Example 1.2

// Example 1.2

int red = 11; // the pins for the LED
int green = 9;
int blue = 10;
int i = 0; // for loops
int j = 0;

void setup()
{
	pinMode(red, OUTPUT); // tell Arduino LED is an output
	pinMode(green, OUTPUT);
	pinMode(blue, OUTPUT);
}

void loop()
{
	// first, cycle up each primary colour twice
	for (j = 1; j < 6; j++)
	{  // loop 5 times
		for (i = 0; i < 255; i++)
		{ // loop from 0 to 254 (fade in)
			analogWrite(red, i);      // set the LED brightness
			delay(20); // Wait 10ms because analogWrite isn't instant
		}
		analogWrite(red,0);
		delay (20);
		for (i = 0; i < 255; i++)
		{ // loop from 0 to 254 (fade in)
			analogWrite(green, i);      // set the LED brightness
			delay(20); // Wait 10ms because analogWrite isn't instant
		}
		delay (20);
		analogWrite(green,0);
		for (i = 0; i < 255; i++)
		{ // loop from 0 to 254 (fade in)
			analogWrite(blue, i);      // set the LED brightness
			delay(20); // Wait 10ms because analogWrite isn't instant
		}
		delay (20);
		analogWrite(blue,0);
	}
	// psychadelic time
	for (j = 1; j < 10000; j++)
	{
		analogWrite(red,random(255)); // set red at random brightness between 0 and 254
		delay (random(10,31));           // wait for a random duration between 10 and 30 milliseconds
		analogWrite(green,random(255));
		delay (random(10,31));
		analogWrite(blue,random(255));
		delay (random(10,31));
	}
}