Simulates an LED strip and allows very NeoPixel-like access
Click here for a ready-to-use online simulator
Your browser needs:
- HTML: HTML5
- CSS: CSS3
- JavaScript: ECMAScript6 The newest version of Firefox/Chrome/Opera/Safari/Edge should work fine.
You'll wirte your code in JavaScript. But the syntax of original Adafruit_NeoPixel c++ class is simlulated as good as possible.
Your original C++ code could for example translate like this:
C++
#define PIN 10;
#define NUM_LEDS = 60;
Adafruit_NeoPixel strip = Adafruit_NeoPixel(NUM_LEDS, PIN, NEO_GRB + NEO_KHZ800);
void setup() {
strip.begin();
strip.show();
strip.setPixelColor(0, Color(255,0,0));
strip.show();
}JavaScript
var PIN = 10;
var NUM_LEDS = 60;
var strip = new Adafruit_NeoPixel(NUM_LEDS, PIN, NEO_GRB + NEO_KHZ800);
function setup() {
strip.begin();
strip.show();
strip.setPixelColor(0, Color(255,0,0));
strip.show();
}I implemented the functions millis(), micros(), delay() as well as the callback fucntions setup() and loop().
About delay(): Use it wisely. It will freeze it's thread while it is running. To prevent UI or whole browser freezing, run your code in a new thread (worker).
- Create a new folder
- copy Adafruit_NeoPixel.js into the folder
- copy Adafruit_NeoPixel.css into the folder
- create a new .html file with the following contents:
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css" href="Adafruit_NeoPixel.css">
<script src="Adafruit_NeoPixel.js"></script>
<script>
//Your code goes here
//For example:
//function setup() {
//
//}
//function loop() {
//
//}
</script>
</head>
<body>
<!-- In this section you can create new led strips. Remember to define a different "data-pin" for every led strip and use the pin numbers in your code. -->
<div class="ledStrip" data-pin="10"></div>
</body>
</html>The BasicExample.html file contains an example.
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css" href="Adafruit_NeoPixel.css">
<script src="Adafruit_NeoPixel.js"></script>
<script>
//USER
const PIN = 10
const NUM_LEDS = 60
const BRIGHTNESS = 255
//ws2812b, arduino pro mini
var strip = new Adafruit_NeoPixel(NUM_LEDS, PIN, NEO_GRB + NEO_KHZ800)
function setup() {
strip.setBrightness(BRIGHTNESS)
strip.begin()
strip.show()
}
var red = strip.Color(255, 0, 0)
var yellow = strip.Color(255, 255, 0)
var blue = strip.Color(0, 0, 255)
var colors = [red,yellow,blue]
var currentColorIndex = 0
function loop() {
var animationDone = colorWipe(colors[currentColorIndex])
if (animationDone)
currentColorIndex = (currentColorIndex>=colors.length-1 ? 0 : currentColorIndex+1)
}
function colorWipe(color) {
var now = millis()
if (now > colorWipe.lastUpdate+colorWipe.delay) {
strip.setPixelColor(colorWipe.currentLed, color)
strip.show()
colorWipe.currentLed = colorWipe.currentLed>=strip.numPixels()-1 ? 0 : colorWipe.currentLed+1
colorWipe.lastUpdate = now
if (colorWipe.currentLed === 0)
return true;
}
return false
} //c++-like static variables for this fucntion:
colorWipe.delay = 10
colorWipe.lastUpdate = 0
colorWipe.currentLed = 0
</script>
</head>
<body>
<div class="ledStrip" data-pin="10"></div>
</body>
</html>