In our last blog post we showed you how to interact with the GPIO ports and how to turn on one LED. Now for some more magic lights we create a little Node.js application that drives a NeoPixel LED strip from Adafruit in a Docker container.
Thanks to the latest improvements now both Raspberry Pi B/B+ and the new Pi 2 B can drive the NeoPixel LED strips from Adafruit with just a level shifter. So it’s time to put this into Docker for easier deployment.
The NeoPixel (or WS2812) LED’s are programmable RGB LED’s that receive their RGB value with a single serial wire.
Let’s have a look at the wiring first. The Raspberry Pi can create the serial signal on GPIO Pin 18 trough PWM/DMA. But the signal level has to be shifted from 3.3V to 5V for the LED strip. I have used a Adafruit Level Shifter Breakout Board, but a 74AHCT125 level converter could be used as well.
Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.