why i kept wrong putting my code for air pollution detection anything false? this is my code
#include "LCD.h"
#include "LiquidCrystal_I2C.h"
LiquidCrystal_I2C::LiquidCrystal_I2C(0x27,2,1,0,4,5,6,7);
#include "MQ135.h"
#define ANALOGPIN A2 // Define Analog PIN on Arduino Board
#define RZERO 206.85 // Define RZERO Calibration Value
MQ135 gasSensor = MQ135(ANALOGPIN);
int buz = 8; //buzzer connected to pin 8
int led = 9; //led connected to pin 9
const int aqsensor = A0; //output of mq135 connected to A0 pin of Arduino
int threshold = 250; //Threshold level for Air Quality
void setup() {
pinMode (buz,OUTPUT); // buzzer is connected as Output from Arduino
pinMode (led,OUTPUT); // led is connected as output from Arduino
pinMode (aqsensor,INPUT); // MQ135 is connected as INPUT to arduino
Serial.begin (9600); //begin serial communication with baud rate of 9600
lcd.clear(); // clear lcd
lcd.begin (16,2); // consider 16,2 lcd
}
void loop() {
int ppm = analogRead(aqsensor); //read MQ135 analog outputs at A0 and store it in ppm
Serial.print("Air Quality: "); //print message in serail monitor
Serial.println(ppm); //print value of ppm in serial monitor
lcd.setCursor(0,0); // set cursor of lcd to 1st row and 1st column
lcd.print("Air Qualit: "); // print message on lcd
lcd.print(ppm); // print value of MQ135
if (ppm > threshold) // check is ppm is greater than threshold or not
{
lcd.setCursor(1,1); //jump here if ppm is greater than threshold
lcd.print("AQ Level HIGH");
Serial.println("AQ Level HIGH");
tone(led,1000,200); //blink led with turn on time 1000mS, turn off time 200mS
digitalWrite(buz,HIGH); //Turn ON Buzzer
}
else
{
digitalWrite(led,LOW); //jump here if ppm is not greater than threshold and turn off LED
digitalWrite(buz,LOW); //Turn off Buzzer
lcd.setCursor(1,1);
lcd.print ("AQ Level Good");
Serial.println("AQ Level Good");
}
delay (500);
}
