2015-06-23 12:42:35 -07:00

156 lines
4.4 KiB
C

/* -*- mode: jde; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
Part of the Wiring project - http://wiring.uniandes.edu.co
Copyright (c) 2004-05 Hernando Barragan
This library 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 2.1 of the License, or (at your option) any later version.
This library 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 library; if not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330,
Boston, MA 02111-1307 USA
Modified 24 November 2006 by David A. Mellis
Modified 28-08-2009 for attiny84 R.Wiersma
Modified 09-10-2009 for attiny45 A.Saporetti
Modified 20-11-2010 - B.Cook - Correct a minor bug in attachInterrupt
*/
#include <inttypes.h>
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include <stdio.h>
#include "wiring_private.h"
volatile static voidFuncPtr intFunc[NUMBER_EXTERNAL_INTERRUPTS];
#if defined( MCUCR ) && ! defined( EICRA )
#define EICRA MCUCR
#endif
#if defined( GIMSK ) && ! defined( EIMSK )
#define EIMSK GIMSK
#endif
void attachInterrupt(uint8_t interruptNum, void (*userFunc)(void), int mode)
{
if ( interruptNum < NUMBER_EXTERNAL_INTERRUPTS )
{
/*
If attachInterrupt is called in succession for the same
interruptNum but a different userFunc then the following line
is not safe. Changing intFunc is not atomic.
intFunc[interruptNum] = userFunc;
*/
{
// save interrupt flag
uint8_t SaveSREG = SREG;
// disable interrupts
cli();
// access the shared data
intFunc[interruptNum] = userFunc;
// restore the interrupt flag
SREG = SaveSREG;
}
// Configure the interrupt mode (trigger on low input, any change, rising
// edge, or falling edge). The mode constants were chosen to correspond
// to the configuration bits in the hardware register, so we simply shift
// the mode into place.
// Enable the interrupt.
switch ( interruptNum )
{
#if NUMBER_EXTERNAL_INTERRUPTS >= 1
case EXTERNAL_INTERRUPT_0:
EICRA = (EICRA & ~((1 << ISC00) | (1 << ISC01))) | (mode << ISC00);
EIMSK |= (1 << INT0);
break;
#endif
#if NUMBER_EXTERNAL_INTERRUPTS >= 2 && !defined(ISC11)
//For ATtiny861, but interrupts share the same vector.
case EXTERNAL_INTERRUPT_1:
EICRA = (EICRA & ~((1 << ISC00) | (1 << ISC01))) | (mode << ISC00);
EIMSK |= (1 << INT1);
break;
#endif
#if NUMBER_EXTERNAL_INTERRUPTS >= 2 && defined(ISC11)
case EXTERNAL_INTERRUPT_1:
EICRA = (EICRA & ~((1 << ISC10) | (1 << ISC11))) | (mode << ISC10);
EIMSK |= (1 << INT1);
break;
#endif
#if NUMBER_EXTERNAL_INTERRUPTS > 2
#error Add handlers for the additional interrupts.
#endif
}
}
}
void detachInterrupt(uint8_t interruptNum)
{
if ( interruptNum < NUMBER_EXTERNAL_INTERRUPTS )
{
// Disable the interrupt. (We can't assume that interruptNum is equal
// to the number of the EIMSK bit to clear, as this isn't true on the
// ATmega8. There, INT0 is 6 and INT1 is 7.)
switch (interruptNum)
{
#if NUMBER_EXTERNAL_INTERRUPTS >= 1
case EXTERNAL_INTERRUPT_0:
EIMSK &= ~(1 << INT0);
break;;
#endif
#if NUMBER_EXTERNAL_INTERRUPTS >= 2
case EXTERNAL_INTERRUPT_1:
EIMSK &= ~(1 << INT1);
break;;
#endif
#if NUMBER_EXTERNAL_INTERRUPTS > 2
#error Add handlers for the additional interrupts.
#endif
}
intFunc[interruptNum] = 0;
}
}
#if NUMBER_EXTERNAL_INTERRUPTS >= 1
ISR(EXTERNAL_INTERRUPT_0_vect)
{
if(intFunc[EXTERNAL_INTERRUPT_0])
intFunc[EXTERNAL_INTERRUPT_0]();
}
#endif
#if NUMBER_EXTERNAL_INTERRUPTS >= 2
ISR(EXTERNAL_INTERRUPT_1_vect)
{
if(intFunc[EXTERNAL_INTERRUPT_1])
intFunc[EXTERNAL_INTERRUPT_1]();
}
#endif
#if NUMBER_EXTERNAL_INTERRUPTS > 2
#error Add handlers for the additional interrupts.
#endif