Overview
This project tells about how to use a photoresistor sensor to glow an LED this is very useful to detect light.
In this project when there is light present Led will be Off and in night Led will automatically turns On.
Hardware required
- Arduino Uno R3
- LED
- Resistor
- Jumper Wires
- Photoresistor Sensor
Schematic Diagram
Fig 1. Circuit Diagram
Arduino Code :
int light = 0; // store the current light value
void setup() {
// put your setup code here, to run once:
Serial.begin(9600); //configure serial to talk to computer
pinMode(7, OUTPUT); // configure digital pin 7 as an output
}
void loop() {
// put your main code here, to run repeatedly:
light = analogRead(A0); // read and save value from PR
Serial.println(light); // print current light value
if(light > 450) { // If it is bright...
Serial.println("It is quite light!");
digitalWrite(7,LOW); //turn LED off
}
else if(light > 229 && light < 451) { // If it is average light...
Serial.println("It is average light!");
digitalWrite(7, HIGH); // turn LED on
}
else { // If it's dark...
Serial.println("It is pretty dark!");
digitalWrite(7,HIGH); // Turn LED on
}
delay(1000); // don't spam the computer!
}
Precautions
- Connections should be done properly.
- Arduino is case Sensitive so code accordingly.
- Give different and appropriate colors to the wires.
- Use resistors for sensors and LED’s.