Project-ON7532

#define SENSOR_PIN_1  6
#define SENSOR_PIN_2  7
#define STEPPER_PIN_1 9
#define STEPPER_PIN_2 10
#define STEPPER_PIN_3 11
#define STEPPER_PIN_4 12

int step_number = 0;

void setup() {
  Serial.begin(9600);
  pinMode(SENSOR_PIN_1,  INPUT);
  pinMode(SENSOR_PIN_2,  INPUT);
  pinMode(STEPPER_PIN_1, OUTPUT);
  pinMode(STEPPER_PIN_2, OUTPUT);
  pinMode(STEPPER_PIN_3, OUTPUT);
  pinMode(STEPPER_PIN_4, OUTPUT);
}

void loop() {

  if (digitalRead(SENSOR_PIN_1) == 0 && digitalRead(SENSOR_PIN_2) == 1 ) {
    OneStep(true);
    delay(2);
  }
  else if (digitalRead(SENSOR_PIN_2) == 0 && digitalRead(SENSOR_PIN_1) == 1) {
    OneStep(false);
    delay(2);
  }
  else {
    digitalWrite(STEPPER_PIN_1, LOW);
    digitalWrite(STEPPER_PIN_2, LOW);
    digitalWrite(STEPPER_PIN_3, LOW);
    digitalWrite(STEPPER_PIN_4, LOW);
  }

}//end of LOOP


void OneStep(bool dir) {
  if (dir) {
    switch (step_number) {
      case 0:
        digitalWrite(STEPPER_PIN_1, HIGH);
        digitalWrite(STEPPER_PIN_2, LOW);
        digitalWrite(STEPPER_PIN_3, LOW);
        digitalWrite(STEPPER_PIN_4, LOW);
        break;
      case 1:
        digitalWrite(STEPPER_PIN_1, LOW);
        digitalWrite(STEPPER_PIN_2, HIGH);
        digitalWrite(STEPPER_PIN_3, LOW);
        digitalWrite(STEPPER_PIN_4, LOW);
        break;
      case 2:
        digitalWrite(STEPPER_PIN_1, LOW);
        digitalWrite(STEPPER_PIN_2, LOW);
        digitalWrite(STEPPER_PIN_3, HIGH);
        digitalWrite(STEPPER_PIN_4, LOW);
        break;
      case 3:
        digitalWrite(STEPPER_PIN_1, LOW);
        digitalWrite(STEPPER_PIN_2, LOW);
        digitalWrite(STEPPER_PIN_3, LOW);
        digitalWrite(STEPPER_PIN_4, HIGH);
        break;
    }
  } else {
    switch (step_number) {
      case 0:
        digitalWrite(STEPPER_PIN_1, LOW);
        digitalWrite(STEPPER_PIN_2, LOW);
        digitalWrite(STEPPER_PIN_3, LOW);
        digitalWrite(STEPPER_PIN_4, HIGH);
        break;
      case 1:
        digitalWrite(STEPPER_PIN_1, LOW);
        digitalWrite(STEPPER_PIN_2, LOW);
        digitalWrite(STEPPER_PIN_3, HIGH);
        digitalWrite(STEPPER_PIN_4, LOW);
        break;
      case 2:
        digitalWrite(STEPPER_PIN_1, LOW);
        digitalWrite(STEPPER_PIN_2, HIGH);
        digitalWrite(STEPPER_PIN_3, LOW);
        digitalWrite(STEPPER_PIN_4, LOW);
        break;
      case 3:
        digitalWrite(STEPPER_PIN_1, HIGH);
        digitalWrite(STEPPER_PIN_2, LOW);
        digitalWrite(STEPPER_PIN_3, LOW);
        digitalWrite(STEPPER_PIN_4, LOW);


    }
  }
  step_number++;
  if (step_number > 3) {
    step_number = 0;
  }
}