Modifications

The [http://www.adafruit.com/datasheets/WS2812.pdf WS2812 datasheet] explains the data transmission protocol. This is a self-clocking signal — there’s only one wire, not separate data and clock lines. “1” and “0” bits are indicated by varying the duty cycle of a fixed-frequency square wave.

The [http://www.adafruit.com/datasheets/WS2812.pdf WS2812 datasheet] explains the data transmission protocol. This is a self-clocking signal — there’s only one wire, not separate data and clock lines. “1” and “0” bits are indicated by varying the duty cycle of a fixed-frequency square wave.

[[Fichier:NeoPixel-UserGuide-YourLib-01.jpg]]

[[Fichier:NeoPixel-UserGuide-YourLib-01.png]]

There’s a math goof in the datasheet’s timing values. Use these figures instead:  

There’s a math goof in the datasheet’s timing values. Use these figures instead:  

[[Fichier:NeoPixel-UserGuide-YourLib-02.jpg]]

[[Fichier:NeoPixel-UserGuide-YourLib-02.png]]

Note that there’s nearly 25% “wiggle room” in the timing. So if your code can’t match the recommended times exactly, it’s usually okay.

Note that there’s nearly 25% “wiggle room” in the timing. So if your code can’t match the recommended times exactly, it’s usually okay.

There are three bytes of data for each pixel. These should be issued in green, red, blue order, with the most-significant bit first.

There are three bytes of data for each pixel. These should be issued in green, red, blue order, with the most-significant bit first.

[[Fichier:NeoPixel-UserGuide-YourLib-03.jpg]]

[[Fichier:NeoPixel-UserGuide-YourLib-03.png]]

The data for pixel #0 (nearest the microcontroller) is issued first, then pixel #1, and so forth to the furthest pixel. This does not operate like a traditional shift register!

The data for pixel #0 (nearest the microcontroller) is issued first, then pixel #1, and so forth to the furthest pixel. This does not operate like a traditional shift register!