This is a driver for the AVR XMEGA Quadrature Decoder module (QDEC).

It provides functions for enabling, disabling and configuring the QDEC module.

See Quick Start Guide for the XMEGA QDEC Driver

Modules
	Quick Start Guide(s)
	In this section you can find a list of all Quick Start guides related to the XMEGA Quadrature Decoder (QDEC).

Data Structures
struct	qdec_config

Typedefs
typedef struct qdec_config	qdec_config_t

Enumerations
enum	QDec_index_rec_state { QDEC_STATE_NO_PH0_NO_PH90 = (0x00 << 0), QDEC_STATE_NO_PH0_PH90 = (0x01 << 0), QDEC_STATE_PH0_NO_PH90 = (0x02 << 0), QDEC_STATE_PH0_PH90 = (0x03 << 0) }

Functions
void	qdec_config_disable_index_pin (qdec_config_t *config)
	Disables index line. More...

void	qdec_config_enable_freq (qdec_config_t *config, uint32_t unit)
	Defines frequency option. More...

void	qdec_config_enable_index_pin (qdec_config_t *config, bool pin_invert, enum QDec_index_rec_state state)
	Defines index line to enable the automaticaly position reset. More...

void	qdec_config_event_channel (qdec_config_t *config, uint8_t event_channel)
	Selects the event channel to use for quadrature decoder. More...

void	qdec_config_freq_event_channel (qdec_config_t *config, uint8_t event_channel)
	Selects the event channel to use for frequency quadrature decoder. More...

void	qdec_config_freq_tc (qdec_config_t config, volatile void timer)
	Selects the event channel to use for frequency quadrature decoder. More...

void	qdec_config_phase_pins (qdec_config_t config, PORT_t port, uint8_t pins_base, bool pins_invert, uint16_t filter_us)
	This function set up the needed configuration to the port, used for the quadrature decoding. More...

void	qdec_config_revolution (qdec_config_t *config, uint16_t revolution)
	Defines the revolution of quadrature decoder. More...

void	qdec_config_tc (qdec_config_t config, volatile void timer)
	Selects the event channel to use for quadrature decoder. More...

void	qdec_enabled (qdec_config_t *config)
	Loads and enables QDec system. More...

void	qdec_get_config_defaults (qdec_config_t *config)
	This function initializes the configuration structure with the identified as commonly use case. More...

bool	qdec_get_direction (qdec_config_t *config)
	Returns the direction of the quadrature decoding counter. More...

uint16_t	qdec_get_frequency (qdec_config_t *config)
	Returns the frequency of quadrature encoder. More...

uint16_t	qdec_get_position (qdec_config_t *config)
	Returns the position of quadrature encoder. More...

void	qdec_reset_position (qdec_config_t *config)
	Returns the position of quadrature encoder. More...

typedef struct qdec_config qdec_config_t

Quadrature encoder configuration structure

enum QDec_index_rec_state

Recognition states of index pin

Enumerator
QDEC_STATE_NO_PH0_NO_PH90
QDEC_STATE_NO_PH0_PH90
QDEC_STATE_PH0_NO_PH90
QDEC_STATE_PH0_PH90

void qdec_config_disable_index_pin ( qdec_config_t * config )

Disables index line.

Parameters

config Handle on a QDec configuration structure

References qdec_config::enabled, and qdec_config::index.

void qdec_config_enable_freq	(	qdec_config_t *	config,
		uint32_t	unit
	)

Defines frequency option.

This option allows to compute automaticaly through an event and timer the frequency rotation. The system will be configurated with a resolution at least as high as the one specified. The resolution of a TC is synonymous with its clock frequency.

Parameters

config	Handle on a QDec configuration structure
unit	Desired unit used by qdec_get_frequency() in mHz.

References qdec_config::enabled, qdec_config::freq_opt, and qdec_config::unit.

void qdec_config_enable_index_pin	(	qdec_config_t *	config,
		bool	pin_invert,
		enum QDec_index_rec_state	state
	)

Defines index line to enable the automaticaly position reset.

Parameters

config	Handle on a QDec configuration structure
pin_invert	True if IO pins should be inverted
state	Recognition states of index pin

References qdec_config::enabled, qdec_config::index, qdec_config::pin_invert, and qdec_config::rec_state.

void qdec_config_event_channel	(	qdec_config_t *	config,
		uint8_t	event_channel
	)

Selects the event channel to use for quadrature decoder.

Parameters

config	Handle on a QDec configuration structure
event_channel	Which event channel to use for quadrature decoder XMEGA B, E authorizes channel 0. XMEGA D authorizes channel 0, 2. XMEGA A, C authorizes channel 0, 2, 4.

References qdec_config::event_channel.

void qdec_config_freq_event_channel	(	qdec_config_t *	config,
		uint8_t	event_channel
	)

Selects the event channel to use for frequency quadrature decoder.

Parameters

config	Handle on a QDec configuration structure
event_channel	Which event channel to use for frequency QDec XMEGA B, E authorizes channel 0. XMEGA D authorizes channel 0, 2. XMEGA A, C authorizes channel 0, 2, 4. Note: If

References qdec_config::event_channel, and qdec_config::freq_opt.

void qdec_config_freq_tc	(	qdec_config_t *	config,
		volatile void *	timer
	)

Selects the event channel to use for frequency quadrature decoder.

Parameters

config	Handle on a QDec configuration structure
timer	Pointer to timer module used for frequency QDec XMEGA E authorizes &TC4 or &TC5. other XMEGA authorizes &TC0, ...

References qdec_config::freq_opt, and qdec_config::timer.

void qdec_config_phase_pins	(	qdec_config_t *	config,
		PORT_t *	port,
		uint8_t	pins_base,
		bool	pins_invert,
		uint16_t	filter_us
	)

This function set up the needed configuration to the port, used for the quadrature decoding.

Parameters

config	Handle on a QDec configuration structure
port	Pointer to PORT module, which is used for quadrature
pins_base	First pin number to be used for QDPH0 input from port pins_base+1 for QDPH90 and pins_base+2 for QDINDX
pins_invert	True if IO pins should be inverted
filter_us	Pin stable timing requested to validate level

References qdec_config::phases, qdec_config::pins_base, qdec_config::pins_filter_us, qdec_config::pins_invert, and qdec_config::port.

void qdec_config_revolution	(	qdec_config_t *	config,
		uint16_t	revolution
	)

Defines the revolution of quadrature decoder.

Parameters

config	Handle on a QDec configuration structure
revolution	Number of position for a revolution

References Assert, and qdec_config::revolution.

void qdec_config_tc	(	qdec_config_t *	config,
		volatile void *	timer
	)

Selects the event channel to use for quadrature decoder.

Parameters

config	Handle on a QDec configuration structure
timer	Pointer to timer module used for Quadrature decoding XMEGA E authorizes &TC4 or &TC5. other XMEGA authorizes &TC0, ...

References qdec_config::timer.

void qdec_enabled ( qdec_config_t * config )

Loads and enables QDec system.

Parameters

config Handle on a QDec configuration structure

References Assert, qdec_config::enabled, qdec_config::event_channel, qdec_config::freq_opt, qdec_config::port, qdec_enabled_evsys(), qdec_enabled_pins(), qdec_enabled_tc(), qdec_enabled_tc_freq(), and qdec_config::rotary.