JEncoderQuadrature Class Reference

reads a quadrature (incremental) encoder More...

#include <JEncoderQuadrature.h>

Inheritance diagram for JEncoderQuadrature:

Collaboration diagram for JEncoderQuadrature:

Public Member Functions
long	zeroCounter ()
	reset the counter of how far the encoder has turned
float	getVel ()
	calculates velocity in distance per second where distance was set by setdistPerCountFactor()
long	getCounter ()
	returns how far the encoder has turned from the zero position
float	getPos ()
	returns how far the encoder has turned from the zero position converted to distance
float	getDistPerCountFactor ()
	returns a conversion factor between encoder ticks and distance that can be set for the encoder
void	setDistPerCountFactor (float _factor)
	set the conversion factor between encoder ticks and distance
void	setReverse (bool _reverse)
	reverse readings of encoder
bool	hasDirection ()
	can this encoder measure direction or just speed
bool	isVelNew ()
	could be useful for only recalculating a control loop if there's new velocity data
void	run ()
	if an encoder needs to have some code called each loop (like absolute encoder polling encoder and calculating amount turned)
void	ISRA (void)
void	ISRB (void)
Public Member Functions inherited from JEncoder
virtual void	setRev (bool _rev)
	empty function for directionless encoders to override

Protected Member Functions
	JEncoderQuadrature (byte _encoderAPin, byte _encoderBPin, float _distPerCountFactor=1.0, bool _reverse=false, unsigned long _slowestIntervalMicros=100000UL)
	constructor, sets pins and settings
virtual void	setUpInterrupts (void(*_isrAPointer)(void), void(*_isrBPointer)(void))
	set up pins and interrupts
virtual void	turnOffInterrupts ()
	disable interrupts and stop monitoring encoder

Protected Attributes
byte	encoderAPin
byte	encoderBPin

Detailed Description

reads a quadrature (incremental) encoder

speed calulation is done by measuring time between 4 encoder ticks (not between every tick since encoders may not have evenly spaced ticks) velocity is set to zero if the encoder has not turned in slowestIntervalMicros

Note

don't use this class directly, use a subclass

Constructor & Destructor Documentation

JEncoderQuadrature()

JEncoderQuadrature::JEncoderQuadrature ( byte  _encoderAPin, byte  _encoderBPin, float  _distPerCountFactor = 1.0, bool  _reverse = false, unsigned long  _slowestIntervalMicros = 100000UL  )

inlineprotected

constructor, sets pins and settings

Note

Parameters

_encoderAPin	one channel of quadrature encoder
_encoderBPin	other channel of quadrature encoder
_distPerCountFactor	conversion factor for getting distance in an actual unit
_reverse	false(default)
_slowestIntervalMicros	after this many microseconds without an encoder tick velocity is set to zero.

Member Function Documentation

getCounter()

long JEncoderQuadrature::getCounter ( )

inlinevirtual

returns how far the encoder has turned from the zero position

Note

remember that variables overflow

Return values

(long)

encoder ticks

Reimplemented from JEncoder.

getDistPerCountFactor()

float JEncoderQuadrature::getDistPerCountFactor ( )

inlinevirtual

returns a conversion factor between encoder ticks and distance that can be set for the encoder

Note

default is 1.0

Return values

(float)

distPerCountFactor

Reimplemented from JEncoder.

getPos()

float JEncoderQuadrature::getPos ( )

inlinevirtual

returns how far the encoder has turned from the zero position converted to distance

Note

remember that variables overflow (counter) and that floats have limited precision

Return values

(float)

encoder ticks converted to distance

Reimplemented from JEncoder.

getVel()

float JEncoderQuadrature::getVel ( )

inlinevirtual

calculates velocity in distance per second where distance was set by setdistPerCountFactor()

Return values

(float)

velocity

Reimplemented from JEncoder.

hasDirection()

bool JEncoderQuadrature::hasDirection ( )

inlinevirtual

can this encoder measure direction or just speed

Return values

(bool)

true = can measure direction

Reimplemented from JEncoder.

ISRA()

void JEncoderQuadrature::ISRA ( void  )

inline

ISRB()

void JEncoderQuadrature::ISRB ( void  )

inline

isVelNew()

bool JEncoderQuadrature::isVelNew ( )

inlinevirtual

could be useful for only recalculating a control loop if there's new velocity data

Return values

(bool)

true if velocity has changed since this function was last called

Reimplemented from JEncoder.

run()

void JEncoderQuadrature::run ( )

inlinevirtual

if an encoder needs to have some code called each loop (like absolute encoder polling encoder and calculating amount turned)

Note

interrupt based encoders don't need this to do anything and can define an empty function

Reimplemented from JEncoder.

setDistPerCountFactor()

void JEncoderQuadrature::setDistPerCountFactor ( float  _factor )

inlinevirtual

set the conversion factor between encoder ticks and distance

Parameters

_factor

(float)

Reimplemented from JEncoder.

setReverse()

void JEncoderQuadrature::setReverse ( bool  _reverse )

inline

reverse readings of encoder

Parameters

_reverse

whether to invert sign of readings

Return values

None

setUpInterrupts()

virtual void JEncoderQuadrature::setUpInterrupts ( void(*)(void)  _isrAPointer, void(*)(void)  _isrBPointer  )

protectedvirtual

set up pins and interrupts

Parameters

_isrAPointer	global function that calls internal ISRA, to use with enableInterrupt
_isrBPointer	global function that calls internal ISRB, to use with enableInterrupt

Reimplemented in JEncoderQuadratureAttachInterrupt, and JEncoderQuadraturePinChange.

turnOffInterrupts()

virtual void JEncoderQuadrature::turnOffInterrupts ( )

protectedvirtual

disable interrupts and stop monitoring encoder

Note

use setUpInterrupts to start encoder again

Reimplemented in JEncoderQuadratureAttachInterrupt, and JEncoderQuadraturePinChange.

zeroCounter()

long JEncoderQuadrature::zeroCounter ( )

inlinevirtual

reset the counter of how far the encoder has turned

Return values

(long)

returns value of counter before it is reset

Reimplemented from JEncoder.

Member Data Documentation

encoderAPin

byte JEncoderQuadrature::encoderAPin

protected

encoderBPin

byte JEncoderQuadrature::encoderBPin

protected

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

• src/JEncoder/JEncoderQuadrature.h