Sine Stepper

const int pulPin = 2;
const int enaPin = 1;
const int dirPin = 0;
float sinCounter = 0.0;

void setup() {
  pinMode(pulPin, OUTPUT);
  pinMode(dirPin, OUTPUT);
  pinMode(enaPin, OUTPUT);

  digitalWriteFast(enaPin, LOW); 
  digitalWriteFast(dirPin, HIGH);
}

void loop() {
  float frequencyFloat = sinf(sinCounter) * 10.0f;
  //float frequencyFloat = -5.5;      //This line works to give a output frequency of 5.
  int frequencyInt = abs(frequencyFloat);
  tone(pulPin, frequencyInt);
  Serial.println(frequencyInt);
  sinCounter += 0.05;
  if(sinCounter > 6.28318530718) 
    sinCounter = 0;
  delay(100);
}