Sonar

The Sonar class constructs objects that represent a single analog or I2C Sonar sensor attached to the physical board. This class works with:

• Maxbotix Analog Sonar

  • Any

• Devantech I2C Sonar

  • SRF02
  • SRF08
  • SRF10

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

NOTE: The Sonar class is deprecated. Please use the Proximity class.

Parameters

• pin A String address for the Sonar pin (analog only).

• options An object of property parameters.

  Property	Type	Value/Description	Default	Required
  pin	Number, String	Any pin. The Number or String address of the pin the sonar is attached to, ie. “A0” or “I1”		yes (for analog)
  controller	String	“SRF02”, “SRF08”. A String model id of a Sonar device (I2C only), ie. “SRF02”, “SRF08”, “SRF10”		yes (for I2C)
  freq	Number	Milliseconds. The frequency in ms of data events.	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 Sonar is attached to	No
cm	Value of current reading in centimeters.	Yes
inches	Value of current reading in inches.	Yes
value	Value of current reading in cm.	No

Component Initialization

Maxbotix Analog Sonar

// Create an analog Sonar object:
// 
//   - attached to pin "A0"
//
new five.Sonar({
  pin: "A0", 
});

I2C Sonar

// Create an I2C Sonar object:
// 
//   - use device model "SRF10"

new five.Sonar({
  controller: "SRF10"
});

Usage

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

board.on("ready", function() {
  var sonar = new five.Sonar("A0");

  sonar.on("data", function() {
    console.log("inches     : " + this.in);
    console.log("centimeters: " + this.cm);
    console.log("-----------------------");
  });
});

API

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

var sonar = new five.Sonar({
  device: "SRF10"
});

sonar.within([ 5, 10 ], "inches", function() {
  
  // This is called when the sonar detects an object 5-10 inches away

});

Events

• change The "change" event is emitted whenever the value of the sonar changes more then the threshold value allows.

• data The "data" event is fired as frequently as the user defined freq will allow in milliseconds. ("data" replaced the "read" event)