//Stepper Board Test Code
//Kevin Darrah  2017

#include <Wire.h> 
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x20,16,2);

const int stepPin = 2;//only works on this pin right now
const int dirPin = 6;
const int actPin = 4;//not used
const float motorAngle = 1.8;
const float stepSize = 1;//full=1, half=0.5, quarter=0.25, etc...


void stepperRotate(float rotation, float rpm);

void setup() {
  // put your setup code here, to run once:
  pinMode(stepPin, OUTPUT);
  pinMode(dirPin, OUTPUT);
  //pinMode(actPin, OUTPUT);  hooked to VCC, so no Arduino control
  Serial.begin(9600);
  lcd.init();
  lcd.backlight();
  delay(5000);
  lcd.clear();
  lcd.home();
  lcd.print(" IoT Pet Treat");
  lcd.setCursor(0,1);
  lcd.print("   Dispenser");

}

void loop() {
  if(Serial.available()>0){
    String data = Serial.readStringUntil('\n');
    if(data=="D"){
      lcd.clear();
      lcd.home();
      lcd.print("Dispensing");
      lcd.setCursor(0,1);
      lcd.print("treats now.");
      stepperRotate(.5, 30);//rotations, RPM
      delay(500);
      stepperRotate(-.2, 30);//rotations, RPM
      delay(3000);
      lcd.clear();
      lcd.home();
      lcd.print(" IoT Pet Treat");
      lcd.setCursor(0,1);
      lcd.print("   Dispenser");
    }
  }
  delay(1500);

}

void stepperRotate(float rotation, float rpm) {
  if (rotation > 0) {
    digitalWrite(dirPin, HIGH);
  }
  else {
    digitalWrite(dirPin, LOW);
    rotation = rotation * -1;
  }

  float stepsPerRotation = 1050;

  //now we have the steps per rotation, multiply by the rotations for this command to get total steps
  float totalSteps = rotation * stepsPerRotation;

  unsigned long stepPeriodmicroSec = ((60.0000 / (rpm * stepsPerRotation)) * 1E6 / 2.0000) - 5;

  for (unsigned long i = 0; i < totalSteps; i++) {
    PORTD |= (1 << 2);
    delayMicroseconds(stepPeriodmicroSec);
    PORTD &= ~(1 << 2);
    delayMicroseconds(stepPeriodmicroSec);
  }

}