JPS60121495A - Scroll switching 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> The present invention relates to a display method in a personal computer or the like equipped with a CRT display device that displays display data by scanning a plurality of lines, and in particular to a smooth scroll display and a line scroll display. This relates to the switching method.

<Prior art> In the via map display system, there are two methods for scrolling the screen: line scrolling and smooth scrolling.
There are two ways.

Normally, terminal devices, personal computers, etc. employ either a line scroll method or a smooth scroll method. Furthermore, even if there is a device that can use both scrolling methods, switching between scrolls is done by inputting a certain command, and it is not possible to immediately switch to another scroll and display it while scrolling.

On the other hand, smooth scrolling slows down the display speed due to visibility control, and line scrolling has the problem that although the display speed is fast, the displayed content is difficult to see. Therefore, when only one of the scrolling methods is used, Even if both scrolling methods can be used, it is meaningless unless it is possible to immediately switch to another scrolling method during scrolling.

<Purpose> Therefore, an object of the present invention is to provide a scroll switching method that can immediately switch to another scroll and display it even in the middle of scrolling by operating a scroll switching key.

<Example> The present invention will be explained in detail below based on the drawings.

FIG. 1 is a block circuit diagram of a personal computer employing the system of the present invention.

In the figure, 1 is a central processing unit (CPU) that controls the display, 2 is a video RAM (VRAM) that stores actual display data, 3 is a display address generation circuit that generates display addresses for the VRAM, and 4 is a CRT, etc. a display device, 5 a memory for storing discontinuous points of display addresses;
6 is a memory that stores the number of rasters from the discontinuous point of the display address, 7 is a counter that subtracts the number of rasters by 1, 8 is a counter that increases the display address by 1, and 9 is for displaying VRAM data. The serial/parallel conversion circuit 10 is a keyboard equipped with a key S for switching to smooth scrolling and a key L for switching to line scrolling.

The address relationship between VRAM2 and display device 4 is shown in Figures 2 and 3.
As shown in the figure. For example, in a 640 dot x 400 raster CRT display device, address 0000 is located at the upper left of the display screen, and in this case, 5AD1 of memory 5 = 0000.
, LN1 of the other memory 6 is 400. When the display address generation circuit 3 outputs address data 0000, the contents of address 0000 are read from the VRAM 2 and sent to the display device 4 as serial data via the S-P conversion circuit 9. Then, when 16 bits are displayed, the address is 1. The upLOOO1 address is output. At the same time, LNI becomes 400-1=399, and the display address is incremented until this counter LNI eventually reaches O.

For example, if the display address is set to IF40 and the counter LNI is set to 200, the contents of 200 lanutas from IF40 of VRAM2 to address 3E7F will be displayed on the CRT.
It is displayed in the upper half of the display screen 4, and then the display address is set to 0000, and at the same time the counter LN2=200.
When 200 is set in counter 7 from V R,A
1 from address 0000 of M2. The contents up to F40'ffI' are displayed in the lower half of the CRT display screen. This situation is shown in FIG.

If you operate the scroll switching keys S and L on the keyboard 10 during scrolling, a flag (F
LAG), and by determining 1.0 of this flag in the scroll routine shown in FIG. 5, a line crawl or smooth scroll is executed. By the way, Figure 6 shows an example of 5-character scrolling. Initially, when flag 1 is used to perform a line crawl, when the switch key S is pressed at part (A), the flag is reversed to O, and ( You can switch to smooth scrolling from part b).

If the counter 5ADI is set to 0000 and the LNI is set to 400 before scrolling, and the number of rasters for one line is now 16 rasters, the counter 5AD1 is set at step S1 during line scrolling, as shown in the flowchart of FIG. =SAD1+500. SA, D2
=OOOO.

LN1=LN1-16. Set LN2=LN2+16, determine whether LNI is 0 in step S2, and set 0.
If so, proceed to step S3 and 5ADI=OOOO, LN1
=400 and the process proceeds to step S4. If the value is 0, the process directly proceeds to step S4.

Then, in step S4, after scrolling, 500 bytes of data are rewritten at a time so that one line at the top of the CRT is displayed at the bottom. This situation is as shown in FIG.

On the other hand, for smooth scrolling, set 16 to counter 7 (SL), 5AD1=SAD1+50.5AD
2=OOOO1L N 1. = L N 1. -1,
Set L N 2 = L N 2 + 1 S2
), it is determined in step S3 whether LNI is 0 or not. If it is 0, in step S4 SAD]-0000
, set LN 1 =400 and proceed to step 35.
If it is not 0, the process directly proceeds to step S5. Step S5
Now, in order to display the contents displayed in the first and second place of the CRT in the last one raster after scrolling, data for one raster is rewritten. Then, in step S6, the content of the counter 7 is subtracted by one, and in step S7, the content of the counter is determined to be 0.
Otherwise, the process returns to step S2. Therefore, on the CRT, the display of each lanutre is repeated 16 times in total, resulting in one character block (see FIG. 9).

In this way, by operating the switching keys S and L of the keyboard 10 during scrolling, it is possible to immediately switch the display from line scroll to smooth scroll or vice versa.

<Effects> As described above, the number scroll switching method of the present invention is configured so that the number scroll routine or the line scroll routine can be executed in response to the operation of the scroll switching key on the keyboard, and the scroll switching method of the present invention is configured so that the number scroll routine or the line scroll routine can be executed in response to the operation of the scroll switching key on the keyboard. Since you can immediately switch to another scroll display by operating the switch key, you can easily switch to either scroll display depending on your purpose.

[Brief explanation of drawings]

Figure 1 is a block circuit diagram of a personal computer adopting the method of the present invention, Figures 2 and 3 are diagrams showing the address relationship between the VRAM and the display device, and Figure 4 is the display position of the VRAM data on the display device. Fig. 5 is a diagram explaining the scroll routine, Fig. 6 is an operation flowchart when scrolling for 5 characters, Fig. 7 is a flowchart of line scrolling, and Fig. 8 is a flowchart 1-1 of smooth scrolling. FIG. 9 is a diagram showing the state of the VRAM and display device during smooth scrolling and line scrolling. 2 is a central processing unit, 2 is a video ram, 3 is a display address generation circuit, 4 is a display device, 5 and 6 are memories, 7 and 8 are counters, 10 is a keyboard, and S and L are scroll switching keys. Deputy Patent Attorney Aihiko Fukushi (and 2 others) No. 1□□□ No. 1, No. 8, Ward 7

Claims (1)

[Claims] 1. In a device that is equipped with a device that displays display data by scanning multiple lines and a keyboard, and that is capable of smooth scroll display and line scroll display on the display screen, the smooth scroll display can be performed in response to the operation of a scroll switching key provided on the keyboard. A scroll switching method characterized in that the scroll switching method is configured to be able to execute a null scroll routine or a hall line scroll routine, and is configured such that the display can be immediately switched to another scroll display by operating the scroll switching key while the scroll is being executed. .