unsigned int adc(void){

		 unsigned int adwert=0;
		
		 ADCSRA =0b10000110;	   //ADC-aktivieren, single mode,Prescaler=64=>Conversion-Time:125kHz
		 ADMUX  =0b11000000;	   //intern 2,56V an ADC-V-REF,result right adjust
		 			   //ADC0-PORT,Single-ended
		 
		 ADCSRA|=0b01000000;	   //AD-Wandlung starten
		 while((ADCSRA & 0b01000000)!=0){}//Abfrage ob Conversion Complete
		 adwert=((ADCH<<8)+ADCL);  //ADC-Wert berechnen
		 
		 ADCSRA =0b00000110;	   //ADC deaktivieren
		 return adwert;		   //ADC-Rückgabewert
	}