QEI hardware interface class Requires mbed hardware modification: connect encoder PhA to p1.20, and PhB to p1.23. More...

#include <qeihw.h>

Public Member Functions
	QEIHW (uint32_t _dirinv, uint32_t _sigmode, uint32_t _capmode, uint32_t _invinx)
	Create a QEI object and configure it.
void	Reset (uint32_t ulResetType)
	Resets value for each type of QEI value, such as velocity, position, etc.
void	DeInit ()
	Powers down the QEI block, returns pins to GPIO mode.
FlagStatus	Direction ()
	Report direction (QEISTAT bit DIR)
uint32_t	GetPosition ()
	Get current position value in QEI peripheral.
void	SetMaxPosition (uint32_t ulMaxPos)
	Set max position value for QEI peripheral.
void	SetPositionComp (uint8_t bPosCompCh, uint32_t ulPosComp)
	Set position compare value for QEI peripheral.
uint32_t	GetIndex ()
	Get current index counter of QEI peripheral.
void	SetIndexComp (uint32_t ulIndexComp)
	Set value for index compare in QEI peripheral.
void	SetVelocityTimerReload (uint32_t ulReloadValue)
	Set Velocity timer reload value.
void	SetVelocityTimerReload_us (uint32_t ulReloadValue)
	Set Velocity timer reload value in microseconds.
uint32_t	GetTimer ()
	Get current timer counter in QEI peripheral.
uint32_t	GetVelocity ()
	Get current velocity pulse counter in current time period.
uint32_t	GetVelocityCap ()
	Get the most recently measured velocity of the QEI.
void	SetVelocityComp (uint32_t ulVelComp)
	Set Velocity Compare value for QEI peripheral.
void	SetDigiFilter (uint32_t ulSamplingPulse)
	Set value of sampling count for the digital filter in QEI peripheral.
FlagStatus	GetIntStatus (uint32_t ulIntType)
	Check whether if specified interrupt flag status in QEI peripheral is set or not.
void	IntCmd (uint32_t ulIntType, FunctionalState NewState)
	Enable/Disable specified interrupt in QEI peripheral.
void	IntSet (uint32_t ulIntType)
	Asserts specified interrupt in QEI peripheral.
void	IntClear (uint32_t ulIntType)
	De-asserts specified interrupt (pending) in QEI peripheral.
void	AppendISR (uint32_t ulISRType, void(*fptr)(void))
	Append interrupt handler for specific QEI interrupt source.
void	UnAppendISR (uint32_t ulISRType)
	Unappend interrupt handler for specific QEI interrupt source.
uint32_t	CalculateRPM (uint32_t ulVelCapValue, uint32_t ulPPR)
	Calculates the actual velocity in RPM passed via velocity capture value and Pulse Per Revolution (of the encoder) value parameter input.

Detailed Description

QEI hardware interface class Requires mbed hardware modification: connect encoder PhA to p1.20, and PhB to p1.23.

Example:

 // Display changes in encoder position and direction 
#include "mbed.h"
 #include "qeihw.h"

 DigitalOut led1(LED1);
 DigitalOut led3(LED3);
 QEIHW qei(QEI_DIRINV_NONE, QEI_SIGNALMODE_QUAD, QEI_CAPMODE_2X, QEI_INVINX_NONE );

 int main() {
     int32_t temp, position = 0;                      
     qei.SetDigiFilter(480UL);
     qei.SetMaxPosition(0xFFFFFFFF);
    
     while(1) {
         while(position == (temp = qei.GetPosition()) );
         position = temp;  
         printf("New position = %d.\r\n", temp);
         led1 = qei.Direction() == SET ? 1 : 0;
         led3 = !led1;
         wait(0.1);
     }
 }

Definition at line 70 of file qeihw.h.

Constructor & Destructor Documentation

QEIHW	(	uint32_t	_dirinv,
		uint32_t	_sigmode,
		uint32_t	_capmode,
		uint32_t	_invinx
	)

Create a QEI object and configure it.

Parameters:

_dirinv	Direction invert. When = 1, complements the QEICONF register DIR bit
_sigmode	Signal mode. When = 0, PhA and PhB are quadrature inputs. When = 1, PhA is direction and PhB is clock
_capmode	Capture mode. When = 0, count PhA edges only (2X mode). Whe = 1, count PhB edges also (4X mode).
_invinx	Invert index. When = 1, inverts the sense of the index signal
_dirinv	Direction invert. When = 1, complements the QEICONF register DIR bit
_sigmode	Signal mode. When = 0, PhA and PhB are quadrature inputs. When = 1, PhA is direction and PhB is clock
_capmode	Capture mode. When = 0, count PhA edges only (2X mode). Whe = 1, count PhB edges also (4X mode).
_invinx	Invert index. When = 1, inverts the sense of the index signal

Returns:: None

Definition at line 28 of file qeihw.cpp.

Member Function Documentation

void AppendISR	(	uint32_t	ulISRType,
		void(*)(void)	fptr
	)

Append interrupt handler for specific QEI interrupt source.

Parameters:

[in]

ulISRType

Interrupt Flag Status type, should be:

QEI_INTFLAG_INX_Int: index pulse was detected interrupt
QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
QEI_INTFLAG_DIR_Int: Change of direction interrupt
QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the current position interrupt
QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the current position interrupt
QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the current position interrupt
QEI_INTFLAG_REV_Int: Index compare value is equal to the current index count interrupt
QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt

Returns:: none

Definition at line 507 of file qeihw.cpp.

uint32_t CalculateRPM	(	uint32_t	ulVelCapValue,
		uint32_t	ulPPR
	)

Calculates the actual velocity in RPM passed via velocity capture value and Pulse Per Revolution (of the encoder) value parameter input.

Parameters:

[in]	ulVelCapValue	Velocity capture input value that can be got from QEI_GetVelocityCap() function
[in]	ulPPR	Pulse per round of encoder

Returns:: The actual value of velocity in RPM (Revolutions per minute)

Definition at line 438 of file qeihw.cpp.

void DeInit ( )

Powers down the QEI block, returns pins to GPIO mode.

De-initializes the QEI peripheral registers to their default reset values.

Returns:: None

Definition at line 110 of file qeihw.cpp.

FlagStatus Direction ( )

Report direction (QEISTAT bit DIR)

Returns:: State of the DIR bit (SET or RESET)

Definition at line 134 of file qeihw.cpp.

uint32_t GetIndex ( )

Get current index counter of QEI peripheral.

Returns:: Current value of QEI index counter

Definition at line 183 of file qeihw.cpp.

FlagStatus GetIntStatus ( uint32_t ulIntType )

Check whether if specified interrupt flag status in QEI peripheral is set or not.

Parameters:

[in]

ulIntType

Interrupt Flag Status type, should be:

QEI_INTFLAG_INX_Int: index pulse was detected interrupt
QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
QEI_INTFLAG_DIR_Int: Change of direction interrupt
QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the current position interrupt
QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the current position interrupt
QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the current position interrupt
QEI_INTFLAG_REV_Int: Index compare value is equal to the current index count interrupt
QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt

Returns:: New State of specified interrupt flag status (SET or RESET)

Definition at line 332 of file qeihw.cpp.

uint32_t GetPosition ( )

Get current position value in QEI peripheral.

Returns:: Current position value of QEI peripheral

Definition at line 144 of file qeihw.cpp.

uint32_t GetTimer ( )

Get current timer counter in QEI peripheral.

Returns:: Current timer counter in QEI peripheral

Definition at line 258 of file qeihw.cpp.

uint32_t GetVelocity ( )

Get current velocity pulse counter in current time period.

Returns:: Current velocity pulse counter value

Definition at line 268 of file qeihw.cpp.

uint32_t GetVelocityCap ( )

Get the most recently measured velocity of the QEI.

Get the most recently captured velocity of the QEI.

When the Velocity timer in QEI is over-flow, the current velocity value will be loaded into Velocity Capture register.

Returns:: The most recently measured velocity value

Definition at line 280 of file qeihw.cpp.

void IntClear ( uint32_t ulIntType )

De-asserts specified interrupt (pending) in QEI peripheral.

De-assert specified interrupt (pending) in QEI peripheral.

Parameters:

[in]

ulIntType

Interrupt Flag Status type, should be:

QEI_INTFLAG_INX_Int: index pulse was detected interrupt
QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
QEI_INTFLAG_DIR_Int: Change of direction interrupt
QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the current position interrupt
QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the current position interrupt
QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the current position interrupt
QEI_INTFLAG_REV_Int: Index compare value is equal to the current index count interrupt
QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt

Returns:: None

Definition at line 423 of file qeihw.cpp.

void IntCmd	(	uint32_t	ulIntType,
		FunctionalState	NewState
	)

Enable/Disable specified interrupt in QEI peripheral.

Parameters:

[in]

ulIntType

Interrupt Flag Status type, should be:

QEI_INTFLAG_INX_Int: index pulse was detected interrupt
QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
QEI_INTFLAG_DIR_Int: Change of direction interrupt
QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the current position interrupt
QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the current position interrupt
QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the current position interrupt
QEI_INTFLAG_REV_Int: Index compare value is equal to the current index count interrupt
QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt

[in]

NewState

New function state, should be:

DISABLE
ENABLE

Returns:: None

Definition at line 363 of file qeihw.cpp.

void IntSet ( uint32_t ulIntType )

Asserts specified interrupt in QEI peripheral.

Assert specified interrupt in QEI peripheral.

Parameters:

[in]

ulIntType

Interrupt Flag Status type, should be:

QEI_INTFLAG_INX_Int: index pulse was detected interrupt
QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
QEI_INTFLAG_DIR_Int: Change of direction interrupt
QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the current position interrupt
QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the current position interrupt
QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the current position interrupt
QEI_INTFLAG_REV_Int: Index compare value is equal to the current index count interrupt
QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt

Returns:: None

Definition at line 395 of file qeihw.cpp.

void Reset ( uint32_t ulResetType )

Resets value for each type of QEI value, such as velocity, position, etc.

Resets value for each type of QEI value, such as velocity, counter, position, etc.

Parameters:

[in]

ulResetType

QEI Reset Type, should be one of the following:

QEI_RESET_POS: Reset Position Counter
QEI_RESET_POSOnIDX: Reset Position Counter on Index signal
QEI_RESET_VEL: Reset Velocity
QEI_RESET_IDX: Reset Index Counter

[in]

ulResetType

QEI Reset Type, should be one of the following:

QEI_RESET_POS: Reset Position Counter
QEI_RESET_POSOnIDX: Reset Position Counter on Index signal
QEI_RESET_VEL: Reset Velocity
QEI_RESET_IDX: Reset Index Counter

Returns:: None

Definition at line 99 of file qeihw.cpp.

void SetDigiFilter ( uint32_t ulSamplingPulse )

Set value of sampling count for the digital filter in QEI peripheral.

Parameters:

[in] ulSamplingPulse Value of sampling count to set

Returns:: None

Definition at line 303 of file qeihw.cpp.

void SetIndexComp ( uint32_t ulIndexComp )

Set value for index compare in QEI peripheral.

Parameters:

[in] ulIndexComp Compare Index Value to set

Returns:: None

Definition at line 193 of file qeihw.cpp.

void SetMaxPosition ( uint32_t ulMaxPos )

Set max position value for QEI peripheral.

Parameters:

[in] ulMaxPos Max position value to set

Returns:: None

Definition at line 155 of file qeihw.cpp.

void SetPositionComp	(	uint8_t	bPosCompCh,
		uint32_t	ulPosComp
	)

Set position compare value for QEI peripheral.

Parameters:

[in]

bPosCompCh

Compare Position channel, should be:

QEI_COMPPOS_CH_0: QEI compare position channel 0
QEI_COMPPOS_CH_1: QEI compare position channel 1
QEI_COMPPOS_CH_2: QEI compare position channel 2

[in] ulPosComp Compare Position value to set

Returns:: None

Parameters:

[in] QEIx QEI peripheral, should be LPC_QEI

[in]

bPosCompCh

Compare Position channel, should be:

QEI_COMPPOS_CH_0: QEI compare position channel 0
QEI_COMPPOS_CH_1: QEI compare position channel 1
QEI_COMPPOS_CH_2: QEI compare position channel 2

[in] ulPosComp Compare Position value to set

Returns:: None

Definition at line 170 of file qeihw.cpp.

void SetVelocityComp ( uint32_t ulVelComp )

Set Velocity Compare value for QEI peripheral.

Parameters:

[in] ulVelComp Compare Velocity value to set

Returns:: None

Definition at line 291 of file qeihw.cpp.

void SetVelocityTimerReload ( uint32_t ulReloadValue )

Set Velocity timer reload value.

Parameters:

[in] ulReloadValue Velocity timer reload count

Returns:: None

Definition at line 204 of file qeihw.cpp.

void SetVelocityTimerReload_us ( uint32_t ulReloadValue )

Set Velocity timer reload value in microseconds.

Parameters:

[in] ulReloadValue Velocity timer reload count

Returns:: None

Definition at line 215 of file qeihw.cpp.

void UnAppendISR ( uint32_t ulISRType )

Unappend interrupt handler for specific QEI interrupt source.

Parameters:

[in]

ulISRType

Interrupt Flag Status type, should be:

QEI_INTFLAG_INX_Int: index pulse was detected interrupt
QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
QEI_INTFLAG_DIR_Int: Change of direction interrupt
QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the current position interrupt
QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the current position interrupt
QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the current position interrupt
QEI_INTFLAG_REV_Int: Index compare value is equal to the current index count interrupt
QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt

Returns:: none

Definition at line 543 of file qeihw.cpp.

Type:	Library
Created:	11 Dec 2010
Imports:	511
Forks:	2
Commits:	3
Dependents:	8
Dependencies:	0
Followers:	12

Important changes to repositories hosted on mbed.com

QEIHW Class Reference

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Repository toolbox

Repository details

Important Information for this Arm website

Important changes to repositories hosted on mbed.com

QEIHW Class Reference

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Repository toolbox

Repository details

Important Information for this Arm website

Access Warning