R1

// Sharp IR GP2Y0A41SK0F Distance Test
// http://tinkcore.com/sharp-ir-gp2y0a41-skf/

#define sensor A0 // Sharp IR GP2Y0A41SK0F (4-30cm, analog)
#include <LiquidCrystal.h>

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
bool tombol;

void setup() {
  Serial.begin(9600); // start the serial port
  pinMode(8, INPUT_PULLUP);
  tombol = digitalRead (8);
}

void loop() {
  tombol = 0;
  tombol = digitalRead(8); // baca pushbutton value
  // kondisi awal saat power on belum dipencet tombol
    lcd.begin (16,2);
    lcd.print ("Posisikan valve pada");
    lcd.setCursor (3,1);
    lcd.print ("Full Open");


  delay(500);
  if (tombol == LOW) {// pencet tombol satu kali
    tombol = 0;
    int rata2, persen, var;
    float fo, fc, volts,distancefo, distance;
    rata2 = 0;

    for (int i=0; i<200; i++) {// mendeteksi variable FO
      lcd.begin(16,2);
      lcd.setCursor (2,0);
      lcd.print ("Mendeteksi");
      lcd.setCursor (3,1);
      lcd.print ("Full Open");

      volts = analogRead(sensor)*0.0048828125;  // value from sensor * (5/1024)
      distancefo = 13*pow(volts, -1)-1; // worked out from datasheet graph
      rata2 = rata2 + distancefo;
      delay (25); // tunggu 25 ms each read
      distancefo = rata2/200;
      fo = distancefo;
    }
  }
  while (tombol==LOW){// selesei deteksi FO tampilkan ini
    lcd.begin(16,2);
    lcd.print("posisikan FC");
    tombol++;
  }
   if (tombol==0){// kondisi mengukur FC persen bukaan setelah dapat nilai FO


      int rata2, persen, var;
      float fo, fc, volts,distancefc, distance;
      rata2 = 0;

    for (int j=0; j<200; j++) {// mendeteksi variable FC
      lcd.begin(16,2);
      lcd.setCursor (2,0);
      lcd.print ("Mendeteksi");
      lcd.setCursor (3,1);
      lcd.print ("Full Close");

      volts = analogRead(sensor)*0.0048828125;  // value from sensor * (5/1024)
      distancefc = 13*pow(volts, -1)-1; // worked out from datasheet graph
      rata2 = rata2 + distancefc;
      delay (25); // tunggu 25 ms each read
      distancefc = rata2/200;
      fc = distancefc;
    }
    }
    while (tombol==0) {// selesei dapat FO, tampilkan pengukuran pembukaan valvenya
      int rata2, persen, var;
    float fo, fc, volts,distancefo, distance;
    rata2 = 0;
      volts = analogRead(sensor)*0.0048828125;  // value from sensor * (5/1024)
      distance = 13*pow(volts, -1)-1; // worked out from datasheet graph
      persen = (distance-fc)/(fo-fc)*100;
      delay (500);
      if (persen >100){
         lcd.begin (16,2);
        lcd.print (" Pembukaan valve");
        lcd.setCursor (6,1);
        lcd.print ("100%");
      }
      else if (persen <0){
        lcd.begin (16,2);
        lcd.print (" Pembukaan valve");
        lcd.setCursor (6,1);
        lcd.print ("0%");
      }
      else {
      lcd.begin (16,2);
      lcd.print (" Pembukaan valve");
      lcd.setCursor (6,1);
      lcd.print (persen);
      lcd.print ("%");

      tombol++;
    }
}
}