#define DIR_PIN 2
#define STEP_PIN 4
#define DELAY_US 2000

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);
}