#define DIR_PIN  2
#define STEP_PIN 4
#define MS1_PIN 15
#define MS2_PIN 0
#define DELAY_US 2000
void setup() {
 pinMode(MS1_PIN, OUTPUT);
 pinMode (STEP_PIN, OUTPUT);
 delay (1000);
}
void loop() {
 digitalWrite(MS1_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);
   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);
}