// fast PWM Mode 7 Timer0

	TCCR0A = (1 << COM0A1) | (1 << WGM01) | (1 << WGM00);
	TCCR0B = (1 << WGM02) | (1 << CS01);				// clock source = CLK/8, start PWM
	OCR0A = 52;							// Timer Top-Wert für 100Hz	

	OCR0B = PWM_50;						// initial PWM pulse width	?