and sequentially moving to the right end, and then in the same way, changing the displayed data sequentially up to the bottom display line. A display control device that allows scrolling down.