Objective
QTouch® Analyzer, which is part of QTouch Composer, provides near real-time visualization of QTouch measurement data. QTouch Analyzer can be used throughout the different phases of a development cycle. Using the basic touch sensor debugging information provided by QTouch Analyzer, it is possible to analyze sensor signal and touch delta. This debugging information can be used to appropriately tune sensor parameters such as Gain, Filter Level, Detect Threshold, and global parameters such as Drift Rates.
Basic Touch Sensor Debugging Information
The basic touch sensor debugging information is categorized into Signal, Reference, and Delta.
- Signal: Raw measurement value of a channel. This value increases with touch as shown.
- Reference: Long term average measurement on a channel.
- Initial value obtained from calibration process
- (Touch) Delta: Signal - Reference
- Difference between Signal and Reference
- Delta increases with touch
Materials
Hardware Tools
| Tool | About | Purchase |
|---|---|---|
 ATmega328PB Xplained Mini
Evaluation Kit |
| |
Software Tools
| Tool | About | Installers |
Installation
Instructions |
||
|---|---|---|---|---|---|
| Windows | Linux | Mac OSX | |||
 Atmel® Studio
Integrated Development Environment |
| | | | |
Procedure
This tutorial builds on the Intro to PTC project. Make sure you've completed that before continuing with this project.
1
QTouch Start Page
Go to the QTouch Start Page by clicking on the following icon:
2
Connected Kits
The ATmega328PB Xplained Kit connected through QDebug can be seen in the Connected Kits pane.
3
Analyze Touch Data
Right click on the connected kit and select 'Analyze Touch Data.'
The QTouch Analyzer window can also be opened by clicking on the QTouch Analyzer icon:
4
Connect
In the QTouch Analyzer window, click 'Connect.'
If the project ID of this QTouch project matches an existing project, a pop-up window appears, requesting confirmation to load the layout. Click YES.
5
Verify Connection
To verify that your board is now connected, you can check the bottom left corner of the QTouch Analyzer window.
6
Signal Selection
Click on 'Signal Selection' and select Signal, Delta, and Reference for Button0.
7
Start Reading
Click on 'Start Reading.'
8
Touch Signal
Touch the sensor and observe the change in Signal and Delta.
By default, QTouch Analyzer displays the Graph View. It also provides a Tabular View for numerical visualization of touch data. You can access it by clicking on 'Tabular View.'
After completing this lab, click on 'Stop Reading.' This will prevent QTouch Analyzer from collecting touch data over a long period of time, which might slow down your computer.
Results
The kit is connected to QTouch Analyzer and displays sensor signal, delta, and reference values.