JPS58159576A - Scroll display controller - 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 of the Invention The present invention relates to a display control device with an improved scroll display method.

(B) Background of the technology Display devices are very suitable as computer output devices and are widely used in large, medium, and small computers, but various auxiliary functions are used to enhance the display effect. . Scroll display is one type of such a function, and is considered to be a particularly useful function in systems where interactive processing is performed while looking at the display screen.

(0 Prior Art and Problems Figure 1 shows a conceptual diagram of a scroll display in a conventional display device. In the figure, 1 is a display surface, 2 is a screen memory, and 3 is a conceptual diagram of a scroll display in a conventional display device.
is the first logical screen memory; and 4 is the second logical screen memory. The screen memory 2 is provided corresponding to all display degrees forming the display surface 1, and the contents thereof are displayed on the display surface 1 as they are. Therefore, display surface 1
In order to display the desired data on the screen, it is necessary to directly store this data in the 5-screen memory 2.

In the illustrated example, display surface 1 is displayed at display position A,! : Divided into two areas B, the screen of the first logical screen memory 3 is scroll-displayed in the area A, and the screen of the second logical screen memory 4 is scroll-displayed in the area B. , in order to do so, the screen memory 2 is divided into A' and B' corresponding to the display surface 1.
The screen of the first logical screen memory 3 and the screen of the second logical screen memory 4 must be scrolled and written in the areas A' and B', respectively. For this reason, there was a problem in that displaying required time.

(2) Purpose of the Invention An object of the present invention is to provide a scroll display control device with increased display speed.

(G) Structure of the Invention The scroll display control device according to the present invention includes an address register provided corresponding to each of a plurality of logical screen memories and for setting a display start address, and an address register selected by selecting the address register. a first multiplexer that outputs a display start address set in the first multiplexer; an address counter that sets the display start address output by the first multiplexer and increments a count value each time about one fist of data is read; a line number register provided corresponding to each of the logical screen memories and setting the number of display lines; a second multiplexer that selects the line number register and outputs the number of display lines set in the selected line number register; , a line number counter that sets the number of display lines output by the second multiplexer and decrements a count value each time one display line of data is read; a screen number register that sets the number of screens to be displayed; and a screen number register that sets the number of screens to be displayed; The scroll display speed is increased by eliminating the three-screen memory in the conventional example.

(g) Examples of the invention Next, the gist of the present invention will be specifically explained using examples.

FIG. 2 shows a block diagram of the main parts of an embodiment of the present invention. In the figure, 5 is an address register provided corresponding to each of a plurality of logical screen memories and sets a display start address, and 6 is an address register 6. The first multiplexer 7 selects and outputs the display start address set in the selected address register, and 7 sets the display start address output by the first multiplexer 6, and increases the count value every time one unit of data is read. An address counter 8 is a line number register provided corresponding to each of the plurality of logical screen memories and sets the number of display lines; 9 selects the line number register 8 and displays the line set in the selected line number register; A second multiplexer 10 outputs a number, and 114 is a line number counter that sets the number of display lines output by the second multiplexer 9 and decrements the count value each time data on a display line is read.
− is a screen number register that sets the number of screens to display, 12
is a screen counter that counts the number of displayed screens.

In the above configuration, initially, the display start address set in the first address register a of the address registers 5 is set in the address counter 7, and the display start address is set in the first line number register a of the line number registers 8. The set display line number is set in the line number counter 10, a predetermined range of the first logical screen memory is displayed, and when the count value of the line number counter 10 reaches #0#, the screen number counter 12 is set to “ 1", the first multiplexer 6 sets the display start address set in the second address register b of the address register 5 to the address carantuff, and the second multiplexer 9 sets the display start address set in the second address register b of the address register 5, and the second multiplexer 9 is set in the display line number counter 10 set in the line number register b, and a predetermined range of the second logical screen memory is displayed. After that, calculate the number of screens in the same way, and select Fist J 1 1 f JF -L
J(Jq −に−4hys−;q;tx k
The L Δ~=yh range is divided and displayed on the display screen, and when the count value of the screen number counter 12 matches the value set in the screen number register 11, the display returns to the first logical screen memory again and the display is repeated. Therefore, scrolling display is performed by scrolling and setting each display start address in address register 5 for the screen memory to be scrolled.

(G) Effects of the Invention As explained in the embodiments, according to the present invention, the screen memory in the conventional example is eliminated and the logical screen memory is used as the screen memory in the conventional example, so scrolling display can be performed at high speed. 0

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of a scroll display in a conventional display device, and FIG. 2 is a block diagram of main parts of an embodiment of the present invention. In FIG. 2, 5 is an address register, 6 is a first multiplexer, and 7 is an address counter, 8 is a row number register, 9 is a second multiplexer, 10 is a row number counter,
11 is a screen number register, and 12 is a screen number counter.

Claims (1)

[Claims] In a device that divides a display screen into a plurality of areas in display rows and scrolls and displays a plurality of screens in each of the divided areas, a display screen that corresponds to each of a plurality of logical screen memories storing the plurality of screens is provided. an address register for setting a display start address; a first multiplexer for selecting the address register and outputting the display start address set in the selected address register; and a display start address output by the first multiplexer. an address counter that increases the count value each time data of 1 Rin is read; a line number register that is provided corresponding to each of the plurality of logical screen memories and sets the number of display lines; and a line number register that sets the number of display lines. A second multiplexer that selects and outputs the number of display lines set in the selected line number register, and a count value that sets the number of display lines output by the second multiplexer and reads a count value every time data of one display line is read. It is characterized by comprising a line number counter to be decremented, a screen number register to set the number of screens to be displayed, and a screen number counter to count the number of displayed screens, and to scroll and display a plurality of screens on the display surface. Scroll display control device.