sketch sensore distanza per Arduino con suono

// sketch sensore distanza per ARDUINO UNO con indicatore sonoro#define TRIG_PIN 10#define ECHO_PIN 9#define sound_pin 7 void setup() {Serial.begin(9600);pinMode(sound_pin, OUTPUT);pinMode(TRIG_PIN, OUTPUT);pinMode(ECHO_PIN, INPUT);digitalWrite(TRIG_PIN, LOW);}void loop() {digitalWrite(TRIG_PIN, HIGH);delayMicroseconds(10);digitalWrite(TRIG_PIN, LOW);int tempo = pulseIn(ECHO_PIN, HIGH);int distanza = 0.03438 * tempo /2;  tone(sound_pin,500,30);  delay(10*distanza);delay (10);}