/*---------------------------------------*\
| Simple direct drive of Bipolar Stepper  |
\*---------------------------------------*/

// pins connected
#define Ap 10  // A+ line
#define Am 11  // A- line
#define Bp 9   //  .
#define Bm 8   //  .
#define DT 50
#define DT2 5
#define STEPS 50

void setup() {
  // set output
  pinMode(Ap,OUTPUT);  pinMode(Am,OUTPUT);
  pinMode(Bp,OUTPUT);  pinMode(Bm,OUTPUT);
  digitalWrite(Ap,LOW) ;  digitalWrite(Bp,LOW);
  digitalWrite(Am,LOW) ;  digitalWrite(Bm,LOW);

  for (int i = 0; i < STEPS; i++) {
	digitalWrite(Bm,LOW) ;  digitalWrite(Ap,HIGH);
    delay(DT);
    digitalWrite(Ap,LOW) ;  digitalWrite(Bp,HIGH);
    delay(DT);
    digitalWrite(Bp,LOW) ;  digitalWrite(Am,HIGH);
    delay(DT);
    digitalWrite(Am,LOW) ;  digitalWrite(Bm,HIGH);
	delay(DT);
  }
  for (int i = 0; i < STEPS; i++) {
	digitalWrite(Bp,LOW) ;  digitalWrite(Am,HIGH);
    delay(DT2);
	digitalWrite(Ap,LOW) ;  digitalWrite(Bp,HIGH);
    delay(DT2);
	digitalWrite(Bm,LOW) ;  digitalWrite(Ap,HIGH);
    delay(DT2);
	digitalWrite(Am,LOW) ;  digitalWrite(Bm,HIGH);
	delay(DT2);
  }
}

void loop() {
}