RtcHal.cpp

/*
 * MIT License
 *
 * Copyright (c) 2020 maciejkwasek
 *
 * 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.
 */

#include <stdbool.h>

#include <Arduino.h>

static volatile bool oneSecEvent;

/*
 *
 */
static void setupTimer1()
{
    // Clear registers
    TCCR1A = 0;
    TCCR1B = 0;
    TCNT1 = 0;

    // 1 Hz (16000000/((15624+1)*1024))
    OCR1A = 15624;
    // CTC
    TCCR1B |= (1 << WGM12);
    // Prescaler 1024
    TCCR1B |= (1 << CS12) | (1 << CS10);
    // Output Compare Match A Interrupt Enable
    TIMSK1 |= (1 << OCIE1A);
}

/*
 *
 */
ISR(TIMER1_COMPA_vect)
{
    oneSecEvent = true;
}

/*
 *
 */
void RtcHal_Init(void)
{
    setupTimer1();
    oneSecEvent = false;
}

/*
 *
 */
bool RtcHal_IsOneSecondEvent(void)
{
    bool result = false;

    if(oneSecEvent)
    {
        oneSecEvent = false;
        result = true;
    }

    return result;
}