Pulse Width Modulation (PWM) peripheral driver. More...

Modules
	PWM peripheral driver configuration

Data Structures
struct	nrfx_pwm_t
	PWM driver instance data structure. More...

struct	nrfx_pwm_config_t
	PWM driver configuration structure. More...

Macros
#define	NRFX_PWM_INSTANCE(id)
	Macro for creating a PWM driver instance. More...

#define	NRFX_PWM_PIN_NOT_USED 0xFF
	This value can be provided instead of a pin number for any channel to specify that its output is not used and therefore does not need to be connected to a pin.

#define	NRFX_PWM_PIN_INVERTED 0x80
	This value can be added to a pin number to invert its polarity (set idle state = 1).

#define	NRFX_PWM_DEFAULT_CONFIG
	PWM driver default configuration. More...

Typedefs
typedef void(*	nrfx_pwm_handler_t )(nrfx_pwm_evt_type_t event_type)
	PWM driver event handler type.

Enumerations
enum	nrfx_pwm_flag_t { NRFX_PWM_FLAG_STOP = 0x01, NRFX_PWM_FLAG_LOOP = 0x02, NRFX_PWM_FLAG_SIGNAL_END_SEQ0 = 0x04, NRFX_PWM_FLAG_SIGNAL_END_SEQ1 = 0x08, NRFX_PWM_FLAG_NO_EVT_FINISHED = 0x10, NRFX_PWM_FLAG_START_VIA_TASK = 0x80 }
	PWM flags that provide additional playback options. More...

enum	nrfx_pwm_evt_type_t { NRFX_PWM_EVT_FINISHED, NRFX_PWM_EVT_END_SEQ0, NRFX_PWM_EVT_END_SEQ1, NRFX_PWM_EVT_STOPPED }
	PWM driver event type. More...

Functions
nrfx_err_t	nrfx_pwm_init (nrfx_pwm_t const const p_instance, nrfx_pwm_config_t const p_config, nrfx_pwm_handler_t handler)
	Function for initializing the PWM driver. More...

void	nrfx_pwm_uninit (nrfx_pwm_t const *const p_instance)
	Function for uninitializing the PWM driver. More...

uint32_t	nrfx_pwm_simple_playback (nrfx_pwm_t const const p_instance, nrf_pwm_sequence_t const p_sequence, uint16_t playback_count, uint32_t flags)
	Function for starting a single sequence playback. More...

uint32_t	nrfx_pwm_complex_playback (nrfx_pwm_t const const p_instance, nrf_pwm_sequence_t const p_sequence_0, nrf_pwm_sequence_t const *p_sequence_1, uint16_t playback_count, uint32_t flags)
	Function for starting a two-sequence playback. More...

__STATIC_INLINE void	nrfx_pwm_step (nrfx_pwm_t const *const p_instance)
	Function for advancing the active sequence. More...

bool	nrfx_pwm_stop (nrfx_pwm_t const *const p_instance, bool wait_until_stopped)
	Function for stopping the sequence playback. More...

bool	nrfx_pwm_is_stopped (nrfx_pwm_t const *const p_instance)
	Function for checking the status of the PWM peripheral. More...

__STATIC_INLINE void	nrfx_pwm_sequence_update (nrfx_pwm_t const const p_instance, uint8_t seq_id, nrf_pwm_sequence_t const p_sequence)
	Function for updating the sequence data during playback. More...

__STATIC_INLINE void	nrfx_pwm_sequence_values_update (nrfx_pwm_t const *const p_instance, uint8_t seq_id, nrf_pwm_values_t values)
	Function for updating the pointer to the duty cycle values in the specified sequence during playback. More...

__STATIC_INLINE void	nrfx_pwm_sequence_length_update (nrfx_pwm_t const *const p_instance, uint8_t seq_id, uint16_t length)
	Function for updating the number of duty cycle values in the specified sequence during playback. More...

__STATIC_INLINE void	nrfx_pwm_sequence_repeats_update (nrfx_pwm_t const *const p_instance, uint8_t seq_id, uint32_t repeats)
	Function for updating the number of repeats for duty cycle values in the specified sequence during playback. More...

__STATIC_INLINE void	nrfx_pwm_sequence_end_delay_update (nrfx_pwm_t const *const p_instance, uint8_t seq_id, uint32_t end_delay)
	Function for updating the additional delay after the specified sequence during playback. More...

__STATIC_INLINE uint32_t	nrfx_pwm_task_address_get (nrfx_pwm_t const *const p_instance, nrf_pwm_task_t task)
	Function for returning the address of a specified PWM task that can be used in PPI module. More...

__STATIC_INLINE uint32_t	nrfx_pwm_event_address_get (nrfx_pwm_t const *const p_instance, nrf_pwm_event_t event)
	Function for returning the address of a specified PWM event that can be used in PPI module. More...

Detailed Description

Pulse Width Modulation (PWM) peripheral driver.

Macro Definition Documentation

#define NRFX_PWM_DEFAULT_CONFIG

Value:

{ \
 .output_pins = { NRFX_PWM_DEFAULT_CONFIG_OUT0_PIN, \
 NRFX_PWM_DEFAULT_CONFIG_OUT1_PIN, \
 NRFX_PWM_DEFAULT_CONFIG_OUT2_PIN, \
 NRFX_PWM_DEFAULT_CONFIG_OUT3_PIN }, \
 .irq_priority = NRFX_PWM_DEFAULT_CONFIG_IRQ_PRIORITY, \
 .base_clock = (nrf_pwm_clk_t)NRFX_PWM_DEFAULT_CONFIG_BASE_CLOCK, \
 .count_mode = (nrf_pwm_mode_t)NRFX_PWM_DEFAULT_CONFIG_COUNT_MODE, \
 .top_value = NRFX_PWM_DEFAULT_CONFIG_TOP_VALUE, \
 .load_mode = (nrf_pwm_dec_load_t)NRFX_PWM_DEFAULT_CONFIG_LOAD_MODE, \
 .step_mode = (nrf_pwm_dec_step_t)NRFX_PWM_DEFAULT_CONFIG_STEP_MODE, \
}

PWM driver default configuration.

#define NRFX_PWM_INSTANCE ( id )

Value:

{ \
 .p_registers = NRFX_CONCAT_2(NRF_PWM, id), \
 .drv_inst_idx = NRFX_CONCAT_3(NRFX_PWM, id, _INST_IDX), \
}

Macro for creating a PWM driver instance.

Enumeration Type Documentation

enum nrfx_pwm_evt_type_t

PWM driver event type.

Enumerator
NRFX_PWM_EVT_FINISHED	Sequence playback finished.
NRFX_PWM_EVT_END_SEQ0	End of sequence 0 reached. Its data can be safely modified now.
NRFX_PWM_EVT_END_SEQ1	End of sequence 1 reached. Its data can be safely modified now.
NRFX_PWM_EVT_STOPPED	The PWM peripheral has been stopped.

enum nrfx_pwm_flag_t

PWM flags that provide additional playback options.

Enumerator
NRFX_PWM_FLAG_STOP	When the requested playback is finished, the peripheral will be stopped. Note The STOP task is triggered when the last value of the final sequence is loaded from RAM, and the peripheral stops at the end of the current PWM period. For sequences with configured repeating of duty cycle values, this might result in less than the requested number of repeats of the last value.
NRFX_PWM_FLAG_LOOP	When the requested playback is finished, it will be started from the beginning. This flag is ignored if used together with NRFX_PWM_FLAG_STOP. Note The playback restart is done via a shortcut configured in the PWM peripheral. This shortcut triggers the proper starting task when the final value of previous playback is read from RAM and applied to the pulse generator counter. When this mechanism is used together with the NRF_PWM_STEP_TRIGGERED mode, the playback restart will occur right after switching to the final value (this final value will be played only once).
NRFX_PWM_FLAG_SIGNAL_END_SEQ0	The event handler is to be called when the last value from sequence 0 is loaded.
NRFX_PWM_FLAG_SIGNAL_END_SEQ1	The event handler is to be called when the last value from sequence 1 is loaded.
NRFX_PWM_FLAG_NO_EVT_FINISHED	The playback finished event (enabled by default) is to be suppressed.
NRFX_PWM_FLAG_START_VIA_TASK	The playback must not be started directly by the called function. Instead, the function must only prepare it and return the address of the task to be triggered to start the playback.

Function Documentation

uint32_t nrfx_pwm_complex_playback	(	nrfx_pwm_t const *const	p_instance,
		nrf_pwm_sequence_t const *	p_sequence_0,
		nrf_pwm_sequence_t const *	p_sequence_1,
		uint16_t	playback_count,
		uint32_t	flags
	)

Function for starting a two-sequence playback.

Use the NRFX_PWM_FLAG_START_VIA_TASK flag if you want the playback to be only prepared by this function, and you want to start it later by triggering a task (using PPI for instance). The function will then return the address of the task to be triggered.

Note: The array containing the duty cycle values for the specified sequence must be in RAM and cannot be allocated on the stack. For detailed information, see nrf_pwm_sequence_t.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	p_sequence_0	First sequence to be played back.
[in]	p_sequence_1	Second sequence to be played back.
[in]	playback_count	Number of playbacks to be performed (must not be 0).
[in]	flags	Additional options. Pass any combination of playback flags, or 0 for default settings.

Returns: Address of the task to be triggered to start the playback if the NRFX_PWM_FLAG_START_VIA_TASK flag was used, 0 otherwise.

__STATIC_INLINE uint32_t nrfx_pwm_event_address_get	(	nrfx_pwm_t const *const	p_instance,
		nrf_pwm_event_t	event
	)

Function for returning the address of a specified PWM event that can be used in PPI module.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	event	Requested event.

Returns: Event address.

nrfx_err_t nrfx_pwm_init	(	nrfx_pwm_t const *const	p_instance,
		nrfx_pwm_config_t const *	p_config,
		nrfx_pwm_handler_t	handler
	)

Function for initializing the PWM driver.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	p_config	Pointer to the structure with the initial configuration.
[in]	handler	Event handler provided by the user. If NULL is passed instead, event notifications are not done and PWM interrupts are disabled.

Return values

NRFX_SUCCESS	Initialization was successful.
NRFX_ERROR_INVALID_STATE	The driver was already initialized.

bool nrfx_pwm_is_stopped ( nrfx_pwm_t const *const p_instance )

Function for checking the status of the PWM peripheral.

Parameters

[in] p_instance Pointer to the driver instance structure.

Return values

true	The PWM peripheral is stopped.
false	The PWM peripheral is not stopped.

__STATIC_INLINE void nrfx_pwm_sequence_end_delay_update	(	nrfx_pwm_t const *const	p_instance,
		uint8_t	seq_id,
		uint32_t	end_delay
	)

Function for updating the additional delay after the specified sequence during playback.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	seq_id	Identifier of the sequence (0 or 1).
[in]	end_delay	New end delay value (in PWM periods).

__STATIC_INLINE void nrfx_pwm_sequence_length_update	(	nrfx_pwm_t const *const	p_instance,
		uint8_t	seq_id,
		uint16_t	length
	)

Function for updating the number of duty cycle values in the specified sequence during playback.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	seq_id	Identifier of the sequence (0 or 1).
[in]	length	New number of the duty cycle values.

__STATIC_INLINE void nrfx_pwm_sequence_repeats_update	(	nrfx_pwm_t const *const	p_instance,
		uint8_t	seq_id,
		uint32_t	repeats
	)

Function for updating the number of repeats for duty cycle values in the specified sequence during playback.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	seq_id	Identifier of the sequence (0 or 1).
[in]	repeats	New number of repeats.

__STATIC_INLINE void nrfx_pwm_sequence_update	(	nrfx_pwm_t const *const	p_instance,
		uint8_t	seq_id,
		nrf_pwm_sequence_t const *	p_sequence
	)

Function for updating the sequence data during playback.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	seq_id	Identifier of the sequence (0 or 1).
[in]	p_sequence	Pointer to the new sequence definition.

__STATIC_INLINE void nrfx_pwm_sequence_values_update	(	nrfx_pwm_t const *const	p_instance,
		uint8_t	seq_id,
		nrf_pwm_values_t	values
	)

Function for updating the pointer to the duty cycle values in the specified sequence during playback.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	seq_id	Identifier of the sequence (0 or 1).
[in]	values	New pointer to the duty cycle values.

uint32_t nrfx_pwm_simple_playback	(	nrfx_pwm_t const *const	p_instance,
		nrf_pwm_sequence_t const *	p_sequence,
		uint16_t	playback_count,
		uint32_t	flags
	)

Function for starting a single sequence playback.

To take advantage of the looping mechanism in the PWM peripheral, both sequences must be used (single sequence can be played back only once by the peripheral). Therefore, the provided sequence is internally set and played back as both sequence 0 and sequence 1. Consequently, if the end of sequence notifications are required, events for both sequences must be used (that is, both the NRFX_PWM_FLAG_SIGNAL_END_SEQ0 flag and the NRFX_PWM_FLAG_SIGNAL_END_SEQ1 flag must be specified, and the NRFX_PWM_EVT_END_SEQ0 event and the NRFX_PWM_EVT_END_SEQ1 event must be handled in the same way).

Use the NRFX_PWM_FLAG_START_VIA_TASK flag if you want the playback to be only prepared by this function, and you want to start it later by triggering a task (for example, by using PPI). The function will then return the address of the task to be triggered.

Note: The array containing the duty cycle values for the specified sequence must be in RAM and cannot be allocated on the stack. For detailed information, see nrf_pwm_sequence_t.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	p_sequence	Sequence to be played back.
[in]	playback_count	Number of playbacks to be performed (must not be 0).
[in]	flags	Additional options. Pass any combination of playback flags, or 0 for default settings.

Returns: Address of the task to be triggered to start the playback if the NRFX_PWM_FLAG_START_VIA_TASK flag was used, 0 otherwise.

__STATIC_INLINE void nrfx_pwm_step ( nrfx_pwm_t const *const p_instance )

Function for advancing the active sequence.

This function only applies to NRF_PWM_STEP_TRIGGERED mode.

Parameters

[in] p_instance Pointer to the driver instance structure.

bool nrfx_pwm_stop	(	nrfx_pwm_t const *const	p_instance,
		bool	wait_until_stopped
	)

Function for stopping the sequence playback.

The playback is stopped at the end of the current PWM period. This means that if the active sequence is configured to repeat each duty cycle value for a certain number of PWM periods, the last played value might appear on the output less times than requested.

Note: This function can be instructed to wait until the playback is stopped (by setting wait_until_stopped to true). Depending on the length of the PMW period, this might take a significant amount of time. Alternatively, the nrfx_pwm_is_stopped function can be used to poll the status, or the NRFX_PWM_EVT_STOPPED event can be used to get the notification when the playback is stopped, provided the event handler is defined.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	wait_until_stopped	If true, the function will not return until the playback is stopped.

Return values

true	The PWM peripheral is stopped.
false	The PWM peripheral is not stopped.

__STATIC_INLINE uint32_t nrfx_pwm_task_address_get	(	nrfx_pwm_t const *const	p_instance,
		nrf_pwm_task_t	task
	)

Function for returning the address of a specified PWM task that can be used in PPI module.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	task	Requested task.

Returns: Task address.

void nrfx_pwm_uninit ( nrfx_pwm_t const *const p_instance )

Function for uninitializing the PWM driver.

If any sequence playback is in progress, it is stopped immediately.

Parameters

[in] p_instance Pointer to the driver instance structure.

Modules

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

Enumeration Type Documentation

Function Documentation