// A4988 Stepper Driver Demo

const int stepPin = 3;
const int dirPin = 4;

const int stepsPerRev = 200; // typical for 1.8° stepper motor

void setup() {
  pinMode(stepPin, OUTPUT);
  pinMode(dirPin, OUTPUT);

  digitalWrite(dirPin, HIGH); // initial direction
}

void loop() {

  // 1. Slow continuous rotation (forward)
  digitalWrite(dirPin, HIGH);
  for (int i = 0; i < stepsPerRev; i++) {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(1200);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(1200);
  }
  delay(1000);

  // 2. Reverse direction fast
  digitalWrite(dirPin, LOW);
  for (int i = 0; i < stepsPerRev; i++) {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(600);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(600);
  }
  delay(1000);

  // 3. Burst stepping (jerky movement demo)
  digitalWrite(dirPin, HIGH);
  for (int i = 0; i < 50; i++) {
    digitalWrite(stepPin, HIGH);
    delay(5);
    digitalWrite(stepPin, LOW);
    delay(5);
  }
  delay(1000);

  // 4. Micro-stepping slow crawl
  digitalWrite(dirPin, LOW);
  for (int i = 0; i < stepsPerRev; i++) {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(2000);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(2000);
  }

  delay(2000);
}