This example uses a 16 LED strip and a custom rainbow calculator to create a nice rainbow over a static area. This example uses a custom firmata.
To install the custom firmata, see the Installation Guide.
Wire the neopixel panel up as shown below.
var five = require("johnny-five");
var pixel = require("node-pixel");
var opts = {};
opts.port = process.argv[2] || "";
var board = new five.Board(opts);
var strip = null;
board.on("ready", function() {
console.log("Board ready, lets add light");
// setup the node-pixel strip.
strip = new pixel.Strip({
data: 6,
length: 16, // number of pixels in the strip.
board: this,
controller: "FIRMATA"
});
strip.on("ready", function() {
console.log("Strip ready, let's go");
staticRainbow();
});
function staticRainbow(){
console.log('staticRainbow');
var showColor;
for(var i = 0; i < strip.length; i++) {
showColor = colorWheel( ( i*256 / strip.length ) & 255 );
strip.pixel( i ).color( showColor );
}
strip.show();
}
// Input a value 0 to 255 to get a color value.
// The colours are a transition r - g - b - back to r.
function colorWheel( WheelPos ){
var r,g,b;
WheelPos = 255 - WheelPos;
if ( WheelPos < 85 ) {
r = 255 - WheelPos * 3;
g = 0;
b = WheelPos * 3;
} else if (WheelPos < 170) {
WheelPos -= 85;
r = 0;
g = WheelPos * 3;
b = 255 - WheelPos * 3;
} else {
WheelPos -= 170;
r = WheelPos * 3;
g = 255