Modular Library - Three Group Example for Atmel START QTouch Library

Last modified by Microchip on 2023/11/09 08:55

Contents

Introduction
Example Application
- Reference Materials
- Three Configurations
Procedure
- touch.h
- touch.c
Example Project Configuration
- Compiler Configuration
- Data Visualizer Flag

Introduction

The goal of this tutorial is to show you how to combine different touch configurations into a single project. As of now, this is not possible in START or Harmony 3. For example, combining a mutual-capacitance touchpad with self-capacitance buttons and a mutual-capacitance slider.

Apart from self-capacitance plus mutual-capacitance, it may not be possible to share the same drift rate, max-on-duration, frequency hop parameters, etc., due to different physical locations of the sensors, types of sensor construction, or custom application requirements. In such cases, multiple groups can be used, each having a different set of configurations.

Example Application

For ease of demonstration, all three projects in this exercise use mutual-capacitance buttons.

Reference Materials

Microchip Studio

Project Files

SAM D20 Xplained Pro Evaluation Kit

QT1 Xplained Pro Extension Kit

Three Configurations

Picture of the SAM D20 Xplained Pro and QT1 Xplained Pro boards with the three touch zones (configurations) highlighted

Procedure

Begin by creating three different projects and verify operation. Then combine as follows:

touch.h

They must all share the same DEF_TOUCH_MEASUREMENT_PERIOD_MS.
Label the parameters of each configuration by appending one, two, and three as needed.
You can copy all three configurations to any one project.

Module	touch_set1	touch_set2	touch_set3
Acquisition	DEF_SENSOR_TYPE_1	DEF_SENSOR_TYPE_2	DEF_SENSOR_TYPE_3
Acquisition	DEF_PTC_CAL_OPTION_1	DEF_PTC_CAL_OPTION_2	DEF_PTC_CAL_OPTION_3
Acquisition	DEF_PTC_INTERRUPT_PRIORITY_1	DEF_PTC_INTERRUPT_PRIORITY_2	DEF_PTC_INTERRUPT_PRIORITY_3
Acquisition	DEF_PTC_TAU_TARGET_1	DEF_PTC_TAU_TARGET_2	DEF_PTC_TAU_TARGET_3
Acquisition	DEF_PTC_CAL_AUTO_TUNE_1	DEF_PTC_CAL_AUTO_TUNE_2	DEF_PTC_CAL_AUTO_TUNE_3
Acquisition	DEF_SEL_FREQ_INIT_1	DEF_SEL_FREQ_INIT_2	DEF_SEL_FREQ_INIT_3
Acquisition	DEF_NUM_CHANNELS_1	DEF_NUM_CHANNELS_2	DEF_NUM_CHANNELS_3
Acquisition	NODE_x_PARAMS_1	NODE_x_PARAMS_2	NODE_x_PARAMS_3
Key	DEF_NUM_SENSORS_1	DEF_NUM_SENSORS_2	DEF_NUM_SENSORS_3
Key	KEY_x_PARAMS_1	KEY_x_PARAMS_2	KEY_x_PARAMS_3
Key	DEF_TOUCH_DET_INT_1	DEF_TOUCH_DET_INT_2	DEF_TOUCH_DET_INT_3
Key	DEF_ANTI_TCH_DET_INT_1	DEF_ANTI_TCH_DET_INT_2	DEF_ANTI_TCH_DET_INT_1
Key	DEF_ANTI_TCH_RECAL_THRSHLD_1	DEF_ANTI_TCH_RECAL_THRSHLD_2	DEF_ANTI_TCH_RECAL_THRSHLD_3
Key	DEF_TCH_DRIFT_RATE_1	DEF_TCH_DRIFT_RATE_2	DEF_TCH_DRIFT_RATE_3
Key	DEF_ANTI_TCH_DRIFT_RATE_1	DEF_ANTI_TCH_DRIFT_RATE_2	DEF_ANTI_TCH_DRIFT_RATE_3
Key	DEF_DRIFT_HOLD_TIME_1	DEF_DRIFT_HOLD_TIME_2	DEF_DRIFT_HOLD_TIME_3
Key	DEF_REBURST_MODE_1	DEF_REBURST_MODE_2	DEF_REBURST_MODE_3
Key	DEF_MAX_ON_DURATION_1	DEF_MAX_ON_DURATION_2	DEF_MAX_ON_DURATION_3
Frequency Hop autotune	NUM_FREQ_STEPS_1	NUM_FREQ_STEPS_2	NUM_FREQ_STEPS_3
Frequency Hop autotune	DEF_MEDIAN_FILTER_FREQUENCIES_1	DEF_MEDIAN_FILTER_FREQUENCIES_2	DEF_MEDIAN_FILTER_FREQUENCIES_3
Frequency Hop autotune	DEF_FREQ_AUTOTUNE_ENABLE_1	DEF_FREQ_AUTOTUNE_ENABLE_2	DEF_FREQ_AUTOTUNE_ENABLE_3
Frequency Hop autotune	FREQ_AUTOTUNE_MAX_VARIANCE_1	FREQ_AUTOTUNE_MAX_VARIANCE_2	FREQ_AUTOTUNE_MAX_VARIANCE_3
Frequency Hop autotune	FREQ_AUTOTUNE_COUNT_IN_1	FREQ_AUTOTUNE_COUNT_IN_2	FREQ_AUTOTUNE_COUNT_IN_3

touch.c

Define a global variable acq_set used for sequencing the three configurations.
Configuration one, two, and three arrays and structures are declared.
touch_sensors_config: all configurations are initialized.
qtm_measure_complete_callback: configuration sequencing takes place with the acquisition index acq_set.
touch_process: execution of the three configurations.

Module	touch_set1	touch_set2	touch_set3
Acquisition	ptc_qtlib_acq_gen1	ptc_qtlib_acq_gen2	ptc_qtlib_acq_gen3
Acquisition	ptc_qtlib_node_stat1	ptc_qtlib_node_stat2	ptc_qtlib_node_stat3
Acquisition	ptc_seq_node_cfg1	ptc_seq_node_cfg2	ptc_seq_node_cfg3
Acquisition	qtlib_acq_set1	qtlib_acq_set2	qtlib_acq_set3
Key	qtlib_key_grp_config_set1	qtlib_key_grp_config_set2	qtlib_key_grp_config_set3
Key	qtlib_key_grp_data_set1	qtlib_key_grp_data_set2	qtlib_key_grp_data_set3
Key	qtlib_key_data_set1	qtlib_key_data_set2	qtlib_key_data_set3
Key	qtlib_key_configs_set1	qtlib_key_configs_set2	qtlib_key_configs_set3
Key	qtlib_key_set1	qtlib_key_set2	qtlib_key_set3
Frequency Hop autotune	qtm_freq_hop_autotune_config1	qtm_freq_hop_autotune_config2	qtm_freq_hop_autotune_config3
Frequency Hop autotune	qtm_freq_hop_autotune_data1	qtm_freq_hop_autotune_data2	qtm_freq_hop_autotune_data3
Frequency Hop autotune	qtm_freq_hop_autotune_control1	qtm_freq_hop_autotune_control2	qtm_freq_hop_autotune_control3

Example Project Configuration

Compiler Configuration

Release – Production code without project debugging and Data Visualizer
Debug – Project debugging without Data Visualizer
DataVisualizer – Both project debugging and Data Visualizer enabled

Data Visualizer Flag

Flag to enable DEF_TOUCH_DATA_STREAMER_ENABLE is removed from the touch.h file and defined in the project configuration (Project/Properties/Toolchain/AVR/GNU C Compiler/Symbols for Data Visualizer Configuration).