Arduino Photoresistor LED On/off

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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! ;)

2 People Made This Project!

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6 Discussions

0
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jagganath

8 months ago

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

0
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RăzvanN4

1 year ago

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

0
None
HarDizzeR

1 year ago

Can I use 12v led strips ?

0
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Lionbait

3 years ago

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.

1 reply
0
None
PaigeK8Lionbait

Reply 3 years ago

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); }

}

0
None
PaigeK8

3 years ago

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); }

}