const float pi = 3.14159;
const int DirPin = 8;
const int StepPin = 9;  
const int EndPin = 2; // the pin for the button sensors
const int startPin = 3;
float initializeSpeed = 0.005; // the linear speed of the motor (m/s)
int stepCount;
int currentStep;
int totalStepLength;

void setup() {
pinMode(StepPin, OUTPUT);
pinMode(DirPin, OUTPUT);
pinMode(EndPin, INPUT);
pinMode(startPin, INPUT);
Serial.begin(9600);

initialize();

Serial.print("Total Step Count= ");
Serial.println(totalStepLength);
delay(500);
Serial.print("current Step= ");
Serial.println(currentStep);

}
void loop() {

}


// This is the first function used in the set up process
// it used the button sensors to measure the length of the 
// track in "step" units. 
void initialize() {
  float pulse = (((2*pi*0.008*0.005)/initializeSpeed)/2)*1e6;
  Serial.print("pulse time = ");
  Serial.print(pulse);
  Serial.println(" x 10^-6");

  // this section of code could be used to have the program wait till a button is pressed
  while (digitalRead(startPin) == LOW) { 
  }

  // move the stepper clockwise until the first button is clicked 
  while (digitalRead(EndPin) == LOW) { 
    digitalWrite(DirPin, HIGH); 
    digitalWrite(StepPin, HIGH);
    delayMicroseconds(pulse);
    digitalWrite(StepPin, LOW);
    delayMicroseconds(pulse);
  }
  
  delay(500);

 // move the stepper counter-clockwise until the second  
 // button is clicked while counting steps for the 
 // total length of the track  
  while (digitalRead(EndPin) == LOW) {
    digitalWrite(DirPin, LOW); 
    digitalWrite(StepPin, HIGH);
    delayMicroseconds(pulse);
    digitalWrite(StepPin, LOW);
    delayMicroseconds(pulse);
    stepCount++; 
  }

 // update global variables for total step length
 // and calculate middle position in "step" units
  delay(500);
  totalStepLength = stepCount;
  int middlePos = totalStepLength/2;
  Serial.print("middle position steps= ");
  Serial.println(middlePos);
  stepCount = 0;  // reseting step count to make endpoint new starting point
  currentStep = stepCount;

 // moving bed to center & update current step location
  for(int x = 0; x < middlePos; x++) {
    digitalWrite(DirPin, HIGH); 
    digitalWrite(StepPin, HIGH);
    delayMicroseconds(pulse);
    digitalWrite(StepPin, LOW);
    delayMicroseconds(pulse);
    currentStep++;
  }
}