cube-kl/firmware/timer.c

#include "timer.h"

volatile uint32_t timestamp;
volatile uint16_t milliseconds;

ISR(TIMER0_OVF_vect) {
	TCNT0 = 6; //Preload for 250 ticks to overflow

	milliseconds++;
	if(milliseconds > 999) {
		timestamp++;
		milliseconds = 0;
	}
}