8 PTC Touch Pin Configuration
The PTC module supports both self- and mutual-capacitance sensors. For mutual-capacitance mode, the PTC requires one X-pin to connect the X-pattern part of a mutual cap sensor and one Y-pin to connect the Y-pattern part of the mutual cap sensor. For self-capacitance mode, the PTC requires only one Y-pin to connect a touch sensor. The QTouch® library includes the touch sensor I/O configuration and other touch processing APIs to access the PTC. For more information on PTC touch design, refer to the Atmel Qtouch Library Peripheral Touch Controller User Guide.pdf.