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## Walking/Marquee effect for LED Strip

I'm trying to achieve a "walking-type" effect also called marquee-effect using individually wired LEDs, so that it seems the lights are moving from one end to the other. Here's a video for reference:
https://www.youtube.com/watch?v=p4g2NFQps1g

It is easy enough if we have repetition every 3 LEDs. But my restriction is that I have repetition every 2 LEDs. The circuit is something like the one in the diagram(pardon my MS Paint skills):

Every other RGB LED is connected together.  One simple way to provide the effect is to show color1 in LEDs at odd position and color2 in LEDs at even positions and then switch them. This is different from a similar effect in cheap fairy lights as I can set the color and intensity of the LEDs besides just on/off...

Here is a GIF of my attempt of simple color switching with an addressable LED strip for now:

In this, I cannot set any direction of travel and the effect depends on using a bit of imagination...

Although it might seem difficult to provide a good effect with just 2 color channels, I want an opinion if it is possible or not?

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Kiteman2 years ago

If every other LED is wired to be on at the same time, you are stuck with the pattern in your GIF.

Antzy Carmasaic (author)  Kiteman2 years ago

But I have power over more than just On-Off. I can control color and intensity.

What if I have blend the red into green(red fades to yellow to green) followed by green into red?

What if I imagine the space inbetween the LEDs to be dead LEDs and push a third color(blue) across them. So the pattern becomes:

R b G x R b G x R

R x B x R x B x R

R x G b R x G b R

B x G x B x G x B

R b G x R b G x R

(R = red; G = Green; B = Blue; x = dead space imaginary LED; b = Blue in imaginary LED)

Now there are 4 states instead of 2. So maybe a better effect(or worse)...

2 years ago

Ah, I see.

Antzy Carmasaic (author)  Kiteman2 years ago

It seems pretty difficult but I'll try a few ideas that pop into my head. Thanks for helping out Kiteman....

Downunder35m2 years ago

You want the "Knight Rider" effect but with different colors I assume?
My programming skills are quite rusty but the basics steps I might use:
Set a register for the color information, either for 3, 8 or more LED's, this allows a rainbow effect for the lights.
But this would require a different wiring.
Sadly the same is true for the wandering effect of the light.
With your current setup you are limited to blinking as addressing the color change will only affect two LED's.
You can get cheap IC's for the Night Rider effect and if I am not mistaken even some Instructables.
If you add the color change you should be good to go.
Using an Arduino or micro controller it would also be possible to combine the color change and wandering light by addressing the LED's as bytes.

Antzy Carmasaic (author)  Downunder35m2 years ago

Something like that but Knight Rider effect uses multiple individually controlled LEDs. What I'm going for is only 2 LEDs mutiplied over and over. So what happens in one gets reflected in it's multiples. But other comments have made me realize that it is very difficult to impossible with my setup. Thanks for your input... :)

caitlinsdad2 years ago

The optical effect might need to have 3 pixels so you have some distance between the pixels to look like it is moving along, otherwise what the brain interprets is just flashing on and off and no movement. Can you put a delay or slow fade/ramp up on every third pixel? Maybe vary the delay on sets of 3 with different capacitor values for each of the 3?

Antzy Carmasaic (author)  caitlinsdad2 years ago

That's the problem: I'm limited to 2 pixels only. It's possible with 3 but in this case I can only have 2. So was looking if anyone had any ideas to lessen the blinking effect and more like travelling effect... Guess it's a dead end. :(