EarthLCD ezLCD-405, Manual

Page: 155 / 173

e z L C D -­‐ 4 0 5 | 155
Rev.
© 2016 Earth Computers Tech. Inc.
1.7.64 TOUCH_PROTOCOL
Description: Changes the default behavior of the ezLCD touch control function
Code: B2 hex, 178 dec
7 6 5 4 3 2 1 0
Byte 0: Command
Byte 1: Protocol-­‐ 1=ezButton, 2=cuButton,
64=CalibratedXY
About the Touch Protocols :
Currently, the following touch protocols are implemented:
1. ezButton
·∙ Touch screen buttons can be defined BUTTON_DEF command.
·∙ ezLCD sends Button Down and Button Up events for the buttons defined by the
BUTTON_DEF command.
·∙ Easy protocol. Button IDs and events are coded in 1 byte.
·∙ Events are sent only once per button state change.
2. cuButton
·∙ Similar to the ezButton, however the button states are sent continuously, 5 to 20 times
per second.
3. CalibratedXY
·∙ ezLCD sends TOUCH_X and TOUCH_Y packets (X and Y coordinates), when the screen is
pressed
·∙ ezLCD sends PEN_UP packets when the touch screen is not pressed.
·∙ Multi-­‐byte packed oriented protocol.
·∙ Packets are sent continuously, 5 to 50 times per second.
Note: Upon the Power-­‐Up the ezLCD does not send any touch screen data until the proper
protocol is selected by the TOUCH_PROTOCOL command.
See Also: BUTTON_DEF , BUTTON_STATE , BUTTONS_ALL_UP , BUTTONS_DELETE_ALL
Important: Before using this command, please read the following chapters:
·∙ Touch Screen
·∙ ezButton
·∙ cuButton
·∙ CalibratedXY
Example:
TOUCH_PROTOCOL
protocol