Datasheet

The above declares two distinct NeoPixel objects, one each on pins 5 and 6, each containing 16 pixels and using the

implied default type (NEO_KHZ800 + NEO_GRB).

Can I connect multiple NeoPixel strips to the same Arduino pin?

In many cases, yes. All the strips will then show exactly the same thing. This only works up to a point though…four

strips on a single pin is a good and reliable number. If you need more than that, individual NeoPixels can be used as

buffers to “fan out” to more strips: connect one Arduino pin to the inputs of four separate NeoPixels, then connect

each pixels’ output to the inputs of four strips (or fewer, if you don’t need quite that many). If the strips are 10 pixels

long, declare the NeoPixel object as having 11 pixels. The extra “buffer” pixels will be at position #0 — just leave

them turned off — and the strips then run from positions 1 through 10.

I'm getting the wrong colors. Red and blue are swapped!

When using through-hole 8mm NeoPixels (or V1 Flora pixels), use NEO_RGB for the third parameter in the

Adafruit_NeoPixel declaration. For all other types of NeoPixels, use NEO_GRB.

The colors fall apart when I use setBrightness() repeatedly!

See note above; setBrightness() is designed as a one-time setup function, not an animation effect.

Also see the “Advanced Coding” page — there’s an alternative library that includes “nondestructive” brightness

adjustment, among other features!

Pixels Gobble RAM

Each NeoPixel requires about 3 bytes of RAM. This doesn’t sound like very much, but when you start using dozens or

even hundreds of pixels, and consider that the mainstream Arduino Uno only has 2 kilobytes of RAM (often much less

after other libraries stake their claim), this can be a real problem!

For using really large numbers of LEDs, you might need to step up to a more potent board like the Arduino Mega or

Due. But if you’re close and need just a little extra space, you can sometimes tweak your code to be more RAM-

efficient. This tutorial has some pointers on memory usage.