fred-feng / node-dmx

Control any DMX512 compatible lighting system with node.js via FTDI USB-RS485 cable.

Description

Control any DMX512 compatible lighting system with node.js via FTDI USB-RS485 cable.

Requirements

• node.js
• Сompatible USB-RS485 cable
• libftdi1 and libftdi-dev packages or libFTDI library

Install

npm install git://github.com/unkernet/node-dmx.git

Use

This sample code searches for the first available device and starts turn the light on and off infinitely

var DMX = require('./dmx_native.node');
var list = DMX.list();
console.log('Found ' + list.length + ' devices');

if (list.length > 0) {
  try {
    var dmx = DMX.DMX(0);
  } catch (e) {
    console.error(e.message);
    process.exit();
  }
  dmx.setHz(20);
  dmx.step(5);
  var val = [255], odd=true;
  setInterval(function(){
    dmx.set(val);
    val.unshift(odd =! odd ? 255 : 0);
    if (val.length > 512) val.pop();
  }, 3000);
}

Common issues

• I have ftdi_usb_open_dev failed error
  Try to sudo rmmod ftdi_sio

API

• list () Return an array with all available devices, or empty array if no devices found.
• DMX (index) Open device with specified index and return a DMX object. 0 is for the first.

DMX object:

• start () Begin transmission of DMX packets
• stop (wait) Stop transmission of DMX packets. If wait is true, wait until the end of thread.
• step (step) Set the maximum level change in one cycle. Default 255 means immediately. Useful for slow light transactions.
• setHz (Hz) Set count of DMX packets transmitted per second. From 1 to 50, default 25. More than 38 may cause blinking due to transmission errors.
• set (value) Set value of channels. If the number specified will set all 512 channels to same level. If array, level will be set for the first value.length channels.