1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/timer.c	Tue Oct 17 15:25:33 2017 +0300
     1.3 @@ -0,0 +1,35 @@
     1.4 +#include <avr/io.h>
     1.5 +#include <avr/interrupt.h>
     1.6 +#include <avr/power.h>
     1.7 +#include "timer.h"
     1.8 +
     1.9 +#define PRESCL_256	4
    1.10 +/* 256 ticks per interrupt, 256 clock divisor */
    1.11 +#define TICKS_PER_SEC	(F_CPU / 256 / 256)
    1.12 +
    1.13 +static volatile unsigned long ticks;
    1.14 +
    1.15 +void init_timer(void)
    1.16 +{
    1.17 +	power_timer0_enable();
    1.18 +
    1.19 +	TCCR0A = 0;
    1.20 +	TCCR0B = PRESCL_256;
    1.21 +
    1.22 +	TIMSK0 |= (1 << TOIE0);	/* enable ovf intr. */
    1.23 +}
    1.24 +
    1.25 +void reset_timer(void)
    1.26 +{
    1.27 +	ticks = 0;
    1.28 +}
    1.29 +
    1.30 +unsigned long get_msec(void)
    1.31 +{
    1.32 +	return 1000 * ticks / TICKS_PER_SEC;
    1.33 +}
    1.34 +
    1.35 +ISR(TIMER0_OVF_vect)
    1.36 +{
    1.37 +	++ticks;
    1.38 +}