WS 2811 lights flickering

Question

I'm working on a project involving a bunch of daisy-chained WS2811 lights and I'm noticing significant flickering on the ones at the end (lights #16-30 in a chain of 30).

Right now, the circuit is a 3.7V lithium ion battery connected to both a 3.3V Gemma Arduino and also in parallel to the lights. I'm using thick 16 AWG stranded wire to run big "central lines" for power and ground and then soldering smaller 22 AWG wire from those central lines to the individual LEDs. At peak, the longest cable run is about 4 feet from the battery to an LED.

The data lines are obviously daisy chained to each other, and I have a 330 Ohm resistor between the data line and the first LED as recommended by Adafruit.

Here's a video of the flickering.

Any idea what might be going on or how I should debug this?

Thanks!

Answer 1

It turns out that WS281X reshapes the signal on output, therefore the timing of the bits has to be reasonably tight otherwise a reset signal may be generated within the pulse train by further devices. Verify your code to make sure that the pixel timing is as expected by them.

"NeoPixels Revealed: Why you should give your bits room to breathe"