README

rpi-ws281x-led

A NodeJS Addon wrapper for the rpi_ws281x library. Contains type declarations.

Installing

You can add this package to your own project using

npm install rpi-ws281x-led

and then importing it with

import Driver from 'rpi-ws281x-led';

Notes

This library is meant to be used on the Raspberry PI. If the package is installed on an unsupported OS, an interface without bindings will be provided.
Root privledges are required for the driver to work, start the nodejs process as sudo.

Usage Example

Setup a dual channel driver with two different types of strips.

import Driver from 'rpi-ws281x-led';

// Create the driver. It automatically initializes the underlying components.
const driver = new Driver({
  freq: 800000,
  channels: [
    {
      gpio: 18,
      count: 100,
      type: StripType.WS2812_STRIP,
      brightness: 64,
    },
    {
      gpio: 13,
      count: 200,
      type: StripType.WS2811_STRIP_RGB,
      brightness: 255,
    },
  ],
});

const channel1 = driver.channels[0];

channel1.leds[50] = 0xffff00;
channel1.brightness = 255;
channel1.render(); // OR driver.render();

channel1.leds = new Uint32Array(100).fill(0x000000);
channel1.render();

Driver Configuration

`Driver -> constructor(config: DriverConfiguration): Driver`

Creates a new Driver with the provided configuration.

Params:

'config' - The configurations for the driver.

interface DriverConfiguration {
  dma?: number; // Default: 10
  frequency?: number; // Default: 800000
  channels: ChannelOptions[];
}

interface ChannelConfiguration {
  gpio?: number; // Default: 18 or 13
  invert?: boolean; // Default: false
  count: number;
  type?: StripType; // Default: StripType.WS2812_STRIP
  brightness?: number; // Default: 255
}

Driver Configuration

dma - The DMA channel to use for the leds.
frequency - The frequency of the PWM channel.

Channel Configuration

gpio - The GPIO pin the driver should use.
invert - Whether to invert the output signal.
count - The number of leds to initialize the driver with.
type - The type of the strip.
brightness - The brighness of the strip.

A channel will be created for every object with a count in the configuration. The GPIO pin defaults to 18 and then 13 if it is taken.

StripType

The StripType enum is defined as follows. Use these values or the enum to setup the strip.

enum StripType {
  SK6812_STRIP_RGBW = 0x18100800,
  SK6812_STRIP_RBGW = 0x18100008,
  SK6812_STRIP_GRBW = 0x18081000,
  SK6812_STRIP_GBRW = 0x18080010,
  SK6812_STRIP_BRGW = 0x18001008,
  SK6812_STRIP_BGRW = 0x18000810,
  SK6812_SHIFT_WMASK = 0xf0000000,
  WS2811_STRIP_RGB = 0x00100800,
  WS2811_STRIP_RBG = 0x00100008,
  WS2811_STRIP_GRB = 0x00081000,
  WS2811_STRIP_GBR = 0x00080010,
  WS2811_STRIP_BRG = 0x00001008,
  WS2811_STRIP_BGR = 0x00000810,
  WS2812_STRIP = WS2811_STRIP_GRB,
  SK6812_STRIP = WS2811_STRIP_GRB,
  SK6812W_STRIP = SK6812_STRIP_GRBW,
}

License

This project is licensed under the MIT License - see the LICENSE.md file for details.

Usage no npm install needed!