TCCR2A = 1<<WGM21; // prescaler 1:1024, WGM = 2 (CTC)
TCCR2B = 1<<CS22 | 1<<CS21 | 1<<CS20; //
OCR2A = 155; // (1+155)*1024 = 159744 -> ~10 ms @ 16 MHz
TCCR2A = 1<<WGM21; // prescaler 1:1024, WGM = 2 (CTC)
TCCR2B = 1<<CS22 | 1<<CS21 | 1<<CS20; //
OCR2A = 155; // (1+155)*1024 = 159744 -> ~10 ms @ 16 MHz