WS2801-Pi

WS2801-Pi is a module for controlling WS2801 LED strips with a Raspberry Pi via SPI.

Installation

• Install this module
• Activate SPI

Documentation

The documentation can be found here.

Wiring

Raspberry Pi	led strip
GND	GND
SCLK	Clock
MOSI	Data

You should connect the GND and the V+ of the led strip to an external power supply.

Config

Config	Explanation	Type	Default
debug	Run without sending signals to the gpio ports.	boolean	false
automaticRendering	Automatically run show() after changing Leds.	boolean	false
clockSpeed	Set the desired clockSpeed.	ClockSpeed	2e6 | 2MHz

The clockSpeed can also be changed via ledController.clockSpeed.

Usage

import LedController from 'ws2801-pi';
// const LedController = require('ws2801-pi').default;

const amountOfLedsOnStrip = 100;

const ledController = new LedController(amountOfLedsOnStrip);

let color = {
  red: 255,
  green: 120,
  blue: 0,
};

// Set color of whole led strip
ledController.fillLeds(color);
ledController.show();

color.red = 0;
color.green = 0;
color.blue = 255;

// Set color of single led
ledController.setLed(0, color);
ledController.show();

// Clear led strip (turn all leds off)
ledController
  .clearLeds()
  .show();

Hint: Make sure to call show() after changing leds in order to physically change the leds.

Hint: If automaticRendering is set show() does not have to be called. The rendering can then be awaited via ledController.renderPromise.

Example Animation

import LedController from 'ws2801-pi';
// const LedController = require('ws2801-pi').default;

const amountOfLedsOnStrip = 100;

const ledController = new LedController(amountOfLedsOnStrip);

async function wait(ms) {
  return new Promise((resolve) => {
    setTimeout(resolve, ms);
  });
}

async function animate() {
  let colors = [
    {red: 255, green: 0, blue: 0},
    {red: 0, green: 255, blue: 0},
    {red: 0, green: 0, blue: 255},
    {red: 255, green: 255, blue: 0},
    {red: 255, green: 0, blue: 255},
    {red: 0, green: 255, blue: 255},
    {red: 0, green: 2505, blue: 0},
  ];

  for (const color of colors) {
    for (let ledIndex = 0; ledIndex < amountOfLedsOnStrip; ledIndex++) {
      ledController
        .setLed(ledIndex, color)
        .show();

      await wait(30);
    }

    await wait(300);
  }
}
animate();