NeoPixel, Contol single LED in strand?

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ksaccullo
 
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NeoPixel, Contol single LED in strand?

Post by ksaccullo »

In a long (~ 200 to 300) array of Neopixel (or APA102 LEDS) is their any creative way to control a single LED? It looks like the data just cascades to the next NeoPixel in the chain.
I'm looking to string these in a tree and want them to twinkle, not look like a Vegas light show. Twinkle meaning "randomly" controlling individual Neopixels to slowly fade on and off. Main controller would be a PIC.

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Franklin97355
 
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Re: NeoPixel, Contol single LED in strand?

Post by Franklin97355 »

Code: Select all

 pixels.setPixelColor(i, pixels.Color(0,150,0)); // Moderately bright green color
 pixels.show(); // This sends the updated pixel color to the hardware..
Will light pixel #i to color (0,150,0)

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ksaccullo
 
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Re: NeoPixel, Contol single LED in strand?

Post by ksaccullo »

I’m still unclear. Can you point me to an assembly language example of your code?

What I get from your example the serial data string would look like the attached picture (trying to turn neo pixel # 3 on to ~ half bright green). But from how I read the data sheet, the third data group would cause all the neo pixels (one at a time) to turn green.
NeoPixleSerial.jpg
NeoPixleSerial.jpg (58.58 KiB) Viewed 442 times

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Franklin97355
 
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Re: NeoPixel, Contol single LED in strand?

Post by Franklin97355 »

The data is passed to the string and each pixel strips off the leading bits and passes the rest down the line. The third packet will be on the front only at the third pixel.

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ksaccullo
 
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Re: NeoPixel, Contol single LED in strand?

Post by ksaccullo »

Now I got it. I was over complicating a very simple concept.
Thank you.

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