Pwmout hal functions

Modules
	GPIO IRQ HAL tests
	The Pwmout HAL tests ensure driver conformance to defined behaviour.

Functions
void	pwmout_init_direct (pwmout_t *obj, const PinMap *pinmap)
	Initialize the pwm out peripheral and configure the pin. More...
void	pwmout_init (pwmout_t *obj, PinName pin)
	Initialize the pwm out peripheral and configure the pin. More...
void	pwmout_free (pwmout_t *obj)
	Deinitialize the pwmout object. More...
void	pwmout_write (pwmout_t *obj, float percent)
	Set the output duty-cycle in range <0.0f, 1.0f> More...
float	pwmout_read (pwmout_t *obj)
	Read the current float-point output duty-cycle. More...
void	pwmout_period (pwmout_t *obj, float seconds)
	Set the PWM period specified in seconds, keeping the duty cycle the same. More...
void	pwmout_period_ms (pwmout_t *obj, int ms)
	Set the PWM period specified in miliseconds, keeping the duty cycle the same. More...
void	pwmout_period_us (pwmout_t *obj, int us)
	Set the PWM period specified in microseconds, keeping the duty cycle the same. More...
int	pwmout_read_period_us (pwmout_t *obj)
	Read the PWM period specified in microseconds. More...
void	pwmout_pulsewidth (pwmout_t *obj, float seconds)
	Set the PWM pulsewidth specified in seconds, keeping the period the same. More...
void	pwmout_pulsewidth_ms (pwmout_t *obj, int ms)
	Set the PWM pulsewidth specified in miliseconds, keeping the period the same. More...
void	pwmout_pulsewidth_us (pwmout_t *obj, int us)
	Set the PWM pulsewidth specified in microseconds, keeping the period the same. More...
int	pwmout_read_pulsewidth_us (pwmout_t *obj)
	Read the PWM pulsewidth specified in microseconds. More...
const PinMap *	pwmout_pinmap (void)
	Get the pins that support PWM. More...

Detailed Description

Defined behavior

• pwmout_init initializes the pwmout_t control structure
• pwmout_free deinitializes the pwmout object
• pwmout_write sets the output duty-cycle in range <0.0f, 1.0f>
• pwmout_read returns the current float-point output duty-cycle in range <0.0f, 1.0f>
• pwmout_period sets the PWM period specified in seconds, keeping the duty cycle the same
• pwmout_period_ms sets the PWM period specified in miliseconds, keeping the duty cycle the same
• pwmout_period_us sets the PWM period specified in microseconds, keeping the duty cycle the same
• pwmout_read_period_us reads the PWM period specified in microseconds
• pwmout_pulsewidth sets the PWM pulsewidth specified in seconds, keeping the period the same
• pwmout_pulsewidth_ms sets the PWM pulsewidth specified in miliseconds, keeping the period the same
• pwmout_pulsewidth_us sets the PWM pulsewidth specified in microseconds, keeping the period the same
• pwmout_read_pulsewidth_us read the PWM pulsewidth specified in microseconds
• The accuracy of the PWM is +/- 10%
• The PWM operations pwmout_write, pwmout_read, pwmout_read, pwmout_period_ms, pwmout_period_us pwmout_pulsewidth, pwmout_pulsewidth_ms, pwmout_pulsewidth_us take less than 20us to complete

Undefined behavior

• Calling other function before pwmout_init
• Calling pwmout_init with NC as pwmout pin

Function Documentation

pwmout_init_direct()

void pwmout_init_direct	(	pwmout_t *	obj,
		const PinMap *	pinmap
	)

Initialize the pwm out peripheral and configure the pin.

Parameters

obj	The pwmout object to initialize
pinmap	pointer to structure which holds static pinmap

pwmout_init()

void pwmout_init	(	pwmout_t *	obj,
		PinName	pin
	)

Initialize the pwm out peripheral and configure the pin.

Parameters

obj	The pwmout object to initialize
pin	The pwmout pin to initialize

pwmout_free()

void pwmout_free

(

pwmout_t *

obj

)

Deinitialize the pwmout object.

Parameters

obj	The pwmout object

pwmout_write()

void pwmout_write	(	pwmout_t *	obj,
		float	percent
	)

Set the output duty-cycle in range <0.0f, 1.0f>

Value 0.0f represents 0 percentage, 1.0f represents 100 percent.

Parameters

obj	The pwmout object
percent	The floating-point percentage number

pwmout_read()

float pwmout_read

(

pwmout_t *

obj

)

Read the current float-point output duty-cycle.

Parameters

obj	The pwmout object

Returns

A floating-point output duty-cycle

pwmout_period()

void pwmout_period	(	pwmout_t *	obj,
		float	seconds
	)

Set the PWM period specified in seconds, keeping the duty cycle the same.

Periods smaller than microseconds (the lowest resolution) are set to zero.

Parameters

obj	The pwmout object
seconds	The floating-point seconds period

pwmout_period_ms()

void pwmout_period_ms	(	pwmout_t *	obj,
		int	ms
	)

Set the PWM period specified in miliseconds, keeping the duty cycle the same.

Parameters

obj	The pwmout object
ms	The milisecond period

pwmout_period_us()

void pwmout_period_us	(	pwmout_t *	obj,
		int	us
	)

Set the PWM period specified in microseconds, keeping the duty cycle the same.

Parameters

obj	The pwmout object
us	The microsecond period

pwmout_read_period_us()

int pwmout_read_period_us

(

pwmout_t *

obj

)

Read the PWM period specified in microseconds.

Parameters

obj	The pwmout object

Returns

A int output period

pwmout_pulsewidth()

void pwmout_pulsewidth	(	pwmout_t *	obj,
		float	seconds
	)

Set the PWM pulsewidth specified in seconds, keeping the period the same.

Parameters

obj	The pwmout object
seconds	The floating-point pulsewidth in seconds

pwmout_pulsewidth_ms()

void pwmout_pulsewidth_ms	(	pwmout_t *	obj,
		int	ms
	)

Set the PWM pulsewidth specified in miliseconds, keeping the period the same.

Parameters

obj	The pwmout object
ms	The floating-point pulsewidth in miliseconds

pwmout_pulsewidth_us()

void pwmout_pulsewidth_us	(	pwmout_t *	obj,
		int	us
	)

Set the PWM pulsewidth specified in microseconds, keeping the period the same.

Parameters

obj	The pwmout object
us	The floating-point pulsewidth in microseconds

pwmout_read_pulsewidth_us()

int pwmout_read_pulsewidth_us

(

pwmout_t *

obj

)

Read the PWM pulsewidth specified in microseconds.

Parameters

obj	The pwmout object

Returns

A int output pulsewidth

pwmout_pinmap()

const PinMap * pwmout_pinmap

(

void

)

Get the pins that support PWM.

Return a PinMap array of pins that support PWM. The array is terminated with {NC, NC, 0}.

Returns

PinMap array