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<p class='vspace'></p><h2><span class='wikiword'>SoftwareSerial</span> Library</h2>
<p>The Arduino hardware has built-in support for serial communication on pins 0 and 1 (which also goes to the computer via the USB connection). The native serial support happens via a piece of hardware (built into the chip) called a <a class='urllink' href='http://en.wikipedia.org/wiki/UART' rel='nofollow'>UART</a>. This hardware allows the Atmega chip to receive serial communication even while working on other tasks, as long as there room in the 64 byte serial buffer.
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<p class='vspace'></p><p>The <span class='wikiword'>SoftwareSerial</span> library has been developed to allow serial communication on other digital pins of the Arduino, using software to replicate the functionality (hence the name "<span class='wikiword'>SoftwareSerial</span>").
</p>
<p class='vspace'></p><h4>Limitations</h4>
<p>Because it's not supported by hardware, the library has a few limitations:
</p>
<p class='vspace'></p><ul><li>Only speeds up to 9600 baud work
</li><li>Serial.available() doesn't work
</li><li>Serial.read() will wait until data arrives
</li><li>Only data received while Serial.read() is being called will be received. Data received at other times will be lost, since the chip is not "listening".
</li></ul><p class='vspace'></p><p><span class='wikiword'>SoftwareSerial</span> appears to have some timing issues and/or software issues. Check this forum thread for discussion.
<a class='urllink' href='http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1176181152' rel='nofollow'>Software Serial Discussion</a>. In particular, if you are having problems using <span class='wikiword'>SoftwareSerial</span> with an Atmega168 chip delete <span class='wikiword'>SoftwareSerial</span>.o in your Arduino directory.
</p>
<p class='vspace'></p><h4>Example</h4>
<pre> <a class='wikilink' href='SoftwareSerialExample.html'>SoftwareSerialExample</a>
</pre>
<p class='vspace'></p><h4>Functions</h4>
<ul><li><a class='wikilink' href='SoftwareSerialConstructor.html'>SoftwareSerial</a>()
</li><li><a class='wikilink' href='SoftwareSerialBegin.html'>begin</a>()
</li><li><a class='wikilink' href='SoftwareSerialRead.html'>read</a>()
</li><li><a class='wikilink' href='SoftwareSerialPrint.html'>print</a>()
</li><li><a class='wikilink' href='SoftwareSerialPrintln.html'>println</a>()
</li></ul><p class='vspace'></p><p><a class='wikilink' href='index.html'>Reference Home</a>
</p>
<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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<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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