A:/eclipse/mhvlib/MHV_PinChangeManager.cpp

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/*
 * Copyright (c) 2011, Make, Hack, Void Inc
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of the Make, Hack, Void nor the
 *    names of its contributors may be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL MAKE, HACK, VOID BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#include <MHV_PinChangeManager.h>

MHV_PinChangeManager::MHV_PinChangeManager() {
        for (uint8_t i = 0; i < MHV_PC_INT_COUNT; i++) {
                _pins[i].port = NULL;
        }
}

void MHV_PinChangeManager::pinChange0() {
        pinChange(0);
}

#if MHV_PC_INT_COUNT > 7

void MHV_PinChangeManager::pinChange1() {
        pinChange(8);
}
#endif

#if MHV_PC_INT_COUNT > 15

void MHV_PinChangeManager::pinChange2() {
        pinChange(16);
}
#endif

void MHV_PinChangeManager::pinChange(uint8_t offset) {
        MHV_EVENT_PIN *pin = _pins + offset;
        MHV_EVENT_PIN *maxPin = pin + 8;

        for (; pin < maxPin; ++pin) {
                if (NULL == pin->port) {
                        continue;
                }

                bool cur = *(pin->port) & pin->mask;
                if (cur != pin->previous) {
                        // Pin has changed
                        pin->previous = cur;
                        pin->changed = 1;
                        pin->listener->pinChanged(pin - _pins, cur);
                }
        }
}

void MHV_PinChangeManager::registerListener(MHV_DECLARE_PIN(pin), MHV_PinEventListener *listener) {

        mhv_setInput(MHV_PIN_PARMS(pin));

        _pins[pinPinchangeInterrupt].port = pinIn;
        _pins[pinPinchangeInterrupt].mask = _BV(pinPin);
        _pins[pinPinchangeInterrupt].listener = listener;
        _pins[pinPinchangeInterrupt].previous = mhv_pinRead(MHV_PIN_PARMS(pin));
        _pins[pinPinchangeInterrupt].changed = false;

        // Enable the interrupt
        uint8_t bit = pinPinchangeInterrupt;
#if MHV_PC_INT_COUNT > 15
        if (pinPinchangeInterrupt > 15) {
                bit -= 16;
                PCMSK2 |= _BV(bit);
                PCICR |= _BV(PCIE2);
        } else
#endif
#if MHV_PC_INT_COUNT > 7
        if (pinPinchangeInterrupt > 7) {
                bit -= 8;
                PCMSK1 |= _BV(bit);
                PCICR |= _BV(PCIE1);
        } else
#endif
#ifdef PCMSK0
        {
                PCMSK0 |= _BV(bit);
                PCICR |= _BV(PCIE0);
        }
#else
        {
                PCMSK |= _BV(bit);
                GIMSK |= _BV(PCIE);
        }
#endif
}

void MHV_PinChangeManager::deregisterListener(MHV_DECLARE_PIN(pin)) {

        _pins[pinPinchangeInterrupt].listener = NULL;
        _pins[pinPinchangeInterrupt].changed = false;

// Disable the interrupt
        uint8_t bit = pinPinchangeInterrupt;
#if MHV_PC_INT_COUNT > 15
        if (pinPinchangeInterrupt > 15) {
                bit -= 16;
                PCMSK2 &= ~_BV(bit);
        } else
#endif
#if MHV_PC_INT_COUNT > 7
        if (pinPinchangeInterrupt > 7) {
                bit -= 8;
                PCMSK1 &= ~_BV(bit);
        } else
#endif
#ifdef PCMSK0
        {
                PCMSK0 &= ~_BV(bit);
        }
#else
        {
                PCMSK &= ~_BV(bit);
        }
#endif
}

void MHV_PinChangeManager::handleEvents() {
        uint8_t i;

        for (i = 0; i < MHV_PC_INT_COUNT; i++) {
                if (_pins[i].changed) {
                        _pins[i].changed = 0;
                        _pins[i].listener->pinChanged(i, _pins[i].previous);
                }
        }
}