Arduino NG User Manual

it to the bind method. bind creates a new function and sets the new function’s
this keyword to the value you passed to bind originally. Using bind , you can
define a function now, but make sure that it has a certain context when you
actually call it.
When working with event handlers, this is often necessary. Users of the Seri-
alDevice class should be able to pass their own callback functions, but they
should be executed in the class’ context. You’ll see how this works in a minute.
At the end of the constructor, we define three instance variables that are all
instances of the chrome.Event class.
10
This class provides some nice features to
define and dispatch events within Chrome apps. We use it to define the three
events that users of our SerialDevice class can listen for. Now users can register
for readLine events using the onReadLine property.
The next three methods of the SerialDevice class implement everything needed
for connecting and disconnecting serial devices:
ChromeApps/SerialDevice/js/serial_device.js
SerialDevice.prototype.connect = function() {
Line 1
chrome.serial.connect(
-
this.path,
-
{ bitrate: this.baudRate },
-
this.onConnectComplete.bind(this))
5
};
-
-
SerialDevice.prototype.onConnectComplete = function(connectionInfo) {
-
if (!connectionInfo) {
-
console.log("Could not connect to serial device.");
10
return;
-
}
-
this.connectionId = connectionInfo.connectionId;
-
chrome.serial.onReceive.addListener(this.boundOnReceive);
-
chrome.serial.onReceiveError.addListener(this.boundOnReceiveError);
15
this.onConnect.dispatch();
-
};
-
-
SerialDevice.prototype.disconnect = function() {
-
if (this.connectionId < 0) {
20
throw "No serial device connected.";
-
}
-
chrome.serial.disconnect(this.connectionId, function() {});
-
};
-
10. https://developer.chrome.com/extensions/events
Appendix 4. Controlling the Arduino with a Browser • 276
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Arduino NG Specifications

General

Brand	Arduino
Model	NG
Category	Motherboard
Language	English