user3916: I'm trying to retrieve / synchronize time from PC using this Time lib function: 
setSyncProvider( requestSync);  //set function to call when sync required

It sends ASCII BEL (07) character to PC, but I'm getting no response using Serial.available. What am I missing? 
Do I have to run a specific app on the PC to get a response? The docs do not specify that. 

user42: Yes, you'll need something running on the PC which is monitoring the serial port, and which will provide a response in the appropriate format.
The download on this page contains a Processing sketch which will do this for you. After you've unzipped it, look in Time/Examples/Processing/SyncArduinoClock. Open the sketch in Processing, run it, and then start your Arduino.
If you're not familiar with it, Processing is a free programming language / environment based on Java. It's aimed largely at beginners and non-programmers, and is quite commonly used for communicating with Arduino projects via Serial. You can download it here:

http://www.processing.org


3916: <p>I'm trying to retrieve / synchronize time from PC using this Time lib function: </p>

<pre><code>setSyncProvider( requestSync);  //set function to call when sync required
</code></pre>

<p>It sends ASCII BEL (07) character to PC, but I'm getting no response using <code>Serial.available</code>. What am I missing? </p>

<p>Do I have to run a specific app on the PC to get a response? The docs do not specify that. </p>
 42: <p>Yes, you'll need something running on the PC which is monitoring the serial port, and which will provide a response in the appropriate format.</p>

<p>The download on <strong><a href="http://playground.arduino.cc/code/time" rel="nofollow">this page</a></strong> contains a Processing sketch which will do this for you. After you've unzipped it, look in <code>Time/Examples/Processing/SyncArduinoClock</code>. Open the sketch in Processing, run it, and then start your Arduino.</p>

<p>If you're not familiar with it, Processing is a free programming language / environment based on Java. It's aimed largely at beginners and non-programmers, and is quite commonly used for communicating with Arduino projects via Serial. You can download it here:</p>

<ul>
<li><a href="http://www.processing.org" rel="nofollow">http://www.processing.org</a></li>
</ul>
