i spent a little time last night playing with arduino and i thought i’d share this little experiment i put together.
Arduino + Photo Resistor + LED from Joshua McGinnis on Vimeo.
here’s the source:
/*
* Power LED on Dark by Joshua McGinnis
*
* This basic example uses a photo resistor to determine
* whether light is present or not. If it is not, an led
* will be set to high.
*
* http://www.joshuamcginnis.com
*/
int photoPin = 1; // designate pin 1 as the analog in for the photo resitor
int val = 0;
int ledPin = 13; // designate pin 1 as the analog in for the photo resitor
void setup() // run once, when the sketch starts
{
Serial.begin(9600);
pinMode(ledPin,OUTPUT); // set the pin
pinMode(photoPin,OUTPUT); // set the pin
}
void loop() // run over and over again
{
val = analogRead(photoPin); // set val equal to the resitor input
if(val == LOW) { // if nothing from photo resistor (low light), turn on led
digitalWrite(ledPin, HIGH);
delay(500);
} else {
digitalWrite(ledPin, LOW);
}
Serial.println(val);
}
* Power LED on Dark by Joshua McGinnis
*
* This basic example uses a photo resistor to determine
* whether light is present or not. If it is not, an led
* will be set to high.
*
* http://www.joshuamcginnis.com
*/
int photoPin = 1; // designate pin 1 as the analog in for the photo resitor
int val = 0;
int ledPin = 13; // designate pin 1 as the analog in for the photo resitor
void setup() // run once, when the sketch starts
{
Serial.begin(9600);
pinMode(ledPin,OUTPUT); // set the pin
pinMode(photoPin,OUTPUT); // set the pin
}
void loop() // run over and over again
{
val = analogRead(photoPin); // set val equal to the resitor input
if(val == LOW) { // if nothing from photo resistor (low light), turn on led
digitalWrite(ledPin, HIGH);
delay(500);
} else {
digitalWrite(ledPin, LOW);
}
Serial.println(val);
}
ril3y
February 13, 2009 at 10:30 pmVery cool stuff man… I just got my arduino trying to see all the different things people are doing with them..
-ril3y
http://www.synthetos.com
alwolf
March 3, 2009 at 6:01 pmHello, I copied and pasted your code above into the IDE and recieve this error:
In function ‘void setup()’:
error: ‘ledPin2’ was not declared in this scope
Do we need to initialize an “ledpin2” like you did for ledPin?
John
May 27, 2009 at 6:24 pmpinMode(ledPin2,OUTPUT); // set the pin
should be
pinMode(photoPin,OUTPUT); // set the pin
Joshua
June 2, 2009 at 10:50 amthanks!
ricky
June 19, 2010 at 3:28 pmIts called a protoSheild not a borduino….but a borduino may be another name……
Andy
December 5, 2010 at 6:15 amyou really should have a current limiting resistor on your LED — (see how bright it gets in your demo video). Try something in the range of 330ohms or so to prevent damage to your board. that, or use pwm.