/* Turn on or off an alarm by passing a shadow over the light sensor */
int shadowCount = 0; //Variable keeping track of the shadows that cross the light sensor
void setup() {
pinMode(A2,INPUT); //light sensor
pinMode(A5,OUTPUT); //speaker
Serial.begin(9600); //set up the serial monitor
}
void loop() {
if(analogRead(A2)<4){ //if the light sensor reading is below 4...
shadowCount++; //increase the value of the shadow count variable by 1
delay(500); //pause 500 milliseconds (half a second)
}
if(shadowCount == 1){ //if the shadow count variable equals 1...
tone(A5,500); // start playing a tone of 500 hertz
delay(100); //delay 100 milliseconds
tone(A5,1000); //play a tone of 1000 hertz
delay(100); //delay 100 milliseconds
}
else{ //otherwise, if the shadow count variable doesn't equal 1...
noTone(A5);
shadowCount = 0; //set the variable equal to 0.
}
Serial.println(analogRead(A2)); //show the value of the analogRead the light sensor
}
// (c) 2024 Let's Start Coding. License: www.letsstartcoding.com/bsdlicense
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