External Interrupt Controller

Functions for configuring and using the External Interrupt Controller. More...

Typedefs
typedef enum eic_interrupt_trigger_t	eic_interrupt_trigger_t
	An enum defining the types of interrupt trigger you wish to scan for.
typedef void(*	eic_cb_t) (uint8_t channel)

Enumerations
enum	eic_interrupt_trigger_t { INTERRUPT_TRIGGER_NONE = 0 , INTERRUPT_TRIGGER_RISING , INTERRUPT_TRIGGER_FALLING , INTERRUPT_TRIGGER_BOTH }
	An enum defining the types of interrupt trigger you wish to scan for.

Functions
void	eic_init (void)
	Initializes the external interrupt controller, but does not enable it.
void	eic_enable (void)
	Enables the external interrupt controller.
int8_t	eic_configure_pin (const uint8_t pin, eic_interrupt_trigger_t trigger)
	Configures an external interrupt on one of the external interrupt pins.
bool	eic_enable_interrupt (const uint8_t pin)
	Enables an interrupt on the given interrupt channel.
bool	eic_disable_interrupt (const uint8_t pin)
	Disables the interrupt on the given interrupt channel.
bool	eic_enable_event (const uint8_t pin)
	Enables an interrupt on the given interrupt channel.
bool	eic_disable_event (const uint8_t pin)
	Disables the interrupt on the given interrupt channel.
void	eic_configure_callback (eic_cb_t callback)
	Configures an external interrupt callback.
void	eic_disable (void)
	Disables the external interrupt controller.

Detailed Description

Functions for configuring and using the External Interrupt Controller.

Function Documentation

eic_configure_callback()

void eic_configure_callback

(

eic_cb_t

callback

)

Configures an external interrupt callback.

You only get the one callback, so if you need to handle multiple interrupts, you'll need to check the EIC->INTFLAG register in your callback to determine which interrupt fired.

Parameters

callback

The function that will be called when the interrupt fires.

Note

This function is called from the interrupt handler, so it should be as short as possible.

eic_configure_pin()

int8_t eic_configure_pin	(	const uint8_t	pin,
		eic_interrupt_trigger_t	trigger
	)

Configures an external interrupt on one of the external interrupt pins.

This function configures the interrupt channel with the specified trigger, but it does not set pin direction, mux or pull; you must set up the pin yourself. This function also does not enable an interrupt or event generation. You must call eic_enable_interrupt() or eic_enable_event() to either wake the processor or generate an event for a peripheral.

Parameters

pin	The external interrupt pin you wish to configure — use HAL_GPIO_xxx_PIN() macro.
trigger	The condition on which you wish to trigger: rising, falling or both.

Returns

the EIC channel number associated with the pin, or -1 if the pin is not an interrupt pin.

Note

Be sure to check your pin multiplexing table to ensure that you do not have multiple pins assigned to the same interrupt channel. Also note that the NMI pin is not currently supported.

FIXME: Should we have macros for this that accept a port / pin?

eic_disable_event()

bool eic_disable_event

(

const uint8_t

pin

)

Disables the interrupt on the given interrupt channel.

Parameters

pin	The external interrupt pin.

eic_disable_interrupt()

bool eic_disable_interrupt

(

const uint8_t

pin

)

Disables the interrupt on the given interrupt channel.

Parameters

pin	The external interrupt pin.

eic_enable_event()

bool eic_enable_event

(

const uint8_t

pin

)

Enables an interrupt on the given interrupt channel.

Parameters

pin	The external interrupt pin.

eic_enable_interrupt()

bool eic_enable_interrupt

(

const uint8_t

pin

)

Enables an interrupt on the given interrupt channel.

Parameters

pin	The external interrupt pin.