timer_hal.c

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#include "user_config.h"

#include "lib/time.h"
#include "lib/timer.h"

// =============================================
#ifdef ESP8266
static ETSTimer task_1ms;

MEMSPACE
void disable_system_task()
{
    os_timer_disarm(&task_1ms);
}

MEMSPACE
void enable_system_task()
{
    os_timer_arm(&task_1ms, 1, 1);
}

MEMSPACE void install_timers_isr()
{
    os_timer_disarm(&task_1ms);
    os_timer_setfn(&task_1ms, ( os_timer_func_t *) execute_timers, NULL );
}
#endif  // ifdef ESP8266
// =============================================

// =============================================
#ifdef AVR
/*< We can read a high resolution hardware timer */
#define HAVE_HIRES_TIMER

#define TIMER1_PRESCALE     1L

#define TIMER1_COUNTS_PER_TIC (F_CPU/TIMER1_PRESCALE/SYSTEM_TASK_HZ)

#define TIMER1_COUNTER_RES (SYSTEM_TASK_TIC_NS/TIMER1_COUNTS_PER_TIC)

#if TIMER1_COUNTS_PER_TIC >= 65535L
#error TIMER1_COUNTS_PER_TIC too big -- increase TIMER1 Prescale
#endif

#define TIMER1_PRE_1 (1 << CS10)                        /*< 1 Prescale */
#define TIMER1_PRE_8 (1 << CS11)                        /*< 8 Prescale */
#define TIMER1_PRE_64 ((1 << CS11) | ( 1 << CS10))      /*< 64 Prescale */
#define TIMER1_PRE_256 (1 << CS12)                      /*< 256 Prescale */
#define TIMER1_PRE_1024 ((1 << CS12) | ( 1 << CS10))    /*< 1024 Prescape */

MEMSPACE
void disable_system_task()
{
    cli();
}

MEMSPACE
void enable_system_task()
{
    sei();
}

MEMSPACE void install_timers_isr()
{
    cli();
    TCCR1B=(1<<WGM12) | TIMER1_PRE_1;   // No Prescale
    TCCR1A=0;
    OCR1A=(TIMER1_COUNTS_PER_TIC-1);    // 0 .. count
    TIMSK1 |= (1<<OCIE1A);              //Enable the Output Compare A interrupt
    sei();
}

ISR(TIMER1_COMPA_vect)
{
    execute_timers();
}

#ifdef HAVE_HIRES_TIMER
MEMSPACE
int clock_gettime(clockid_t clk_id, struct timespec *ts)
{
    uint16_t count1,count2;                       // must be same size as timer register
    uint32_t offset = 0;
    uint8_t pendingf = 0;
    int errorf = 0;

    // disable interrupts
    cli();

    count1 = TCNT1;

    ts->tv_sec = __clock.tv_sec;
    ts->tv_nsec = __clock.tv_nsec;

    count2 = TCNT1;

    if( TIFR1 & (1<<OCF1A) )
        pendingf = 1;

    if (count2 < count1)
    {
        if( !pendingf )
            errorf = -1;    // counter overflow and NO pending is an error!
        offset = TIMER1_COUNTS_PER_TIC;           // overflow
    }
    else
    {
        if( pendingf )
            offset = TIMER1_COUNTS_PER_TIC;       // overflow
    }
    offset += count2;

    // enable interrupts
    sei();

    offset *= TIMER1_COUNTER_RES;

    ts->tv_nsec += offset;

    if (ts->tv_nsec >= 1000000000L)
    {
        ts->tv_nsec -= 1000000000L;
        ts->tv_sec++;
    }
    return(errorf);
}
#endif  // ifdef HAVE_HIRES_TIMER

#endif  // ifdef AVR
// =============================================