#include <Servo.h>

Servo arm; // Create a "Servo" object called "arm"
float pos = 0.0; // Variable where the arm's position will be stored (in degrees)
float step = 1.0; // Variable used for the arm's position step
int lvl = 0;

#define LED 6
#define SERV 2

void setup() {
  // put your setup code here, to run once:
  pinMode(LED, OUTPUT);
  pinMode(A1, INPUT_PULLUP);
  arm.attach(SERV);
  arm.write(pos);
}

void loop() {
  // put your main code here, to run repeatedly:
  lvl = digitalRead(A1) ? LOW : HIGH;
  digitalWrite(LED, lvl);
  if (!digitalRead(A1)) {
    if (pos < 1) step = 1.0;
    if (pos > 179) step = -1.0;
    pos += step;
    arm.write(pos);
    delay(5);
  }
}