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<p class='vspace'></p><h2>shiftIn()</h2>
<h4>Description</h4>
<p>Shifts in a byte of data one bit at a time. Starts from either the most (i.e. the leftmost) or least (rightmost) significant bit. For each bit, the clock pin is pulled high, the next bit is read from the data line, and then the clock pin is taken low.
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<p class='vspace'></p><p>Note: this is a software implementation; Arduino also provides an <a class='wikilink' href='SPI.html'>SPI library</a> that uses the hardware implementation, which is faster but only works on specific pins.
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<p class='vspace'></p><h4>Syntax</h4>
<p>shiftIn(dataPin, clockPin, bitOrder)
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<p class='vspace'></p><h4>Parameters</h4>
<p>dataPin: the pin on which to output each bit (<em>int</em>)
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<p class='vspace'></p><p>clockPin: the pin to toggle once the <strong>dataPin</strong> has been set to the correct value (<em>int</em>)
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<p class='vspace'></p><p>bitOrder: which order to shift out the bits; either <strong>MSBFIRST</strong> or <strong>LSBFIRST</strong>.<br />(Most Significant Bit First, or, Least Significant Bit First)
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<p class='vspace'></p><h4>Returns</h4>
<p>the value read (<em>byte</em>)
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<p class='vspace'></p><h4>See also</h4>
<ul><li><a class='wikilink' href='ShiftOut.html'>shiftOut()</a>
</li><li><a class='wikilink' href='SPI.html'>SPI</a>
</li></ul><p class='vspace'></p><p><a class='wikilink' href='index.html'>Reference Home</a>
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<p class='vspace'></p><p><em>Corrections, suggestions, and new documentation should be posted to the <a class='urllink' href='http://arduino.cc/forum/index.php/board,23.0.html' rel='nofollow'>Forum</a>.</em>
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<p class='vspace'></p><p>The text of the Arduino reference is licensed under a
<a class='urllink' href='http://creativecommons.org/licenses/by-sa/3.0/' rel='nofollow'>Creative Commons Attribution-ShareAlike 3.0 License</a>. Code samples in the reference are released into the public domain.
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