ESP 2014-15

/**

 * *****************************************************************************

 * @file    timers.c

 * @author  Jorge

 * @version 1.0

 * @date    Oct 2014

 * @brief   This file contains drivers for Timer2

 *******************************************************************************

 * @copy

 *

 * THIS FILE CONTAINS A BASIC FUNCTION TO HANDLE TIMER2 IN PIC32MX795F512H

 * TO BE USED FOR THE COURSE OF EMBEDDED SYSTEMS PROGRAMMING.

 *

 * UNIVERSIDADE DE AVEIRO

 */

#include <stdio.h>

#include <stdlib.h>

#include <stdint.h>

#include <xc.h>

#include "timer_config.h"

int timer_enable(int timer)

{

    if(timer < 2 || timer > 5)

        return -1;

    switch (timer){

        case 2:

            T2CONbits.ON = 1;

            break;

        case 3:

            T3CONbits.ON = 1;

            break;

        case 4:

            T4CONbits.ON = 1;

            break;

        case 5:

            T5CONbits.ON = 1;

            break;

    }

    return 0;

}

int timer_disable(int timer)

{

    if(timer < 2 || timer > 5)

        return -1;

    switch (timer){

        case 2:

            T2CONbits.ON = 0;

            break;

        case 3:

            T3CONbits.ON = 0;

            break;

        case 4:

            T4CONbits.ON = 0;

            break;

        case 5:

            T5CONbits.ON = 0;

            break;

    }

    return 0;

}

int set_timer_freq(int timer,unsigned int freq)

{

    const unsigned int prescaler_values[] = {1, 2, 4, 8, 16, 32, 64, 256};

    if(freq > PBCLK || freq < MIN_FREQ)                            // frequency of timer out of bounds

        return -1;

    if(timer < 2 || timer > 5)

        return -1;

    unsigned int pr = MAX_PR_VALUE + 1;

    unsigned int i = 0;

    while(pr > MAX_PR_VALUE)

    {

        pr = (PBCLK / (prescaler_values[i] * freq)) - 1;

        i++;

    }

    i-=1;

    switch (timer){

        case 2:

            T2CONbits.TCKPS = i;

            PR2 = pr;

            TMR2 = 0;

            break;

        case 3:

            T3CONbits.TCKPS = i;

            PR3 = pr;

            TMR3 = 0;

            break;

        case 4:

            T4CONbits.TCKPS = i;

            PR4 = pr;

            TMR4 = 0;

            break;

        case 5:

            T5CONbits.TCKPS = i;

            PR5 = pr;

            TMR5 = 0;

            break;

    }

    return 0;

}

int read_timer_IntFlag(int timer)

{

    if(timer < 2 || timer > 5)

        return -1;

    switch (timer){

        case 2:

             return IFS0bits.T2IF;

        case 3:

             return IFS0bits.T3IF;

        case 4:

             return IFS0bits.T4IF;

        case 5:

             return IFS0bits.T5IF;

    }

    return 0;

}

int reset_timer_IntFlag(int timer)

{

    if(timer < 2 || timer > 5)

        return -1;

    switch (timer){

        case 2:

            IFS0bits.T2IF = 0;

            break;

        case 3:

             IFS0bits.T3IF = 0;

             break;

        case 4:

             IFS0bits.T4IF = 0;

             break;

        case 5:

             IFS0bits.T5IF = 0;

             break;

    }

    return 0;

}

int set_timer_Int(int timer, int enable, int priority)

{

    if(priority < 0 || priority > 7 || enable < 0 || enable > 1 || timer < 1 || timer > 5)

        return -1;

    switch (timer){

        case 2:

            IFS0bits.T2IF = 0;

            IPC2bits.T2IP = priority;

            IEC0bits.T2IE = enable;

            break;

        case 3:

            IFS0bits.T3IF = 0;

            IPC3bits.T3IP = priority;

            IEC0bits.T3IE = enable;

            break;

        case 4:

            IFS0bits.T4IF = 0;

            IPC4bits.T4IP = priority;

            IEC0bits.T4IE = enable;

            break;

        case 5:

            IFS0bits.T5IF = 0;

            IPC5bits.T5IP = priority;

            IEC0bits.T5IE = enable;

            break;

    }

    return 0;

}

int set_ALL_Int(int enable){

    if(enable < 0 || enable > 1)

        return -1;

    INTEnableSystemMultiVectoredInt();

    if(enable){

        EnableInterrupts();

    }else

        DisableInterrupts();

    return 0;

}