Multiple LEDs Fading

Other Hardware LEDs and Multiplexing
1

Hi everybody,

I want to do fade in and fade out for 2 leds (then more leds). I do that but with it's very long codes. I'm sure there must be a short codes but i can't find it. Could you help me about it?

I attached my long codes. So you can understand what i want with this code.

Thanks a lot.

_2_led_fading.ino (29.6 KB)

2

Is it going linear up and down ? Not even a nice sine wave or a visual eye-sensitivity curve ?

int i;

for( i=0; i<=255; i++)
{
  analogWrite( p1, i);
  analogWrite( p2, 255-i);
  delay( 2);
}

for( i=0; i<=255; i++)
{
  analogWrite( p1, 255-i);
  analogWrite( p2, i);
  delay( 2);
}
3

Thank you so much, this is what i want :wink:

My last code is here, maybe anyone need code like this;

int p1 = 3;
int p2 = 5;
int p3 = 6;
int p4 = 9;
int p5 = 10;
int p6 = 11;

void setup() {
  pinMode(p1, OUTPUT);
  pinMode(p2, OUTPUT);
  pinMode(p3, OUTPUT);
  pinMode(p4, OUTPUT);
  pinMode(p5, OUTPUT);
  pinMode(p6, OUTPUT);
}

void loop() {
int i;
//

for( i=0; i<=255; i+=2)
{
  analogWrite( p2, i);
  analogWrite( p1, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p3, i);
  analogWrite( p2, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p4, i);
  analogWrite( p3, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p5, i);
  analogWrite( p4, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p6, i);
  analogWrite( p5, 255-i);
  delay( 2);
}
//
for( i=0; i<=255; i+=2)
{
  analogWrite( p5, i);
  analogWrite( p6, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p4, i);
  analogWrite( p5, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p3, i);
  analogWrite( p4, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p2, i);
  analogWrite( p3, 255-i);
  delay( 2);
}

for( i=0; i<=255; i+=2)
{
  analogWrite( p1, i);
  analogWrite( p2, 255-i);
  delay( 2);
}
}
4

Why on earth would you do it like that? It's a massive amount of code that's just copy past. A rule of thumb, if your code is a bunch of copy past than there is a better way! And I hope you don't need the Arduino for something else?

Here an edit that frees up the Arduino (it doesn't use delay) and is scaleble.

const byte LedPins[] = {3, 5, 6, 9, 10, 11};
const unsigned int FadeInterval = 20;
const unsigned int FadeStepsize = 20;

#define NLEDS (sizeof(LedPins)/sizeof(LedPins[0]))


void setup() {
	for(byte i = 0; i < (sizeof(LedPins) / sizeof(LedPins[0])); i++){
		pinMode(LedPins[i], OUTPUT);
	}
}

void loop() {
	fadeLoop();
}

void fadeLoop(){
	static unsigned long lastMillis;
	
	//only alter the fading once every FadeInterval
	if(millis() - lastMillis > FadeInterval){
		lastMillis = millis();
		fadeDo();
	}
}

void fadeDo(){
	static byte i;
	static bool dir;
	static byte brightness;
	
	//last brightness was max, time to go to the next
	if(brightness == 255){
		brightness = FadeStepsize;
		i++;
	}
	//if FadeStepsize would overshoot
	else if(255 - brightness < FadeStepsize){
		brightness = 255;
	}
	//just increase the brightness
	else{
		brightness += FadeStepsize;
	}
	
	if(i == ( sizeof(LedPins) / sizeof(LedPins[0]) ){
		i = 0;
		dir != dir;
	}
	
	//do the fading
	if(dir){
		analogWrite(LedPins[i], 255 - brightness);
		analogWrite(LedPins[i + 1], brightness);
	}
	else{
		analogWrite(LedPins[NLEDS - i, 255 - brightness);
		analogWrite(LedPins[NLEDS - i - 1, brightness);
	}
}
5

Yes, this is better.

Normally i don't need Arduino but i just use Arduino for test.

Thanks a lot.