<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns:MadCap="http://www.madcapsoftware.com/Schemas/MadCap.xsd" MadCap:lastBlockDepth="6" MadCap:lastHeight="94" MadCap:lastWidth="853" MadCap:disableMasterStylesheet="true" MadCap:tocPath="" MadCap:InPreviewMode="false" MadCap:PreloadImages="false" MadCap:RuntimeFileType="Topic" MadCap:TargetType="WebHelp" lang="en-us" xml:lang="en-us" MadCap:PathToHelpSystem="../../../" MadCap:HelpSystemFileName="Default.xml" MadCap:SearchType="Stem">
<head><title>REVERSE Examples</title>
<link href="../../Resources/Stylesheets/BSE_Help.css" rel="stylesheet" />
<script src="../../SkinSupport/MadCapAll.js" type="text/javascript">
</script>
</head>
<body>
<h1>REVERSE Examples</h1>
<div class="ImagePlusCaption">
<div class="Col2">
<p>
<img src="../../graphics/pgm_icon1.gif" border="0" alt="BS1 icon" title="BS1 icon" />
<img src="../../graphics/pgm_icon2.gif" border="0" alt="BS2 icon" title="BS2 icon" />
<img src="../../graphics/pgm_icon2e.gif" border="0" alt="BS2e icon" title="BS2e icon" />
<img src="../../graphics/pgm_icon2sx.gif" border="0" alt="BS2sx icon" title="BS2sx icon" />
<img src="../../graphics/pgm_icon2p.gif" border="0" alt="BS2p icon" title="BS2p icon" />
<img src="../../graphics/pgm_icon2pe.gif" border="0" alt="BS2pe icon" title="BS2pe icon" />
<img src="../../graphics/pgm_icon2px.gif" border="0" alt="BS2px icon" title="BS2px icon" /><span class="code_in_text"> {PBASIC 2.5}</span>
</p>
</div>
<p style="text-align: right;">Example</p>
<p> </p>
</div>
<p class="clear"> </p>
<p> </p>
<p class="PlainText">Connect an LED and two resistors as shown below for the demo program.</p>
<p class="PlainText" style="text-align: center;">
<img src="../../graphics/reverse_sch.gif" />
</p><pre class="BScode" xml:space="preserve">' REVERSE.BS1
' Connect the circuit shown in the REVERSE command description to I/O pin
' 0 and run this program. The LED will alternate between two states, dim
' and bright. The BASIC Stamp is using the REVERSE command to toggling I/O
' pin 0 between input and output states. When pin 0 is an input, current
' flows through R1, through the LED, through R2 to ground. Pin 0 is
' effectively disconnected and doesn't play a part in the circuit. The total
' resistance encountered by current flowing through the LED is R1 + R2 = 1220
' ohms. When pin 0 is reversed to an output, current flows through R1, through
' the LED, and into pin 0 to ground (because of the 0 written to PIN0). The
' total resistance encountered by current flowing through the LED is R1,
' 220 ohms. With only 20% of the resistance, the LED glows brighter.
' {$STAMP BS1}
' {$PBASIC 1.0}
Setup:
PIN0 = 0 ' Put a low in the pin 0
' output driver
Main:
PAUSE 250 ' 1/4th second pause
REVERSE 0 ' reverse pin 0 I/O direction
GOTO Main ' do forever
</pre>
<p>NOTE: The example below is written for the BS2 and will run on any of the BS2-family modules. Modify the $STAMP directive (as required) before downloading to the BS2e, BS2sx, BS2p, BS2pe, or BS2px.</p><pre class="BScode" xml:space="preserve"> REVERSE.BS2
' Connect the circuit shown in the REVERSE command description to I/O pin
' 0 and run this program. The LED will alternate between two states, dim
' and bright. The BASIC Stamp is using the REVERSE command to toggling I/O
' pin 0 between input and output states. When pin 0 is an input, current
' flows through R1, through the LED, through R2 to ground. Pin 0 is
' effectively disconnected and doesn't play a part in the circuit. The total
' resistance encountered by current flowing through the LED is R1 + R2 = 1220
' ohms. When pin 0 is reversed to an output, current flows through R1, through
' the LED, and into pin 0 to ground (because of the 0 written to OUT0). The
' total resistance encountered by current flowing through the LED is R1,
' 220 ohms. With only 20% of the resistance, the LED glows brighter.
' {$STAMP BS2}
' {$PBASIC 2.5}
Setup:
OUT0 = 0 ' Put a low in the pin 0
' output driver
Main:
PAUSE 250 ' 1/4th second pause
REVERSE 0 ' reverse pin 0 I/O direction
GOTO Main ' do forever
</pre>
<div class="Col2">
<div class="MasterFoot">
<p MadCap:conditions="BSEconditions.BSEWebHelp (Primary)-INCLUDE"><a href="../../HomeTopics/HomePage.htm">Go to Welcome page</a>
</p>
</div>
</div>
<div class="Col2">
<div class="MasterFoot">
<p style="text-align: right;"><span class="ContactInfoProjectName">BASIC Stamp Help</span> <![CDATA[ ]]><span class="ContactInfoVersion#">Version 2.5.4</span> <![CDATA[ ]]></p>
<p style="text-align: right;">Copyright © <span class="ContactInfoCompanyName">Parallax Inc.</span></p>
<p style="text-align: right;"><span class="SystemShortDate">8/8/2012</span>
</p>
</div>
</div>
<script type="text/javascript">/* <![CDATA[ */
var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'UA-285614-1']);
_gaq.push(['_trackPageview']);
(function() {
var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
})();
/* ]]> */</script>
<script type="text/javascript" src="../../SkinSupport/MadCapBodyEnd.js">
</script>
</body>
</html>