A pulse-width modulation digital output. More...

#include <PwmOut.h>

Public Member Functions
	PwmOut (PinName pin)
	Create a PwmOut connected to the specified pin. More...

void	write (float value)
	Set the output duty-cycle, specified as a percentage (float) More...

float	read ()
	Return the current output duty-cycle setting, measured as a percentage (float) More...

void	period (float seconds)
	Set the PWM period, specified in seconds (float), keeping the duty cycle the same. More...

void	period_ms (int ms)
	Set the PWM period, specified in milliseconds (int), keeping the duty cycle the same. More...

void	period_us (int us)
	Set the PWM period, specified in microseconds (int), keeping the duty cycle the same. More...

void	pulsewidth (float seconds)
	Set the PWM pulsewidth, specified in seconds (float), keeping the period the same. More...

void	pulsewidth_ms (int ms)
	Set the PWM pulsewidth, specified in milliseconds (int), keeping the period the same. More...

void	pulsewidth_us (int us)
	Set the PWM pulsewidth, specified in microseconds (int), keeping the period the same. More...

PwmOut &	operator= (float value)
	A operator shorthand for write() More...

PwmOut &	operator= (PwmOut &rhs)
	A operator shorthand for write() More...

	operator float ()
	An operator shorthand for read() More...

Detailed Description

A pulse-width modulation digital output.

Note: Synchronization level: Interrupt safe

Example

// Gradually change the intensity of the LED.
#include "mbed.h"
PwmOut led(LED1);
int main() {
    while(1) {
        led = led + 0.01;
        wait(0.2);
        if(led == 1.0) {
            led = 0;
        }
    }
}

Definition at line 53 of file PwmOut.h.

Constructor & Destructor Documentation

PwmOut ( PinName pin )

Create a PwmOut connected to the specified pin.

Parameters

pin	PwmOut pin to connect to

Definition at line 61 of file PwmOut.h.

Member Function Documentation

operator float ( )

An operator shorthand for read()

See also: PwmOut::read()

Definition at line 196 of file PwmOut.h.

PwmOut& operator= ( float value )

A operator shorthand for write()

See also: PwmOut::write()

Definition at line 176 of file PwmOut.h.

PwmOut& operator= ( PwmOut & rhs )

A operator shorthand for write()

See also: PwmOut::write()

Definition at line 186 of file PwmOut.h.

void period ( float seconds )

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

Parameters

seconds Change the period of a PWM signal in seconds (float) without modifying the duty cycle

Note: The resolution is currently in microseconds; periods smaller than this will be set to zero.

Definition at line 116 of file PwmOut.h.

void period_ms ( int ms )

Set the PWM period, specified in milliseconds (int), keeping the duty cycle the same.

Parameters

ms	Change the period of a PWM signal in milliseconds without modifying the duty cycle

Definition at line 126 of file PwmOut.h.

void period_us ( int us )

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

Parameters

us	Change the period of a PWM signal in microseconds without modifying the duty cycle

Definition at line 136 of file PwmOut.h.

void pulsewidth ( float seconds )

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

Parameters

seconds Change the pulse width of a PWM signal specified in seconds (float)

Definition at line 146 of file PwmOut.h.

void pulsewidth_ms ( int ms )

Set the PWM pulsewidth, specified in milliseconds (int), keeping the period the same.

Parameters

ms	Change the pulse width of a PWM signal specified in milliseconds

Definition at line 156 of file PwmOut.h.

void pulsewidth_us ( int us )

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

Parameters

us	Change the pulse width of a PWM signal specified in microseconds

Definition at line 166 of file PwmOut.h.

float read ( void )

Return the current output duty-cycle setting, measured as a percentage (float)

Returns: A floating-point value representing the current duty-cycle being output on the pin, measured as a percentage. The returned value will lie between 0.0f (representing on 0%) and 1.0f (representing on 100%).

Note: This value may not match exactly the value set by a previous write().

Definition at line 101 of file PwmOut.h.

void write ( float value )

Set the output duty-cycle, specified as a percentage (float)

Parameters

value A floating-point value representing the output duty-cycle, specified as a percentage. The value should lie between 0.0f (representing on 0%) and 1.0f (representing on 100%). Values outside this range will be saturated to 0.0f or 1.0f.

Definition at line 83 of file PwmOut.h.

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

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