Seeed Grove-Q Touch Sensor User manual

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Grove-Q Touch Sensor
Version：1.0
Release date：9/20/2015
Wiki: http://www.seeedstudio.com/wiki/Grove_-_Q_Touch_Sensor
Bazaar: http://www.seeedstudio.com/depot/GroveQ-Touch-Sensor-p-1854.html

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Document Revision History
Revision
Date
Author
Description
1.0
Sep 21, 2015
Victor.He
Create file

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Contents
Document Revision History···································································································2
1. Introduction ···················································································································2
2. Specification···················································································································3
3. Interface function···········································································································4
4. Usage······························································································································5
4.1 Hardware Connections······································································································ 5
5. Software Part ·················································································································6
6. Resource·························································································································9

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Disclaimer
For physical injuries and possessions loss caused by those reasons which are not related to product quality,
such as operating without following manual guide, natural disasters or force majeure, we take no
responsibility for that.
Under the supervision of Seeed Technology Inc., this manual has been compiled and published which
covered the latest product description and specification. The content of this manual is subject to change
without notice.
Copyright
The design of this product (including software) and its accessories is under tutelage of laws. Any action to
violate relevant right of our product will be penalized through law. Please consciously observe relevant local
laws in the use of this product.

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1. Introduction
The Q Touch Sensor is a high sensitivity and high noise immunity touch input device. It is based on Atmel
AT42QT1070. The AT42QT1070 modulates its bursts in a spread-spectrum fashion in order to heavily
suppress the effects of external noise, and to suppress RF emissions. The QT1070 uses a dual-pulse method
of acquisition. This provides greater noise immunity and eliminates the need for external sampling
capacitors, allowing touch sensing using a single pin.

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2. Specification
Operating Voltage:
3 ~ 5.5V
Operating Current
1mA for 3.3V operating voltage
Touch Keys
7 Keys ; key0, key1, key2 are on the Grove PCB bottom side
Communicating Protocol
I2C
I2C Address
0x1B

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3. Interface function
①：On board touch key0
②：On board touch key1
③：On board touch key2
④：Touch key0 ~ key6 break out
The recommended range for key capacitance Cx is 1 pF –30 pF. Larger values of Cx will give reduced
sensitivity.
⑤：GND
⑥：Grove interface

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4. Usage
Demo: Who touched my lychee?
Have you ever heard of a lychee? Yes, it's a very famous fruit of south of China. If you have ever tasted, will
love it.
Now let's begin our demo. When you touch the hit pan (lychee), the LED will turn on.
4.1 Hardware Connections
1. Connect the I2C of Grove-Q Touch Sensor to the I2C socket on the Grove Base Shield.
2. Connect the Grove-LED to D3 (Digital Pin 3) on the Grove Base Shield.
3. Connect Key0 (marked K0) on the Grove-Q Touch sensor to a Lychee (Alternatively, you could touch
the open end of the cable with a finger while testing).

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5. Software Part
1) Download the library [Q Touch Library];
2) Unzip it into the libraries folder of Arduino IDE, for example the path could be ..\arduino-
1.0.5\libraries.
Example 1:
a) Open the example via Arduino Menu 'File -> Examples -> Seeed_QTouch-master -> isTouch'.
b) Upload the code. Note that you should select the correct board type and COM port.
c) On touching the Lychee, the LED would glow, as can be seen below.

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Example 2:
a) Open the example via Arduino Menu 'File > Examples > Seeed_QTouch-master ->
Grove_QTouch_demoCode....’
b) Upload the code.
c) Open the Serial Monitor.
d) Touch and release theLychee; The Serial Monitor woulddisplay the duration of touch asin the screenshot
below.
Example 3:
a) Open the example via Arduino Menu File > Examples > Seeed_QTouch-master > getTouchNumber
b) Upload the code.
c) Open the Serial Monitor.
d) On touching the Lychee, the Serial Monitor would display the Key that is connected, as in the screenshot
below. One can connect the fruit to any other Key and verify.

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6. Resource
Q Touch Library
Schematic pdf
Eagle file
AT42QT107 datasheet
How to detect finger touch?