Buzzer

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Specification

Passive buzzer

Passive buzzers don’t do anything themselves – the software needs to generate a waveform for any sound it wants to make. This example code uses PWM timings to play different notes – your buzzer should be connected to pin 9. Alternatively, take a look at the tone() function.

 
 
/* Play Melody
 * -----------
 *
 * Program to play melodies stored in an array, it requires to know
 * about timing issues and about how to play tones.
 *
 * The calculation of the tones is made following the mathematical
 * operation:
 *
 *       timeHigh = 1/(2 * toneFrequency) = period / 2
 *
 * where the different tones are described as in the table:
 *
 * note         frequency       period  PW (timeHigh)   
 * c            261 Hz          3830    1915    
 * d            294 Hz          3400    1700    
 * e            329 Hz          3038    1519    
 * f            349 Hz          2864    1432    
 * g            392 Hz          2550    1275    
 * a            440 Hz          2272    1136    
 * b            493 Hz          2028    1014    
 * C            523 Hz          1912    956
 *
 * (cleft) 2005 D. Cuartielles for K3
 */
 
int ledPin = 13;
int speakerOut = 9;               
byte names[] = {'c', 'd', 'e', 'f', 'g', 'a', 'b', 'C'};  
int tones[] = {1915, 1700, 1519, 1432, 1275, 1136, 1014, 956};
byte melody[] = "2d2a1f2c2d2a2d2c2f2d2a2c2d2a1f2c2d2a2a2g2p8p8p8p";
// count length: 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
//                                10                  20                  30
int count = 0;
int count2 = 0;
int count3 = 0;
int MAX_COUNT = 24;
int statePin = LOW;
 
void setup() {
 pinMode(ledPin, OUTPUT); 
}
 
void loop() {
	analogWrite(speakerOut, 0);     
	for (count = 0; count < MAX_COUNT; count++) {
		statePin = !statePin;
		digitalWrite(ledPin, statePin);
		for (count3 = 0; count3 <= (melody[count*2] - 48) * 30; count3++) {
			for (count2=0;count2<8;count2++) {
				if (names[count2] == melody[count*2 + 1]) {       
					analogWrite(speakerOut,500);
					delayMicroseconds(tones[count2]);
					analogWrite(speakerOut, 0);
					delayMicroseconds(tones[count2]);
				} 
				if (melody[count*2 + 1] == 'p') {
					// make a pause of a certain size
					analogWrite(speakerOut, 0);
					delayMicroseconds(500);
				}
			}
		}
	}
}