       TCCR2A = 1<<COM2A0 | 0<<COM2B0 | 2<<WGM20; // Toggle OC2A on match
     } else error(F("'note' pin not supported"));
     int prescaler = 0;
-    if (cdr(cdr(args)) != NULL) prescaler = integer(third(args));
+    if (cddr(args) != NULL) prescaler = integer(third(args));
     prescaler = 9 - prescaler - note/12;
     if (prescaler<3 || prescaler>6) error(F("'note' octave out of range"));
     OCR2A = pgm_read_byte(&scale[note%12]);

      printobject(form);
    }
    Serial.print(')');
  } else if (form->type == NUMBER){
    Serial.print(integer(form));
  } else if (form->type == SYMBOL){
    Serial.print(name(form));
  } else
    error(F("Error in print."));
}


#define first(x)           (((object *) (x))->car)
#define second(x)          (car(cdr(x)))
#define cddr(x)            (cdr(cdr(x)))
#define third(x)           (car(cdr(cdr(x))))
#define fourth(x)          (car(cdr(cdr(cdr(x)))))

