ATAVRQTOUCHX Atmel, ATAVRQTOUCHX Datasheet - Page 161

• Manufacturer Part Number: ATAVRQTOUCHX
• Description: BOARD EVAL CAPACITIVE TOUCH
• Manufacturer: Atmel
• Series: QTouch™r

Specifications of ATAVRQTOUCHX

• Sensor Type: Touch, Capacitive
• Sensing Range: 1 Slider, 1 Wheel, 2 Buttons
• Interface: USB
• Voltage - Supply: 5V, USB
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: AT90USB1287, ATxmega128A1
• Silicon Manufacturer: Atmel
• Silicon Family Name: ATxmega
• Kit Contents: Board
• Svhc: No SVHC (15-Dec-2010)
• Core Architecture: AVR
• Core Sub-architecture: AVR19
• Kit Features: One Slider, One Wheel And 2
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Sensitivity: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Figure 48 Schematic overview of QTouch on Tiny20
6.4.4
API Flow diagram for ATtiny20
For the QTouch Libraries, the timing information is provided by the Host Application by updating
the ‘time_current_ms’ variable in the Timer ISR.
The QTouch Library uses this variable to
calculate the necessary timing for Max ON Duration, Drift and Recalibration functionality. Before
using the QTouch Libraries, the Timer ISR must be configured appropriately. Also, the Timer
Interrupt is used to update the ‘time_to_measure_touch’ variable inorder to start a capacitive
touch measurement. It is recommended to call qt_measure_sensors within 100ms each time to
avoid error in QTouch Library timing.
The touch_config_tiny20.h configuration header file can be used to set the desired number of
Touch Sensors (Buttons) as well as individual sensor Threshold, Hysteresis and Recalibration
parameters. The Sensor Global Configuration parameters must be specified using the IAR Linker
define options.
Figure 49 Linker configuration options for Tiny20
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