Interfacing with a touchscreen - Revision history

JakeWare at 15:10, 9 October 2009

2009-10-09T15:10:10Z

Lynch: /* Experimental Notes */

2009-02-16T07:26:01Z

Experimental Notes

← Older revision		Revision as of 02:26, 16 February 2009
Line 157:		Line 157:

	The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit, might also work.[http://computer.howstuffworks.com/question716.htm]		The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit, might also work.[http://computer.howstuffworks.com/question716.htm]
	'''Bold text'''

Lynch at 07:25, 16 February 2009

2009-02-16T07:25:15Z

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 == Overview ==
 [[image:touchscreen|thumb|200px|How a touchscreen works [http://www.touchscreenguide.com/]|right]]
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 The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen.  The relative difference in charge from each of the corners of the screen is calculated and a location is the output.  We suspect that other materials that can draw current, such as a piece of fruit, might also work.[http://computer.howstuffworks.com/question716.htm]

Chris Chow: /* Experimental Notes */

2009-02-12T18:27:26Z

Experimental Notes

← Older revision		Revision as of 13:27, 12 February 2009
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	When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.		When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.

	The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit might also work.[http://computer.howstuffworks.com/question716.htm]		The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit, might also work.[http://computer.howstuffworks.com/question716.htm]

Chris Chow: /* Overview */

2009-02-12T18:19:58Z

Overview

← Older revision		Revision as of 13:19, 12 February 2009
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	Advantages of the touchscreen are high touch resolution, high image clarity, and is not affected by dirt, grease, or moisture. However it can only be activated by the touch of something conductive, such as one's finger. [http://www.touchscreens.com/intro-touchtypes-capacitive.html]		Advantages of the touchscreen are high touch resolution, high image clarity, and is not affected by dirt, grease, or moisture. However it can only be activated by the touch of something conductive, such as one's finger. [http://www.touchscreens.com/intro-touchtypes-capacitive.html]

	On this page you will find the steps to implement the touchscreen interface on your own. This includes the code, circuit diagram, and other notes about creating the interface. If you build the circuit as displayed below and run the program through the PIC, you should be able to ~~track~~ a finger ~~along the~~ ~~surface~~ of the touchscreen.		On this page you will find the steps to implement the touchscreen interface on your own. This includes the code, circuit diagram, and other notes about creating the interface. If you build the circuit as displayed below and run the program through the PIC, you should be able to display on an LCD a finger's X-Y position on the touchscreen.
	<br><br><br><br><br>		<br><br><br><br><br>

Chris Chow: /* Overview */

2009-02-12T06:39:02Z

Overview

← Older revision		Revision as of 01:39, 12 February 2009
Line 15:		Line 15:
	Advantages of the touchscreen are high touch resolution, high image clarity, and is not affected by dirt, grease, or moisture. However it can only be activated by the touch of something conductive, such as one's finger. [http://www.touchscreens.com/intro-touchtypes-capacitive.html]		Advantages of the touchscreen are high touch resolution, high image clarity, and is not affected by dirt, grease, or moisture. However it can only be activated by the touch of something conductive, such as one's finger. [http://www.touchscreens.com/intro-touchtypes-capacitive.html]

	On this page you will find the steps to implement the touchscreen interface on your own. This includes the code, circuit diagram, and other notes about creating the interface. If you build the circuit as displayed below and ~~use~~ the ~~code~~ ~~provided~~, you should be able to track a finger along the surface of the touchscreen.		On this page you will find the steps to implement the touchscreen interface on your own. This includes the code, circuit diagram, and other notes about creating the interface. If you build the circuit as displayed below and run the program through the PIC, you should be able to track a finger along the surface of the touchscreen.
	<br><br><br><br><br>		<br><br><br><br><br>

Chris Chow: /* Overview */

2009-02-12T06:36:43Z

Overview

← Older revision		Revision as of 01:36, 12 February 2009
Line 15:		Line 15:
	Advantages of the touchscreen are high touch resolution, high image clarity, and is not affected by dirt, grease, or moisture. However it can only be activated by the touch of something conductive, such as one's finger. [http://www.touchscreens.com/intro-touchtypes-capacitive.html]		Advantages of the touchscreen are high touch resolution, high image clarity, and is not affected by dirt, grease, or moisture. However it can only be activated by the touch of something conductive, such as one's finger. [http://www.touchscreens.com/intro-touchtypes-capacitive.html]

	On this page you will find the steps to implement the touchscreen interface on your own. This includes the code, circuit diagram, and other notes about creating the interface.		On this page you will find the steps to implement the touchscreen interface on your own. This includes the code, circuit diagram, and other notes about creating the interface. If you build the circuit as displayed below and use the code provided, you should be able to track a finger along the surface of the touchscreen.
	<br><br><br><br><br>		<br><br><br><br><br>

Chris Chow: /* Experimental Notes */

2009-02-12T06:35:04Z

Experimental Notes

← Older revision		Revision as of 01:35, 12 February 2009
Line 163:		Line 163:
	When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.		When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.

	The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit might also work.http://computer.howstuffworks.com/question716.htm		The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit might also work.[http://computer.howstuffworks.com/question716.htm]

Chris Chow: /* Experimental Notes */

2009-02-12T06:34:30Z

Experimental Notes

← Older revision		Revision as of 01:34, 12 February 2009
Line 163:		Line 163:
	When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.		When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.

	The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit might also work.		The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit might also work.http://computer.howstuffworks.com/question716.htm

Chris Chow: /* Experimental Notes */

2009-02-12T06:34:16Z

Experimental Notes

← Older revision		Revision as of 01:34, 12 February 2009
Line 163:		Line 163:
	When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.		When two fingers touch the screen at the same time, the output is the average of the two sets of coordinates. For example, if a finger is placed at X:0 Y:0 and another is placed on X: 16000 Y: 16000, the output is X: 8000 Y: 8000. We see the same behavior as we put more fingers on the screen at different locations; the output is the average of all the location coordinates. This can even be seen if only one finger is touching it; depending on how much of the finger is touching the screen, the output changes to get the center of the contact point.

	The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. We suspect that other materials that can draw current, such as a piece of fruit might also work.		The reason why a finger works with the touchscreen is that the finger exhibits capacitive qualities. The human body has charge that can draw current from the touchscreen. When someone touches the screen some of the charge on the surface is transferred to the person creating a drop in the charge on the screen. The relative difference in charge from each of the corners of the screen is calculated and a location is the output. We suspect that other materials that can draw current, such as a piece of fruit might also work.