JPS62109089A - Display control 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] [Field of Industrial Application] The present invention relates to a control method for a display device used as an output device of an information processing system, and in particular a multi-window control method for displaying multiple display areas in an overlapping manner. This invention relates to a display control method for control.

[Conventional technology]

Conventionally, CRT is a typical example of this type of display device.
There is a display device, which is a CRT (cathode ray tube).
It has a video ram (refresh memory) which is a display memory corresponding to each display dot on the display surface. CR
This video ram is read every T refresh cycles to refresh the CRT.

In addition, in this type of display control system, as shown in FIG. 2, by partitioning a plurality of display areas 12a and 12b on this video ram 11, a multi-window for simultaneously displaying a plurality of display contents can be created. control is in place. In this multi-window control, the display areas 12a and 12b are partitioned so as to overlap each other, and the content of the area with a higher priority is written in the video ram 11 in the overlapping area. However, since the priority can be changed sequentially, each display area 12a stores the area hidden below as a result of overlapping.

Therefore, when updating the display area, the window memory is first updated, and then a means for moving rectangular areas called a mover is used to move the rectangular area. I was transferring it from wind memory to video ram while taking everything into consideration.

[Problem that the invention seeks to solve]

The conventional method described above includes window memo IJ e update,
Each time the transfer is performed, the mover is used for transfer, which has the disadvantage that the processing is delayed by the amount of time the mover operates.

Updating the window memory is usually triggered by a command that is started by a higher-level application program, but this command is often issued several times in succession, and it is difficult to update the window memory per command. The time is often short, from a few milliseconds to several tens of milliseconds.

On the other hand, since the results of the CRT output are viewed by the operator, it is sufficient for the video ram update cycle to range from several hundred milliseconds to several seconds.

[Means for solving problems]

The display control method of the present invention includes a rectangular area storage register for storing the rectangular area in the window memory to be transferred to the video RAM, a command end timer restarted at the end of a command, and a Creates a new rectangle containing both the periodic timer that times out, the rectangle in the updated range when the window is updated, and the rectangle already stored in the rectangle storage register. A means for updating the rectangular area storage register by determining the command end timer, and when the periodic timer times out and the window memory has been updated since the previous periodic timer timed out. , means for activating the mover using the value of the rectangular area storage register as a parameter.

〔Example〕

FIG. 1 shows an embodiment of the present invention. A mover 14 is interposed between the window memory 13a corresponding to a certain display area, the window memory 13b corresponding to another display area, and the video ram 11, and the data is transferred under the control of a control unit 20 that controls the overall processing order. I do. A rectangular area storage register for storing a rectangular area in the window memory to be transferred to the video RAM 11 is composed of an upper left coordinate register 15 and a lower right coordinate register 16. Comparators 17 and 18 are provided to compare the contents of these registers and the coordinates, and a command end timer 21, a synchronization timer 22, and an update flag 23 are also provided.

Initially, the update flag 23 is set to 0. Furthermore, as will be described later, the update flag 23 remains O even after the mover 14 operates. At this time, when the window memory 13a is updated by a command, the updated rectangular area is found, and its upper left coordinates are stored in the upper left coordinate register 15.
Further, the lower right coordinates are written to the lower right coordinate register 16, the update flag 23 is set to 1, and the command end timer 21 is started.

When an application program issues commands continuously, the next command is accepted before the command end timer 21 times out, and the window memory 13
a is updated. In this case as well, the updated rectangular area is found, but since the update flag 23 is 1 at this time, the upper left coordinates 24 and lower right coordinates 25 of the updated rectangular area, the upper left register 15, and the right The contents of the lower register 16 are compared by comparators 17 and 18, respectively, and these registers are updated. This update is performed as follows. In other words, the coordinates of the rectangular area in each register are expressed as values in the X and Y directions, but the upper left of the rectangular area updated this time is (XLN a YuN), and the lower right is (XRN *
YDN), and the value of the upper left coordinate register 15 is (Xmio
, Ymln), and set the value of the lower right coordinate register 16 to (Xmax
+ Ymax), when XLN < Xm1n, XLN is the new value of Xm1n, and YON < Y
When min, let YUN be the new value of Ymin,
When XRN > XmaxO, set XRN to the new value of Xmax; when YRN > Ymax, set YRN to Ym
Let be the new value of ax. Furthermore, the command end timer 2
1 and waits for either the next command to be issued or for the value of this timer 21 to elapse.

This process is repeated as long as the commands continue.

When the command is interrupted, the command end timer 21 times out. In this case, the upper left coordinate register 15
Then, the contents of the rectangular area in the window memory 13a specified by the lower right coordinate register 16 are transferred to the video ram 11 using the mover 14, and the update flag 23 is returned to O.

Further, a period timer 22 is provided to update the CRT display at a period that satisfies the operator even when commands are issued continuously for several seconds or more. In other words, the periodic timer 22 times out at regular intervals,
If the update flag 23 is 1 at that time, the contents of the rectangular area in the window memo IJ 13a specified by the upper left coordinate register 15 and the lower right coordinate register 16 are transferred to the video ram 11 using the mover 14. The update flag 23 is returned to O.

The window memory 13b also operates in the same way, but when the mover 14 moves the window memory 13b, the window memory IJ
The portion hidden under 13a will not be transferred. Window memo regarding the fact that the part hidden under another window memory is not transferred. The same holds true even if the overlapping relationship between j13a and j13b changes.

Figure 1 shows an example where there are two window memories.
The present invention can be similarly applied even if there are three or more.

〔Effect of the invention〕

As explained above, the present invention updates the contents of the window memory updated by multiple commands at regular intervals when the commands are interrupted for a certain period of time or more, and when commands are issued continuously. By using a mover to transfer data to the video ram and reducing the number of times the mover is used, it is possible to improve the overall processing speed and obtain a display update time that satisfies the operator.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing an outline of the operation of multi-window control. DESCRIPTION OF SYMBOLS 11... Video RAM, 13a... Window memory A, 13b... Window memo IJB, 14... Mover, 15... Upper left coordinate register (Xmi.sYmin) as rectangular area storage register, 16 ...Lower right coordinate register (Xmax
, Ymax), 17. 18... Comparator, 20... Control unit, 21... Command end timer, 22... Period timer, 23... Update flag, 24... Upper left coordinate (
XLN e YUN), 25...lower right coordinate (XaNm
YDN). sweat twice

Claims (1)

[Claims] (1) A rectangular area storage register for storing the rectangular area in the window memory to be transferred to the video RAM, a command end timer that is restarted when the command ends, and a periodic timer that times out at fixed intervals. , when the inside of the window is updated, a new rectangular area that includes both the updated rectangular area and the rectangular area already stored in the rectangular area storage register is calculated and the rectangular area is stored. A means for updating the register, and a rectangular area when the above-mentioned command end timer times out, and when the above-mentioned periodic timer times out and the window memory has been updated since the previous periodic timer timed out. and means for activating transfer to the video ram using the value of the storage register as a parameter.