ATMEL QTouch Library is a royalty free software library (available for GCC and IAR compiler tool chains) for developing touch applications on standard AVR and SAM microcontrollers. Customers can link the library into their applications in order to provide touch sensing capability in their projects. The Library can be used to develop single chip solutions for control applications which have touch sensing capabilities, or to develop standalone touch sensing solutions which interface with other host or control devices.
Features of ATMEL QTouch Library
Capacitive touch sensing using patented charge-transfer signal acquisition for robust sensing.
Support for a wide range of 8- and 32-bit AVRs.
Support for 32-bit ARM microcontrollers.
Support for 8-bit tiny AVRs having flash of 2K bytes.
Support both QTouch and QMatrix acquisition methods and autonomous touch for UC3L.
Support up to 64 touch sense channels for generic libraries and up to 136 channels for UC3L libraries.
Flexible choice of touch sensing functionality (keys, sliders, wheels) in a variety of combinations.
Includes Adjacent Key Suppression® (AKS) technology for the unambiguous detection of key events.
Support for both IAR and GCC compiler tool chains.
A comparison of various features and parameters between QTouch Libraries for Generic 8-bit and 32-bit AVRs as well as Device Specific Libraries is provided in the table below.
| Parameter/Functionality | Generic Tiny_Mega_Xmega | Tiny 2K | Tiny20 | Tiny40 | Generic, 32-Bit AVR | UC3L | ATSAM |
|---|---|---|---|---|---|---|---|
| Technology | QTouch, QMatrix | QTouch | QTouch-ADC | QTouch-ADC | QTouch, QMatrix | QTouch, QMatrix | QTouch |
| Rotors/Sliders Support | Yes | No | No | No | Yes | Yes | Yes |
| Filter Callback | Yes | Yes | No | Yes | Yes | Yes | Yes |
| Library Status Flags | Yes | Yes | No | Yes | Yes | Yes | Yes |
| Library Signature | Yes | No | No | No | Yes | Yes | Yes |
| Calibrate Sensing | Yes | Yes | No | Yes | Yes | Yes | Yes |
| Reset Sensing | Yes | Yes | No | Yes | Yes | Yes | Yes |
| Sensor Deltas | Yes | Yes | No | Yes | Yes | Yes | Yes |
| Maximum AKS Groups | 7 | 7 | 1 | 7 | 7 | 7 | 7 |
| Maximum Channels, QT | 16 | 4 | 5 | 12 | 32 | 17 | 32 |
| Maximum Rotors/Sliders, QT | 4 | 0 | 0 | 0 | 8 | 8 | |
| Maximum Channels, QM | 64 | 0 | 0 | 0 | 64 | 64 | 0 |
| Maximum Rotors/Sliders, QM | 8 | 0 | 0 | 0 | 8 | 0 | |
| Autonomous Touch | No | No | No | No | No | Yes | No |
| Sensor Reconfiguration | Yes | Yes | No | No | Yes | Yes | Yes |
| Frequency Hopping SS Enabled | Always | If _POWER_OPTIMIZATION = 0 | Never | Never | Always | Programmable | Always |
| Delay Cycles Parameter | QT_DELAY_CLCYES | QT_DELAY_CLCYES | DEF_CHARGE_SHARE_DELAY | DEF_QT_CHARGE_SHARE_DELAY | QT_DELAY_CYCLES | xx_CHLEN, xx_SELEN | QT_DELAY_CLCYES |
| Debug Interface Enable Macro | _DEBUG_INTERFACE_ | None | NDEBUG | _DEBUG_QTOUCH_STUDIO_ | _DEBUG_INTERFACE_ | DEF_TOUCH_QDEBUG_ENABLE | _DEBUG_INTERFACE_ |
This user guide describes the content, design and use of the QTouch Libraries. This should be read in conjunction with all of the applicable documents listed below
Device datasheet for the selected ATMEL device used for touch sensing.
Data sheet for the selected evaluation board.
A library selection guide that is used for the selection of the appropriate library from the released package. Default path: C:\Program Files\Atmel\Atmel_QTouch_Libraries_5.x\Library_Selection_Guide.xls
The intended readers of this document are engineers, who use the QTouch Library on ATMEL microcontrollers to realize capacitive touch sensing solutions.
Only Burst Again Flag
QT Values: 1 to 255, QM Values: 1,2,3,4,5,10,25,50
Value: 1 to 255
Value: 3 to 255