195 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
		
		
			
		
	
	
			195 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
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								<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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								<html>
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								<head>
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								  <title>Arduino - Reference </title>
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								  <link rel='stylesheet' href='arduino.css' type='text/css' />
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								</head>
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								<body>
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								<div id="pageheader">
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								  <div class="title"><a href="http://www.arduino.cc"/>Arduino</a></div>
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								  <div class="search">
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								  <div style="float: left;">
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								  <p><a class='wikilink' href='http://arduino.cc/en/Main/Buy'>Buy</a>
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								<a class='wikilink' href='http://arduino.cc/en/Main/Software'>Download</a>
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								<a class='wikilink' href='Guide_index.html'>Getting Started</a>
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								<a class='wikilink' href='http://arduino.cc/en/Tutorial/HomePage'>Learning</a>
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								<a class='selflink' href='index.html'>Reference</a>
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								<a class='wikilink' href='http://arduino.cc/en/Main/Hardware'>Hardware</a>
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								<a class='wikilink' href='FAQ.html'>FAQ</a>
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								</p>
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								<p class='vspace'></p>
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								  </div>
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								  <a class="urllink" href="http://www.arduino.cc/blog/" rel="nofollow">Blog »</a> |
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								  <a class="urllink" href="http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl" rel="nofollow">Forum »</a> |
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								  <a class="urllink" href="http://www.arduino.cc/playground/" rel="nofollow">Playground »</a>
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								<div id='wikitext'>
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								<p><strong>Reference</strong>    <a class='selflink' href='index.html'>Language</a> (<a class='wikilink' href='Extended.html'>extended</a>) | <a class='wikilink' href='Libraries.html'>Libraries</a> | <a class='wikilink' href='Comparison.html'>Comparison</a>
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								</p>
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								<p class='vspace'></p><h1>Language Reference</h1>
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								<p><em>See the <strong><a class='wikilink' href='Extended.html'>extended reference</a></strong> for more advanced features of the Arduino languages and the <strong><a class='wikilink' href='Libraries.html'>libraries page</a></strong> for interfacing with particular types of hardware. </em>
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								</p>
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								<p class='vspace'></p><p>Arduino programs can be divided in three main parts: <em>structure</em>, <em>values</em> (variables and constants), and <em>functions</em>.  The Arduino language is based on C/C++.
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								</p>
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								<p class='vspace'></p><p>Here's a <a class='wikilink' href='StyleGuide.html'>style guide</a> that helps with writing examples for beginners.
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								</p>
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								<p class='vspace'></p>
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								<table  width='100%' border='0' cellpadding='5' cellspacing='0'><tr><td  width='50%' valign='top'>
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								<h2>Structure</h2>
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								<ul><li>void <a class='wikilink' href='Setup.html'>setup</a>()
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								</li><li>void <a class='wikilink' href='Loop.html'>loop</a>()
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								</li></ul><p class='vspace'></p><h4>Control Structures</h4>
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								<ul><li><a class='wikilink' href='If.html'>if</a>
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								</li><li><a class='wikilink' href='Else.html'>if...else</a>
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								</li><li><a class='wikilink' href='For.html'>for</a>
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								</li><li><a class='wikilink' href='SwitchCase.html'>switch case</a>
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								</li><li><a class='wikilink' href='While.html'>while</a>
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								</li><li><a class='wikilink' href='DoWhile.html'>do... while</a>
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								</li><li><a class='wikilink' href='Break.html'>break</a>
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								</li><li><a class='wikilink' href='Continue.html'>continue</a>
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								</li><li><a class='wikilink' href='Return.html'>return</a>
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								</li></ul><p class='vspace'></p><h4>Further Syntax</h4>
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								<ul><li><a class='wikilink' href='SemiColon.html'>;</a> (semicolon)
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								</li><li><a class='wikilink' href='Braces.html'>{}</a> (curly braces)
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								</li><li><a class='wikilink' href='Comments.html'>//</a> (single line comment)
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								</li><li><a class='wikilink' href='Comments.html'>/* */</a> (multi-line comment)
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								</li></ul><p class='vspace'></p><h4>Arithmetic Operators</h4>
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								<ul><li><a class='wikilink' href='Assignment.html'>= (assignment)</a>
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								</li><li><a class='wikilink' href='Arithmetic.html'>+ (addition)</a>
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								</li><li><a class='wikilink' href='Arithmetic.html'>-  (subtraction)</a>
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								</li><li><a class='wikilink' href='Arithmetic.html'>* (multiplication)</a>
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								</li><li><a class='wikilink' href='Arithmetic.html'>/ (division)</a>
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								</li><li><a class='wikilink' href='Modulo.html'>% (modulo)</a>
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								</li></ul><p class='vspace'></p><h4>Comparison Operators</h4>
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								<ul><li><a class='wikilink' href='If.html'>==</a> (equal to)
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								</li><li><a class='wikilink' href='If.html'>!=</a> (not equal to)
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								</li><li><a class='wikilink' href='If.html'><</a> (less than)
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								</li><li><a class='wikilink' href='If.html'>></a> (greater than)
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								</li><li><a class='wikilink' href='If.html'><=</a> (less than or equal to)
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								</li><li><a class='wikilink' href='If.html'>>=</a> (greater than or equal to)
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								</li></ul><p class='vspace'></p><h4>Boolean Operators</h4>
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								<ul><li><a class='wikilink' href='Boolean.html'>&&</a> (and)
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								</li><li><a class='wikilink' href='Boolean.html'>||</a> (or)
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								</li><li><a class='wikilink' href='Boolean.html'>!</a> (not)
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								</li></ul><p class='vspace'></p><h4>Compound Operators</h4>
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								<ul><li><a class='wikilink' href='Increment.html'>++</a> (increment)
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								</li><li><a class='wikilink' href='Increment.html'>--</a> (decrement)
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								</li><li><a class='wikilink' href='IncrementCompound.html'>+=</a> (compound addition)
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								</li><li><a class='wikilink' href='IncrementCompound.html'>-=</a> (compound subtraction)
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								</li><li><a class='wikilink' href='IncrementCompound.html'>*=</a> (compound multiplication)
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								</li><li><a class='wikilink' href='IncrementCompound.html'>/=</a> (compound division)
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								</li></ul><p class='vspace'></p><h2>Variables</h2>
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								<p>Variables are expressions that you can use in programs to store values, such as a sensor reading from an analog pin.  
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								</p>
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								<p class='vspace'></p><h4>Constants</h4>
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								<p>Constants are particular values with specific meanings.  
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								</p>
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								<p class='vspace'></p><ul><li><a class='wikilink' href='Constants.html'>HIGH</a> | <a class='wikilink' href='Constants.html'>LOW</a>
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								</li><li><a class='wikilink' href='Constants.html'>INPUT</a> | <a class='wikilink' href='Constants.html'>OUTPUT</a>
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								</li><li><a class='wikilink' href='Constants.html'>true</a> | <a class='wikilink' href='Constants.html'>false</a>
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								<p class='vspace'></p></li><li><a class='wikilink' href='IntegerConstants.html'>Integer Constants</a>
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								</li></ul><p class='vspace'></p><h4>Data Types</h4>
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								<p>Variables can have various types, which are described below.  
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								<p class='vspace'></p><ul><li><a class='wikilink' href='BooleanVariables.html'>boolean</a>
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								</li><li><a class='wikilink' href='Char.html'>char</a>
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								</li><li><a class='wikilink' href='Byte.html'>byte</a>
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								</li><li><a class='wikilink' href='Int.html'>int</a>
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								</li><li><a class='wikilink' href='UnsignedInt.html'>unsigned int</a>
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								</li><li><a class='wikilink' href='Long.html'>long</a>
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								</li><li><a class='wikilink' href='UnsignedLong.html'>unsigned long</a>
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								</li><li><a class='wikilink' href='Float.html'>float</a>
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								</li><li><a class='wikilink' href='Double.html'>double</a>
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								</li><li><a class='wikilink' href='String.html'>string</a>
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								</li><li><a class='wikilink' href='Array.html'>array</a>
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								</li><li><a class='wikilink' href='Void.html'>void</a>
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								</li></ul><p class='vspace'></p><h4>Conversion</h4>
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								<ul><li><a class='wikilink' href='CharCast.html'>char()</a>
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								</li><li><a class='wikilink' href='ByteCast.html'>byte()</a>
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								</li><li><a class='wikilink' href='IntCast.html'>int()</a>
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								</li><li><a class='wikilink' href='LongCast.html'>long()</a>
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								</li><li><a class='wikilink' href='FloatCast.html'>float()</a>
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								</li></ul><p class='vspace'></p><h2>Reference</h2>
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								<ul><li><a class='wikilink' href='ASCIIchart.html'>ASCII chart</a>
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								</li></ul><p class='vspace'></p></td><td  width='50%' valign='top'> 
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								<h2>Functions</h2>
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								<p><strong>Digital I/O</strong>
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								</p><ul><li><a class='wikilink' href='PinMode.html'>pinMode</a>(pin, mode)   
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								</li><li><a class='wikilink' href='DigitalWrite.html'>digitalWrite</a>(pin, value) 
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								</li><li>int <a class='wikilink' href='DigitalRead.html'>digitalRead</a>(pin)
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								</li></ul><p class='vspace'></p><p><strong>Analog I/O</strong>
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								</p><ul><li>int <a class='wikilink' href='AnalogRead.html'>analogRead</a>(pin)
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								</li><li><a class='wikilink' href='AnalogWrite.html'>analogWrite</a>(pin, value) - <em>PWM</em>
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								</li></ul><p class='vspace'></p><p><strong>Advanced I/O</strong>
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								</p><ul><li><a class='wikilink' href='ShiftOut.html'>shiftOut</a>(dataPin, clockPin, bitOrder, value) 
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								</li><li>unsigned long <a class='wikilink' href='PulseIn.html'>pulseIn</a>(pin, value)
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								</li></ul><p class='vspace'></p><p><strong>Time</strong>
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								</p><ul><li>unsigned long <a class='wikilink' href='Millis.html'>millis</a>()   
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								</li><li>unsigned long <a class='wikilink' href='Micros.html'>micros</a>()
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								</li><li><a class='wikilink' href='Delay.html'>delay</a>(ms)  
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								</li><li><a class='wikilink' href='DelayMicroseconds.html'>delayMicroseconds</a>(us)
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								</li></ul><p class='vspace'></p><p><strong>Math</strong>
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								</p><ul><li><a class='wikilink' href='Min.html'>min</a>(x, y)
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								</li><li><a class='wikilink' href='Max.html'>max</a>(x, y)
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								</li><li><a class='wikilink' href='Abs.html'>abs</a>(x)
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								</li><li><a class='wikilink' href='Constrain.html'>constrain</a>(x, a, b)
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								</li><li><a class='wikilink' href='Map.html'>map</a>(value, fromLow, fromHigh, toLow, toHigh)
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								</li><li><a class='wikilink' href='Pow.html'>pow</a>(base, exponent)
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								</li><li><a class='wikilink' href='Sq.html'>sq</a>(x)
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								</li><li><a class='wikilink' href='Sqrt.html'>sqrt</a>(x)
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								</li></ul><p class='vspace'></p><p><strong>Trigonometry</strong> 
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								</p><ul><li><a class='wikilink' href='Sin.html'>sin</a>(rad)
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								</li><li><a class='wikilink' href='Cos.html'>cos</a>(rad)
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								</li><li><a class='wikilink' href='Tan.html'>tan</a>(rad)
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								</li></ul><p class='vspace'></p><p><strong>Random Numbers</strong>
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								</p>
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								<p class='vspace'></p><ul><li><a class='wikilink' href='RandomSeed.html'>randomSeed</a>(seed)
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								</li><li>long <a class='wikilink' href='Random.html'>random</a>(max)
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								</li><li>long <a class='wikilink' href='Random.html'>random</a>(min, max)
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								</li></ul><p class='vspace'></p><p><strong>Communication</strong>
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								</p>
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								<p class='vspace'></p><ul><li><a class='wikilink' href='Serial.html'>Serial</a>
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								</li></ul><p class='vspace'></p><p><br clear='all' />
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								</p>
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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://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?board=swbugs' rel='nofollow'>Forum</a>.</em>
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