Arduino Powered Emission Control System

#include <OneWire.h>
#include <DS18B20.h>
#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BMP085_U.h>

const byte ONEWIRE_PIN = 2;
byte sensorAddress1[8] = {0x28, 0xFF, 0x35, 0x26, 0x86, 0x16, 0x4, 0xF3};
byte sensorAddress2[8] = {0x28, 0xFF, 0x67, 0x20, 0x86, 0x16, 0x4, 0xEC};
int g1,g2,g3,t1,t2,conv,perc;
float p1,p2;
OneWire onewire(ONEWIRE_PIN);
DS18B20 sensors(&onewire);
Adafruit_BMP085_Unified bmp = Adafruit_BMP085_Unified(10085);

int thValue = 200;

void setup() {
  sensors.begin();
  Serial.begin(9600);
  Serial1.begin(9600);
  Serial2.begin(9600);
  pinMode(22, OUTPUT);
  pinMode(24, OUTPUT);
  bmp.begin();

}

void loop() {
  tempRead();
  readGas();
  displaySensorDetails();
  readProMini();
  printSerial();
  lcdDisplay();
}


void tempRead() {
  sensors.request(sensorAddress1);
  t1 = sensors.readTemperature(sensorAddress1);
  while (!sensors.available());
  sensors.request(sensorAddress2);
  t2 = sensors.readTemperature(sensorAddress2);
}

void readGas(){
  g1 = analogRead(A0);
  g2 = analogRead(A1) + 60;
  g3 = analogRead(A2) + 75;
  if(g1>g2){
    conv=1;
    perc=(g3-g1)*100/g3;
  }else{
    conv=2;
    perc=(g3-g2)*100/g3;
  }
  
  if (g3 > thValue)
  {
    digitalWrite(24, HIGH);
    delay(1000);
    digitalWrite(24, LOW);
    delay(1000);
    alarm();
  }
  else {
    digitalWrite(22, HIGH);
    digitalWrite(24, HIGH);
  }
}

void displaySensorDetails(){
  sensors_event_t event;
  bmp.getEvent(&event);
  if (event.pressure)
  {
    p1=event.pressure;
    p1=p1/1000;
  }
  else
  {
    Serial.println("Sensor error");
  }
  delay(1000);
}

void readProMini(){
  Serial1.flush();
  while(!Serial1.available()){
  }
  Serial1.read();
    String text =  Serial1.readStringUntil(13);
    
    if(text.startsWith("P")){
      text = text.substring(1);
      float x = text.toInt();
      if(x>900){
        p2=x/1000;
      }      
    }
}

void printSerial(){
  Serial.print(g1);
  Serial.print("  ");
  Serial.print(g2);
  Serial.print("  ");
  Serial.print(g3);
  Serial.print("  ");
  Serial.print(t1);
  Serial.print("  ");
  Serial.print(t2);
  Serial.print("  ");
  Serial.print(p1);
  Serial.print("  ");
  Serial.print(p2);
  Serial.println("  ");
}

void lcdDisplay(){
  printData("t0",t2);
  printDataFloat("t1",p1);
  printData("t2",t1);
  printDataFloat("t3",p2);
  printData("t4",conv);
  printData("t5",perc);
}

void printData(String id, int val){
  Serial2.print(id);
  Serial2.print(".txt=");
  Serial2.write(0x22);
  Serial2.print(val);
  if(id=="t5"){
    Serial2.print("%");
  }
  Serial2.write(0x22);
  Serial2.write(0xff);
  Serial2.write(0xff);
  Serial2.write(0xff);
  delay(100);
}

void printDataFloat(String id, float val){
  Serial2.print(id);
  Serial2.print(".txt=");
  Serial2.write(0x22);
  Serial2.print(val,2);
  Serial2.write(0x22);
  Serial2.write(0xff);
  Serial2.write(0xff);
  Serial2.write(0xff);
  delay(100);
}

void alarm(){
  tone(48,800);
  delay(500);
  tone(48,1500);
  delay(500);
  noTone(48);
}