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<div class="title">Timer interface </div> </div>
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<div class="textblock"><p>Timer interface is designed to use internal timers in sound hardware, but it can be driven with any timer.</p>
<h1><a class="anchor" id="timer_general_overview"></a>
General overview</h1>
<p>The timer implementation uses ring buffer to store information about timing events. In this buffer is recorded count of ticks and current tick resolution in nanoseconds.</p>
<h1><a class="anchor" id="timer_open"></a>
Opening</h1>
<p>Timer devices can be opened in two ways. When <a class="el" href="group___timer.html#gac2c50bf6045560bc13aab81f25b2b740">SND_TIMER_OPEN_NONBLOCK</a> flag is used, then the open functions return immediately with -EBUSY error code when resources are occupied with another application. When <a class="el" href="group___timer.html#gac2c50bf6045560bc13aab81f25b2b740">SND_TIMER_OPEN_NONBLOCK</a> is not used (by default) the open functions block the application requesting device until resources are not free.</p>
<h1><a class="anchor" id="timer_events"></a>
Events</h1>
<p>Events are read via <a class="el" href="group___timer.html#ga724ada94d0bc3564ad77973c0a084682" title="read bytes using timer handle">snd_timer_read()</a> function.</p>
<h1><a class="anchor" id="timer_examples"></a>
Examples</h1>
<p>The full featured examples with cross-links:</p>
<dl class="section user"><dt>Simple timer test program</dt><dd><a class="el" href="_2test_2timer_8c-example.html#example_test_timer">example code </a> </dd></dl>
<dl class="section user"><dt></dt><dd>This example shows opening a timer device and reading of timer events. </dd></dl>
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