JPH05333832A - Selective display system for video signal - Google Patents

Abstract

PURPOSE:To prevent devices of the video signal selective display system, which selects and displays video signals from plural video control circuits on a display device, from increasing in size, to easily switches the video signal outputs of the video control circuits, and to prevent jitters, etc., from being generated. CONSTITUTION:When an operator commands a video display, a CNC(computer numerical control) function part sends a switching flag to work memories 25 and 34. For example, when a video control circuit 2 is put in operation. the CNC function part sets the switching flag to 0 and sends it to the work memories 25 and 34. In this case, the MPU 21 of the video control circuit 2 sends a drive signal to a drive circuit 26, which then outputs a video signal. At this time. the MPU 31 on the side of the video control circuit 3 does not output the drive signal, so the video signal is sent from only the drive circuit 26 and displayed on the screen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal selection display system for selecting video signals from a plurality of video control circuits and displaying them on a display device, and more particularly to a video signal from a video control circuit selected by an operator. The present invention relates to a selection display method of a video signal for displaying.

[0002]

2. Description of the Related Art Generally, a numerical control device or the like is provided with a graphic function to be prepared and used by a user in addition to a graphic function provided by a maker in advance. Each of these graphic functions is connected to the motherboard as a video control circuit module.

However, since only one of the video control circuits is actually used by the user, it is necessary to switch to the video control circuit to be used when supplying a video signal to the display device. Therefore, according to the conventional technique, it is conceivable that the output terminal of each video control circuit is connected to the display device via a manual switching device so that the operator can switch and select.

[0004]

However, since the manual switching device uses a large number of relays, there is a problem in that each of the RGB signals varies and jitter easily occurs. There is also a problem that the entire numerical control device becomes large in size by providing an extra device.

On the other hand, in order to solve this problem, a method of integrating graphic functions can be considered. However, since the graphic system provided by the manufacturer and the graphic function used by the user differ in the command system of the processor, the required video control circuit, etc., it is time-consuming to integrate them by software. There was a problem.

The present invention has been made in view of the above circumstances, and it is possible to prevent the device from becoming large in size, to easily switch the output of the video signals of a plurality of video control circuits, and to prevent jitters and the like. It is an object of the present invention to provide a video signal selective display method that can be performed.

[0007]

According to the present invention, in order to solve the above problems, a video signal selection display system for selecting video signals from a plurality of video control circuits and displaying them on a display device is specified by an operator. Display command means for sending a display command signal to the video control circuit, video signal output command means provided in each video control circuit for issuing a video signal output command only when the display command signal is received, and each video control circuit A drive circuit that is provided inside and is wired-OR connected to the output of another video control circuit, and that outputs a video signal generated by the graphic control circuit to the display device only when receiving the video signal output command, There is provided a video signal selective display system characterized by having.

[0008]

The display command means sends a display command signal to the video control circuit designated by the operator. The video signal output command means in the video control circuit issues the video signal output command only when the display command signal is received, and the drive circuit provided in the same video control circuit receives the video signal output command. Only at this time, the video signal generated by the graphic control circuit is output to the display device. Since the output of the drive circuit of each video control circuit is connected by wired OR, only the video signal of the video control circuit designated by the operator is output to the display device.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram showing the configuration of the video signal display unit of the numerical control device. The CNC function unit 1 that controls the entire numerical control device is connected with other modules (not shown) such as the video control circuit 2, the video control circuit 3, and the spindle control function unit via the common bus 4 of the motherboard. There is.

The video control circuit 2 is provided for the user, and its output is connected to the CRT / MDI unit 5. On the other hand, the video control circuit 3 is system-designed by the manufacturer, and its output is connected to the CRT / MDI unit 5 via the video control circuit 2.

The CRT / MDI unit 5 is a display device 5.
It is composed of a and a keyboard 5b. The video signal sent from the video control circuit 2 or the video control circuit 3 is displayed on the screen of the display device 5a. On the keyboard 5b, the operator operates the screen, and the key input signal is sent to the CNC function unit 1. The CNC function unit 1 decodes the key input signal and decodes the video control circuit 2
Alternatively, the video data is sent to the video control circuit 3, and the video signal is output to the display device 5a.
Alternatively, a command to switch to that of the video control circuit 3 is issued. The CNC function unit 1 reads the video switching state requested by the operator and sends a switching flag described later to the video control circuit 2 and the video control circuit 3.

FIG. 1 is a block diagram showing a specific configuration of the video control circuit 2 and the video control circuit 3. The video control circuit 2 on the user side is controlled by the MPU 21, which is connected to the ROM 22 and RA via the bus 27.
M23, graphic control circuit 24, work memory 2
5 and drive circuit (DR) 26 are coupled.

The ROM 22 stores a system program for controlling the entire video control circuit 2.
An application program created by the user is stored in the RAM 23. Graphic control circuit 24
Generates a video signal according to this application program and sends it to the drive circuit 26.

The work memory 25 also stores a switching flag sent from the CNC function unit 1. The switching flag is bit data of 0 or 1, and the switching flags having the same contents are simultaneously sent to the video control circuit 2 and the video control circuit 3. The MPU 21 periodically reads the switching flag of the work memory 25 and, if the content is 0, sends a drive signal to the drive circuit 26. When receiving the drive signal from the MPU 21, the drive circuit 26 outputs the video signal generated by the graphic control circuit 24 to the display device 5a.

On the other hand, the video control circuit 3 on the manufacturer side is M
Controlled by the PU 31, the MPU 31 is connected to the bus 3
The ROM 32, the graphic control circuit 33, the work memory 34, and the drive circuit (DR) 35 are connected via the unit 6. The ROM 32 stores a system program for controlling the entire video control circuit 3 and a graphic program created by the manufacturer.

The graphic control circuit 33 generates a video signal according to a graphic program and sends it to the drive circuit 35. Further, the same switching flag as that stored in the work memory 25 of the video control circuit 2 is sent from the CNC function unit 1 and stored in the work memory 34.

The MPU 31 periodically reads the switching flag of the work memory 34, and if the content is 1, for example, sends a drive signal to the drive circuit 35. Upon receiving the drive signal from the MPU 31, the drive circuit 35 outputs the video signal generated by the graphic control circuit 33.

The output of the drive circuit 35 is drawn into the video control circuit 2 through a connector (not shown) and is wired-OR connected to the output of the drive circuit 26.

With such a configuration, in the video signal selective display system of this embodiment, when the operator gives a switching command, the CNC function unit 1 sends a switching flag to the work memories 25 and 34 in accordance with the command.

For example, when the operator operates the keyboard 5b to operate the video control circuit 2, C
The NC function unit 1 sets the switching flag to 0 and each work memory 2
5 and 34. In this case, M of the video control circuit 2
The PU 21 sends a drive signal to the drive circuit 26, which causes the drive circuit 26 to output a video signal.
At this time, since the MPU 31 on the video control circuit 3 side does not output the drive signal, the video signal is sent from only the drive circuit 26 to the display device 5a and displayed on the screen.

On the other hand, when the operator operates the keyboard 5b to operate the video control circuit 3, C
The NC function unit 1 sets the switching flag to 1 and each work memory 2
5 and 34. As a result, the video signal is sent from the drive circuit 35 only to the display device 5a and displayed on the screen by the same procedure as described above.

As described above, in this embodiment, the switching flag is sent to the two video control circuits 2 and 3 according to the instruction of the operator, and the video signal is output only from the drive circuit of the designated video control circuit. Therefore, switching control can be performed without providing a switching device between the video control circuit and the display device 5a.
Therefore, it is possible to prevent the occurrence of jitter and the like without increasing the size of the device.

Further, since the video control circuit can be separately provided on the user side and the maker side, it is not necessary to integrate software. For this reason, it does not take time and effort for manufacturing, and the cost can be reduced.

In the present embodiment, the video signal display unit of the numerical control device has been described as an example, but the present invention is not limited to this and can be applied to other video signal display devices. In addition, the number of switching targets can be selected and displayed from not only two but also more. In this case, a plurality of bits of data may be used instead of the switching flag.

The output of the switching flag may be performed by the MPU 21 or MPU 31, or another CPU.

[0026]

As described above, according to the present invention, the output of the drive circuit of each video control circuit is connected by wired OR, and only the video signal of the video control circuit designated by the operator is output to the display device. Therefore, it is possible to selectively display the video signals of the plurality of video control circuits without providing a switching device between the video control circuit and the display device. This makes it possible to prevent the occurrence of jitter and the like without increasing the size of the device.

Further, since it is not necessary to integrate a plurality of video control circuits in terms of hardware, there is no need to integrate software, no labor is required for manufacturing, and cost can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing a specific configuration of a video control circuit.

FIG. 2 is a block diagram showing a configuration of a video signal display unit of the numerical control device.

[Explanation of symbols]

 1 CNC functional unit 2 User side video control circuit 3 Manufacturer side video control circuit 4 Common bus 5 CRT / MDI unit 5a Display device 5b Keyboard 25, 34 Work memory 26, 35 Drive circuit

Claims (2)

[Claims] 1. A display command means for sending a display command signal to a video control circuit designated by an operator in a video signal selection display system for selecting video signals from a plurality of video control circuits and displaying them on a display device. Video signal output command means provided in each video control circuit for issuing a video signal output command only when the display command signal is received, and output of another video control circuit provided in each video control circuit and wired OR And a drive circuit which is connected and outputs a video signal generated by a graphic control circuit to the display device only when receiving the video signal output command. 2. The video signal selective display system according to claim 1, wherein a work memory for storing the display command signal is provided in each video control circuit.