#include <ESP32Servo.h>
#define buzz 18

const int echo = 21;
const int trig = 19;
const int servoPin = 15;

Servo myservo;
int pos = 0;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  myservo.attach(servoPin, 500, 2400);
  pinMode(buzz, OUTPUT);
  pinMode(echo, OUTPUT);
  pinMode(trig, INPUT);
}

void loop() {
  for (pos = 0; pos <= 180; pos += 1) {
    myservo.write(pos);
    delay(15);
  }
  for (pos = 180; pos >= 0; pos -= 1) {
    myservo.write(pos);
    delay(15);
  }
}