GPIO - General-Purpose Input/Output

GPIO gives access to the MCU pins.

Data Structures
struct	gpio_map_t
	A type definition of pins and modules connectivity. More...

Peripheral Bus Interface
static uint32_t	gpio_configure_edge_detector (uint32_t pin, uint32_t mode)
	Configure the edge detector of an input pin. More...

Return Values of the GPIO API
#define	GPIO_SUCCESS   0
	Function successfully completed. More...
#define	GPIO_INVALID_ARGUMENT   1
	Input parameters are out of range. More...

Interrupt Trigger Modes
#define	GPIO_PIN_CHANGE   0
	Interrupt triggered upon pin change. More...
#define	GPIO_RISING_EDGE   1
	Interrupt triggered upon rising edge. More...
#define	GPIO_FALLING_EDGE   2
	Interrupt triggered upon falling edge. More...

Common defines for GPIO_FLAGS parameter
#define	GPIO_DIR_INPUT   (0 << 0)
	Pin is Input. More...
#define	GPIO_DIR_OUTPUT   (1 << 0)
	Pin is Output. More...
#define	GPIO_INIT_LOW   (0 << 1)
	Initial Output State is Low. More...
#define	GPIO_INIT_HIGH   (1 << 1)
	Initial Output State is High. More...
#define	GPIO_PULL_UP   (1 << 2)
	Pull-Up (when input) More...
#define	GPIO_PULL_DOWN   (2 << 2)
	Pull-Down (when input) More...
#define	GPIO_BUSKEEPER   (3 << 2)
	Bus Keeper. More...
#define	GPIO_DRIVE_MIN   (0 << 4)
	Drive Min Configuration. More...
#define	GPIO_DRIVE_LOW   (1 << 4)
	Drive Low Configuration. More...
#define	GPIO_DRIVE_HIGH   (2 << 4)
	Drive High Configuration. More...
#define	GPIO_DRIVE_MAX   (3 << 4)
	Drive Max Configuration. More...
#define	GPIO_OPEN_DRAIN   (1 << 6)
	Open-Drain (when output) More...
#define	GPIO_INTERRUPT   (1 << 7)
	Enable Pin/Group Interrupt. More...
#define	GPIO_BOTHEDGES   (3 << 7)
	Sense Both Edges. More...
#define	GPIO_RISING   (5 << 7)
	Sense Rising Edge. More...
#define	GPIO_FALLING   (7 << 7)
	Sense Falling Edge. More...

Peripheral Bus Interface
Low-speed interface with a non-deterministic number of clock cycles per access. This interface operates with lower clock frequencies (fPB <= fCPU), and its timing is not deterministic since it needs to access a shared bus which may be heavily loaded. Note This interface is immediately available without initialization.
uint32_t	gpio_enable_module (const gpio_map_t gpiomap, uint32_t size)
	Enables specific module modes for a set of pins. More...
uint32_t	gpio_enable_module_pin (uint32_t pin, uint32_t function)
	Enables a specific module mode for a pin. More...
void	gpio_enable_gpio (const gpio_map_t gpiomap, uint32_t size)
	Enables the GPIO mode of a set of pins. More...
void	gpio_enable_gpio_pin (uint32_t pin)
	Enables the GPIO mode of a pin. More...
void	gpio_enable_pin_pull_up (uint32_t pin)
	Enables the pull-up resistor of a pin. More...
void	gpio_disable_pin_pull_up (uint32_t pin)
	Disables the pull-up resistor of a pin. More...
void	gpio_configure_pin (uint32_t pin, uint32_t flags)
	Configuration functionality on a pin. More...
void	gpio_configure_group (uint32_t port, uint32_t mask, uint32_t flags)
	Configuration functionality on a port. More...
bool	gpio_get_pin_value (uint32_t pin)
	Returns the value of a pin. More...
static __always_inline bool	gpio_pin_is_low (uint32_t pin)
	Check if the pin is in low logical level. More...
static __always_inline bool	gpio_pin_is_high (uint32_t pin)
	Check if the pin is in high logical level. More...
bool	gpio_get_gpio_pin_output_value (uint32_t pin)
	Returns the output value set for a GPIO pin. More...
bool	gpio_get_gpio_open_drain_pin_output_value (uint32_t pin)
	Returns the output value set for a GPIO pin using open drain. More...
void	gpio_set_gpio_pin (uint32_t pin)
	Drives a GPIO pin to 1. More...
void	gpio_set_pin_high (uint32_t pin)
	Drives a GPIO pin to 1. More...
void	gpio_set_group_high (uint32_t port, uint32_t mask)
	Drives a GPIO port to 1. More...
void	gpio_clr_gpio_pin (uint32_t pin)
	Drives a GPIO pin to 0. More...
void	gpio_set_pin_low (uint32_t pin)
	Drives a GPIO pin to 0. More...
void	gpio_set_group_low (uint32_t port, uint32_t mask)
	Drives a GPIO port to 0. More...
void	gpio_tgl_gpio_pin (uint32_t pin)
	Toggles a GPIO pin. More...
void	gpio_toggle_pin (uint32_t pin)
	Toggles a GPIO pin. More...
void	gpio_toggle_group (uint32_t port, uint32_t mask)
	Toggles a GPIO group. More...
void	gpio_set_gpio_open_drain_pin (uint32_t pin)
	Drives a GPIO pin to 1 using open drain. More...
void	gpio_clr_gpio_open_drain_pin (uint32_t pin)
	Drives a GPIO pin to 0 using open drain. More...
void	gpio_tgl_gpio_open_drain_pin (uint32_t pin)
	Toggles a GPIO pin using open drain. More...
void	gpio_enable_pin_glitch_filter (uint32_t pin)
	Enables the glitch filter of a pin. More...
void	gpio_disable_pin_glitch_filter (uint32_t pin)
	Disables the glitch filter of a pin. More...
uint32_t	gpio_enable_pin_interrupt (uint32_t pin, uint32_t mode)
	Enables the interrupt of a pin with the specified settings. More...
void	gpio_disable_pin_interrupt (uint32_t pin)
	Disables the interrupt of a pin. More...
bool	gpio_get_pin_interrupt_flag (uint32_t pin)
	Gets the interrupt flag of a pin. More...
void	gpio_clear_pin_interrupt_flag (uint32_t pin)
	Clears the interrupt flag of a pin. More...

Local Bus Interface
High-speed interface with only one clock cycle per access. This interface operates with high clock frequency (fCPU), and its timing is deterministic since it does not need to access a shared bus which may be heavily loaded. Warning To use this interface, the clock frequency of the peripheral bus on which the GPIO peripheral is connected must be set to the CPU clock frequency (fPB = fCPU). Note This interface has to be initialized in order to be available.
static __always_inline void	gpio_local_init (void)
	Enables the local bus interface for GPIO. More...
static __always_inline void	gpio_local_enable_pin_output_driver (uint32_t pin)
	Enables the output driver of a pin. More...
static __always_inline void	gpio_local_disable_pin_output_driver (uint32_t pin)
	Disables the output driver of a pin. More...
static __always_inline bool	gpio_local_get_pin_value (uint32_t pin)
	Returns the value of a pin. More...
static __always_inline void	gpio_local_set_gpio_pin (uint32_t pin)
	Drives a GPIO pin to 1. More...
static __always_inline void	gpio_local_clr_gpio_pin (uint32_t pin)
	Drives a GPIO pin to 0. More...
static __always_inline void	gpio_local_tgl_gpio_pin (uint32_t pin)
	Toggles a GPIO pin. More...
static __always_inline void	gpio_local_init_gpio_open_drain_pin (uint32_t pin)
	Initializes the configuration of a GPIO pin so that it can be used with GPIO open-drain functions. More...
static __always_inline void	gpio_local_set_gpio_open_drain_pin (uint32_t pin)
	Drives a GPIO pin to 1 using open drain. More...
static __always_inline void	gpio_local_clr_gpio_open_drain_pin (uint32_t pin)
	Drives a GPIO pin to 0 using open drain. More...
static __always_inline void	gpio_local_tgl_gpio_open_drain_pin (uint32_t pin)
	Toggles a GPIO pin using open drain. More...

Peripheral Event System support
The GPIO can be programmed to output peripheral events whenever an interrupt condition is detected, such as pin value change, or only when a rising or falling edge is detected.
static __always_inline void	gpio_enable_pin_periph_event (uint32_t pin)
	Enables the peripheral event generation of a pin. More...
static __always_inline void	gpio_disable_pin_periph_event (uint32_t pin)
	Disables the peripheral event generation of a pin. More...
uint32_t	gpio_configure_pin_periph_event_mode (uint32_t pin, uint32_t mode, uint32_t use_igf)

#define GPIO_BOTHEDGES   (3 << 7)

Sense Both Edges.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_BUSKEEPER   (3 << 2)

Bus Keeper.

#define GPIO_DIR_INPUT   (0 << 0)

Pin is Input.

#define GPIO_DIR_OUTPUT   (1 << 0)

Pin is Output.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_DRIVE_HIGH   (2 << 4)

Drive High Configuration.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_DRIVE_LOW   (1 << 4)

Drive Low Configuration.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_DRIVE_MAX   (3 << 4)

Drive Max Configuration.

#define GPIO_DRIVE_MIN   (0 << 4)

Drive Min Configuration.

#define GPIO_FALLING   (7 << 7)

Sense Falling Edge.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_FALLING_EDGE   2

Interrupt triggered upon falling edge.

Referenced by gpio_configure_edge_detector().

#define GPIO_INIT_HIGH   (1 << 1)

Initial Output State is High.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_INIT_LOW   (0 << 1)

Initial Output State is Low.

#define GPIO_INTERRUPT   (1 << 7)

Enable Pin/Group Interrupt.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_INVALID_ARGUMENT   1

Input parameters are out of range.

Referenced by gpio_configure_edge_detector(), gpio_enable_module_pin(), and gpio_enable_pin_interrupt().

#define GPIO_OPEN_DRAIN   (1 << 6)

Open-Drain (when output)

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_PIN_CHANGE   0

Interrupt triggered upon pin change.

Referenced by gpio_configure_edge_detector().

#define GPIO_PULL_DOWN   (2 << 2)

Pull-Down (when input)

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_PULL_UP   (1 << 2)

Pull-Up (when input)

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_RISING   (5 << 7)

Sense Rising Edge.

Referenced by gpio_configure_group(), and gpio_configure_pin().

#define GPIO_RISING_EDGE   1

Interrupt triggered upon rising edge.

Referenced by gpio_configure_edge_detector().

#define GPIO_SUCCESS   0

Function successfully completed.

Referenced by gpio_configure_edge_detector(), gpio_enable_module(), gpio_enable_module_pin(), and gpio_enable_pin_interrupt().

void gpio_clear_pin_interrupt_flag

(

uint32_t

pin

)

Clears the interrupt flag of a pin.

Parameters

pin	The pin number.

void gpio_clr_gpio_open_drain_pin

(

uint32_t

pin

)

Drives a GPIO pin to 0 using open drain.

Parameters

pin	The pin number.

void gpio_clr_gpio_pin

(

uint32_t

pin

)

Drives a GPIO pin to 0.

Parameters

pin	The pin number.

static uint32_t gpio_configure_edge_detector ( uint32_t  pin, uint32_t  mode  )

static

Configure the edge detector of an input pin.

Parameters

pin	The pin number.
mode	The edge detection mode (GPIO_PIN_CHANGE, GPIO_RISING_EDGE or GPIO_FALLING_EDGE).

Returns

GPIO_SUCCESS or GPIO_INVALID_ARGUMENT.

References GPIO_FALLING_EDGE, GPIO_INVALID_ARGUMENT, GPIO_PIN_CHANGE, GPIO_RISING_EDGE, and GPIO_SUCCESS.

Referenced by gpio_enable_pin_interrupt().

void gpio_configure_group	(	uint32_t	port,
		uint32_t	mask,
		uint32_t	flags
	)

Configuration functionality on a port.

Parameters

port	The port number.
mask	The mask.
flags	The configuration.

References GPIO_BOTHEDGES, GPIO_DIR_OUTPUT, GPIO_DRIVE_HIGH, GPIO_DRIVE_LOW, GPIO_FALLING, GPIO_INIT_HIGH, GPIO_INTERRUPT, GPIO_OPEN_DRAIN, GPIO_PULL_DOWN, GPIO_PULL_UP, and GPIO_RISING.

void gpio_configure_pin	(	uint32_t	pin,
		uint32_t	flags
	)

Configuration functionality on a pin.

Parameters

pin	The pin number.
flags	The configuration.

References GPIO_BOTHEDGES, GPIO_DIR_OUTPUT, GPIO_DRIVE_HIGH, GPIO_DRIVE_LOW, GPIO_FALLING, GPIO_INIT_HIGH, GPIO_INTERRUPT, GPIO_OPEN_DRAIN, GPIO_PULL_DOWN, GPIO_PULL_UP, and GPIO_RISING.

uint32_t gpio_configure_pin_periph_event_mode	(	uint32_t	pin,
		uint32_t	mode,
		uint32_t	use_igf
	)

void gpio_disable_pin_glitch_filter

(

uint32_t

pin

)

Disables the glitch filter of a pin.

Parameters

pin	The pin number.

void gpio_disable_pin_interrupt

(

uint32_t

pin

)

Disables the interrupt of a pin.

Parameters

pin	The pin number.

static __always_inline void gpio_disable_pin_periph_event ( uint32_t  pin )

static

Disables the peripheral event generation of a pin.

Parameters

pin	The pin number.

void gpio_disable_pin_pull_up

(

uint32_t

pin

)

Disables the pull-up resistor of a pin.

Parameters

pin	The pin number.

void gpio_enable_gpio	(	const gpio_map_t	gpiomap,
		uint32_t	size
	)

Enables the GPIO mode of a set of pins.

Parameters

gpiomap	The pin map.
size	The number of pins in gpiomap.

References gpio_enable_gpio_pin(), and gpio_map_t::pin.

void gpio_enable_gpio_pin

(

uint32_t

pin

)

Enables the GPIO mode of a pin.

Parameters

pin	The pin number. Refer to the product header file `uc3x.h' (where x is the part number; e.g. x = a0512) for pin definitions. E.g., to enable the GPIO mode of PX21, AVR32_PIN_PX21 can be used. Module pins such as AVR32_PWM_3_PIN for PWM channel 3 can also be used to release module pins for GPIO.

Referenced by gpio_enable_gpio().

uint32_t gpio_enable_module	(	const gpio_map_t	gpiomap,
		uint32_t	size
	)

Enables specific module modes for a set of pins.

Parameters

gpiomap	The pin map.
size	The number of pins in gpiomap.

Returns

GPIO_SUCCESS or GPIO_INVALID_ARGUMENT.

References gpio_map_t::function, gpio_enable_module_pin(), GPIO_SUCCESS, and gpio_map_t::pin.

Referenced by main().

uint32_t gpio_enable_module_pin	(	uint32_t	pin,
		uint32_t	function
	)

Enables a specific module mode for a pin.

Note

A pin and pin function index can be found in the device part header file. The AVR32_*_PIN constants map a GPIO number from the device datasheet to the appropriate pin function, while the corresponding AVR32_*_FUNCTION macro contains the appropriate function index.

For example, the constants AVR32_PWM_3_PIN and AVR32_PWM_3_FUNCTION contain the pin and function index of the PWM module, channel 3, for the current device (if available).

Parameters

pin	The pin number.
function	The pin function.

Returns

GPIO_SUCCESS or GPIO_INVALID_ARGUMENT.

References GPIO_INVALID_ARGUMENT, and GPIO_SUCCESS.

Referenced by gpio_enable_module().

void gpio_enable_pin_glitch_filter

(

uint32_t

pin

)

Enables the glitch filter of a pin.

When the glitch filter is enabled, a glitch with duration of less than 1 clock cycle is automatically rejected, while a pulse with duration of 2 clock cycles or more is accepted. For pulse durations between 1 clock cycle and 2 clock cycles, the pulse may or may not be taken into account, depending on the precise timing of its occurrence. Thus for a pulse to be guaranteed visible it must exceed 2 clock cycles, whereas for a glitch to be reliably filtered out, its duration must not exceed 1 clock cycle. The filter introduces 2 clock cycles latency.

Parameters

pin	The pin number.

uint32_t gpio_enable_pin_interrupt	(	uint32_t	pin,
		uint32_t	mode
	)

Enables the interrupt of a pin with the specified settings.

Parameters

pin	The pin number.
mode	The trigger mode (GPIO_PIN_CHANGE, GPIO_RISING_EDGE or GPIO_FALLING_EDGE).

Returns

GPIO_SUCCESS or GPIO_INVALID_ARGUMENT.

References gpio_configure_edge_detector(), GPIO_INVALID_ARGUMENT, and GPIO_SUCCESS.

static __always_inline void gpio_enable_pin_periph_event ( uint32_t  pin )

static

Enables the peripheral event generation of a pin.

Parameters

pin	The pin number.

void gpio_enable_pin_pull_up

(

uint32_t

pin

)

Enables the pull-up resistor of a pin.

Parameters

pin	The pin number.

bool gpio_get_gpio_open_drain_pin_output_value

(

uint32_t

pin

)

Returns the output value set for a GPIO pin using open drain.

Parameters

pin	The pin number.

Returns

The pin output value.

Note

This function must be used in conjunction with gpio_set_gpio_open_drain_pin, gpio_clr_gpio_open_drain_pin and gpio_tgl_gpio_open_drain_pin.

bool gpio_get_gpio_pin_output_value

(

uint32_t

pin

)

Returns the output value set for a GPIO pin.

Parameters

pin	The pin number.

Returns

The pin output value.

Note

This function must be used in conjunction with gpio_set_gpio_pin, gpio_clr_gpio_pin and gpio_tgl_gpio_pin.

bool gpio_get_pin_interrupt_flag

(

uint32_t

pin

)

Gets the interrupt flag of a pin.

Parameters

pin	The pin number.

Returns

The pin interrupt flag.

bool gpio_get_pin_value

(

uint32_t

pin

)

Returns the value of a pin.

Parameters

pin	The pin number.

Returns

The pin value.

Referenced by gpio_pin_is_high(), and gpio_pin_is_low().

static __always_inline void gpio_local_clr_gpio_open_drain_pin ( uint32_t  pin )

static

Drives a GPIO pin to 0 using open drain.

Parameters

pin	The pin number.

Note

gpio_local_init and gpio_local_init_gpio_open_drain_pin must have been called beforehand.

This function does not enable the GPIO mode of the pin. gpio_enable_gpio_pin can be called for this purpose.

static __always_inline void gpio_local_clr_gpio_pin ( uint32_t  pin )

static

Drives a GPIO pin to 0.

Parameters

pin	The pin number.

Note

gpio_local_init must have been called beforehand.

This function does not enable the GPIO mode of the pin nor its output driver. gpio_enable_gpio_pin and gpio_local_enable_pin_output_driver can be called for this purpose.

static __always_inline void gpio_local_disable_pin_output_driver ( uint32_t  pin )

static

Disables the output driver of a pin.

Parameters

pin	The pin number.

Note

gpio_local_init must have been called beforehand.

static __always_inline void gpio_local_enable_pin_output_driver ( uint32_t  pin )

static

Enables the output driver of a pin.

Parameters

pin	The pin number.

Note

gpio_local_init must have been called beforehand.

This function does not enable the GPIO mode of the pin. gpio_enable_gpio_pin can be called for this purpose.

static __always_inline bool gpio_local_get_pin_value ( uint32_t  pin )

static

Returns the value of a pin.

Parameters

pin	The pin number.

Returns

The pin value.

Note

gpio_local_init must have been called beforehand.

static __always_inline void gpio_local_init ( void  )

static

Enables the local bus interface for GPIO.

Note

This function must have been called at least once before using other functions in this interface.

References Get_system_register, and Set_system_register.

static __always_inline void gpio_local_init_gpio_open_drain_pin ( uint32_t  pin )

static

Initializes the configuration of a GPIO pin so that it can be used with GPIO open-drain functions.

Note

This function must have been called at least once before using gpio_local_set_gpio_open_drain_pin, gpio_local_clr_gpio_open_drain_pin or gpio_local_tgl_gpio_open_drain_pin.

static __always_inline void gpio_local_set_gpio_open_drain_pin ( uint32_t  pin )

static

Drives a GPIO pin to 1 using open drain.

Parameters

pin	The pin number.

Note

gpio_local_init and gpio_local_init_gpio_open_drain_pin must have been called beforehand.

This function does not enable the GPIO mode of the pin. gpio_enable_gpio_pin can be called for this purpose.

static __always_inline void gpio_local_set_gpio_pin ( uint32_t  pin )

static

Drives a GPIO pin to 1.

Parameters

pin	The pin number.

Note

gpio_local_init must have been called beforehand.

This function does not enable the GPIO mode of the pin nor its output driver. gpio_enable_gpio_pin and gpio_local_enable_pin_output_driver can be called for this purpose.

static __always_inline void gpio_local_tgl_gpio_open_drain_pin ( uint32_t  pin )

static

Toggles a GPIO pin using open drain.

Parameters

pin	The pin number.

Note

gpio_local_init and gpio_local_init_gpio_open_drain_pin must have been called beforehand.

This function does not enable the GPIO mode of the pin. gpio_enable_gpio_pin can be called for this purpose.

static __always_inline void gpio_local_tgl_gpio_pin ( uint32_t  pin )

static

Toggles a GPIO pin.

Parameters

pin	The pin number.

Note

gpio_local_init must have been called beforehand.

This function does not enable the GPIO mode of the pin nor its output driver. gpio_enable_gpio_pin and gpio_local_enable_pin_output_driver can be called for this purpose.

static __always_inline bool gpio_pin_is_high ( uint32_t  pin )

static

Check if the pin is in high logical level.

Parameters

pin	The pin number.

Returns

bool true if the pin is in high logical level false if the pin is not in high logical level

References gpio_get_pin_value().

static __always_inline bool gpio_pin_is_low ( uint32_t  pin )

static

Check if the pin is in low logical level.

Parameters

pin	The pin number.

Returns

bool true if the pin is in low logical level false if the pin is not in low logical level

References gpio_get_pin_value().

void gpio_set_gpio_open_drain_pin

(

uint32_t

pin

)

Drives a GPIO pin to 1 using open drain.

Parameters

pin	The pin number.

void gpio_set_gpio_pin

(

uint32_t

pin

)

Drives a GPIO pin to 1.

Parameters

pin	The pin number.

void gpio_set_group_high	(	uint32_t	port,
		uint32_t	mask
	)

Drives a GPIO port to 1.

Parameters

port	The port number.
mask	The mask.

void gpio_set_group_low	(	uint32_t	port,
		uint32_t	mask
	)

Drives a GPIO port to 0.

Parameters

port	The port number.
mask	The mask.

void gpio_set_pin_high

(

uint32_t

pin

)

Drives a GPIO pin to 1.

Parameters

pin	The pin number.

Note

The function gpio_configure_pin must be called before.

void gpio_set_pin_low

(

uint32_t

pin

)

Drives a GPIO pin to 0.

Parameters

pin	The pin number.

Note

The function gpio_configure_pin must be called before.

void gpio_tgl_gpio_open_drain_pin

(

uint32_t

pin

)

Toggles a GPIO pin using open drain.

Parameters

pin	The pin number.

void gpio_tgl_gpio_pin

(

uint32_t

pin

)

Toggles a GPIO pin.

Parameters

pin	The pin number.

void gpio_toggle_group	(	uint32_t	port,
		uint32_t	mask
	)

Toggles a GPIO group.

Parameters

port	The port number.
mask	The mask.

void gpio_toggle_pin

(

uint32_t

pin

)

Toggles a GPIO pin.

Parameters

pin	The pin number.

Note

The function gpio_configure_pin must be called before.