Components

potentiometer x 2

red, green and blue LEDs

wires

arduino board and bread board

Brightness of a single LED (with one pot)

In the first part, we control the brightness of the green LED with one potentiometer.

Code

/*
 * one pot fades one led
 * modified version of AnalogInput
 * by DojoDave <http://www.0j0.org>
 * http://www.arduino.cc/en/Tutorial/AnalogInput
 */
int potPin = 0;   // select the input pin for the potentiometer
int ledPin = 10;   // select the pin for the LED
int val = 0;      // variable to store the value coming from the sensor
void setup() {
  Serial.begin(9600);
}
void loop() {
  val = analogRead(potPin);    // read the value from the sensor, between 0 - 1024
  Serial.println(val);
  analogWrite(ledPin, val/4); // analogWrite can be between 0-255
}

Demo

The following two pictures show the different brightness of the green LED controlled by a poteniometer.

Blinking of a single LED (with one pot)

In this part, we control the blinking rate of the green LED with one potentiometer.

Code

/*
 * AnalogInput
 * by DojoDave <http://www.0j0.org>
 *
 * Turns on and off a light emitting diode(LED) connected to digital 
 * pin 13. The amount of time the LED will be on and off depends on
 * the value obtained by analogRead(). In the easiest case we connect
 * a potentiometer to analog pin 2.
 *
 * http://www.arduino.cc/en/Tutorial/AnalogInput
 */
int potPin = 0;    // select the input pin for the potentiometer
int ledPin = 10;   // select the pin for the LED
int val = 0;       // variable to store the value coming from the sensor
void setup() {
  pinMode(ledPin, OUTPUT);  // declare the ledPin as an OUTPUT
}
void loop() {
  val = analogRead(potPin);    // read the value from the sensor
  digitalWrite(ledPin, HIGH);  // turn the ledPin on
  delay(val);                  // stop the program for some time
  digitalWrite(ledPin, LOW);   // turn the ledPin off
  delay(val);                  // stop the program for some time
}

Demo

The following two videos show the different blinking rates controlled by a potentiometer.

video 1, video 2

Blinking and lightness of a single LED (with two pots)

Code

/*
 * one pot dims, the other pot changes the blinking rate
 * modification of the following
 * http://www.arduino.cc/en/Tutorial/AnalogInput
 */
int pot1Pin = 0;   // select the input pin for the potentiometer 1
int pot2Pin = 1;   // select the input pin for the potentiometer 2
int pot1Val = 0;   // variable to store the value coming from pot 1
int pot2Val = 0;   // variable to store the value coming from pot 2
int led1Pin = 10;   // select the pin for the LED 1
int led2Pin = 11;  // select the pin for the LED 2
void setup() {
   pinMode(led1Pin, OUTPUT);  // declare the led1Pin as an OUTPUT
   pinMode(led2Pin, OUTPUT);  // declare the led2Pin as an OUTPUT
}
void loop() {
   pot1Val = analogRead(pot1Pin);   // read the value from pot 1, between 0 - 1024, for dimming
   pot2Val = analogRead(pot2Pin);   // read the value from pot 2, between 0 - 1024, for blinking
   analogWrite(led1Pin, pot1Val/4); // dim LED to value from pot1
   delay(pot2Val);                  // stop the program for some time, meaning, LED is on for this time
   analogWrite(led1Pin, 0);         // dim LED to completely dark (zero)
   delay(pot2Val);                  // stop the program for some time, meaning, LED is OFF for this time
}

Three LEDs blinking in alternately(with two pots)

Code

/*
 * one pot dims, the other pot changes the blinking rate
 * modification of the following
 * http://www.arduino.cc/en/Tutorial/AnalogInput
 */
int pot1Pin = 0;   // select the input pin for the potentiometer 1
int pot2Pin = 1;   // select the input pin for the potentiometer 2
int pot1Val = 0;   // variable to store the value coming from pot 1
int pot2Val = 0;   // variable to store the value coming from pot 2
int led1Pin = 9;   // select the pin for the LED 1
int led2Pin = 10;  // select the pin for the LED 2
int led3Pin = 11;  // select the pin for the LED 3
void setup() {
   pinMode(led1Pin, OUTPUT);  // declare the led1Pin as an OUTPUT
   pinMode(led2Pin, OUTPUT);  // declare the led2Pin as an OUTPUT
}
void loop() {
   pot1Val = analogRead(pot1Pin);   // read the value from pot 1, between 0 - 1024, for dimming
   pot2Val = analogRead(pot2Pin);   // read the value from pot 2, between 0 - 1024, for blinking
   analogWrite(led1Pin, pot1Val/4); // dim LED to value from pot1
   delay(pot2Val);                  // stop the program for some time, meaning, LED is on for this time
   analogWrite(led1Pin, 0);         // dim LED to completely dark (zero)
   delay(pot2Val);                  // stop the program for some time, meaning, LED is OFF for this time
   analogWrite(led2Pin, pot1Val/4); // dim LED to value from pot1
   delay(pot2Val);                  // stop the program for some time, meaning, LED is on for this time
   analogWrite(led2Pin, 0);         // dim LED to completely dark (zero)
   delay(pot2Val);                  // stop the program for some time, meaning, LED is OFF for this time
   analogWrite(led3Pin, pot1Val/4); // dim LED to value from pot1
   delay(pot2Val);                  // stop the program for some time, meaning, LED is on for this time
   analogWrite(led3Pin, 0);         // dim LED to completely dark (zero)
   delay(pot2Val);                  // stop the program for some time, meaning, LED is OFF for this time
  
}