Objective
Using QTouch® Analyzer you will monitor the touch delta of a sensor and adjust its detect threshold.
This tutorial builds on the Intro to PTC and Analyze Touch Data Using QTouch® Analyzer projects. Make sure you've completed those before continuing with this hands-on exercise.
Materials
Hardware Tools
| Tool | About | Purchase |
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 ATmega328PB Xplained Mini
Evaluation Kit |
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Software Tools
| Tool | About | Installers |
Installation
Instructions |
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| Windows | Linux | Mac OSX | |||
 Atmel® Studio
Integrated Development Environment |
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Procedure
1
Connect to QTouch Analyzer
Perform steps 1 through 7 from the Analyze Touch Data Using QTouch® Analyzer project.
2
Tabular View
Select Tabular View and touch the 'V' in the AVR symbol (shown below) on your ATmega328PB Xplained Mini. Observe the maximum Delta shown in the Tabular View.
3
Stop Reading
In the QTouch Analyzer window, click on Stop Reading.
4
Open the QTouch Project Builder
In the Solution Explorer window, double-click on the .qtdgn file. Note that you may have named your project differently.
5
Change Button Settings
Select 'Button0' and click on the Settings icon.
In the 'Button0' settings, set detect threshold to 75.
6
Generate Project
Go to the 'Project Generation' section and click Generate Project.
7
Build and Program
Build the solution.
Program the application by clicking on the Start Without Debugging icon.
8
QTouch Analyzer
Open QTouch Analyzer.
In the QTouch Analyzer window, click ReConnect.
Click on Start Reading.
Use the 'Tabular View' to observe touch delta and state.
9
Touch the Sensor
Touch the sensor lightly (so that Delta is less than 75). You will notice that State is OFF.
Touch State will only change to ON whenever the Delta of Button0 is more than 75.
Detect threshold can be directly modified inside the touch_selfcap_sensor_config() function of the respective sensor in the touch.c file.
Results
You have learned how to configure and set the detect threshold value of a sensor.