Remote Control WS2811 Beach Sign Guide

Description

Introduction

In the interest of learning from failures as much as successes this failed version of the remote control beach sign is documented below so that others may learn from my mistakes and that perhaps someone will know precisely why this failed and I too can learn something.

Related Project Logs

Failed Project

The video above illustrates the flickering issue experienced towards the end of the strand (top letters). This seemed to only happen when there was a high refresh rate and/or the use of PWM. At full brightness on white the LED's would flicker every few seconds, on the lowest brightness they would flicker continuously.

Neopixels

Adafruit Neopixels are individually addressable LED's based on the WS2811 or WS2812 protocols.

First the pins were bent at a 90 degree angle and then fanned out slightly to make the pins easier to solder.

Postmortem

I tried the following things to try and get this to work with no real degree of success.

  • At first it seemed that maybe the second half of the strip was not getting enough power after being fed through the first half of the strip and so I ran an additional power wire directly from the input source to the second half. This actually seemed to make things worse.
  • Some guides and documentation recommend the use of a resister before the first LED and even in between each pixel however, this has no effect.
  • It seemed like perhaps one of the pixels was bad and giving out corrupted data to the rest of the strip however, having rewired the entire strip several times to rule this out I can say this is not the case.
  • Another issue could have been that the metal frame housing the pixels was not grounded, after connecting this to the common ground there was again no change.

I have read that perhaps using thin wire is to blame altough this seems unlikely given the pins of the LED are thin and the wire connecting the WS2811 chip to the LED itself internally are even thinner. Other guides say that a decoupling capacitor between the power input to each pixel could also solve this issue but I did not have 24 of the correct type to try this.

Although I don't think this is an inherent issue with these Neopixels the Adafruit product page and accompanying guides don't really mention steps that should be taken when connecting this amount of LED's though it's possible I missed this information. Their demo shows 5 of them connected on a breadboard and being someone with a fair degree of technical skill after a day of troubleshooting and not being able to solve this I simply cut my losses and moved on to another type of strip.

Parts

Creator

Remote Control WS2811 Beach Sign Guide was created by Travis Brown, email: WarriorRocker@gmail.com.