InterruptUtils.h

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/*
    InterruptUtils.h - Utilities for managing interrupts for
    AVR ATMega328p (Arduino Uno) and ATMega2560 (Arduino Mega).
    This is part of the AVRTools library.
    Copyright (c) 2015 Igor Mikolic-Torreira.  All right reserved.
    Functions printNumber() and printFloat() adapted from Arduino code that
    is Copyright (c) 2008 David A. Mellis and licensed under LGPL.

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser 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 Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/


#ifndef InterruptUtils_h
#define InterruptUtils_h

#include <stdint.h>
#include <stddef.h>

#include <avr/io.h>
#include <util/atomic.h>





namespace Interrupts
{

    class AllOff
    {
    public:

        AllOff()
        {
            mSreg = SREG;
            cli();
        }


        ~AllOff()
        {
            // Turn on global interrupt, only if it was already on.  Leave other bits alone.
            if ( mSreg & static_cast<uint8_t>(1 << SREG_I) )
            {
                sei();
            }
        }


    private:

        uint8_t mSreg;
    };







#if defined(__AVR_ATmega328P__)
#define kExternalInterruptMask         0x03
#elif defined(__AVR_ATmega2560__)
#define kExternalInterruptMask         0xFF
#else
#error "Undefined AVR processor type"
#endif


    enum ExternalInterrupts
    {
        kExternalInterrupt0     = ( 1 << INT0 ),    
        kExternalInterrupt1     = ( 1 << INT1 ),    

#if defined(__AVR_ATmega2560__)
        kExternalInterrupt2     = ( 1 << INT2 ),    
        kExternalInterrupt3     = ( 1 << INT3 ),    
        kExternalInterrupt4     = ( 1 << INT4 ),    
        kExternalInterrupt5     = ( 1 << INT5 ),    
        kExternalInterrupt6     = ( 1 << INT6 ),    
        kExternalInterrupt7     = ( 1 << INT7 ),    
#endif

        kExternalInterruptAll   = kExternalInterruptMask    
    };



    class ExternalOff
    {
    public:

        ExternalOff( uint8_t whichOnesToTurnOff = kExternalInterruptMask )
        : mExternalInterruptsToSuppress( whichOnesToTurnOff & kExternalInterruptMask )
        {
            // Disable the selected interrupts
            EIMSK &= ~(mExternalInterruptsToSuppress);
        }


        ~ExternalOff()
        {
            // Enable the selected interrupts
            EIMSK |= mExternalInterruptsToSuppress;
        }


    private:

        uint8_t mExternalInterruptsToSuppress;
    };







#if defined(__AVR_ATmega328P__)
#define kPinChangeInterruptMask         0x07
#elif defined(__AVR_ATmega2560__)
#define kPinChangeInterruptMask         0x07
#else
#error "Undefined AVR processor type"
#endif


    enum PinChangeInterrupts
    {
        kPinChangeInterrupt0     = ( 1 << PCINT0 ),           
        kPinChangeInterrupt1     = ( 1 << PCINT1 ),           
        kPinChangeInterrupt2     = ( 1 << PCINT2 ),           
        kPinChangeInterruptAll   = kPinChangeInterruptMask  
    };



    class PinChangeOff
    {
    public:

        PinChangeOff( uint8_t whichOnesToTurnOff = kPinChangeInterruptMask )
        : mPinChangeInterruptsToSuppress( whichOnesToTurnOff & kPinChangeInterruptMask )
        {
            // Disable the selected interrupts
            PCICR &= ~(mPinChangeInterruptsToSuppress);
        }


        ~PinChangeOff()
        {
            // Enable the selected interrupts
            PCICR |= mPinChangeInterruptsToSuppress;
        }


    private:

        uint8_t mPinChangeInterruptsToSuppress;
    };



};  // End namespace


#endif