#include <ESP32Servo.h>
#define servopin 26
int angle, direction = -1;

Servo servoMotor;

void setup() {
  Serial.begin(115200);
  servoMotor.attach(servopin);
}

void loop() {
  if (angle <= 0 || angle >= 180) // if outside bounds...
    direction = -direction; // ... change direction
  angle += direction; // increment/decrement
  servoMotor.write(angle); // write angle to servo
  delay(10); // wait for servo
  Serial.println(angle);
}