esp-idf/docs/api-reference/peripherals/touch_pad.rst

Touch sensor
===========

Overview
--------

A touch-sensor system is built on a substrate which carries electrodes and relevant connections under a protective flat surface. 
When a user touches the surface, the capacitance variation is triggered and a binary signal is generated to indicate whether the touch is valid.

ESP32 can provide up to 10 capacitive touch pads / GPIOs. The sensing pads can be arranged in different combinations, 
so that a larger area or more points can be detected. The touch pad sensing process is under the control of a hardware-implemented finite-state machine (FSM) which is initiated by software or a dedicated hardware timer.

Application Example
-------------------

Touch sensor read example: :example:`peripherals/touch_pad_read`.
Touch sensor interrupt example: :example:`peripherals/touch_pad_interrupt`.

API Reference
-------------

.. include:: /_build/inc/touch_pad.inc
driver(touch): fix bug and add more features 1. add sens_struct.h 2. add definition of RTCCNTL and RTCIO 3. modify touch pad examples 4. update example code. 5. add comments add option in menuconfig 6. fix issue that pad index 8 and 9 are mismatched 7. add touch_pad_read_filtered() api to get value filtered by iir filter 8. modify touch pad isr func 9. Make the items in perihperal.ld in the sequence of address 10. delete Kconfig for touch pad 11. add touchpad filter APIs to adjust the filter 12. add touch_pad into index.rst 13. add touch_pad in Doxyfile 14. add touch_pad.rst 2017-07-18 11:57:28 +00:00			`Touch sensor`
			`===========`

			`Overview`
			`--------`

			`A touch-sensor system is built on a substrate which carries electrodes and relevant connections under a protective flat surface.`
			`When a user touches the surface, the capacitance variation is triggered and a binary signal is generated to indicate whether the touch is valid.`

			`ESP32 can provide up to 10 capacitive touch pads / GPIOs. The sensing pads can be arranged in different combinations,`
			`so that a larger area or more points can be detected. The touch pad sensing process is under the control of a hardware-implemented finite-state machine (FSM) which is initiated by software or a dedicated hardware timer.`

			`Application Example`
			`-------------------`

			Touch sensor read example: :example:`peripherals/touch_pad_read`.
			Touch sensor interrupt example: :example:`peripherals/touch_pad_interrupt`.

			`API Reference`
			`-------------`

			`.. include:: /_build/inc/touch_pad.inc`