Project 1

1.Switching ON/OFF Lights based on light intensity:

Hardware Required

• NodeMCU
• LDR
• Resistor
• LED
• Breadboard
• Micro USB cable
• Connecting Wires

LDR : Output is analog in nature, so it gets connected to the A0 pin of the NodeMCU.

LED : It is connected to D1 pin and to Ground(GND) pin of NodeMCU.

Program:

const int ledPin = 5; //Pin no 5 to led
const int ldrPin = A0;//ldr pin to analog pin

void setup()

{

Serial.begin(9600);//start the serial transmission

pinMode(ledPin, OUTPUT);//setting the ledpin to output mode

pinMode(ldrPin, INPUT);//setting ldr pin to input mode

}

void loop() {

int ldrStatus = analogRead(ldrPin);//reading the ldr value and storing it in a variable

if (ldrStatus <=300)//checking the condition if it is less than the threshold(300)

{

digitalWrite(ledPin, HIGH);//turning on the light

Serial.print(ldrStatus);//printing the value of ldr on serial monitor

Serial.println("It is DARK, LED is ON");//print a message

}

else//if condition is not satisfied

{

digitalWrite(ledPin, LOW);//turn off the light

Serial.println("LED is OFF");//print a message

}

}

2.Switching ON/OFF fan based on temperature:

Hardware Required

• NodeMCU
• Fan
• Resistor
• DHT11 sensor
• Breadboard
• Micro USB cable
• Connecting Wires

int redLed = 10;//components are assigned to  the pins red led to pin 10,green to pin 12,buzzer to 8 and smoke sensor to A0
int greenLed = 12;
int buzzer = 8;
int smokeA0 = A0;
// Your threshold value
int sensorThres = 100;

void setup()
 {
  pinMode(redLed, OUTPUT);//setting pin modes
  pinMode(buzzer, OUTPUT);//redled and green led as output
  pinMode(smokeA0, INPUT);//smoke sensor as input
  Serial.begin(9600);//serial data transmission starts at baud rate of 9600
  }

void loop() {
  int analogSensor = analogRead(smokeA0);//read the smoke sensor value
  // Checks if it has reached the threshold value
  if (analogSensor > sensorThres)
  {
    digitalWrite(redLed, HIGH); //if yes then turn the red light and turn on the buzzer  
    digitalWrite(12, LOW);
    tone(buzzer, 1000, 200);
  }
  else
  {
    digitalWrite(redLed, LOW);//if no then turn on the green light and turn off the buzzer
    digitalWrite(12, HIGH);    
     noTone(buzzer);
  }
  delay(500);
}