Arduino Photoresistor LED On/off

this is another simple arduino project that turn on light when it's dark and turn off when is light))

Step 1: Materials

You will need:

Arduino

Breadboard

2x 240ohm resistors

1x Clear White l.e.d

1x photoresistor

Some Jumper Cables

Step 2: Circuite

Step 3: The Code

//photoresistor A Style Tech.

int Pr = 0; // will be used for analog 0.

int PrValue = 0; // value of output

int Pr_Input = 19; // value of when light is on

void setup() {

Serial.begin(9600); //start serial Monitor

pinMode(8, OUTPUT); // pin 8 as output

}

void loop() {

PrValue = analogRead(Pr);

Serial.println(PrValue); //prints photoresistor value

delay(100); // value updated every 0.1 second.

if (PrValue < Pr_Input) // if sensor value is less than 19, light will turn on.

{ digitalWrite(8, HIGH);//LED on } else { digitalWrite(8, LOW);// LED off }

}

Step 4: Finish!!

if all went well, try to add more leds

and change sensitivity of photoresistor " int Pr_Input = 19; // value of when light is on"

GOOD LUCK! ;)

Comments

[macca6]

As with most of the other "instructables", it's not informative and can be dangerous. No information provided on photoresistor type, LED type and other attributes, no pin diagram or markings, and as expected, the code doesn't compile. Please don't write any more of these.

[jagganath]

there are several TYPES of photoresistor, from GL5506 to GL5539. Which one did you use? and which one is the best?

[RăzvanN4]

Can i make the same project (photoresistor-LED-on/off) combined with a speedometer, using the same arduino board and the same breadboard?

[HarDizzeR]

Can I use 12v led strips ?

[Lionbait]

Any one else getting this message, when trying to load the code

Arduino: 1.6.5 (Windows 8.1), Board: "Arduino Uno"

sketch_feb23a.ino: In function 'void loop()':
sketch_feb23a:37: error: expected '}' at end of input
expected '}' at end of input

This report would have more information with
"Show verbose output during compilation"
enabled in File > Preferences.

[PaigeK8]

int Pr = 0; // will be used for analog 0.

int PrValue = 0; // value of output

int Pr_Input = 19; // value of when light is on

void setup() {

Serial.begin(9600); //start serial Monitor

pinMode(8, OUTPUT); // pin 8 as output

}

void loop() {

PrValue = analogRead(Pr);

Serial.println(PrValue); //prints photoresistor value

delay(100); // value updated every 0.1 second.

if (PrValue < Pr_Input) {

digitalWrite(8, HIGH);

} else {

digitalWrite(8, LOW); }

}

[PaigeK8]

USE THIS

int Pr = 0; // will be used for analog 0.

int PrValue = 0; // value of output

int Pr_Input = 19; // value of when light is on

void setup() {

Serial.begin(9600); //start serial Monitor

pinMode(8, OUTPUT); // pin 8 as output

}

void loop() {

PrValue = analogRead(Pr);

Serial.println(PrValue); //prints photoresistor value

delay(100); // value updated every 0.1 second.

if (PrValue < Pr_Input) {

digitalWrite(8, HIGH);

} else {

digitalWrite(8, LOW); }

}