JPS59176833A - Display system - Google Patents

Abstract

PURPOSE:To reduce the load of a CPU and to shorten the data transmission time by attaining a dynamic display on a screen just with the transfer of the program transfer data to a processor unit from the CPU. CONSTITUTION:The code of the data to be displayed is stored in a data memory 41, and a screen memory 42 is divided into a data region and an order region. The order region stores a display control program consisting of a prescribed order in order to perform a display in a prescribed format. While the data region stores the data which is referred to by an order setting up a flag at a prescribed bit position of the display control program in the form of the program transfer data. A firmware 62 sets a pointer in the memory 42 at 1 by a command of a CPU3 and then executes the display control program in turn from its head to develop the screen up to a refresh memory 2.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] This invention relates to a display system for efficiently performing dynamic display. [Prior art and its problems] Fig. 1 shows the configuration of a conventional display system. It is a diagram. In the figure, reference numeral 1 indicates a refresh memory for, for example, a CRT display device 12, reference numeral 3 indicates a central processing unit (CPU), and reference numeral 4 indicates a memory 5 in which screen data is stored, a command register. Here, when displaying one character, for example, on the CRT display device 1, the CPU 3 inputs the address (position on the display screen), character color, background color, character code, etc. to the command register 5 of the CRT display device 1. By outputting an order (command or instruction) including data from the memory 4, predetermined characters are output to the corresponding area of the refresh memory 2 and displayed on the CULT display screen.

In such a display system, when displaying part of the display screen dynamically, the address, font color, background color, character code, etc. are output each time to display one character, so the number of characters to be displayed or changed, the color, etc. As the number increases, the amount of data transferred from the CPU increases, which has the disadvantage of not only increasing the transfer time but also increasing the burden on the CPU.

[Purpose of the invention]

This invention was made to eliminate the above-mentioned drawbacks, and its purpose is to reduce the amount of data transferred from the central processing unit and send only the minimum amount of data, thereby reducing the burden on the central processing unit and making it easier to use. The object of the present invention is to provide a display system capable of dynamic display.

[Key points of the invention]

The present invention relates to a display system that displays data stored in a fresh memory based on instructions from a central processing unit (CPU), in which a series of orders (commands) are sent to the display device to display data in a predetermined format. A screen memory is provided for storing a plurality of display control programs consisting of a plurality of display control programs, and program passing data referred to by at least one of the orders, so that a desired display can be easily performed simply by sending the program passing data from the CPU. That's what I did.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing an embodiment of the invention, and FIG. 3 is a block diagram showing the structures of a data memory and a screen memory.

In FIG. 2, 41 is a data memory, 42 is a screen memory, 6 is a display control device consisting of a processor 61 and firmware 62, and other symbols are the same as those shown in FIG. As shown in FIG. 3(A), data to be displayed, for example, codes of letters A to G, are stored in the data memory 41 as shown in the figure.

The screen memory 42 is divided into a data area DAT and an order (instruction or instruction) area O as shown in FIG. Predetermined order oDggi~6
A display control program consisting of
Data DATA1-3 referenced by those marked with an asterisk (onEg3, 4.s) among the above-mentioned orders 0DER1-6 are stored in the AT, respectively.

Note that the order ranges from 0DERI to n, but here it is 0
It is assumed that one display control program is formed by DERI-6. This data DATA1-3 is CP
This data is transferred from the data memory 41 by an order of, for example, 5TORE from U3, and will be referred to as "program transfer data" here. Therefore, the third
It can be said that the orders 0DER3, 4, and 5 shown in FIG. Note that there are generally n display control programs stored in the screen memory, and which of the orders constituting each program will be of a format that refers to program passing data is determined in advance for each program. In such a case, it is possible to distinguish between orders that refer to program-passed data and those that do not by setting a 7 lag at a predetermined bit position of the corresponding order.
The data that the order ODE 3 should refer to is DATA1,
Same (For ODER4, DATA2.0 For DER5, there is a one-to-one correspondence like DATA3, therefore, data DATA1-3 are associated with each order 0DER3-5
They are referred to sequentially from the top of the figure, and the order at this time is specified by a pointer (a type of counter) 43. That is, the pointer is reset to "1" every time the CPU 3 gives the above-mentioned STO E order to the processor unit 61, and is incremented by 1 every time the firmware 62 executes an order that refers to program-passed data. , whereby the data DATA1 to DATA3 are referenced in order.0 Figure 4 is a flowchart for explaining the operation of Figure 2.1 Figure 5 explains the display screen that changes due to the operation as shown in Figure 4. When the program consisting of (a) to (f) is started as shown in FIG. 4, the following operations are performed.

(a) The CPU 3 transfers the program passing data DATA1. DATA2, DATA
3 is sent to the processor unit 61 as a parameter of the 5TORE order. Here, the content of DATAI is the code of character A, DATA2 is the code of character B, DAT
Assume that A3 is the code for the letter C.

(b) When the processor unit 61 receives the 5TORB order, the firmware 62 reads DATA1-D.
After storing ATA3 in the program passing data area DAT of the screen memory 42 and setting the pointer 43 in the screen memory 42 to "l", the display control order is set to 0D.
The screen is executed in order starting from ERI, and the screen is expanded to the refresh memory 2. Order 0D executed in this case
It can be seen that the ER3 is of a format that refers to the program-passed data using the flag as described above, so the firmware 62 uses the DAT indicated by the pointer 43 above.
Refer to the A code of Al and refresh this to memory 2.
Write to. When 0DER3 is executed, pointer 43
is incremented by 1 and the next block is passed to lx data DATA2.
is specified, the data is referenced by order ODE 4, and the code of character B, which is the content of DATA2, is written to refresh memory 2. Similarly, the code of character C is written to the 9th frame by order 0DER5. The data is written to the storage memory 2. In this way, the characters <A, B, and C are displayed on the CD/T display device 1 as shown in Figure 5 (r).

(C) Subsequently, the CPU 3 transmits the next program passing data DATA2 and DATA3 to the processor unit 61 in the same manner as in the case of (a) above. D in this case
The contents of ATA2.3 are the codes of letters E and F, respectively.0 Cd) The processor unit 61 transfers the data DATA to the program passing data area 1DAT of the screen memory 2, as in the case of E (b) above.
2.3 and pointer 4 in screen memory
3 to 1''. At this time, the data DAT
The content of the AI remains the same as before, and is the code for the letter A. From then on, the firmware 62 executes the display control orders one after another, and writes the letter A and Fli to the corresponding area of the recipe memory 2.
, F, the letter A is written as shown in Figure 5 (b).
, B, and C, characters A, E, and F are displayed on the display device 2.

(e) Next, the CPU 3 transmits DATA3 as data in the data memory 41 to the processor unit 61. It is assumed that the content of this DATA3 is the hood of the letter G.

(When the processor unit 61 receives the 5TORE order, it passes DATA3 to the program and transfers it to the data area DAT.
At the same time, the pointer 43 is set to "1". Thereafter, by executing display control orders 0DBR1 to 0DBR6 in the same manner as above, A and E are stored in the corresponding areas of the 1 refresh memory 2.

Since the letter G is expanded, the display device will display Figure 5 (C).
In the above example, the letters A, B, and G are displayed, as in
The number of data to be passed to the program is three, DATA1 to DATA3, and the contents are only character codes, but data such as addresses and character colors can also be passed to the program, and the number of data can also be changed. It can be selected arbitrarily.

〔Effect of the invention〕

As described above, according to the present invention, dynamic screen display is performed simply by providing a screen memory and a data memory and transferring program-passing data from the CPU to the processor unit, thereby reducing the amount of data transferred from the CPU. This can be minimized, and therefore the load on the CPU can be significantly reduced. Furthermore, the reduction in the number of data transfer sources has the effect of shortening the transfer time.

Note that although the CRT display device has been described above, the present invention can be applied to general display devices similar to this.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a conventional example of a display system, Fig. 2 is a block diagram showing an embodiment of the present invention, Fig. 3 is a block diagram showing the structure of data memory and screen memory, and Figure 4 is a block diagram showing the present invention. Flowchart for explaining the operation in 5th
The figure is an explanatory diagram showing a display screen after executing a program delivery order. Description of symbols 1...CRT display device, 2...Refresh memory, 3...Central processing unit (CPU)
, 4...Memory 1.41...Data memory, 42...Screen memory, 43...
Display pointer, 5.--.command register)6.
--- Display control device, 61 --- Processor unit, 62 --- Firmware agent Patent attorney Akio Namiki Patent attorney Kiyoshi Matsuzaki Figure 1 Figure 2

Claims (1)

[Claims] In a display system that receives commands from a central processing unit to display data stored in a refresh memory, a first area stores a plurality of display control programs consisting of a series of orders for displaying in a predetermined format; a screen memory having a second area for storing display data referenced by at least one of the orders corresponding to the order; and display data corresponding to the predetermined order sent from the central processing unit together with a predetermined command. are sequentially stored in the second area of the screen memory, and while referring to the display data stored in the second area, the display control program is sequentially fetched and executed from the first area of the screen memory to refresh the data to be displayed. 1. A display system comprising: a display control means for expanding in a memory; and display data corresponding to a predetermined order is sent from a central processing unit to the display control means, thereby displaying the predetermined data in a predetermined format.