#define DIR_PIN 2
#define STEP_PIN 4
#define DELAY_US 2000
#define MS1_PIN 15
#define MS2_PIN 19

void setup()
{
  pinMode(DIR_PIN, OUTPUT);
  pinMode(STEP_PIN, OUTPUT);
  delay(1000);
}

void loop()
{
  digitalWrite(DIR_PIN, HIGH);
  for (int i = 0; i< 200; i++)
{
  digitalWrite(STEP_PIN, HIGH);
  delayMicroseconds(DELAY_US);
  digitalWrite(STEP_PIN, LOW);
  delayMicroseconds(DELAY_US);
}
delay(1000);

digitalWrite(DIR_PIN, LOW);
for (int i = 0; i < 200; i++)
{
  digitalWrite(STEP_PIN, HIGH);
  delayMicroseconds(DELAY_US);
  digitalWrite(STEP_PIN, LOW);
  delayMicroseconds(DELAY_US);
}
delay(1000);
{
  delay(1000);
   digitalWrite(DIR_PIN, LOW);
   for (int i = 0; i < 200; i++) {
   digitalWrite(STEP_PIN, HIGH);
   delayMicroseconds (DELAY_US);
   digitalWrite(STEP_PIN, LOW);
   delayMicroseconds(DELAY_US);
  }
  delay(1000);
}  
}