#include "Wire.h" //allows communication over i2c devices
#include "LiquidCrystal_I2C.h" //allows interfacing with LCD screens
#define relay1 A2
#define relay2 A3
#define menu 4
#define up 5
#define down 6
#define set 7

//Pressure sensor 1
const int pressureInput1 = A1; //select the analog input pin for the pressure transducer
const int pressureInput2 = A0;
const int pressureZero = 88.064; //analog reading of pressure transducer at 0psi
const int pressureMax = 921.6; //analog reading of pressure transducer at 100psi
const int pressuretransducermaxPSI = 100; //psi value of transducer being used
const int baudRate = 9600; //constant integer to set the baud rate for serial monitor
const int sensorreadDelay = 250; //constant integer to set the sensor read delay in milliseconds

int Ratio_CV[9] = {100 , 90 , 80 , 70 , 60, 50, 40, 30, 20};
int index_ratio=0;

String valve[2] = {"TDV_A" , "TDV_S"};

String model_A[38]= {"50x50" ,"65x65" ,"80x65" ,"80x80" ,"100x65" ,"100x80" ,"100x100",
"125x80" ,"125x100" ,"125x125" ,"150x100" ,"150x125" ,"150x150" ,"200x125" ,"200x150",
"200x200" ,"250x150" ,"250x200" ,"250x250" ,"300x150" ,"300x200" ,"300x250" ,"300x300",
"350x200" ,"350x250" ,"350x300" ,"350x350" ,"400x250" ,"400x300" ,"400x400" ,"450x250",
"450x300" ,"450x450" ,"500x350" ,"500x500" ,"600x600" ,"700x500" ,"700x700"};
int index_A;

String model_S[14]={"50x50" ,"65x65" ,"80x80" ,"100x100" ,"125x125" ,"150x150" ,
"200x200" ,"250x250" ,"300x300", "350x350","400x400","450x450","500x500","600x600"};
int index_S=0;

int CV_A[38][9]=
{
  {75,	72,	67,	60,	52,	45,	36,	27,	18},
  {124,	119,	110,	98,	86,	73,	59,	45,	29},
  {126,	121,	113,	100,	88,	75,	60,	46,	30},
  {172,	165,	153,	136,	120,	102,	82,	63,	41},
  {129,	124,	115,	102,	90,	77,	61,	47,	31},
  {173,	166,	155,	138,	121,	103,	82,	63,	41},
  {364,	350,	325,	290,	255,	217,	173,	133,	87},
  {175,	168,	156,	139,	122,	104,	83,	64,	42},
  {366,	351,	327,	291,	256,	217,	174,	134,	87},
  {526,	505,	470,	418,	368,	313,	250,	193,	125},
  {369,	354,	329,	293,	258,	219,	175,	135,	88},
  {529,	508,	472,	420,	370,	314,	252,	194,	126},
  {831,	798,	742,	660,	581,	494,	395,	304,	198},
  {531,	510,	474,	422,	371,	316,	253,	194,	126},
  {833,	799,	743,	662,	582,	495,	396,	305,	198},
  {1485, 1425,	1325,	1180,	1038,	882,	706,	544,	353},
  {834,	801,	745,	663,	583,	496,	397,	305,	199},
  {1486,	1426,	1326,	1180,	1039,	883,	706,	544,	354},
  {2475,	2376,	2210,	1967,	1731,	1471,	1177,	906,	589},
  {838,	804,	748,	666,	586,	498,	398,	307,	199},
  {1487,	1427,	1327,	1181,	1040,	884,	707,	544,	354},
  {2477,	2378,	2211,	1968,	1732,	1472,	1178,	907,	589},
  {3076,	2953,	2746,	2444,	2151,	1828,	1462,	1126,	732},
  {1487,	1428,	1328,	1182,	1040,	884,	707,	545,	354},
  {2478,	2379,	2213,	1969,	1733,	1473,	1178,	907,	590},
  {3077,	2954,	2747,	2445,	2152,	1829,	1463,	1127,	732},
  {3570,	3427,	3187,	2837,	2496,	2122,	1698,	1307,	850},
  {2479,	2380,	2213,	1970,	1733,	1473,	1179,	908,	590},
  {3080,	2957,	2750,	2447,	2154,	1831,	1464,	1128,	733},
  {4796,	4605,	4282,	3811,	3354,	2851,	2281,	1756,	1141},
  {2482,	2383,	2216,	1972,	1736,	1475,	1180,	909,	591},
  {3081,	2958,	2751,	2448,	2155,	1831,	1465,	1128,	733},
  {6058,	5816,	5408,	4814,	4236,	3601,	2880,	2218,	1442},
  {3576,	3433,	3192,	2841,	2500,	2125,	1700,	1309,	851},
  {7479,	7180,	6677,	5943,	5230,	4445,	3566,	2738,	1780},
  {10770,	10339,	9615,	8558,	7531,	6401,	5121,	3943,	2563},
  {7481,	7182,	6679,	5944,	5231,	4446,	3557,	2739,	1780},
  {15128,	14523,	13506,	12021,	10578,	8991,	7193,	5539,	3600}
};


int CV_S[14][9]=
{
{62,	60,	55,	49,	43,	37,	29,	23,	15},
{90,	86,	80,	72,	63,	53,	43,	33,	21},
{140,	134,	125,	111,	98,	83,	67,	51,	33},
{300,	288,	268,	238,	210,	178,	143,	110,	71},
{428,	411,	382,	340,	299,	254,	204,	157,	102},
{673,	646,	601,	535,	471,	400,	320,	246,	160},
{1200,	1152,	1071,	954,	839,	713,	571,	439,	286},
{2000,	1920,	1786,	1589,	1398,	1189,	951,	732,	476},
{2500,	2400,	2232,	1986,	1748,	1486,	1189,	915,	595},
{2900,	2784,	2589,	2304,	2028,	1724,	1379,	1062,	690},
{3900,	3744,	3482,	3099,	2727,	2318,	1854,	1428,	928},
{5200,	4992,	4643,	4132,	3636,	3091,	2473,	1904,	1237},
{7000,	6720,	6250,	5562,	4895,	4160,	3328,	2563,	1666},
{8800,	8448,	7857,	6992,	6154,	5230,	4184,	3222,	2094}
};


float pressureValue1_psi = 0;
float pressureValue2_psi = 0;
float pressureValue1_bar = 0;
float pressureValue2_bar = 0;
float pressureValue12_psi=0;
float pressureValue12_bar=0;

//set initial values for set point in both bar and PSI
float set_point1_m3_h = 123;
float set_point1_usgpm = 4.403*123;
float set_point2_m3_h = 150;
float set_point2_usgpm = 4.403*150;

float orig_dppsi = 0;
float orig_dpbar = 0;
float flowrate_m3_h = 0.0;
float flowrate_usgpm = 0.0;
int CvValue=0;  // Cv value for the valve
int Ratio=100;
bool first_screen=true;

//custom datatype define to do pressure setting in different units
enum unit_pressure  {psi , bar};
// default unit for pressue
unit_pressure current_unit_P = psi;

//custom datatype define to do pressure setting in different units
enum unit_flow  {m3_h , usgpm};
// default unit for pressue
unit_flow current_unit_F = m3_h;

//defining variables for pressure tracking in both bar and PSI
float flowValue1_psi = 0;
float flowValue1_bar = 0;

float flowValue2_psi = 0;
float flowValue2_bar = 0;


//defining custom data type to track settings that can be modified
enum settings  {set_sp1 , set_sp2 , set_valve , set_model,set_unit_F,set_unit_P};
//defaul arrow position when setting page load
    settings setting_1 = set_sp1;
//temperory values that store values in setting (these can be assigned to original variables if user
// select to save settings)    
    float set_point1m3_h_temp =0;
    float set_point2m3_h_temp =0;
    float set_point1usgpm_temp =0;
    float set_point2usgpm_temp =0;

    float set_point1psi_temp=0;
    float set_point2psi_temp=0;
    float set_point1bar_temp=0;
    float set_point2bar_temp=0; 

    String set_valve_temp;
    String set_model_temp;

    
    unit_flow  temp_unit_F = m3_h;
    unit_pressure  temp_unit_P =psi;
    String temp_F="M3/H";
    String temp_P="PSI";

LiquidCrystal_I2C lcd(0x27, 20, 4); //sets the LCD I2C communication address; format(address, columns, rows)



void setup() //setup routine, runs once when system turned on or reset
{
Serial.begin(baudRate); //initializes serial communication at set baud rate bits per second
lcd.init(); //initializes the LCD screen
//turn on back light
lcd.backlight();
//setting relay pins as output
pinMode(relay1 , OUTPUT);
pinMode(relay2 , OUTPUT);
//setting buttons as input
pinMode(menu , INPUT);
pinMode(up , INPUT);
pinMode(down , INPUT);
pinMode(set , INPUT);

index_A=7;
set_valve_temp = valve[0];
set_model_temp = model_A[0];
Serial.print("VALVE=");
Serial.println(set_valve_temp);
Serial.print("MODEL=");
Serial.println(set_model_temp);
delay(100);
}

void loop() //loop routine runs over and over again forever
{

if(valve[0])
{CvValue=CV_A[index_A][index_ratio];}
else
{CvValue=CV_S[index_S][index_ratio];}

pressure_measurement();
flowrate_m3_h= (sqrt(abs(pressureValue12_psi)) / 1.167) * CvValue;
flowrate_usgpm = (sqrt(abs(pressureValue12_bar)) / 1.167) * CvValue;
//run thbelow lines if flow is set as m3/h
if(current_unit_F == m3_h)
{

Serial.print("FLOW:");
Serial.print(flowrate_m3_h, 1); //prints value from previous line to serial
Serial.println("M3/H "); //prints label to serial
Serial.print("RATIO:");
Serial.print(Ratio); //prints value from previous line to serial
Serial.println("% "); //prints label to serial
Serial.print("LIVE DP:");
Serial.print(pressureValue12_psi, 1); //prints value from previous line to serial
Serial.println("psi "); //prints label to serial
Serial.print("SP1:");
Serial.println(set_point1_m3_h , 1); //prints value from previous line to serial
Serial.print("SP2:");
Serial.println(set_point2_m3_h, 1); //prints value from previous line to serial


lcd.setCursor(0,0); //sets cursor to column 0, row 0
lcd.print("FLOW   :"); //prints label
lcd.print(flowrate_m3_h, 1); //prints flowrate_psi value to lcd screen, 1 digit on float
lcd.print("M3/H "); //prints label
lcd.print(" "); //prints label


lcd.setCursor(0,1); //sets cursor to column 0, row 1
lcd.print("RATIO  :"); //prints label
lcd.print(Ratio, 1); //prints Ratio value to lcd screen, 1 digit on float
lcd.print("%"); //prints label after value
lcd.print(" "); //to clear the display after large values or negatives




lcd.setCursor(0,2); //sets cursor to column 0, row 2
lcd.print("LIVE DP:"); //prints label
lcd.print(pressureValue12_psi, 1); //prints pressure value to lcd screen, 2 digit on float
lcd.print("psi"); //prints label after value
lcd.print(" "); //to clear the display after large values or negatives

lcd.setCursor(0,3); //sets cursor to column 0, row 3
lcd.print(" SP1:"); //prints label
lcd.print(set_point1_m3_h, 1); //prints pressure value to lcd screen, 2 digit on float
lcd.print(" SP2:"); //prints label after value
lcd.print(set_point2_m3_h , 1);

//turning on relay if condition meet
if(set_point1_m3_h <= flowrate_m3_h)
{
   digitalWrite(relay1 , HIGH);
}
else 
{//turn off relay if condition do not meet
  digitalWrite(relay1 , LOW);
}
//turn on second relay if condition meet
if(set_point2_m3_h <= flowrate_m3_h)
{
   digitalWrite(relay2 , HIGH);
}
else 
{//turn off relay if condition do not meet
  digitalWrite(relay2 , LOW);
}

delay(sensorreadDelay); //delay in milliseconds between read values
}



//run below lines if flow is set as usgpm
else 
{
Serial.print("FLOW:");
Serial.print(flowrate_usgpm, 1); //prints value from previous line to serial
Serial.println("USgpm "); //prints label to serial
Serial.print("RATIO:");
Serial.print(Ratio); //prints value from previous line to serial
Serial.println("% "); //prints label to serial
Serial.print("LIVE DP:");
Serial.print(pressureValue12_bar, 1); //prints value from previous line to serial
Serial.println("psi "); //prints label to serial
Serial.print("SP1:");
Serial.println(set_point1_usgpm, 1); //prints value from previous line to serial
Serial.print("SP2:");
Serial.println(set_point2_usgpm, 1); //prints value from previous line to serial

lcd.setCursor(0,0); //sets cursor to column 0, row 0
lcd.print("FLOW   :"); //prints label
lcd.print(flowrate_usgpm, 1); //prints flowrate_psi value to lcd screen, 1 digit on float
lcd.print("USgpm "); //prints label
lcd.print(" "); //prints label


lcd.setCursor(0,1); //sets cursor to column 0, row 1
lcd.print("RATIO  :"); //prints label
lcd.print(Ratio, 1); //prints Ratio value to lcd screen, 1 digit on float
lcd.print("%"); //prints label after value
lcd.print(" "); //to clear the display after large values or negatives




lcd.setCursor(0,2); //sets cursor to column 0, row 2
lcd.print("LIVE DP:"); //prints label
lcd.print(pressureValue12_bar, 2); //prints pressure value to lcd screen, 2 digit on float
lcd.print("bar"); //prints label after value
lcd.print(" "); //to clear the display after large values or negatives

lcd.setCursor(0,3); //sets cursor to column 0, row 3
lcd.print(" SP1:"); //prints label
lcd.print(set_point1_m3_h , 2); //prints pressure value to lcd screen, 2 digit on float
lcd.print(" SP2:"); //prints label after value
lcd.print(set_point2_m3_h , 2);

//check if relay need to turn on

if(set_point1_usgpm <= flowrate_usgpm )
{
  //turn on relay
   digitalWrite(relay1 , HIGH);
}
else 
{
  //turn off relay if condition do not meet
  digitalWrite(relay1 , LOW);
}
//check if relay need to turn on
if(set_point2_usgpm <= flowrate_usgpm)
{
   digitalWrite(relay2 , HIGH);
}
else 
{//turn off the relay if conditions do not meet
  digitalWrite(relay2 , LOW);
}

delay(sensorreadDelay); //delay in milliseconds between read values
}

//check if menu button pressed
if(digitalRead(menu)==true)
          {
            setting_1 = set_sp1; //set the row selected before settings page load
            lcd.clear();//clear display to remove previous values
            setting_display();//display settings page
            lcd.setCursor(18,0); lcd.print("<");//arrow on first line index 17
            setting_page();//go to settings page to complete settings
            delay(500);

          }

}



//settings page function
void setting_page()
{  
  //setting intial values to load in setting page
   setting_1 = set_sp1;
   set_point1m3_h_temp=set_point1_m3_h;
   set_point2m3_h_temp=set_point2_m3_h;
   set_point1usgpm_temp=set_point1_usgpm;
   set_point2usgpm_temp=set_point2_usgpm;
   temp_unit_F=current_unit_F;
   temp_unit_P=current_unit_P;
   int delay_val = 1000;
  while(1) //stay in this loop until settings complete
  {
    setting_display(); //display setting page
    if (temp_unit_F == m3_h) //if unit is selected as psi run following lines
    {
     switch (setting_1)  //switch case statement to change different settings based on user input
     {
        case set_sp1: // in case menu button is pressed once, update sp1 setting on up and low button
         lcd.setCursor(18,0); lcd.print("<");
          while(digitalRead(up) == HIGH)  // if up button is pressed run following lines
          {
            set_point1m3_h_temp=set_point1m3_h_temp+1;
            set_point1usgpm_temp=set_point1m3_h_temp/4.403;
            setting_display();
            lcd.setCursor(18,0); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;

          while(digitalRead(down) == HIGH) //if down button is pressed run following lines
          {
            set_point1m3_h_temp=set_point1m3_h_temp-1;
            if(set_point1m3_h_temp<0)  set_point1m3_h_temp = 0;
            set_point1usgpm_temp=set_point1m3_h_temp/4.403;
            setting_display();
            lcd.setCursor(18,0); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;
          //run following lines if menu button pressed again
          while(digitalRead(menu)==true)
          {
            setting_1 = set_sp2;//set settings value to sp2
            //runing display page again and assign arrow to next line
            setting_display();
            lcd.setCursor(18,0); lcd.print(" ");
            lcd.setCursor(18,1); lcd.print("<");
            delay(500);
          }
        break;
        case set_sp2: //code to change values for sp2

          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            set_point2m3_h_temp=set_point2m3_h_temp+1;
            set_point2usgpm_temp=set_point2m3_h_temp/4.403;
            setting_display();
            lcd.setCursor(18,1); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;

          while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            set_point2m3_h_temp=set_point2m3_h_temp-1;
            if(set_point2m3_h_temp<0)  set_point2m3_h_temp = 0;
            set_point2usgpm_temp=set_point2m3_h_temp/4.403;
            setting_display();
            lcd.setCursor(18,1); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;

          while(digitalRead(menu)==true)//if menu button pressed again
          {
            setting_1 = set_valve; //apply user action up and down on set_valve
            //load setting page again and show arrow < on next line
            setting_display();
            lcd.setCursor(18,1); lcd.print(" ");
            lcd.setCursor(18,2); lcd.print("<");
            delay(500);
          }

        break;
       case set_valve: // lines to do changes in valve

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            set_valve_temp=valve[0];
            setting_display();
 
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            set_valve_temp=valve[1];
            setting_display();  
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_model;
            setting_display();
            lcd.setCursor(18,2); lcd.print(" ");
            lcd.setCursor(18,3); lcd.print("<");
            delay(500);

          }

        break;
        case set_model: // lines to do changes in unit_P

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            lcd.clear();
            lcd.setCursor(18,2); lcd.print(" ");
            lcd.setCursor(18,3); lcd.print("<");
            if(set_valve_temp==valve[0])
            {
            index_A=index_A-1;
            if(index_A <=0)
              {index_A=37;}
            set_model_temp=model_A[index_A];
            setting_display();
            }  
            else
            {
            index_S=index_S-1;
            if(index_S <=0)
              {index_S=13;}
            set_model_temp=model_S[index_S];
            setting_display();
            }
            
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            lcd.clear();
            lcd.setCursor(18,2); lcd.print(" ");
            lcd.setCursor(18,3); lcd.print("<");
            if(set_valve_temp==valve[0])
            {
            index_A=index_A+1;
            if(index_A >=38)
              {index_A=0;}
            set_model_temp=model_A[index_A];
            setting_display();
            }  
            else
            {
            index_S=index_S+1;
            if(index_S >=14)
              {index_S=0;}
            set_model_temp=model_S[index_S];
            setting_display();
            }
            
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_unit_F;
            setting_display();
            lcd.clear();
            first_screen=false;
            lcd.setCursor(18,3); lcd.print(" ");
            lcd.setCursor(18,0); lcd.print("<");
            //delay(500);
            setting_display();
          }

        break;
        case set_unit_F: // lines to do changes in unit

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {           
            temp_unit_F=m3_h;
            temp_F="M3/H";
            setting_display();           
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            temp_unit_F=usgpm;
            temp_F="USgpm";
            setting_display();
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_unit_P;
            setting_display();
            lcd.setCursor(18,0); lcd.print(" ");
            lcd.setCursor(18,1); lcd.print("<");
            delay(500);
            //lcd.clear();
            first_screen=true;
          }

        break;
       case set_unit_P: // lines to do changes in unit

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            temp_unit_P=psi;
            temp_P="PSI";
            setting_display();
            
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            temp_unit_P=bar;
            temp_P="BAR";
            setting_display();
            
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_sp1;
            setting_display();
            lcd.setCursor(18,1); lcd.print(" ");
            lcd.setCursor(18,0); lcd.print("<");
            delay(500);
          }

        break;

     }
   }

 else //if pressure is selected as bar
  {
     ////**************** same format as settings in psi *****************//////
    /// just displying different pressure on screen
 switch (setting_1) {
        case set_sp1:
        lcd.setCursor(18,0); lcd.print("<");
          while(digitalRead(up) == HIGH) 
          {
            set_point1bar_temp = set_point1bar_temp +1;
            set_point1psi_temp = set_point1bar_temp* 0.0689476;
            setting_display();
            lcd.setCursor(17,0); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;

          while(digitalRead(down) == HIGH) 
          {
            set_point1bar_temp = set_point1bar_temp -1;
            if(set_point1bar_temp<0)  set_point1bar_temp = 0;
            set_point1psi_temp = set_point1bar_temp* 0.0689476;
            setting_display();
            lcd.setCursor(18,0); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;

          while(digitalRead(menu)==true)
          {
            setting_1 = set_sp2;
            setting_display();
            lcd.setCursor(18,0); lcd.print(" ");
            lcd.setCursor(18,1); lcd.print("<");
            delay(500);
          }
        break;
        case set_sp2:

          while(digitalRead(up) == HIGH) 
          {
            set_point2bar_temp = set_point2bar_temp +1;
            set_point2psi_temp = set_point2bar_temp* 0.0689476;
            setting_display();
            lcd.setCursor(18,1); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;

          while(digitalRead(down) == HIGH) 
          {
            set_point2bar_temp = set_point2bar_temp -1;
            if(set_point2bar_temp<0) set_point2bar_temp = 0;
            set_point2psi_temp = set_point2bar_temp* 0.0689476;
            setting_display();
            lcd.setCursor(18,1); lcd.print("<");
            delay(delay_val);
            delay_val = delay_val - 100;
            if(delay_val ==0) delay_val = 100;
          }
          delay_val = 1000;

          while(digitalRead(menu)==true)
          {
            setting_1 = set_valve;
            setting_display();
            lcd.setCursor(18,1); lcd.print(" ");
            lcd.setCursor(18,2); lcd.print("<");
            delay(500);
          }

        break;
        case set_valve:

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            
            set_valve_temp=valve[0];
            setting_display();
            
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            set_valve_temp=valve[1];
            setting_display();
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_model;
            setting_display();
            lcd.setCursor(18,2); lcd.print(" ");
            lcd.setCursor(18,3); lcd.print("<");
            delay(500);

          }

        break;
        case set_model: // lines to do changes in unit_P

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            lcd.clear();
            lcd.setCursor(18,2); lcd.print(" ");
            lcd.setCursor(18,3); lcd.print("<");
            if(set_valve_temp==valve[0])
            {
            index_A=index_A-1;
            if(index_A <=0)
              {index_A=37;}
            set_model_temp=model_A[index_A];
            setting_display();
            }  
            else
            {
            index_S=index_S-1;
            if(index_S <=0)
              {index_S=13;}
            set_model_temp=model_S[index_S];
            setting_display();
            }
            
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            lcd.clear();
            lcd.setCursor(18,2); lcd.print(" ");
            lcd.setCursor(18,3); lcd.print("<");
            if(set_valve_temp==valve[0])
            {
            index_A=index_A+1;
            if(index_A >=38)
              {index_A=0;}
            set_model_temp=model_A[index_A];
            setting_display();
            }  
            else
            {
            index_S=index_S+1;
            if(index_S >=14)
              {index_S=0;}
            set_model_temp=model_S[index_S];
            setting_display();
            }
            
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_unit_F;
            setting_display();
            lcd.clear();
            first_screen=false;
            lcd.setCursor(18,3); lcd.print(" ");
            lcd.setCursor(18,0); lcd.print("<");
            //delay(500);
            setting_display();
          }

        break;
        case set_unit_F: // lines to do changes in unit

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            temp_unit_F=m3_h;
            temp_F="M3/H";
            setting_display();   
            
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            temp_unit_F=usgpm;
            temp_F="USgpm";
            setting_display();   
            
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_unit_P;
            setting_display();
            lcd.setCursor(18,0); lcd.print(" ");
            lcd.setCursor(18,1); lcd.print("<");
            delay(500);
            //lcd.clear();
            first_screen=true;
          }

        break;
       case set_unit_P: // lines to do changes in unit

        while(digitalRead(down) == HIGH) //if down button pressed run following lines
          {
            temp_unit_P=psi;
            temp_P="PSI";
            setting_display();   
            
          }
          while(digitalRead(up) == HIGH) //if up button pressed run following lines
          {
            temp_unit_P=bar;
            temp_P="BAR";
            setting_display();   
            
          }


        while(digitalRead(menu)==true)//if menu button pressed move arrow to next position
          {
            setting_1 = set_sp1;
            setting_display();
            lcd.setCursor(18,1); lcd.print(" ");
            lcd.setCursor(18,0); lcd.print("<");
            delay(500);
          }

        break;
          }
  }

if(digitalRead(set)==true) // if set button pressed exit from the while loop
          {
            lcd.clear();
            setting_1 = set_sp1;
            save_display();
            delay(1000);
            break;
          }

}

save_page();//load save page

}


void pressure_measurement()
//function to read pressure values
{
pressureValue1_psi = analogRead(pressureInput1); //reads value from input pin and assigns to variable
pressureValue2_psi = analogRead(pressureInput2);
pressureValue1_psi = ((pressureValue1_psi-pressureZero)*pressuretransducermaxPSI)/(pressureMax-pressureZero); //conversion equation to convert analog reading to psi
pressureValue2_psi = ((pressureValue2_psi-pressureZero)*pressuretransducermaxPSI)/(pressureMax-pressureZero); //conversion equation to convert analog reading to psi
if(pressureValue1_psi< 0) pressureValue1_psi = 0;
if(pressureValue2_psi< 0) pressureValue2_psi = 0;
pressureValue12_psi = pressureValue1_psi - pressureValue2_psi;
// if(pressureValue12_psi < 0) pressureValue12_psi = pressureValue12_psi*-1;
//bar to psi conversion
pressureValue1_bar  = pressureValue1_psi/14.5038;
pressureValue2_bar  = pressureValue2_psi/14.5038;
pressureValue12_bar = pressureValue12_psi/14.5038;

}


void setting_display()
{
 if(temp_unit_F == m3_h)
{
if(((setting_1 == set_sp1)&&(first_screen==true))||(setting_1 == set_sp2)||(setting_1 == set_valve)||(setting_1 == set_model))
{
lcd.setCursor(0,0); //sets cursor to column 0, row 0
lcd.print("SET SP1:"); //prints label
lcd.print(set_point1m3_h_temp,1); //prints pressure value to lcd screen, 1 digit on float
lcd.print("M3/H"); //prints label
lcd.print(" "); //prints label


lcd.setCursor(0,1); //sets cursor to column 0, row 01
lcd.print("SET SP2:"); //prints label
lcd.print(set_point2m3_h_temp,1); //prints pressure value to lcd screen, 1 digit on float
lcd.print("M3/H"); //prints label after value
lcd.print(" "); //to clear the display after large values or negatives




lcd.setCursor(0,2); //sets cursor to column 0, row 02
lcd.print("VALVE  :"); //prints label
lcd.print(set_valve_temp); //prints pressure value to lcd screen, 1 digit on float
//lcd.print(" "); //prints label after value

lcd.setCursor(0,3); //sets cursor to column 0, row 03
lcd.print("MODEL  :"); //prints label
lcd.print(set_model_temp); //prints label after value
//lcd.print(" "); //prints label after value
}

if((setting_1 == set_unit_F)||(setting_1 == set_unit_P))
{
lcd.setCursor(0,0); //sets cursor to column 0, row 03
lcd.print("UNIT(F):"); //prints label
lcd.print(temp_F); //prints label after value

lcd.setCursor(0,1); //sets cursor to column 0, row 03
lcd.print("UNIT(P):"); //prints label
lcd.print(temp_P); //prints label after value
}

}
else 
{
lcd.setCursor(0,0); //sets cursor to column 0, row 0
lcd.print("SET SP1:"); //prints label
lcd.print(set_point1usgpm_temp, 2); //prints pressure value to lcd screen, 1 digit on float
lcd.print("USgpm"); //prints label
lcd.print(" "); //prints label


lcd.setCursor(0,1); //sets cursor to column 0, row 1
lcd.print("SET SP2:"); //prints label
lcd.print(set_point2usgpm_temp, 2); //prints pressure value to lcd screen, 1 digit on float
lcd.print("USgpm"); //prints label after value
lcd.print(" "); //to clear the display after large values or negatives




lcd.setCursor(0,2); //sets cursor to column 0, row 2
lcd.print("VALVE  :"); //prints label
lcd.print(set_valve_temp); //prints pressure value to lcd screen, 1 digit on float
lcd.print(" "); //to clear the display after large values or negatives

lcd.setCursor(0,3); //sets cursor to column 0, row 03
lcd.print("MODEL  :"); //prints label
lcd.print(set_model_temp); //prints label after value

if((setting_1 == set_unit_F)||(setting_1 = set_unit_P))
{
lcd.setCursor(0,0); //sets cursor to column 0, row 03
lcd.print("UNIT(F):"); //prints label
lcd.print(temp_F); //prints label after value

lcd.setCursor(0,1); //sets cursor to column 0, row 03
lcd.print("UNIT(P):"); //prints label
lcd.print(temp_P); //prints label after value
}
} 
}

void save_display()
{
  lcd.setCursor(0,0); //sets cursor to column 0, row 0
  lcd.print("SAVE THE VALUES?"); //prints label
  lcd.setCursor(0,2); //sets cursor to column 0, row 02
  lcd.print("PRESS SET TO SAVE"); //prints label
  lcd.setCursor(0,3); //sets cursor to column 0, row 03
  lcd.print("PRESS MENU TO CANCEL"); //prints label
  
}
void save_page()
{
  while(1)
  {
  if(digitalRead(set) == HIGH) //read the button by user to save or discard settings
  {
   set_point1_usgpm = set_point1psi_temp;
   set_point2_usgpm = set_point2psi_temp;
   set_point1_m3_h = set_point1bar_temp;
   set_point2_m3_h = set_point2bar_temp;
   current_unit_F = temp_unit_F;
   current_unit_P = temp_unit_P;
   lcd.clear();
   return;
  }
  if (digitalRead(menu) == HIGH)
  {
    lcd.clear();
    return;
  }
  }
}