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<h1>Ring Oscillators</h1>
<p>We started this page to catalog tests of speed for a variety of microprocessors and electronics modules. Here we define speed as how fast information can transit from external electronics into the core where microcode is running and back out again. A good way to test this is by constructing a ring oscillator, which simply sends token back and forth, producing a waveform that can be measured with an oscilloscope.</p>
<h2>GPIO</h2>
<p>To measure speed across a GPIO layer, we use a logic level as out token.</p>
<div id='gpio'></div>
<h2>RF</h2>
<p>To measure speed across a radio link, we use the smallest supported packet.</p>
<div id='rf'></div>
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