Low-power PWM

nRF5 SDK v12.1.0
Modules | Data Structures | Macros | Typedefs | Enumerations | Functions

Module for generating a low-power pulse-width modulated output signal. More...

Modules

low_power_pwm module configuration

Data Structures

struct low_power_pwm_config_t
Structure holding the initialization parameters. More...

Macros

#define LOW_POWER_PWM_DEFAULT_CONFIG (mask)
Low-power PWM default configuration. More...

Typedefs

typedef void(* low_power_pwm_timeout_user )(void *p_context, low_power_pwm_evt_type_t evt_type)
Application time-out handler type.
typedef struct low_power_pwm_s low_power_pwm_t
Internal structure holding parameters of a low-power PWM instance.

Enumerations

enum low_power_pwm_evt_type_t {
LOW_POWER_PWM_EVENT_PERIOD = 0,
LOW_POWER_PWM_EVENT_DUTY_CYCLE
}
Event types.

Functions

ret_code_t low_power_pwm_init ( low_power_pwm_t *p_pwm_instance, low_power_pwm_config_t const *p_pwm_config, app_timer_timeout_handler_t handler)
Function for initializing a low-power PWM instance. More...
ret_code_t low_power_pwm_start ( low_power_pwm_t *p_pwm_instance, uint32_t leds_pin_bit_mask)
Function for starting a low-power PWM instance. More...
ret_code_t low_power_pwm_stop ( low_power_pwm_t *p_pwm_instance)
Function for stopping a low-power PWM instance. More...
ret_code_t low_power_pwm_duty_set ( low_power_pwm_t *p_pwm_instance, uint8_t duty_cycle)
Function for setting a new high pulse width for a given instance. More...

Default settings

Default parameters for the low_power_pwm_config_t structure.

#define LOW_POWER_PWM_CONFIG_ACTIVE_HIGH false
#define LOW_POWER_PWM_CONFIG_PERIOD UINT8_MAX
#define LOW_POWER_PWM_CONFIG_BIT_MASK (mask)   (mask)

Detailed Description

Module for generating a low-power pulse-width modulated output signal.

This module provides a low-power PWM implementation using app_timers and GPIO.

Each low-power PWM instance utilizes one app_timer. This means it runs on RTC and does not require HFCLK to be running. There can be any number of output channels per instance.

Macro Definition Documentation

#define LOW_POWER_PWM_DEFAULT_CONFIG ( mask )
Value:
{ \
.active_high = LOW_POWER_PWM_CONFIG_ACTIVE_HIGH , \
.period = LOW_POWER_PWM_CONFIG_PERIOD , \
.bit_mask = LOW_POWER_PWM_CONFIG_BIT_MASK(mask) \
}

Low-power PWM default configuration.

Function Documentation

ret_code_t low_power_pwm_duty_set ( low_power_pwm_t * p_pwm_instance ,
uint8_t duty_cycle
)

Function for setting a new high pulse width for a given instance.

This function can be called from the timer handler.

Parameters
[in] p_pwm_instance Pointer to the instance to be changed.
[in] duty_cycle New high pulse width. 0 means that the LED is always off. 255 means that it is always on.
Return values
NRF_SUCCESS If the function completed successfully.
NRF_ERROR_INVALID_PARAM If the function returned an error because of invalid parameters.
ret_code_t low_power_pwm_init ( low_power_pwm_t * p_pwm_instance ,
low_power_pwm_config_t const * p_pwm_config ,
app_timer_timeout_handler_t handler
)

Function for initializing a low-power PWM instance.

Parameters
[in] p_pwm_instance Pointer to the instance to be started.
[in] p_pwm_config Pointer to the configuration structure.
[in] handler User function to be called in case of time-out.
Returns
Values returned by app_timer_create .
ret_code_t low_power_pwm_start ( low_power_pwm_t * p_pwm_instance ,
uint32_t leds_pin_bit_mask
)

Function for starting a low-power PWM instance.

Parameters
[in] p_pwm_instance Pointer to the instance to be started.
[in] leds_pin_bit_mask Bit mask of pins to be started.
Returns
Values returned by app_timer_start .
ret_code_t low_power_pwm_stop ( low_power_pwm_t * p_pwm_instance )

Function for stopping a low-power PWM instance.

Parameters
[in] p_pwm_instance Pointer to the instance to be stopped.
Returns
Values returned by app_timer_stop .