ATAVRQTOUCHX Atmel, ATAVRQTOUCHX Datasheet - Page 52

• 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

Number of SNS/SNSK port pairs needed
Choice of ports available for the design
Given the above requirements for the applications, the first step is to select the right library
variant required.
Step 1: Selecting the right library variant
Referring to the library selection guide, we see that there are a few variants of libraries supported
for AT91SAM3S. One library is for IAR and the other is for GNU. If we want to use IAR
Workbench, we use the library name: libsam3s-32qt-k-8rs-iar.a.
Step 2: Defining the constants / symbols in the project space
In IAR, change preprocessor options by adding the good defines:
Alternatively, you can have them defined in a separate header file.
Step3: Usage of library API’s
Now, you can use the touch API’s to create, initialize and perform touch sensing.
5.6.10.2.3 Checklist of items for integrating QTouch acquisition method libraries
The following is a checklist of items which needs to be ensured when integrating QTouch
acquisition method libraries
52
_TOUCH_ARM_
_QTOUCH_
SNS1=B
SNSK1=B
SNS2=A
SNSK2=A
QT_NUM_CHANNELS=32
_ROTOR_SLIDER_
QT_DELAY_CYCLES=10
_SNS1_SNSK1_SAME_PORT_
_SNS2_SNSK2_SAME_PORT_
The clock prescaler register (e.g. CLKPR, XDIV) needs to be configured correctly based
on the device selected. Some devices have clock frequency selection based on fuses. It
has to be ensured the fuses are set correctly in such cases.
It is recommended to disable PULL-UP resistor on all port pins used for touch sensing on
the device selected (e.g. PUD bit in MCUCR, SFIOR for a few of the tinyAVR and
megaAVR devices Please refer to the Data sheet of the selected device).
2 pairs
SNS/SNSK
Pair1 port
SNS/SNSK
Pair 2 port
SNS1 Port: A
SNSK1 Port: A
SNS2 Port: B
SNSK2 Port: B
frequency of 48Mhz
This is determined based
on the free PIO of the
board
The choice of ports for
the port pairs is limited
and can be found in the
section 5.7.1.5
8207J-AT42-02/11