JPS5837547B2 - Display method in CRT display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a screen display method in a CRT display device having a screen storage medium.

In CRT display devices, as the number of types of screens to be displayed increases, a magnetic storage medium such as a flexible disk cartridge (FDC) is used to store the screens.

Display programs corresponding to each screen are stored in such a screen storage medium, and the main . transferred to memory and executed.

Conventionally, the screen display on a CRT starts after the transfer of the display program is completed, so it takes a certain amount of time from the time the screen is called until the screen actually appears, giving the operator a sense of urgency. Ta.

Also, since the screen display is done by a display program, changing the screen format requires changing the display program.

An object of the present invention is to provide a display method for a CRT display device having a screen storage medium, which can quickly display a screen in response to a call, easily change the screen format, and reduce the burden on a display control computer. It is in.

The present invention stores information related to a screen separately as screen data and a program in a screen storage medium, and in response to a call, first transfers the screen data to a refresh memory by direct memory access (DMA), Next, transfer the program to the main memory execution area, and
The screen data is refreshed by transferring the screen data from the storage medium to the refresh memory and displaying the contents of the refresh memory on the CRT in a time-sharing manner. The data is displayed on the CRT sequentially as soon as it is transferred to the memory.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a conceptual diagram of an embodiment of the present invention.

In Figure 1, 0 is the main memory and 1 is the micro memory.
A computer consisting of a processor, etc.; 2 is a DMA control circuit; 3 is a DMA control circuit;
is an interface for a screen storage medium, 4 is a screen storage medium such as an FDC, 5 is a refresh memory, and 6 is an address. Selector, 7 is transfer direction controller, 8 is CRT
The control circuit 9 is a CRT.

Main memory 0, computer 1, DMA control circuit 2, and interface 3 are connected by a data bus.

A screen storage medium 4 is connected to the interface 3.

A refresh memory 6 is connected to the data bus through a transfer direction controller 7.

The address of the refresh memory 6 is specified by the output of the selector 5.

The selector 5 alternately selects an address given from the computer 1 or the DMA control circuit 2 and an address given from the CRT control circuit 8.

For example, as shown in FIG. 2, the selection switching cycle is set equal to the display time of one character on the CRT.

When the selector 5 selects the address given from the computer 1 or the DMA control circuit 2, the computer 1 rewrites the data in the refresh memory 6 or the DMA
DMA transfer between the refresh memory 6 and the screen storage medium 4 by the control circuit 2 can be performed.

When the selector 5 selects the address from the CRT control circuit 8, the CRT 9 of the data in the refresh memory 6
The transfer will take place.

FIG. 3 shows the arrangement of screen information in the screen storage medium 4 and its transfer status.

In FIG. 3, the screen information is in the form of one file per screen, and one file consists of a file label, screen data, and a program.

Of these, screen data and programs are transferred to refresh memory 6 and main memory 0, respectively, by DMA in response to calls.

The screen data is structured in a format such as 8-unit code according to the JIS standard, which can be displayed immediately after being transferred to the refresh memory.

The operation of the device configured in this way is as follows.

When the operator operates a keyboard (not shown) to call up one screen in the screen storage medium 4, the DMA control circuit 2
As a result, DMA transfer from the screen storage medium 4 to the memory space is started.

DMA transfer first refreshes the screen data and transfers it to memory 6.
It starts by transferring to.

Even during DMA transfer, refresh is performed by the operation of selector 5. Since addresses from the DMA control circuit 2 and addresses from the CRT control circuit 8 are alternately given to the memory 6, DMA transfer and CRT display are performed in a time-sharing manner, and screen data is transferred to the refresh memory 6 as soon as it is transferred. It is immediately displayed on the CRT9.

As a result, the operator can wait at most for the access operation time of the screen storage medium 4 after calling up the screen.
Since I can see the appearance of the desired screen, I almost never feel anxious.

The main task is to transfer the program after the screen data has been transferred.
This is done for the execution area of memory.

When the program transfer is completed, the screen data in the refresh memory 6, that is, C
The data displayed on the RTS can be manipulated.

Therefore, the operator cannot manipulate the displayed data until the program transfer is completed, but this is not a particular inconvenience since there is rarely a need to manipulate the displayed data in a timely manner.

In addition, if the screen data is transferred to the refresh memory 6, such as the 8-unit code of the JIS standard,
Since the data is in a format that can be displayed, it is much easier to create and modify it than in the conventional case.
Therefore, it is easy to change the screen format.

In addition, the screen data is brought from the screen storage medium 4 to the refresh memory 6 by DMA, and is given to the CRT by the autonomous operation of the CRT control circuit, so the time occupied by the computer 1 for screen display is extremely short. This will greatly reduce the burden on the computer.

As described above, the present invention stores screen-related information separately in screen data and programs in a screen storage medium, and in response to a call, first transfers the screen data to the refresh memory by DMA, and then transfers the program to the execution area. In addition, the DMA transfer of screen data and the CRT display of the contents of the refresh memory are performed in a time-sharing manner.

Therefore, it is possible to realize a display method in which the screen can be quickly called up, the screen format can be easily changed, and the burden on the display control computer is light.

[Brief explanation of the drawing]

FIG. 1 is a conceptual structural diagram of an embodiment of the present invention, and FIGS. 2 and 3 are operation explanatory diagrams.

Claims (1)

[Claims] 1. In a CRT display device having a screen storage medium, information about the screen is divided into screen data in a format that can be directly displayed and a program and stored in the screen storage medium, and in response to a screen call, the screen data is first refreshed and stored in the memory. Direct to. Transfer by memory access, then program to main. Transfer to the execution area of memory, transfer screen data from storage medium to refresh memory, and refresh. CR of memory contents
A display method that performs multiple displays on a time-sharing basis.