Pulse Width Modulation (PWM)

See Quickstart guide for SAM PWM module.

Driver for the PWM (Pulse Width Modulation). This driver provides access to the main features of the PWM controller.

Modules
	Related Project(s)
	In this section you can find all the projects related to the Pulse Width Modulation (PWM).
	Quick Start Guide(s)
	In this section you can find a list of all Quick Start guides related to the Pulse Width Modulation (PWM).

Macros
#define	PWM_CLOCK_DIV_MAX   256
#define	PWM_CLOCK_PRE_MAX   11
#define	PWM_WPCR_WPCMD_DISABLE_SW_PROT   (PWM_WPCR_WPCMD(0))
#define	PWM_WPCR_WPCMD_ENABLE_HW_PROT   (PWM_WPCR_WPCMD(2))
#define	PWM_WPCR_WPCMD_ENABLE_SW_PROT   (PWM_WPCR_WPCMD(1))
#define	PWM_WPCR_WPKEY_PASSWD   0x50574D00

Functions
void	pwm_channel_disable (Pwm *p_pwm, uint32_t ul_channel)
	Disable the PWM channel. More...
void	pwm_channel_disable_interrupt (Pwm *p_pwm, uint32_t ul_event, uint32_t ul_fault)
	Disable the interrupt of a channel counter event and fault protection. More...
void	pwm_channel_enable (Pwm *p_pwm, uint32_t ul_channel)
	Enable the PWM channel. More...
void	pwm_channel_enable_interrupt (Pwm *p_pwm, uint32_t ul_event, uint32_t ul_fault)
	Enable the interrupt of a channel counter event and fault protection. More...
uint32_t	pwm_channel_get_counter (Pwm *p_pwm, pwm_channel_t *p_channel)
	Return channel counter value. More...
uint32_t	pwm_channel_get_interrupt_mask (Pwm *p_pwm)
	Get channel counter event and fault protection trigger interrupt mask. More...
uint32_t	pwm_channel_get_interrupt_status (Pwm *p_pwm)
	Get channel counter event and fault protection trigger interrupt status. More...
uint32_t	pwm_channel_get_status (Pwm *p_pwm)
	Check which PWM channel is enabled. More...
uint32_t	pwm_channel_init (Pwm *p_pwm, pwm_channel_t *p_channel)
	Initialize one PWM channel. More...
uint32_t	pwm_channel_update_duty (Pwm *p_pwm, pwm_channel_t *p_channel, uint32_t ul_duty)
	Change the duty cycle of the PWM channel. More...
uint32_t	pwm_channel_update_period (Pwm *p_pwm, pwm_channel_t *p_channel, uint32_t ul_period)
	Change the period of the PWM channel. More...
static uint32_t	pwm_clocks_generate (uint32_t ul_frequency, uint32_t ul_mck)
	Find a prescaler/divisor couple to generate the desired ul_frequency from ul_mck. More...
uint32_t	pwm_init (Pwm *p_pwm, pwm_clock_t *clock_config)
	Initialize the PWM source clock (clock A and clock B). More...

#define PWM_CLOCK_DIV_MAX   256

Referenced by pwm_clocks_generate().

#define PWM_CLOCK_PRE_MAX   11

Referenced by pwm_clocks_generate().

#define PWM_WPCR_WPCMD_DISABLE_SW_PROT   (PWM_WPCR_WPCMD(0))

#define PWM_WPCR_WPCMD_ENABLE_HW_PROT   (PWM_WPCR_WPCMD(2))

#define PWM_WPCR_WPCMD_ENABLE_SW_PROT   (PWM_WPCR_WPCMD(1))

#define PWM_WPCR_WPKEY_PASSWD   0x50574D00

void pwm_channel_disable	(	Pwm *	p_pwm,
		uint32_t	ul_channel
	)

Disable the PWM channel.

Note

A disabled PWM channel can be re-initialized using pwm_channel_init().

Parameters

p_pwm	Pointer to a PWM instance.
ul_channel	PWM channel number to disable.

Referenced by main(), and run_pwm_test().

void pwm_channel_disable_interrupt	(	Pwm *	p_pwm,
		uint32_t	ul_event,
		uint32_t	ul_fault
	)

Disable the interrupt of a channel counter event and fault protection.

Parameters

p_pwm	Pointer to a PWM instance.
ul_event	Bitmask of channel number to disable counter event interrupt.
ul_fault	Bitmask of channel number to disable fault protection interrupt(ignored by SAM3N/SAM4N/SAM4C/SAM4CP/SAM4CM).

References UNUSED.

Referenced by main(), and run_pwm_test().

void pwm_channel_enable	(	Pwm *	p_pwm,
		uint32_t	ul_channel
	)

Enable the PWM channel.

Note

The PWM channel should be initialized by pwm_channel_init() before it is enabled.

Parameters

p_pwm	Pointer to a PWM instance.
ul_channel	PWM channel number to enable.

Referenced by main(), and run_pwm_test().

void pwm_channel_enable_interrupt	(	Pwm *	p_pwm,
		uint32_t	ul_event,
		uint32_t	ul_fault
	)

Enable the interrupt of a channel counter event and fault protection.

Parameters

p_pwm	Pointer to a PWM instance.
ul_event	Channel number to enable counter event interrupt.
ul_fault	Channel number to enable fault protection interrupt(ignored by SAM3N/SAM4N/SAM4C/SAM4CP/SAM4CM).

References UNUSED.

Referenced by main(), and run_pwm_test().

uint32_t pwm_channel_get_counter	(	Pwm *	p_pwm,
		pwm_channel_t *	p_channel
	)

Return channel counter value.

Parameters

p_pwm	Pointer to a PWM instance.
p_channel	Configurations of the specified PWM channel.

Returns

channel Counter value.

References pwm_channel_t::channel.

uint32_t pwm_channel_get_interrupt_mask

(

Pwm *

p_pwm

)

Get channel counter event and fault protection trigger interrupt mask.

Parameters

p_pwm

Pointer to a PWM instance.

Returns

Channel counter event and fault protection trigger interrupt mask.

uint32_t pwm_channel_get_interrupt_status

(

Pwm *

p_pwm

)

Get channel counter event and fault protection trigger interrupt status.

Parameters

p_pwm

Pointer to a PWM instance.

Returns

Channel counter event and fault protection trigger interrupt status.

Referenced by PWM_Handler().

uint32_t pwm_channel_get_status

(

Pwm *

p_pwm

)

Check which PWM channel is enabled.

Parameters

p_pwm	Pointer to a PWM instance.
p_channel	Configurations of the specified PWM channel.

Returns

Bitmask of enabled PWM channel(s).

uint32_t pwm_channel_init	(	Pwm *	p_pwm,
		pwm_channel_t *	p_channel
	)

Initialize one PWM channel.

Parameters

p_pwm	Pointer to a PWM instance.
p_channel	Configurations of the specified PWM channel.

Return values

0	if initialization succeeds, otherwise fails.

References pwm_channel_t::alignment, pwm_channel_t::channel, pwm_channel_t::polarity, PWM_HIGH, pwm_channel_t::ul_duty, pwm_channel_t::ul_period, and pwm_channel_t::ul_prescaler.

Referenced by main(), and run_pwm_test().

uint32_t pwm_channel_update_duty	(	Pwm *	p_pwm,
		pwm_channel_t *	p_channel,
		uint32_t	ul_duty
	)

Change the duty cycle of the PWM channel.

Parameters

p_pwm	Pointer to a PWM instance.
p_channel	Configurations of the specified PWM channel.
ul_duty	New duty cycle value.

Return values

0	if changing succeeds, otherwise fails.

Check parameter

References pwm_channel_t::channel, PWM_INVALID_ARGUMENT, pwm_channel_t::ul_duty, and pwm_channel_t::ul_period.

Referenced by PWM_Handler().

uint32_t pwm_channel_update_period	(	Pwm *	p_pwm,
		pwm_channel_t *	p_channel,
		uint32_t	ul_period
	)

Change the period of the PWM channel.

Parameters

p_pwm	Pointer to a PWM instance.
p_channel	Configurations of the specified PWM channel.
ul_period	New period value.

Return values

0	if changing succeeds, otherwise fails.

Check parameter

References pwm_channel_t::channel, PWM_INVALID_ARGUMENT, pwm_channel_t::ul_duty, and pwm_channel_t::ul_period.

static uint32_t pwm_clocks_generate ( uint32_t  ul_frequency, uint32_t  ul_mck  )

static

Find a prescaler/divisor couple to generate the desired ul_frequency from ul_mck.

Parameters

ul_frequency	Desired frequency in Hz.
ul_mck	Master clock frequency in Hz.

Return values

Return

the value to be set in the PWM Clock Register (PWM Mode Register for SAM3N/SAM4N/SAM4C/SAM4CP/SAM4CM) or PWM_INVALID_ARGUMENT if the configuration cannot be met.

References PWM_CLOCK_DIV_MAX, PWM_CLOCK_PRE_MAX, and PWM_INVALID_ARGUMENT.

Referenced by pwm_init().

uint32_t pwm_init	(	Pwm *	p_pwm,
		pwm_clock_t *	clock_config
	)

Initialize the PWM source clock (clock A and clock B).

Parameters

p_pwm	Pointer to a PWM instance.
clock_config	PWM clock configuration.

Return values

0	if initialization succeeds, otherwise fails.

References pwm_clocks_generate(), PWM_INVALID_ARGUMENT, pwm_clock_t::ul_clka, pwm_clock_t::ul_clkb, and pwm_clock_t::ul_mck.

Referenced by main(), and run_pwm_test().