TWI473495B - Controlling method for display device with narrow bezel or no bezel - Google Patents

Description

Control method for a narrow border or a borderless display

The present invention relates to a method of controlling a display, and more particularly to a method of controlling a display for a narrow bezel or a bezelless.

1 is a schematic diagram of a conventional wide bezel display. Referring to FIG. 1 , the frame 10 of the conventional display 1 generally adopts a wide bezel design. For example, the width W1 of the frame 10 is greater than 10 mm, so that there is sufficient space in the frame 10 to accommodate the driving circuit of the display panel 11 and A keypad 12 is provided on the bezel 10 to provide the control function of the display 1. The user can control the display 1 to operate normally or standby, switch channels, adjust the volume, or cause the display 1 to be displayed on the display panel 11 by On-Screen Display (OSD) technology by pressing a button on the keypad 12. Overprint the screen menu and operate this screen menu. The screen menu, also known as the OSD menu, is used to provide various settings for the display 1, such as brightness, contrast, chroma or white balance settings.

Recently, displays have adopted a narrow bezel design, for example, the width of the bezel is less than 10 mm, which is achieved by improving the arrangement of the driving circuit of the display panel. However, in order to set the keypad for providing the control function, some of the displays still need to adopt a wide bezel design in the frame of the button panel, which undoubtedly destroys the aesthetics of the frame of the display which adopts a narrow bezel design, and also loses with other Displays with narrow borders are used in combination to display large screens, and also increase manufacturing costs.

In view of this, the object of the present invention is to provide a control method for a narrow-frame or borderless display, which can provide a control function of the display without setting a keypad, so that the frame of the display can adopt a narrow frame design, or even With a borderless design.

The present invention provides a control method for a narrow-frame or borderless display, wherein the display includes a display panel, a touch module, a display driving module, and a micro controller, and the touch module It is used for sensing a touch input on the display panel to generate touch point information, the display drive module is configured to receive the video data and processed and transmitted to the display panel to display the screen, and the micro controller is configured to receive the touch point information. . When the display is in standby, the touch module works normally to sense whether the display panel has a touch input, and the display works normally until the touch panel input area of the display panel is touched. When the display is working normally and the screen is displayed, if the touch module senses that the touch panel area has a touch input, the micro controller controls the display drive module to overprint the key panel icon on the screen, and the key panel icon includes a power button Icon and menu button icon. When the display overprints the button panel on the screen, if the touch module senses that the button panel has a touch input and the micro controller determines to touch the menu button according to the touch point information, the micro controller controls The display driver module also overprints the screen menu on the screen.

The invention adopts the combination of the touch module and the driving board (including the micro controller and the display driving module), and changes the existing key board disposed on the frame of the display to a virtual key board image displayed on the display panel. The utility model not only maintains the user's habit of using the keypad for providing the display control function, but also adopts a narrow border or a borderless design because the display bezel no longer needs to set a physical keypad, thereby exhibiting a narrow border or a borderless It is aesthetically pleasing and can be combined with other frames with narrow borders or borderless designs to display large screens and reduce manufacturing costs.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

2A to 2C are respectively schematic views showing the use of a narrow-frame display according to an embodiment of the present invention. Referring first to FIG. 2A, the display 2 of the present invention adopts a narrow bezel design, for example, the width W2 of the bezel 20 is less than 10 mm, but as the technology advances, the standard for defining a wide or narrow bezel may be more stringent. For example, the width of the border must be less than 5 mm to be called a narrow bezel design. In addition, the display 2 of the present invention can also adopt a frameless design, that is, the width W2 of the bezel 20 is 0.

The display 2 can print or paste a button icon 201 on the frame 20 to prompt the user to have a button pad area 211 on the display panel 21 near the button icon 201. When the display 2 is in standby, the display 2 can supply power only to the touch module (not shown) to sense whether the display panel 21 has a touch input, and the display panel 21 without power supply is turned off. No screen display, until the touch module senses that the keypad area 211 has a touch input, the display 2 works normally and the display panel 21 is turned on to display the screen. When the display 2 works normally but the display panel 21 is closed without a screen display, once the touch module senses that the keypad area 211 has a touch input, the display 2 will open the display panel 21 to display a screen. Therefore, when the display 2 is in standby or normal operation but the display panel 21 is closed without a screen display, the user can determine the approximate position of the keypad area 211 according to the position of the button graphic 201, and make the display by touching the keypad area 211. 2 Normal operation and the display panel 21 is turned on to display a picture.

Referring to FIG. 2B again, when the display 2 is working normally and the screen is displayed, the user touches the keypad area 211 to cause the display 2 to overprint the keypad map 212 on the screen displayed by the display panel 21 by the OSD technique. This keypad template 212 includes a plurality of button graphics 213 to provide control functionality for the display 2. The user can control the display 2 to operate normally or standby, switch channels, adjust the volume, or cause the display 2 to overprint the screen menu on the screen displayed on the display panel 21 by the OSD technology and operate the screen menu by touching the button icons 213. In this embodiment, the button panel icon 212 includes four button icons 213, which are sequentially connected from the top to the bottom of the power button, menu button, positive button and negative button, wherein the power button is illustrated as a circle and There is a straight line through, the menu button is shown as M, the positive button is shown as +, and the negative button is shown as -.

Referring to FIG. 2C again, when the display 2 works normally and overprints the keypad icon 212 on the displayed screen, the user makes the display 2 by touching the menu button icon in the button icon 213 of the keypad region 211. The OSD technology additionally overprints the screen menu 214 on the screen displayed on the display panel 21. This screen menu, also known as the OSD menu, is used to provide various settings for the display 2, such as brightness, contrast, chroma or white balance settings. At this time, the user can operate the screen menu 214 by touching the button icon 213 such as the positive key and the negative key icon to perform various function settings.

3 is a circuit diagram of a narrow bezel display in accordance with an embodiment of the present invention. Referring to FIG. 3 , taking the display 2 shown in FIG. 2A to FIG. 2C as an example, the display 2 includes a touch panel, which is also called a touch screen, which may be a resistive type. Various types of single or multi-touch touch panels such as Surface Acoustic Wave (SAW), capacitive, infrared scanning or infrared image sensing. The touch panel includes a display panel 21 and a touch module 22 . Among them, the display panel 21 is used to display a screen. The touch module 22 includes a touch sensor 221 and a control circuit board 222. The touch sensor 221 is used to sense whether the display panel 21 has a touch input. The control circuit board 222 is used in the touch sensor 221. When the touch panel input is sensed, the touch panel information is generated according to the sensing result thereof.

The display 2 also includes a drive board, which is also referred to as a main control board or a main board. The driving board includes a display driving module 23 and a micro controller 24, and is mounted with a software 25 supporting a touch function, and the software 25 can be an operating system or an application. The display driving module 23 is configured to receive the video data, and the video data may be the video data of the process picture that the micro controller 24 loads the firmware to perform initialization when the display 2 is powered on, or may be the micro controller when the display 2 is working normally. The video material of the user interface of the software 25 loaded and executed 24 may also include image data for the keypad icon 212 or screen menu 214 overprinted by OSD technology. Then, the display driving module 23 processes the received video data through, for example, video decoding, analog to digital conversion, image scaling, or overprinting images by OSD technology, and then transmits the image data to the display panel 21 to display a corresponding picture.

The micro controller 24 is configured to: when it is working normally and receiving the touch point information generated by the touch input sensed by the touch module 22, according to whether the currently displayed picture has the overprint button board icon 212 or the screen menu 214 Decide whether to transfer the touch point information to the software 25. If the micro controller 24 determines that the currently displayed screen does not have the overprint button panel icon 212 or the screen menu 214, the touch point information is transmitted to the software 25. The software 25 performs corresponding operations according to the touch point information (such as moving the cursor, clicking the icon provided by the software 25, performing the function of clicking the icon, etc.), and outputting the video data corresponding to the operation to the display driving module 23 to The display panel 21 is driven to display a corresponding screen. On the other hand, if the micro controller 24 determines that the currently displayed picture has the overprint button board icon 212 or the screen menu 214, it performs a corresponding operation according to the touch point information, that is, operates the button board icon 212 or the screen menu 214, and outputs The video data corresponding to the operation is displayed to the display driving module 23 to drive the display panel 21 to display the corresponding screen.

In an embodiment, when the display 2 is in standby, only the power is supplied to the touch module 22 to sense whether the display panel 21 has a touch input, and the power is supplied to the microcontroller 24 to monitor whether the touch module 22 is sensed. Touching the touch point information generated by the input, so that the micro controller 24 controls the power module (not shown) of the display 2 to supply power to other internal components when it is determined that the touch panel area 211 has a touch input. Make monitor 2 work properly. In another embodiment, when the display 2 is in standby, only the power is supplied to the touch module 22 to sense whether the display panel 21 has a touch input, and the touch module 22 senses the touch input and is the key panel area. 211 has a touch input directly controlling the power supply module to supply power to other internal components, so that the display 2 works normally, and when the display 2 is working normally, the touch point information generated by the touch input is changed by the micro controller 24, and The power module is controlled by the microcontroller 24 to perform functions such as turning on or off the display panel 21.

4 is a circuit diagram of a narrow bezel display in accordance with another embodiment of the present invention. Referring to FIG. 4, the display 3 is electrically connected to the computer 4. The display panel 3 includes a display panel 21, a touch panel 22, a display driver module 33, and a micro controller 34. The display panel 21 and the touch panel 22 of the display 3 and the display panel are the same, and are not described herein again. The computer 4 includes a motherboard 41 and a display card 42, and is equipped with a software 43 supporting a touch function. The software 43 can be an operating system or an application.

The display driver module 33 is configured to receive the video data, and the video data may be the video data of the process picture that the motherboard 41 loads the firmware to perform initialization when the computer 4 is turned on, or the motherboard 41 may be loaded when the computer 4 is working normally. The video data of the user interface of the executed software 43 may also include image data output by the microcontroller 34 for overprinting the keypad or the screen menu by OSD technology. Then, the display driver module 33 processes the received video data through, for example, video decoding, analog to digital conversion, image scaling, or overprinting images by OSD technology, and then transmits the image data to the display panel 21 to display the corresponding image.

The micro controller 34 is configured to determine whether there is an overprint button panel icon or a screen menu according to whether the currently displayed screen is in normal operation and receives the touch point information generated by the touch input sensed by the touch module 22 This touch point information is transmitted to the motherboard 41 of the computer 4. If the micro controller 34 determines that the currently displayed screen does not have an overprint keyboard icon or a screen menu, the touch point information is transmitted to the motherboard 41 of the computer 4. The software 43 loaded and executed by the motherboard 41 performs corresponding operations according to the touch point information (such as moving the cursor, clicking the icon provided by the software 43, performing the function of clicking the icon, etc.), and outputting the same through the display card 42. The corresponding video data is operated to the display driving module 33 to drive the display panel 21 to display the corresponding screen. On the other hand, if the micro controller 34 determines that the currently displayed screen has an overprint keyboard icon or a screen menu, it performs a corresponding operation according to the touch point information, that is, operates the keypad icon or the screen menu, and outputs corresponding to the operation. The video data is displayed to the display driver module 33 to drive the display panel 21 to display a corresponding screen.

FIG. 5 is a flowchart of a method for controlling a narrow bezel display according to an embodiment of the present invention. Referring to FIG. 5 , taking the display 2 shown in FIG. 3 as an example, the display 2 enters a standby state after being connected to the AC power source. At this time, the display 2 only supplies power to the touch module 22 to sense whether the display panel 21 has Touch input (step S501). The touch module 22 continuously senses whether the display panel 21 has a touch input and has a touch input for the keypad area 211 (step S502), until the touch module 22 senses that the touch panel area 211 has a touch input. The display 2 supplies power to other internal components, causes the display 2 to operate normally (step S503), and turns on the display panel 21 to display a screen (step S504).

At this time, the display driving module 23 receives the video data of the user interface of the software 25 loaded and executed by the micro controller 24, and after processing, transmits the video data to the display panel 21 to display the corresponding screen, and then the user can directly The touch operation is performed on the screen of the user interface displayed on the display panel 21. The touch module 22 will continuously sense whether the display panel 21 has a touch input (step S505), and until the touch panel input is sensed, the touch point generated by the micro controller 24 according to the touch input. The information judges whether there is a touch input to the keypad area 211 (step S506).

When the display 2 displays a screen and senses that the area other than the keypad area 211 has a touch input, the microcontroller 24 transmits the touch point information to the software 25 and the software 25 determines whether the touch input is valid. Touch input (step S507). If it is an invalid touch input, for example, the user interface of the currently displayed software 25 disables the touch operation, then returns to step S505. If it is a valid touch input, the software 25 performs a corresponding operation according to the touch point information (such as moving the cursor, clicking the icon provided by the software 25, performing the function of clicking the icon, etc.) (step S508), and returning to the step S504 outputs the video data corresponding to the operation to the display driving module 23 to drive the display panel 21 to display the corresponding screen.

When the display 2 displays a screen and senses that the keypad area 211 has a touch input, the microcontroller 24 controls the display driver module 23 to overprint the keypad map 212 on the screen displayed by the display panel 21 by the OSD technique (step S509). ). At this time, the touch module 22 continuously senses whether the display panel 21 has a touch input. If there is a touch input, the micro controller 24 determines whether the touch panel is based on the touch point information generated by the touch input. The touch input of the button icon 213 of 212 is performed (step S510). When there is a touch input but is not a touch input of the button icon 213, the micro controller 24 starts counting and determines whether the first time (for example, 4 seconds) is exceeded (step S511), and if the first time is not exceeded, the step returns. In S510, if the first time is exceeded, the display display driving module 23 stops the overprinting of the key sheet icon 212 on the screen (step S512), and then returns to step S505.

Moreover, when the screen displayed on the display 2 is overprinted with the button panel icon 212 and the touch input of the button icon 213 is displayed, the micro controller 24 determines which button icon is based on the touch point information generated by the touch input. The touch input of 213 is performed to perform a corresponding operation, and the corresponding video data is output to the display driving module 23 to drive the display panel 21 to display the corresponding screen. In this embodiment, when only the keypad icon 212 is overlaid on the screen, only the touch input of the power button and the menu button may have corresponding operations, such as the power button icon for stopping the overlay of the button on the screen. The icon 212 is switched to the standby state, and the menu button icon is used to further overprint the screen menu 214 on the screen, but is not intended to limit the present invention. For example, when the display 2 is a television set and receives video data of a television program, The short touches of the key and negative key icons can be switched to the next and previous TV program channels, respectively, and the long touches of the positive and negative key icons can be adjusted to be high and the volume is adjusted. If the button icon 213 is touched and held for a certain period of time (for example, 1.5 seconds), it is judged as a long touch, and vice versa.

In the present embodiment, when only the keypad icon 212 is overlaid on the screen, the microcontroller 24 first determines whether or not the power button icon is short-touched (step S513). If the microcontroller 24 determines that it is a short-touch power button icon, step S512 is executed to control the display driver module 23 to stop overprinting the button panel 212 on the screen and then return to step S505. If it is determined that the short-touch power button is not displayed, Then, it is judged whether or not the power button icon is long-touched (step S514). When the micro controller 24 determines that it is the long-touch power key icon, the process returns to step S501 to enter the standby state, and if it is determined that it is not the long-touch power key icon, it is next determined whether or not the menu key icon is touched (step S515). If the micro controller 24 determines that the menu button is touched, the control display module 23 superimposes the screen menu 214 on the screen displayed on the display panel 21 by the OSD technology (step S516), and if it is determined that the menu button is not touched, Then, the process returns to step S510.

When the screen displayed by the display 2 is overlaid on the screen menu 214, the touch module 22 continuously senses whether the display panel 21 has a touch input, and if there is a touch input, the micro controller 24 is further Touching the touch point information generated by the input to determine whether it is the touch input of the button icon 213, if the touch input of the button icon 213 is performed, performing a corresponding operation, and outputting the corresponding video data to the display driving module 23 The display panel 21 is driven to display a corresponding screen. In this embodiment, when the screen menu 212 is overprinted in addition to the overlay key panel icon 212, only the touch input of the positive key, the negative key, and the menu key icon may have corresponding operations on the screen menu 214, but not To limit the invention, for example, the power button icon can still be used to switch to the standby state or also to stop overprinting the screen menu 214 on the screen.

In the present embodiment, when the screen menu 212 is overprinted on the screen, the micro controller 24 first determines whether or not the positive key icon is touched (step S517). If the micro controller 24 determines that the positive key icon is touched, the operation of adding or shifting right or up is performed (step S518) and returning to step S516 to control the display driving module 23 to display the corresponding on the overprinted screen menu 214. If it is determined that the positive key icon is not touched, it is next determined whether or not the negative key icon is touched (step S519). If the micro controller 24 determines that the negative key icon is touched, the operation of reducing or shifting to the left or down is performed (step S520) and returning to step S516 to control the display driving module 23 to display the corresponding on the overprinted screen menu 214. If it is determined that the negative key icon is not touched, it is next determined whether or not the short-touch menu key icon is displayed (step S521). If the micro controller 24 determines that it is a short touch menu key icon, the operation of selecting or confirming or canceling is performed (step S522) and the process returns to step S516 to control the display driving module 23 to display the corresponding operation on the overprinted screen menu 214. If it is determined that it is not a short touch menu key icon, it is next determined whether or not the long touch menu key icon is displayed (step S523). If the micro controller 24 determines that it is a long touch menu button, the control display module 23 stops overprinting the screen menu 214 on the screen (step S525), and if it is determined that the long touch menu button is not, it indicates that there is a touch input. However, it is not the touch input of the button icon 213, so the timing is started and it is judged whether the second time (for example, 5 seconds) is exceeded (step S524). If the second time is not exceeded, the process returns to step S517, and if the second time is exceeded, the process is executed. Step S525 controls the display driver module 23 to stop overprinting the screen menu 214 on the screen and then returns to step S510.

In one embodiment, the display 3 of the computer 4 is electrically connected as shown in FIG. When the display 3 displays a screen and senses that there is a touch input in an area other than the keypad area, the micro controller 34 transmits the touch point information to the motherboard 41 of the computer 4, and is loaded and executed by the motherboard 41. The software 43 determines whether the touch input is a valid touch input (step S507). If it is an invalid touch input, it returns to step S505. If it is a valid touch input, the software 43 performs a corresponding operation according to the touch point information (step S508), and returns to step S504 to output the video data corresponding to the operation to the display driving module 33 through the display card 42 to drive. The display panel 21 displays the corresponding screen.

In summary, the present invention uses a combination of a touch module and a driving board (including a micro controller and a display driving module) to change an existing key sheet disposed on a frame of the display to be displayed on the display panel. The virtual keypad icon not only maintains the user's habit of using the keypad for providing display control functions, but also uses a narrow border or a borderless design because the display border no longer needs to be provided with a physical keypad. The border or borderless aesthetic, and can be combined with other frames with narrow borders or borderless design to display large screens, and reduce manufacturing costs.

While the present invention has been described above in terms of the preferred embodiments thereof, it is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

1. . . Wide border display

10. . . frame

11. . . Display panel

12. . . keyboard

2, 3. . . Narrow border display

20. . . frame

201. . . Button icon

twenty one. . . Display panel

211. . . Keypad area

212. . . Button board icon

213. . . Button icon

214. . . Screen menu

twenty two. . . Touch module

221. . . Touch sensor

222. . . Control board

23, 33. . . Display driver module

24, 34. . . Micro controller

25. . . software

4. . . computer

41. . . motherboard

42. . . graphics card

43. . . software

W1, W2. . . Border width

S501. . . Display standby

S502. . . Touch the keypad area?

S503. . . The monitor works normally

S504. . . Display face

S505. . . Is there a touch input?

S506. . . Touch the keypad area?

S507. . . Effective touch input?

S508. . . Perform the appropriate action

S509. . . Overprint button board icon

S510. . . Touch the button icon?

S511. . . Did the touch input exceed the first time?

S512. . . Stop overprinting button board icon

S513. . . Short touch power button icon?

S514. . . Long touch power button icon?

S515. . . Touch the menu button icon?

S516. . . Overprint screen menu

S517. . . Touch the positive button icon?

S518. . . Perform increase/right shift/upward operation

S519. . . Touch the negative button icon?

S520. . . Perform reduction/left/down operations

S521. . . Short touch menu button icon?

S522. . . Perform selection/confirm/cancel operation

S523. . . Long touch menu button icon?

S524. . . Did the touch input exceed the second time?

S525. . . Stop overprinting screen menu

1 is a schematic diagram of a conventional wide bezel display.

2A to 2C are respectively schematic views showing the use of a narrow-frame display according to an embodiment of the present invention.

3 is a circuit diagram of a narrow bezel display in accordance with an embodiment of the present invention.

4 is a circuit diagram of a narrow bezel display in accordance with another embodiment of the present invention.

FIG. 5 is a flowchart of a method for controlling a narrow bezel display according to an embodiment of the present invention.

S501. . . Display standby

S502. . . Touch the keypad area?

S503. . . The monitor works normally

S504. . . Display

S505. . . Is there a touch input?

S506. . . Touch the keypad area?

S507. . . Effective touch input?

S508. . . Perform the appropriate action

S509. . . Overprint button board icon

S510. . . Touch the button icon?

S511. . . Did the touch input exceed the first time?

S512. . . Stop overprinting button board icon

S513. . . Short touch power button icon?

S514. . . Long touch power button icon?

S515. . . Touch the menu button icon?

S516. . . Overprint screen menu

S517. . . Touch the positive button icon?

S518. . . Perform increase/right shift/upward operation

S519. . . Touch the negative button icon?

S520. . . Perform reduction/left/down operations

S521. . . Short touch menu button icon?

S522. . . Perform selection/confirm/cancel operation

S523. . . Long touch menu button icon?

S524. . . Did the touch input exceed the second time?

S525. . . Stop overprinting screen menu

Claims (7)

A control method for a display with a narrow border or a borderless display, the display includes a display panel, a touch module, a display driving module and a micro controller for sensing the display a touch input on the panel to generate a touch point information, the display drive module is configured to receive a video data and processed and transmitted to the display panel to display a screen, the micro controller is configured to receive the touch point information The control method for the narrow border or the borderless display includes:
When the display is in standby, the touch module works normally to sense whether the display panel has a touch input, and the display works normally until a touch panel input of the display panel is sensed;
When the display is working normally and the screen is displayed, if the touch module senses that the touch panel area has a touch input, the micro controller controls the display drive module to overprint a keyboard icon on the screen. The button board diagram includes a power button icon and a menu button icon;
When the display overprints the keypad icon on the screen, if the touch module senses that the keypad area has a touch input and the microcontroller determines to touch the menu button according to the touch point information As shown, the microcontroller controls the display driver module to also overprint a screen menu on the screen. The control method for a narrow-frame or borderless display according to the first aspect of the patent application, wherein the display is equipped with a software supporting a touch function, and when the display works normally and the screen is displayed, if the touch is The module senses that the display panel has a touch input in an area other than the keypad area, and the software performs a corresponding operation according to the touch point information generated by the touch module, and outputs the corresponding video data to the The display drive module. The control method for a narrow-frame or borderless display according to the first aspect of the invention, wherein the display is electrically connected to a computer, and the computer is equipped with a software supporting a touch function, if the touch module Detecting that the display panel has a touch input in an area other than the keypad area, the micro controller transmits the touch point information generated by the touch module to the computer, so that the software of the computer performs corresponding And operate the corresponding video data to the display driving module. The control method for a narrow bezel or a bezelless display according to claim 1, wherein when the display overprints the keypad on the screen, if the micro controller determines that there is no touch input After the first time or short touch of the power button icon, the micro controller controls the display driving module to stop overprinting the button graphic on the screen, if the micro controller determines to touch the power button icon , the microcontroller controls the display to stand by. The control method for a narrow bezel or a bezelless display as described in claim 1, wherein the keypad display further includes a positive key icon and a negative key icon when the display is on the screen When overprinting the screen menu, if the micro controller determines to touch the positive key icon, the micro controller controls the display driving module to display an operation of increasing or shifting right or up on the overprinted screen menu. If the micro controller determines to touch the negative key icon, the micro controller controls the display driving module to display a reduced or left shift or a downward shift on the overlaid screen menu, if the micro controller When it is determined that the menu button is short-touched, the micro controller controls the display driver module to display an operation of selecting or confirming or canceling on the overprinted screen menu. The control method for a narrow bezel or a bezelless display as described in claim 1, wherein when the display overprints the screen menu on the screen, if the micro controller determines that the touchless input exceeds one The second time or long touch of the menu button icon, the micro controller controls the display driver module to stop overprinting the screen menu on the screen. The control method for a narrow bezel or a bezelless display as described in claim 1, wherein the frame has a width of less than 10 mm and greater than or equal to 0.