EarthLCD ezLCD-405, Руководство пользователя

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e z L C D -­‐ 4 0 5 | 62
Rev.
© 2016 Earth Computers Tech. Inc.
1.7.5 BUTTON_STATE
Description: Changes the state of a previously defined touch button
Code: B1 hex, 177 dec
7 6 5 4 3 2 1 0
Byte 0: Command
Byte 1: Button No (0 to 63)
Byte 2: Button State
About the Button State:
The button is automatically redrawn after its state has been changed, if the icon for the new
state has been defined by the BUTTON_DEF command. Deleting the button (Byte 2 = 0) will not
erase the button image from the screen. The ezLCD just stops reacting to the deleted button
events. Changing the button state to Non-­‐Visible (Byte 2 = 4) will also not erase the button
image from the screen. The Non-­‐Visible (Byte 2 = 4) state should mainly be used with the
BUTTON_DEF command, if we do not wish the button to be initially drawn.
See Also: BUTTON_DEF , BUTTONS_ALL_UP , BUTTONS_DELETE_ALL , TOUCH_PROTOCOL
Important: Before using this command, please read the following chapters:
·∙ Touch Screen
·∙ ezButton
·∙ cuButton
Example:
The following sequence will change the state of the Button No. 4 to the Button Down.
The button will be redrawn using Button Down Icon.
BUTTON_STATE B1 hex (Command)
4 4 dec (Button No)
2 2 dec (Button Down)
BUTTON_STATE
button_no state
0 – Delete Permanently
1 – Up
2 – Down
3 – Disabled
4 – Non-­‐Visible