A set of patterns for the Espruino to use a WS2811 RGB LED strips which change with the press of the on-board button. Defaulted to connect to pin B15 and 50 LEDs

espruino_coloured_lights.js

/*var sensor = require("HC-SR04").connect(C6,C7,function(dist) {
  console.log(dist+" cm away");
});
setInterval(function() {
  sensor.trigger(); // send pulse
}, 500);
*/

SPI2.setup({baud:3200000, mosi:B15});
var rgb = new Uint8Array(50*3);

var pos=0;

function lightsOff() {
  clearInterval(cycle);
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
    rgb[i  ] = 0;
    rgb[i+1] = 0;
    rgb[i+2] = 0;
  }
  SPI2.send4bit(rgb, 0b0001, 0b0011);
}

var patterns = [];
//patterns.push(lightsOff);
patterns.push(function() {
  // Fading white lights
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     var col = (Math.sin(i+pos*0.2)+1) * 127;
     rgb[i  ] = col;
     rgb[i+1] = col;
     rgb[i+2] = col;
  }
});
patterns.push(function() {
  // Low red light
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     var col = 10;
     rgb[i  ] = col;
     rgb[i+1] = 0;
     rgb[i+2] = 0;
  }
});
patterns.push(function() {
  // Medium red light
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     var col = 50;
     rgb[i  ] = col;
     rgb[i+1] = 0;
     rgb[i+2] = 0;
  }
});
patterns.push(function() {
  // Medium red light 2
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     var col = 100;
     rgb[i  ] = col;
     rgb[i+1] = 0;
     rgb[i+2] = 0;
  }
});
patterns.push(function() {
  // Full red light
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     var col = 255;
     rgb[i  ] = col;
     rgb[i+1] = 0;
     rgb[i+2] = 0;
  }
});
patterns.push(function() {
  // Low green light
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     var col = 50;
     rgb[i  ] = 0;
     rgb[i+1] = col;
     rgb[i+2] = 0;
  }
});
patterns.push(function() {
  // Low blue light
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     var col = 50;
     rgb[i  ] = 0;
     rgb[i+1] = 0;
     rgb[i+2] = col;
  }
});
patterns.push(function() {
  // Fading colours
  pos++;
  for (var i=0;i<rgb.length;i+=3) {
     rgb[i  ] = (1 + Math.sin((i+pos)*0.1324)) * 127;
     rgb[i+1] = (1 + Math.sin((i+pos)*0.1654)) * 127;
     rgb[i+2] = (1 + Math.sin((i+pos)*0.1)) * 127;
  }
});
patterns.push(function() {
  // Random blue lights
  for (var i=0;i<rgb.length;i+=3) {
     rgb[i  ] = 0;
     rgb[i+1] = 0;
     rgb[i+2] = Math.random()*255;
  }
});
var getPattern = patterns[0];
function doLights() {
  getPattern();
  SPI2.send4bit(rgb, 0b0001, 0b0011);
}

var patternNumber = 0;
function changePattern() {
  patternNumber = (patternNumber+1) % patterns.length;
  getPattern = patterns[patternNumber];
}

setWatch(changePattern, BTN, { repeat: true, edge:'falling' });
cycle = setInterval(doLights,50);