timer.h:

namespace timer
{	
	class timer_8
	{
		public:
			static void init(uint8_t tccr0)
			{
				cbi(TIMSK, TOIE0);
				TCCR0 = tccr0;
			}
			
			static void call(uint8_t cycles, void (*function)())
			{
				m_func = function;
				
				TCNT0 = (255 - (cycles-1));
				sbi(TIMSK, TOIE0);
			}
		
		
			static void _exec()
			{
				cbi(TIMSK, TOIE0);
				(*m_func)();
			}
			
				
		private:
			static void (*m_func)();
	};
}


timer.cpp:
#include "D:/projects/AVR/libs/timer.h"

void timer::timer_8::init(uint8_t tccr0)
{
	cbi(TIMSK, TOIE0);
	TCCR0 = tccr0;
}

void timer::timer_8::call(uint8_t cycles, void (*function)())
{
	m_func = function;
	
	TCNT0 = (255 - (cycles-1));
	sbi(TIMSK, TOIE0);
}


void timer::timer_8::_exec()
{
	cbi(TIMSK, TOIE0);
	(*m_func)();
}
			
void (*timer_8::m_func)() = NULL;