Pwm.h

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/*
    Pwm.h - Macros and Functions for accessing the PMW capabilities of AVRs.
    For AVR ATMega328p (Arduino Uno) and ATMega2560 (Arduino Mega).
    This is part of the AVRTools library.
    Copyright (c) 2014 Igor Mikolic-Torreira.  All right reserved.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
 
 
 
#ifndef Pwm_h
#define Pwm_h
 
 
#include <stdint.h>
 
#include <util/atomic.h>
 
#include "GpioPinMacros.h"
 
 
 
#define _writeGpioPinPwm( ddr, port, pin, nbr, chl, ocr, com, tccr, value )                 \
                                        do                                                  \
                                        {                                                   \
                                            if ( value <= 0 )                               \
                                            {                                               \
                                                tccr &= ~(1<<com);                          \
                                                port &= ~(1<<nbr);                          \
                                            }                                               \
                                            else if ( value >= 255 )                        \
                                            {                                               \
                                                tccr &= ~(1<<com);                          \
                                                port |= (1<<nbr);                           \
                                            }                                               \
                                            else                                            \
                                            {                                               \
                                                tccr |= (1<<com);                           \
                                                ATOMIC_BLOCK( ATOMIC_RESTORESTATE )         \
                                                {                                           \
                                                    ocr = value;                            \
                                                }                                           \
                                            }                                               \
                                        }                                                   \
                                        while ( 0 )
 
 
 
#define writeGpioPinPwm( pinName, value )       _writeGpioPinPwm( pinName, value )
 
 
 
 
inline void writeGpioPinPwmV( const GpioPinVariable& pinVar, uint8_t value )
{
    if ( value == 0 )
    {
        *(pinVar.tccr()) &= ~( 1 << pinVar.com() );
        *(pinVar.port()) &= ~( 1 << pinVar.bitNbr() );
 
    }
    else if ( value == 255 )
    {
        *(pinVar.tccr()) &= ~( 1 << pinVar.com() );
        *(pinVar.port()) |= ( 1 << pinVar.bitNbr() );
    }
    else
    {
        *(pinVar.tccr()) |= ( 1 << pinVar.com() );
        // Provide atomicity for 16-bit timers (not needed for 8-bit timers, but be safe)
        ATOMIC_BLOCK( ATOMIC_RESTORESTATE )
        {
            *(pinVar.ocr()) = value;
        }
    }
}
 
 
 
void initPwmTimer0();
 
 
void initPwmTimer1();
 
 
void initPwmTimer2();
 
 
void clearTimer0();
 
 
 
 
void clearTimer1();
 
 
void clearTimer2();
 
 
#if defined(__AVR_ATmega2560__)
 
 
void initPwmTimer3();
 
 
void initPwmTimer4();
 
 
 
void initPwmTimer5();
 
 
 
 
void clearTimer3();
 
 
void clearTimer4();
 
 
void clearTimer5();
 
#endif
 
#endif