touch.c File Reference

This file contains the SAMD QTouch library initialization, sensor configuration and measurement routines.

• Userguide: QTouch Library Peripheral Touch Controller User Guide.
• Support: https://www.microchip.com/support/

Copyright (c) 2014-2018 Microchip Technology Inc. and its subsidiaries.

#include <asf.h>
#include "touch_api_SAMD.h"

Macros
#define	DEF_SELFCAP_CAL_SEQ1_COUNT   8
	Includes for Touch Library. More...
#define	DEF_SELFCAP_CAL_SEQ2_COUNT   4
#define	DEF_SELFCAP_CC_CAL_CLK_PRESCALE   PRSC_DIV_SEL_8
#define	DEF_SELFCAP_CC_CAL_SENSE_RESISTOR   RSEL_VAL_100
#define	DEF_SELFCAP_QUICK_REBURST_ENABLE   1u
#define	PTC_APBC_BITMASK   (1u << 19u)

Functions
void	touch_configure_ptc_clock (void)
	Initialize and enable PTC clock. More...
void	touch_selfcap_measure_complete_callback (void)
	Self Cap measure complete callback function example prototype. More...
static touch_ret_t	touch_sensors_config (void)
	configure keys, rotors and sliders. More...
touch_ret_t	touch_sensors_init (void)
	Example application entry function. More...
touch_ret_t	touch_sensors_measure (void)
	This API is used to perform a Single Capacitance measurement using the Touch Library. More...

Variables
touch_measure_data_t *	p_mutlcap_measure_data = NULL
	Mutual Cap sensors measured data pointer. More...
touch_measure_data_t *	p_selfcap_measure_data = NULL
	Self Cap sensors measured data pointer. More...
static touch_selfcap_config_t	selfcap_config
	Self Cap Configuration structure provided as input to Touch Library. More...
static uint8_t	selfcap_data_blk [PRIV_SELFCAP_DATA_BLK_SIZE]
	Self Cap sensors data block provided as input to Touch library. More...
freq_hop_sel_t	selfcap_freq_hops [3u] = {DEF_SELFCAP_HOP_FREQS}
gain_t	selfcap_gain_per_node [DEF_SELFCAP_NUM_CHANNELS] = {DEF_SELFCAP_GAIN_PER_NODE}
uint16_t	selfcap_y_nodes [DEF_SELFCAP_NUM_CHANNELS] = {DEF_SELFCAP_LINES}
	Self Cap sensors Pins Info. More...
touch_config_t	touch_config
	Touch Library input configuration structure. More...
touch_time_t	touch_time

#define DEF_SELFCAP_CAL_SEQ1_COUNT   8

Includes for Touch Library.

#define DEF_SELFCAP_CAL_SEQ2_COUNT   4

#define DEF_SELFCAP_CC_CAL_CLK_PRESCALE   PRSC_DIV_SEL_8

#define DEF_SELFCAP_CC_CAL_SENSE_RESISTOR   RSEL_VAL_100

#define DEF_SELFCAP_QUICK_REBURST_ENABLE   1u

#define PTC_APBC_BITMASK   (1u << 19u)

Referenced by touch_configure_ptc_clock().

void touch_configure_ptc_clock

(

void

)

Initialize and enable PTC clock.

References GCLK_GENERATOR_1, PTC_APBC_BITMASK, system_gclk_chan_config::source_generator, system_apb_clock_set_mask(), SYSTEM_CLOCK_APB_APBC, system_gclk_chan_enable(), system_gclk_chan_get_config_defaults(), and system_gclk_chan_set_config().

Referenced by touch_sensors_init().

void touch_selfcap_measure_complete_callback

(

void

)

Self Cap measure complete callback function example prototype.

Self Cap measure complete callback function.

This function is called by the library when the touch measurement process for Self Cap sensors is completed.

Parameters

p_measure_data

Base address of touch_measure_data_t instance.

Note

A touch_selfcap_measure_complete_callback() call signifies that fresh values of touch status, rotor/slider position, measured signals, references and Sensor data is available. The Self Cap measured data can be accessed using the p_measure_data pointer.

References tag_touch_measure_data_t::acq_status, tag_touch_measure_data_t::measurement_done_touch, TOUCH_BURST_AGAIN, TOUCH_CHANNEL_REF_CHANGE, TOUCH_ROTOR_SLIDER_POS_CHANGE, and TOUCH_STATUS_CHANGE.

Referenced by touch_sensors_measure().

touch_ret_t touch_sensors_config ( void  )

static

configure keys, rotors and sliders.

Example configuration for touch keys, rotors and sliders.

Return values

TOUCH_SUCCESS	Configuration setting successful.
TOUCH_INVALID_xx	Invalid input configuration setting.

References CHANNEL_0, CHANNEL_1, CHANNEL_2, CHANNEL_4, CHANNEL_5, CHANNEL_7, HYST_6_25, NO_AKS_GROUP, RES_8_BIT, SENSOR_TYPE_KEY, SENSOR_TYPE_ROTOR, SENSOR_TYPE_SLIDER, touch_selfcap_sensor_config(), and TOUCH_SUCCESS.

Referenced by touch_sensors_init().

touch_selfcap_config_t selfcap_config

static

Self Cap Configuration structure provided as input to Touch Library.

Note: Use the touch.h configuration header file to fill in the elements of this structure. DO NOT modify any of the input values directly in this structure.

uint8_t selfcap_data_blk[PRIV_SELFCAP_DATA_BLK_SIZE]

static

Self Cap sensors data block provided as input to Touch library.

freq_hop_sel_t selfcap_freq_hops[3u] = {DEF_SELFCAP_HOP_FREQS}

gain_t selfcap_gain_per_node[DEF_SELFCAP_NUM_CHANNELS] = {DEF_SELFCAP_GAIN_PER_NODE}

uint16_t selfcap_y_nodes[DEF_SELFCAP_NUM_CHANNELS] = {DEF_SELFCAP_LINES}

Self Cap sensors Pins Info.

touch_config_t touch_config

Initial value:

= {
    NULL,
    &selfcap_config,                
    DEF_TOUCH_PTC_ISR_LVL,          
}

Touch Library input configuration structure.