#include<ESP32Servo.h>
Servo myservo;                                       
int angle = 0;                                           
void setup()
{
myservo.attach(4,544,2400);  
Serial.begin(115200);                                      
}
void loop()
{
for(angle = 0; angle < 180; angle += 1)              
{                                                                                
myservo.write(angle);                                          
delay(20);                                                    
}
for(angle = 180; angle >= 1; angle -= 1)      
{
myservo.write(angle);                                            
delay(20);           
Serial.print("angle: ");
Serial.println(angle);                                                     
}
}