The touchpads class implements some easier ways to work with the MCU's capacitive touch architecture. More...

#include <touchpad_driver.h>

Classes
struct	calibrationvalues_t
	Struct containing calibration thresholds for each touchpad. More...

Public Member Functions
uint32_t	read_touchpads (uint32_t tsc_readings[14])
	read_touchpads() checks if someone is touching the capacitive touch pads.

uint32_t	discern_press (uint32_t tsc_readings[14])
	discern_press() compares capacitive touch readings with the calibration values in order to discern if a key is being pressed.

void	init ()
	The init function essentially runs the read_touchpads function and places the readings into a calibration struct.

	touchpads (TSC_HandleTypeDef *htsc)

Public Attributes
TSC_IOConfigTypeDef	all_ios = {0b00000000101110111011000010111011,0,0b00000000010001000100000001000100}
	Bit mask to activate all TSC pins.

TSC_IOConfigTypeDef	io1 = {0b00000000000100010000000100010001,0,0b00000000010001000000010001000100}
	Bit mask to activate the first pin in each TSC group.

TSC_IOConfigTypeDef	io2 = {0b00000000001000100000001000100010,0,0b00000000010001000000010001000100}
	Bit mask to activate the second pin in each TSC group.

TSC_IOConfigTypeDef	io4 = {0b00000000100010000000100010001000,0,0b00000000010001000000010001000100}
	Bit mask to activate the third pin in each TSC group.

TSC_HandleTypeDef *	touch
	Touch sensor object type (defined by the HAL)

struct touchpads::calibrationvalues_t	calibration_values

Detailed Description

The touchpads class implements some easier ways to work with the MCU's capacitive touch architecture.

Constructor & Destructor Documentation

◆ touchpads()

touchpads::touchpads ( TSC_HandleTypeDef * htsc )

inline

Member Function Documentation

◆ discern_press()

uint32_t touchpads::discern_press ( uint32_t tsc_readings[14] )

discern_press() compares capacitive touch readings with the calibration values in order to discern if a key is being pressed.

This function takes the readings from the read_touchpads() function and compares them against the calibration values found during initialization in order to discern a key press.

Parameters

[in]	tsc_readings	Readings from the touchpads
[out]	readings	Bit mask showing which touchpads are being pressed

◆ init()

void touchpads::init ( )

The init function essentially runs the read_touchpads function and places the readings into a calibration struct.

◆ read_touchpads()

uint32_t touchpads::read_touchpads ( uint32_t tsc_readings[14] )

read_touchpads() checks if someone is touching the capacitive touch pads.

Reading the capacitive touchpads is a multi-step process. The capacitive touch (tsc) pins are organized into groups of four, one of which must be configured to be the sampling pin (the pin connected to the capacitor). Before any measurement, the capacitor must be discharged to ensure an accurate reading. Then, the pins must be configured - you can't read individual pins in a group, just the group, so to read all pins, each group must be configured and read three times. Once all the pins are read, we compare them with thresholds to determine if a key press is occurring.

Parameters

[in] tsc_readings Readings from the touchpads @paramou[out] key_presses Bit mask showing which touchpads are being pressed

Member Data Documentation

◆ all_ios

TSC_IOConfigTypeDef touchpads::all_ios = {0b00000000101110111011000010111011,0,0b00000000010001000100000001000100}

Bit mask to activate all TSC pins.

◆ calibration_values

struct touchpads::calibrationvalues_t touchpads::calibration_values

◆ io1

TSC_IOConfigTypeDef touchpads::io1 = {0b00000000000100010000000100010001,0,0b00000000010001000000010001000100}

Bit mask to activate the first pin in each TSC group.

◆ io2

TSC_IOConfigTypeDef touchpads::io2 = {0b00000000001000100000001000100010,0,0b00000000010001000000010001000100}

Bit mask to activate the second pin in each TSC group.

◆ io4

TSC_IOConfigTypeDef touchpads::io4 = {0b00000000100010000000100010001000,0,0b00000000010001000000010001000100}

Bit mask to activate the third pin in each TSC group.

◆ touch

TSC_HandleTypeDef* touchpads::touch

Touch sensor object type (defined by the HAL)

The documentation for this class was generated from the following files:

Core/Inc/touchpad_driver.h
Core/Src/touchpad_driver.cpp

Classes

Public Member Functions

Public Attributes