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/*
* Author: Brendan Le Foll <brendan.le.foll@intel.com>
* Copyright (c) 2014 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#pragma once
#include "pwm.h"
#include "types.hpp"
#include <stdexcept>
namespace mraa
{
/**
* @brief API to Pulse Width Modulation
*
* This file defines the PWM interface for libmraa
*
* @snippet Pwm3-cycle.cpp Interesting
*/
class Pwm
{
public:
/**
* instanciates a PWM object on a pin
*
* @param pin the pin number used on your board
* @param owner if you are the owner of the pin the destructor will
* @param chipid the pwmchip to use, use only in raw mode
* unexport the pin from sysfs, default behaviour is you are the owner
* if the pinmapper exported it
*/
Pwm(int pin, bool owner = true, int chipid = -1)
{
if (chipid == -1) {
m_pwm = mraa_pwm_init(pin);
} else {
m_pwm = mraa_pwm_init_raw(chipid, pin);
}
if (m_pwm == NULL) {
throw std::invalid_argument("Error initialising PWM on pin");
}
if (!owner) {
mraa_pwm_owner(m_pwm, 0);
}
}
/**
* Pwm destructor
*/
~Pwm()
{
mraa_pwm_close(m_pwm);
}
/**
* Set the output duty-cycle percentage, as a float
*
* @param percentage A floating-point value representing percentage of
* output. The value should lie between 0.0f (representing on 0%) and
* 1.0f Values above or below this range will be set at either 0.0f or
* 1.0f
* @return Result of operation
*/
Result
write(float percentage)
{
return (Result) mraa_pwm_write(m_pwm, percentage);
}
/**
* Read the ouput duty-cycle percentage, as a float
*
* @return A floating-point value representing percentage of
* output. The value should lie between 0.0f (representing on 0%) and
* 1.0f Values above or below this range will be set at either 0.0f or
* 1.0f
*/
float
read()
{
return mraa_pwm_read(m_pwm);
}
/**
* Set the PWM period as seconds represented in a float
*
* @param period Period represented as a float in seconds
* @return Result of operation
*/
Result
period(float period)
{
return (Result) mraa_pwm_period(m_pwm, period);
}
/**
* Set period, milliseconds
*
* @param ms milliseconds for period
* @return Result of operation
*/
Result
period_ms(int ms)
{
return (Result) mraa_pwm_period_ms(m_pwm, ms);
}
/**
* Set period, microseconds
*
* @param us microseconds as period
* @return Result of operation
*/
Result
period_us(int us)
{
return (Result) mraa_pwm_period_us(m_pwm, us);
}
/**
* Set pulsewidth, As represnted by seconds in a (float)
*
* @param seconds The duration of a pulse
* @return Result of operation
*/
Result
pulsewidth(float seconds)
{
return (Result) mraa_pwm_pulsewidth(m_pwm, seconds);
}
/**
* Set pulsewidth, milliseconds
*
* @param ms milliseconds for pulsewidth
* @return Result of operation
*/
Result
pulsewidth_ms(int ms)
{
return (Result) mraa_pwm_pulsewidth_ms(m_pwm, ms);
}
/**
* The pulsewidth, microseconds
*
* @param us microseconds for pulsewidth
* @return Result of operation
*/
Result
pulsewidth_us(int us)
{
return (Result) mraa_pwm_pulsewidth_us(m_pwm, us);
}
/**
* Set the enable status of the PWM pin. None zero will assume on with
* output being driven and 0 will disable the output
*
* @param enable enable status of pin
* @return Result of operation
*/
Result
enable(bool enable)
{
if (enable)
return (Result) mraa_pwm_enable(m_pwm, 1);
else
return (Result) mraa_pwm_enable(m_pwm, 0);
}
/**
* Set the period and duty of a PWM object.
*
* @param period represented in ms.
* @param duty represnted in ms as float.
* @return Result of operation
*/
Result
config_ms(int period, float duty)
{
return (Result) mraa_pwm_config_ms(m_pwm, period, duty);
}
/**
* Set the period and duty (percent) of a PWM object.
*
* @param period as represented in ms.
* @param duty percentage i.e. 50% = 0.5f
* @return Result of operation
*/
Result
config_percent(int period, float duty)
{
return (Result) mraa_pwm_config_percent(m_pwm, period, duty);
}
/**
* Get the maximum pwm period in us
*
* @return max pwm in us
*/
int
max_period()
{
return mraa_pwm_get_max_period();
}
/**
* Get the minimum pwm period in us
*
* @return min pwm in us
*/
int
min_period()
{
return mraa_pwm_get_min_period();
}
private:
mraa_pwm_context m_pwm;
};
}
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