PWM Driver APIs

PWM driver APIs. More...

Data Structures
struct	pwm_param

Macros
#define	PWM_DEPTH   1023

Functions
void	pwm_init (uint32 period, uint32 *duty, uint32 pwm_channel_num, uint32(*pin_info_list)[3])
	PWM function initialization, including GPIO, frequency and duty cycle. More...
void	pwm_set_duty (uint32 duty, uint8 channel)
	Set the duty cycle of a PWM channel. More...
uint32	pwm_get_duty (uint8 channel)
	Get the duty cycle of a PWM channel. More...
void	pwm_set_period (uint32 period)
	Set PWM period, unit : us. More...
uint32	pwm_get_period (void)
	Get PWM period, unit : us. More...
void	pwm_start (void)
	Starts PWM. More...

Detailed Description

PWM driver APIs.

Function Documentation

uint32 pwm_get_duty

(

uint8

channel

)

Get the duty cycle of a PWM channel.

Parameters

uint8

channel : PWM channel number

Returns

Duty cycle of PWM output.

uint32 pwm_get_period

(

void

)

Get PWM period, unit : us.

Parameters

null

Returns

PWM period, unit : us.

void pwm_init	(	uint32	period,
		uint32 *	duty,
		uint32	pwm_channel_num,
		uint32(*)	pin_info_list[3]
	)

PWM function initialization, including GPIO, frequency and duty cycle.

Attention

This API can be called only once.

Parameters

uint32	period : pwm frequency
uint32	*duty : duty cycle
uint32	pwm_channel_num : PWM channel number
uint32	(*pin_info_list)[3] : GPIO parameter of PWM channel, it is a pointer of n x 3 array which defines GPIO register, IO reuse of corresponding pin and GPIO number.

Returns

null

void pwm_set_duty	(	uint32	duty,
		uint8	channel
	)

Set the duty cycle of a PWM channel.

Set the time that high level signal will last, duty depends on period, the maximum value can be 1023.

Attention

After set configuration, pwm_start needs to be called to take effect.

Parameters

uint32	duty : duty cycle
uint8	channel : PWM channel number

Returns

null

void pwm_set_period

(

uint32

period

)

Set PWM period, unit : us.

For example, for 1KHz PWM, period is 1000 us.

Attention

After set configuration, pwm_start needs to be called to take effect.

Parameters

uint32

period : PWM period, unit : us.

Returns

null

void pwm_start

(

void

)

Starts PWM.

Attention

This function needs to be called after PWM configuration is changed.

Parameters

null

Returns

null