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SPlaying tones on Multiple outputs using the tone() function

This example shows how to use the tone() command to play different notes on multiple outputs.

The tone() command works by taking over one of the Atmega's internal timers, setting it to the frequency you want, and using the timer to pulse an output pin. Since it's only using one timer, you can only play one note at a time. You can, however, play notes on multiple pins sequentially. To do this, you need to turn the timer off for one pin before moving on to the next.

Thanks to Greg Borenstein for clarifying this.

Hardware Required

  • (3) 8-ohm speakers
  • (3) 100 ohm resistor
  • breadboard
  • hook up wire

Circuit

image developed using Fritzing. For more circuit examples, see the Fritzing project page

Schematic

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Code

The sketch below plays a tone on each of the speakers in sequence, turning off the previous speaker first. Note that the duration of each tone is the same as the delay that follows it.

Here's the main sketch:

/*
  Multiple tone player
 
 Plays multiple tones on multiple pins in sequence
 
 circuit:
 * 3 8-ohm speaker on digital pins 6, 7, and 8
 
 created 8 March 2010
 by Tom Igoe
 based on a snippet from Greg Borenstein

This example code is in the public domain.
 
 http://arduino.cc/en/Tutorial/Tone4
 
 */


void setup() {

}

void loop() {
  // turn off tone function for pin 8:
  noTone(8);           
  // play a note on pin 6 for 200 ms:
  tone(6, 440, 200);
  delay(200);

  // turn off tone function for pin 6:
  noTone(6);
  // play a note on pin 7 for 500 ms:
  tone(7, 494, 500);
  delay(500);
 
  // turn off tone function for pin 7:
  noTone(7);  
  // play a note on pin 8 for 500 ms:
  tone(8, 523, 300);
  delay(300);
}

See Also:

  • tone()

  • Tone - play a melody with a piezo speaker
  • Pitch follower - play a pitch on a piezo speaker depending on an anlog input.
  • Tone 3 - a three-key musical keyboard using force sensors

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