MD_UISwitch_4017KM Class Reference

#include <MD_UISwitch.h>

Inheritance diagram for MD_UISwitch_4017KM:

Collaboration diagram for MD_UISwitch_4017KM:

Public Member Functions
Class constructor and destructor.
	MD_UISwitch_4017KM (uint8_t numKeys, uint8_t pinClk, uint8_t pinKey, uint8_t pinRst)
	~MD_UISwitch_4017KM ()
Methods for core object control.
virtual void	begin (void)
virtual keyResult_t	read (void)
Public Member Functions inherited from MD_UISwitch
	MD_UISwitch (void)
	~MD_UISwitch ()
virtual uint8_t	getKey (void)
void	setPressTime (uint16_t t)
void	setDoublePressTime (uint16_t t)
void	setLongPressTime (uint16_t t)
void	setRepeatTime (uint16_t t)
void	enableDoublePress (boolean f)
void	enableLongPress (boolean f)
void	enableRepeat (boolean f)
void	enableRepeatResult (boolean f)

Protected Member Functions
void	reset (void)
	reset the 4017 IC
void	clock (void)
	clock the 4017 IC
Protected Member Functions inherited from MD_UISwitch
keyResult_t	processFSM (bool swState, bool reset=false)
bool	debounce (bool curStatus, bool reset=false)

Protected Attributes
uint8_t	_numKeys
	total number of keys
uint8_t	_pinClk
	4017 clock pin, LOW to HIGH transition
uint8_t	_pinKey
	key switch output to Arduino, HIGH means key is pressed
uint8_t	_pinRst
	4017 reset pin (0 if not used), LOW to HIGH transition
Protected Attributes inherited from MD_UISwitch
state_fsm	_state
	the FSM current state
keyResult_t	_kPush
	storage for pushed key in FSM
uint32_t	_timeActive
	the millis() time switch was last activated
uint8_t	_enableFlags
	functions enabled/disabled
uint8_t	_RC = 0
	RC integrator value.
bool	_prevStatus
	previous 'active' status for edge detection
state_db	_RCstate
	current RC debouning state
uint16_t	_timePress
	press time in milliseconds
uint16_t	_timeDoublePress
	double press detection time in milliseconds
uint16_t	_timeLongPress
	long press time in milliseconds
uint16_t	_timeRepeat
	repeat time delay in milliseconds
uint8_t	_lastKey
	persists the last key value until a new one is detected
int16_t	_lastKeyIdx
	internal index of the last key read

Additional Inherited Members
Public Types inherited from MD_UISwitch
enum	keyResult_t {   KEY_NULL , KEY_DOWN , KEY_UP , KEY_PRESS ,   KEY_DPRESS , KEY_LONGPRESS , KEY_RPTPRESS }
Protected Types inherited from MD_UISwitch
enum	state_fsm {   S_IDLE , S_PRESS , S_PRESS2A , S_PRESS2B ,   S_PRESSL , S_REPEAT , S_WAIT }
enum	state_db { S_WAIT_START , S_DEBOUNCE , S_WAIT_RELEASE }
Static Protected Attributes inherited from MD_UISwitch
static const uint16_t	KEY_PRESS_TIME = 150
	Default key press time in milliseconds.
static const uint16_t	KEY_DPRESS_TIME = 250
	Default double press time between presses in milliseconds.
static const uint16_t	KEY_LONGPRESS_TIME = 600
	Default long press detection time in milliseconds.
static const uint16_t	KEY_REPEAT_TIME = 300
	Default time between repeats in in milliseconds.
static const uint8_t	KEY_ACTIVE_STATE = LOW
	Default key is active low - transition high to low detection.
static const uint8_t	REPEAT_RESULT_ENABLE = 3
	Internal status bit to return KS_REPEAT instead of KS_PRESS.
static const uint8_t	DPRESS_ENABLE = 2
	Internal status bit to enable double press.
static const uint8_t	LONGPRESS_ENABLE = 1
	Internal status bit to enable long press.
static const uint8_t	REPEAT_ENABLE = 0
	Internal status bit to enable repeat key.

Detailed Description

Extension class MD_UISwitch_4017KM.

Implements keyboard matrix switches implemented using 4017 decade counter (see https://arduinoplusplus.wordpress.com/2016/02/17/up-to-100-switches-with-3-digital-pins/).

Using a 4017 IC, this class implements a method for reading many open/closed switches using only three digital I/O pins (Clock, Reset and DataIn). The class will scan a key matrix that have circuits similar to that shown above. Pin numbers used are passed to the class constructor allow the code to manage the 4017 IC to determine which key has been pressed. Pins should be directly connected to the matrix without pull-up or pull-down resistors.

The class will only detect a key if there is just one key pressed. If more than one key is pressed it will pause until just one key remains pressed.

Constructor & Destructor Documentation

MD_UISwitch_4017KM()

MD_UISwitch_4017KM::MD_UISwitch_4017KM	(	uint8_t	numKeys,
		uint8_t	pinClk,
		uint8_t	pinKey,
		uint8_t	pinRst
	)

Class Constructor.

Instantiate a new instance of the class. The parameters passed are used to the hardware interface to the switch.

The class will only return a valid key if just one key is pressed. If more than one key is pressed simultaneously, all the keys are ignored until just a single key is again detected.

Parameters

numKeys	the number of keys in the 4017 matrix (rows*columns).
pinClk	pin number for the 4017 clock pin, LOW to HIGH transition.
pinRst	pin number for the 4017 reset pin (0 if not used), LOW to HIGH transition.
pinKey	pin number for the key switch output to Arduino, HIGH means key is pressed.

~MD_UISwitch_4017KM()

MD_UISwitch_4017KM::~MD_UISwitch_4017KM

(

)

Class Destructor.

Release allocated memory and does the necessary to clean up once the queue is no longer required.

Member Function Documentation

begin()

void MD_UISwitch_4017KM::begin ( void  )

virtual

Initialize the object.

Initialize the object data. This needs to be called during setup() to initialize new data for the class that cannot be done during the object creation.

Implements MD_UISwitch.

read()

MD_UISwitch::keyResult_t MD_UISwitch_4017KM::read ( void  )

virtual

Return the key pressed of the switch matrix

Return one of the keypress types depending on what has been detected. The timing for each keypress starts when the first transition of the switch from inactive to active state and is recognized by a finite state machine whose operation is directed by the timer and option values specified.

Returns

one of the keyResult_t enumerated values

Implements MD_UISwitch.

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

• src/MD_UISwitch.h
• src/MD_UISwitch.cpp