数字制造讲义08-Arduino声音应用2

// connect a potentiometer to pin A0
 
int buzzerPin=8;
int potPin=A0;
 
void setup() {
  pinMode(buzzerPin, OUTPUT);
}
 
void loop() {
  int freq = analogread(A0);
  freq = map (freq,0,1023,20,20000); //map the value read from the potentiometer into the audible range
  tone (buzzerPin,freq);
}

/*
  Melody
 
  Plays a melody
 
  circuit:
  - 8 ohm speaker on digital pin 8
 
  created 21 Jan 2010
  modified 30 Aug 2011
  by Tom Igoe
 
  This example code is in the public domain.
 
  http://www.arduino.cc/en/Tutorial/Tone
*/
 
#include "pitches.h"
 
// notes in the melody:
int melody[] = {
  NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3, 0, NOTE_B3, NOTE_C4
};
 
// note durations: 4 = quarter note, 8 = eighth note, etc.:
int noteDurations[] = {
  4, 8, 8, 4, 4, 4, 4, 4
};
 
void setup() {
  // iterate over the notes of the melody:
  for (int thisNote = 0; thisNote < 8; thisNote++) {
 
    // to calculate the note duration, take one second divided by the note type.
    //e.g. quarter note = 1000 / 4, eighth note = 1000/8, etc.
    int noteDuration = 1000 / noteDurations[thisNote];
    tone(8, melody[thisNote], noteDuration);
 
    // to distinguish the notes, set a minimum time between them.
    // the note's duration + 30% seems to work well:
    int pauseBetweenNotes = noteDuration * 1.30;
    delay(pauseBetweenNotes);
    // stop the tone playing:
    noTone(8);
  }
}
 
void loop() {
  // no need to repeat the melody.
}