#include <Servo.h>

Servo myServo;
unsigned long MOVING_TIME = 3000; 
unsigned long moveStartTime;
int startAngle = 0;
int stopAngle  = 90;
bool servoStav = false;

void setup() {
  myServo.attach(9);
  moveStartTime = millis(); 
  Serial.begin(9600);


}

void loop() {
  unsigned long progress = millis() - moveStartTime;

  if (progress <= MOVING_TIME) {
    long angle = map(progress, 0, MOVING_TIME, startAngle, stopAngle);
    myServo.write(angle);
    Serial.println(angle); 
  } 
  if (progress >= MOVING_TIME) {
    servoStav = !servoStav;
    if (servoStav) {
      startAngle = 90;
      stopAngle  = 0;}
  else {
    startAngle = 0;
    stopAngle  = 90;
  }
   moveStartTime = millis();
  }
}