#define encoder0PinA 2
#define encoder0PinB 3
#define encoder0Btn 4
#define RC PI / 180
int encoder0Pos = 0;
int rotcheck = 0;
int degree = 1;
double radian =0;
double sine =0;
double cosine = 0;
double tangent = 0;
#include <LiquidCrystal.h>;
const int rs = 12, en = 11, d4 = 10, d5 = 9, d6 = 8, d7 = 7;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
void setup() {
  Serial.begin(9600);
  pinMode(encoder0PinA, INPUT_PULLUP);
  pinMode(encoder0PinB, INPUT_PULLUP);
  pinMode(encoder0Btn, INPUT_PULLUP);
  attachInterrupt(0, doEncoder, CHANGE);
  lcd.begin(16, 2);

}
int valRotary,lastValRotary;
void loop() {

  //start encoder check function
  int btn = digitalRead(encoder0Btn);
  
  //define degreese radians sin cos and tan
  degree = (valRotary * 22.5);
  radian = (degree * RC);
  sine = (sin(radian));
  cosine = (cos(radian));
  tangent = (sine / cosine);

//print degreese
  lcd.setCursor(0, 0);
  lcd.print("Deg:");
  lcd.setCursor(4, 0);
  lcd.print(degree);

//print Radians
  lcd.setCursor(9, 0);
  lcd.print("Rad:");
  lcd.setCursor(13, 0);
  lcd.print(radian,2);

//print sine
  lcd.setCursor(0, 1);
  lcd.print("S:");
  lcd.setCursor(2, 1);
  lcd.print(sine,3);

//print cos
  lcd.setCursor(8, 1);
  lcd.print("C:");
  lcd.setCursor(10, 1);
  lcd.print(cosine,3);

//print tan
  if (rotcheck != valRotary) {
    rotcheck = valRotary;
    Serial.print(rotcheck);
    lcd.clear();

  }
}


//read encoder 
void doEncoder()
{
  if (digitalRead(encoder0PinA) == digitalRead(encoder0PinB))
  {
	encoder0Pos++;
  }
  else
  {
	encoder0Pos--;
  }
  valRotary = abs(encoder0Pos/2.5);
}