#include <Servo.h>

Servo arm;
int motorPin = 3;
int buttonUp = 5;
int buttonDown = 4;
int pos = 0;
int step = 1;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  arm.attach(motorPin);
  arm.write(pos);
  pinMode(buttonUp, INPUT_PULLUP);
  pinMode(buttonDown, INPUT_PULLUP);
}

void loop() {
  // put your main code here, to run repeatedly:

  if(digitalRead(buttonDown) == 0) { // oder False oder LOW
    if (pos < 180) {
      arm.write(pos);
      pos += step; // pos = pos + step
      delay(5);
    }
  }
  // Alternative: if(!digitalRead(buttonUp))
  if(digitalRead(buttonUp) == 0) {// oder False oder LOW
    if (pos > 0) {
      arm.write(pos);
      pos -= step;  // pos = pos - step
      delay(5);
    }
  }
  Serial.println(pos);
  //for (pos = 0; pos <= 180; pos++) {
  //  arm.write(pos);
  //  delay(100);
  //}

  //delay(500);

  //for (pos = 180; pos >= 0; pos--) {
  //  arm.write(pos);
  //  delay(100);
  //}

}