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

LiquidCrystal_I2C lcd(0x27,20,4);  
 
 #define outputA 4
 #define outputB 5
 int S0 = 7;
 int S1 = 8;
 int S2 = 9;
 int S3 = 10;
 int muxCh = 0;
 int dutyCode = 0; 
 int aState;
 int aLastState;
 int outPwm = 9; // the PWM pin the motor is attached
 int menu1 = 1;
 int menu2 = 1;
 int outputBstate;
 int outputBLaststate;
 int statusoutputB;
 int laststatusoutputB;
 int count1 = 0;
 float convertion = 0;
 
 void setup() { 
   pinMode (outputA,INPUT);
   pinMode (outputB,INPUT);
   pinMode (outPwm, OUTPUT);
   pinMode (S0, OUTPUT);
   pinMode (S1, OUTPUT);
   pinMode (S2, OUTPUT);
   pinMode (S3, OUTPUT);
   lcd.init();                      // initialize the lcd 
   lcd.init();
   // Print a message to the LCD.
   lcd.backlight();
   
   Serial.begin (9600);
   // Reads the initial state of the outputA
   aLastState = digitalRead(outputA);   
 } 

 void loop() { 
   aState = digitalRead(outputA); // Reads the "current" state of the outputA
   // If the previous and the current state of the outputA are different, that means a Pulse has occured
   if (aState != aLastState){     
     // If the outputB state is different to the outputA state, that means the encoder is rotating clockwise
     if (digitalRead(outputB) != aState) { 
       dutyCode ++;
     } else {
       dutyCode --;
     }
     
    if (dutyCode < 0) {
      (dutyCode = 0);
    } 
     if (dutyCode > 255) {
      (dutyCode = 255);
    }
     analogWrite(outPwm, dutyCode);
     lcd.setCursor(0,0);
     int DTC = (dutyCode*100)/255;
     lcd.print(DTC);
     lcd.setCursor(3,0);
     lcd.print("%");
     if (DTC < 10) { 
      lcd.setCursor(1,0);
      lcd.print(" ");
     }
     if (DTC < 100) { 
      lcd.setCursor(2,0);
      lcd.print(" ");
     }
     Serial.print("dutyCode: ");
     Serial.println(dutyCode);
     
   } 
   aLastState = aState; // Updates the previous state of the outputA with the current state
}