const int umbralminimo = 10; 
int notas[] = { 220, 440, 880 }; 

void setup(){}

void loop() {
    int i;
    int lectura;
    for (i = 0; i < 3; i++) {
         lectura = analogRead(i);
         if (lectura > umbralminimo) {
               tone(8, notas[i], 20);
         } 
    }
}





