Light

The Light class constructs objects that represent a single analog or digital light light component attached to the physical board. Light sensors are used to measure ambient or direct light intensity.

Supported Light sensors:

• Photoreistors
  • Sparkfun
    • Mini Photocell
• TSL2561
  • Adafruit
  • Sparkfun
• EV3 Color & Light Sensor
  • Lego
• NXT Color Sensor
  • Lego

This list will continue to be updated as more devices are confirmed.

Parameters

• pin A Number or String address for the Light pin (analog).

• options An object of property parameters.

  Property	Type	Value/Description	Default	Required
  pin	Number, String	Analog Pin. The Number or String address of the pin the light is attached to, ie. "A0"		No
  controller	string	DEFAULT, EVS_EV3, TSL2561. The Name of the controller to use.		no
  freq	Number	Milliseconds. The rate in milliseconds to emit the data event	25ms	no
  threshold	Number	Any. The change threshold (+/- value).	1	no

Shape

Property Name	Description	Read Only
id	A user definable id value. Defaults to a generated uid	No
pin	The pin address that the Light is attached to	No
threshold	The change threshold (+/- value). Defaults to 1	No
value	Raw value	Yes
level	Intensity level 0-1 (%)	Yes

Component Initialization

Analog Light (Most common case)

new five.Light("A0");

Usage

Analog Light

var five = require("johnny-five");
var board = new five.Board();

board.on("ready", function() {
  var light = new five.Light("A0");
  light.on("change", function() {
    console.log(this.level);
  });
});

API

• within(range, handler) When value is within the provided range, execute callback.

  var light = new five.Light("A0");
  
  light.within([ 0.10, 0.20 ], function() {
  
    // This is called when the light's value property falls within 100-200
  
  });

Events

• change The "change" event is emitted whenever the value of the light changes more than the threshold value allows.
• data The "data" event is fired as frequently as the user defined freq will allow in milliseconds.