path: root/nuttx/Documentation/NuttX.html



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<title>NuttX</title>
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    <td>
      <h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
      <p>Last Updated: August 1, 2011</p>
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    <td>
  <h1>Table of Contents</h1>
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<center><table width ="80%">
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<td>
<table>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#overview">Overview</a>.<br>
    What is NuttX?  Look at all those files and features... How can it be a tiny OS?
  </td>
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<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#group">NuttX Discussion Group</a>.<br>
    Do you want to talk about NuttX features?  Do you need some help?  Problems?  Bugs?
  </td>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#downloads">Downloads</a>.<br>
    Where can I get NuttX?  What is the current development status?
  </td>
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<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#platforms">Supported Platforms</a>.<br>
    What target platforms has NuttX been ported to?
  </td>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#environments">Development Environments</a>.<br>
    What kinds of host cross-development platforms can be used with NuttX?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#footprint">Memory Footprint</a>.<br>
    Just how big is it?  Do I have enough memory to use NuttX?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#licensing">Licensing</a>.<br>
    Are there any licensing restrictions for the use of NuttX? (Almost none)
    Will there be problems if I link my proprietary code with NuttX? (No)
  </td>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#history">Release History</a><br>
    What has changed in the last release of NuttX?
    What unreleased changes are pending in SVN?
  </td>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#TODO">Bugs, Issues, <i>Things-To-Do</i></a>.<br>
    Software is never finished nor ever tested well enough.
    (Do you want to help develop NuttX?  If so, send me an email).
  </td>
</tr>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#documentation">Other Documentation</a>.<br>
    What other NuttX documentation is available?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#trademarks">Trademarks</a>.<br>
    Some of the words used in this document belong to other people.
  </td>
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</table>
</td>
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</table></center>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="overview"><h1>Overview</h1></a>
  </td>
  </tr>
</table>

<p>
  <b>Goals</b>.
  Nuttx is a real timed embedded operating system (RTOS).
  Its goals are:
<p>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Small Footprint</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Usable in all but the tightest micro-controller environments,
      The focus is on the tiny-to-small, deeply embedded environment.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Rich Feature OS Set</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      The goal is to provide implementations of most standard POSIX OS interfaces
      to support a rich, multi-threaded development environment for deeply embedded
      processors.
    </p>
      NON-GOALS: (1) It is not a goal to provide the rich level of OS
      features like those provided with Linux.
      Small footprint is more important than features.
      Standard compliance is more important than small footprint.
      (2) There is no MMU-based support for processes.
      At present, NuttX assumes a flat address space.
    </p>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Highly Scalable</b>
  </td>
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<tr>
  <td><br></td>
  <td>
    <p>
      Fully scalable from tiny (8-bit) to moderate embedded (32-bit).
      Scalability with rich feature set is accomplished with:
      Many tiny source files, link from static libraries, highly configurable, use of
      weak symbols when available.
    </p>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Standards Compliance</b>
  </td>
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<tr>
  <td><br></td>
  <td>
    <p>
      NuttX strives to achieve a high degree of standards compliance.
      The primary governing standards are POSIX and ANSI standards.
      Additional standard APIs from Unix and other common RTOS's are
      adopted for functionality not available under these standards
      or for functionality that is not appropriate for the deeply-embedded
      RTOS (such as <code>fork()</code>).
    </p>
    <p>
      Because of this standards conformance, software developed under other
      standard OSs (such as Linux) should port easily to NuttX.
    </p>
</tr>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Real-Time</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Fully pre-emptible, fixed priority and round-robin scheduling.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Totally Open</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Non-restrictive BSD license.
    </p>
</tr>
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  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>GNU Toolchains</b>
  </td>
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<tr>
  <td><br></td>
  <td>
    <p>
      Compatible GNU toolchains based on <a href="http://buildroot.uclibc.org/">buildroot</a>
      available for
      <a href="https://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">download</a>
      to provide a complete development environment for many architectures.
    </p>
</tr>
</table></center>

<p>
  <b>Feature Set</b>.
  Key features of NuttX include:
<p>
<center><table width="90%">

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Standards Compliant Core Task Management</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Modular, micro-kernel</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Fully pre-emptible.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Naturally scalable.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Highly configurable.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Easily extensible to new processor architectures, SoC architecture, or board architectures.
          A <a href="NuttxPortingGuide.html">Porting Guide</a> is in development.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>FIFO and round-robin scheduling.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Realtime, deterministic, with support for priority inheritance</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>POSIX/ANSI-like task controls, named message queues, counting semaphores, clocks/timers, signals, pthreads, environment variables, filesystem.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>VxWorks-like task management and watchdog timers.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>BSD socket interface.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Extensions to manage pre-emption.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>On-demand paging.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>May be built either as an open, flat embedded RTOS or as a separtely built, secure micro-kernel with a system call interface.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Well documented in the NuttX <a href="NuttxUserGuide.html">User Guide</a>.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>File system</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Tiny in-memory, root pseudo-file-system.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Supports character and block drivers.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Network, USB (host), USB (device), serial, CAN, driver architectures.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>RAMDISK, pipes, FIFO, <code>/dev/null</code>, <code>/dev/zero</code> drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Mount-able volumes.  Bind mountpoint, filesystem, and block device driver.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>FAT12/16/32 filesystem support with optional FAT long file name support<small><sup>1</sup></small>.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>NXFFS. the NuttX wear-leveling FLASH file system.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Generic driver for SPI-based MMC/SD/SDH cards.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>ROMFS filesystem support.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><a href="NuttXNxFlat.html">NXFLAT</a>.
      A new binary format call NXFLAT that can be used to 
      execute separately linked programs in place in a file system.
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p><small>
      <sup>1</sup>
      FAT long file name support may be subject to certain Microsoft patent restrictions if enabled.
      See the top-level <code>COPYING</code> file for details.
    </small></p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>C Library</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Fully integrated into the OS.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Networking</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>TCP/IP, UDP, ICMP, IGMPv2 (client) stacks.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>SLIP</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Small footprint (based on uIP).</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>BSD compatible socket layer.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Networking utilities (DHCP server and client, SMTP client, TELNET client, FTP client, TFTP client, HTTP server and client)</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>
        A NuttX port of Jeff Poskanzer's <a href="http://acme.com/software/thttpd">THTTPD</a> HTTP server
        integrated with <a href="NuttXNxFlat.html">NXFLAT</a> to provide true, embedded CGI.
      </li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>FLASH Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><i>MTD</i>-inspired interface for <i>M</i>emory <i>T</i>echnology <i>D</i>evices.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><i>FTL</i>.  Simple <i>F</i>lash <i>T</i>ranslation <i>L</i>ayer support file systems on FLASH.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>NXFFS. the NuttX wear-leveling FLASH file system.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Support for SPI-based FLASH and FRAM devices.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>USB Host Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>USB host architecture for USB host controller drivers and device-dependent USB class drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>USB host controller drivers available for the NXP LPC17xx.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Device-dependent USB class drivers available for USB mass storage and HID keyboard.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>USB Device Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><i>Gadget</i>-like architecture for USB device controller drivers and device-dependent USB class drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>USB device controller drivers available for the NXP LPC17xx, LPC214x, LPC313x, STMicro STM32 and TI DM320.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Device-dependent USB class drivers available for USB serial and for USB mass storage.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Built-in <a href="UsbTrace.html">USB trace</a> functionality for USB debug.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Graphics Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Framebuffer drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>LCD drivers for both parallel and SPI LCDs and OLEDs.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>
         NX: A graphics library, tiny windowing system and tiny font support that works with either framebuffer or LCD drivers.
         Documented in the <a href="NXGraphicsSubsystem.html">NX Graphics Subsystem</a>
         manual.
      </li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Font management sub-system.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Input Devices</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Touchscreen, USB keyboard, GPIO-based buttons and keypads. </li>
    </p>
</tr>
</table></center>

<p>
  <b>NuttX Add-Ons</b>.
  The following packages are available to extend the basic NuttX feature set:
</p>
<center><table width="90%">

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>NuttShell (NSH)</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>A small, scalable, bash-like shell for NuttX with rich feature set and small footprint.
        See the <a href="NuttShell.html">NuttShell User Guide</a>.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Pascal Compiler with NuttX runtime P-Code interpreter add-on</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>The Pascal add-on is available for download from the
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573">SourceForge</a>
        website.</li>
    </p>
  </td>
</tr>
</table></center>

<p>
  <b>Look at all those files and features... How can it be a tiny OS?</b>.
  The NuttX feature list (above) is fairly long and if you look at the NuttX
  source tree, you will see that there are hundreds of source files comprising
  NuttX.  How can NuttX be a tiny OS with all of that?
</p>
<center><table width="90%">

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Lots of Features -- More can be smaller!</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      The philosophy behind that NuttX is that lots of features are great... <i>BUT</i>
      also that if you don't use those features, then you should not have to pay a penalty
      for the unused features.
      And, with NuttX, you don't!  If you don't use a feature, it will not
      be included in the final executable binary.
      You only have to pay the penalty of increased footprint for the features
      that you actually use.
    </p>
    <p>
      Using a variety of technologies, NuttX can scale from the very tiny to
      the moderate-size system.  I have executed NuttX with some simple applications
      in as little as 32Kb <i>total</i> memory (code and data).
      On the other hand, typical, richly featured NuttX builds require more like 64Kb
      (and if all of the features are used, this can push 100Kb).
    </p>
  </td>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Many, many files -- More really is smaller!</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      One may be intimidated by the size NuttX source tree.  There are hundreds of source files!
      How can that be a tiny OS?
      Actually, the large number of files is one of the tricks to keep NuttX small and
      as scalable as possible.
      Most files contain only a single function. 
      Sometimes just one tiny function with only a few lines of code.
      Why?
    </p>
    <ul>
      <li>
        <b>Static Libraries</b>.
        Because in the NuttX build processed, objects are compiled and saved into
        <i>static libraries</i> (<i>archives</i>).
        Then, when the file executable is linked, only the object files that are needed
        are extracted from the archive and added to the final executable.
        By having many, many tiny source files, you can assure that no code that you do
        not execute is ever included in the link.
        And by having many, tiny source files you have better granularity --
        if you don't use that tiny function of even just a few lines of code, it will
        not be included in the binary.
      </li>
    </ul>
  </td>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Other Tricks</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      As mentioned above, the use of many, tiny source files and linking from static
      libraries keeps the size of NuttX down.
      Other tricks used in NuttX include:
    </p>
    <ul>
      <li>
         <b>Configuration Files</b>.
         Before you build NuttX, you must provide a configuration file that specifies
         what features you plan to use and which features you do not.
         This configuration file contains a long list of settings that control
         what is built into NuttX and what is not.
         There are hundreds of such settings
         (see the <a href="NuttxPortingGuide.html#apndxconfigs">NuttX Porting Guide</a>
         for a partial list that excludes platform specific settings).
         These many, many configuration options allow NuttX to be highly tuned to
         meet size requirements.
         The downside to all of these configuration options is that it greatly
         complicates the maintenance of NuttX -- but that is my problem, not yours.
      </li>
      <li>
         <b>Weak Symbols</b>
         The GNU toolchain supports <i>weak</i> symbols and these also help to keep
         the size of NuttX down.
         Weak symbols prevent object files from being drawn into the link even if they
         are accessed from source code.
         Careful use of weak symbols is another trick for keep unused code out of the
         final binary.
      </li>
    </ul>
  </td>
</tr>

</table></center>


<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="group"><h1>NuttX Discussion Group</h1></a>
  </td>
  </tr>
</table>

<p>
  Most Nuttx-related discussion occurs on the <a href="http://tech.groups.yahoo.com/group/nuttx/" target="_top"><i>Yahoo!</i> NuttX group</a>.
  You are cordially invited to <a href="http://groups.yahoo.com/group/nuttx/join" target="_top">join</a>.
  I make a special effort to answer any questions and provide any help that I can.
</p>


<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="downloads"><h1>Downloads</h1></a>
  </td>
  </tr>
</table>

<p><b>nuttx-6.7 Release Notes</b>:
<p>
  The 74<sup>th</sup> release of NuttX, Version 6.7, was made on  August 2, 2011, 2011 and is available for download from the
  <a href="http://sourceforge.net/projects/nuttx/files/">SourceForge</a> website.
  Note that release consists of two tarballs:  <code>nuttx-6.7.tar.gz</code> and <code>apps-6.7.tar.gz</code>.
  Both may be needed (see the top-level <code>nuttx/README.txt</code> file for build information)
  The change log associated with the release is available <a href="#currentrelease">here</a>.
  Unreleased changes after this release are available in SVN.
  These unreleased changes are also listed <a href="#pendingchanges">here</a>.
</p>
<p>
  Changes in this release are summarized below:
</p>
<ul>
  <li>
    <b>New OS APIs</b>:
      Add the standard <code>sem_timedwait()</code> interface.
  </li>
  <li>
    <b>FAT File System</b>:
      Adds (optional) support for VFAT long file names.
  </li>
  <li>
    <b>USB</b>:
      Now the mass storage device can be connected when needed and
      disconnected when not needed (or re-connected as a different kind of
      device).
  </li>
  <li>
    <b>Touchscreen Support</b>:
      Defined a new NuttX touchscreen interface.
      Added a driver for the TI TSC2007 touchscreen controller chip.
  </li>
  <li>
    <b>NX Fonts</b>:
      Add support for multiple fonts; developed a tool to
      convert open source fonts into NuttX format; Converted and installed
      nine new, high quality fontsets.
  </li>
  <li>
    <b>NX Graphics</b>:
      Add new NX APIs to support drawing of wide lines in any
      orientation.  Added new low level routines to set individual pixel
      more efficiently.
  </li>
  <li>
    <b>Build system</b>:
      Added a export target that will bundle up all of the
      NuttX libraries, header files, and the startup object into an export-able tarball.
  </li>
  <li>
    <b>LPC17xx</b>:
      A CAN driver was contributed by Li Zhuoyi (Lzyy).
  </li>
  <li>
    <b>STM32</b>:
      New NX-related configurations to excercise text and graphic image displays.
  </li>
  <li>
    <b>C Library</b>:
      Added a fixed precision atan2() math function.
  </li>
  <li>
    <b>Bugfixes</b>:
      Serial RX overrun error, FAT upper/lower NT 8.3 name
      handling fixed.  FAT directory allocation and initialization bug.
      STM32 SDIO DMA race condition bug.  eZ80 UART1 serial driver errors
      (Paul Osmialowski)
  </li>
</ul>
<p>
  See the <a href="#currentrelease">ChangeLog</a> for details.
</p>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="platforms"><h1>Supported Platforms</h1></a>
  </td>
  </tr>
</table>

<p>The short story (Number of ports follow in parentheses. Follow the links for the details):</p>
<center><table width="90%">
<ul>
  <tr>
  <td bgcolor="#e4e4e4" valign="top">
  <li><a href="#linuxusermode">Linux user mode simulation</a> (1)</li>
  <li>ARM
    <ul>
      <li><a href="#arm7tdmi">ARM7TDMI</b></a> (4)</li>
      <li><a href="#arm920t">ARM920T</a> (1) </li>
      <li><a href="#arm926ejs">ARM926EJS</a> (3) </li>
      <li><a href="#armcortexm3">ARM Cortex-M3</a> (10)</li>
    </ul>
  <li>Atmel AVR
    <ul>
      <li><a href="#atmelavr">Atmel 8-bit AVR</a> (3) </li>
      <li><a href="#atmelavr32">Atmel AVR32</a> (1) </li>
    </ul>
  </li>
  </td>
  <td bgcolor="#e4e4e4" valign="top">
  <li>Freescale <a href="#m68hcs12">M68HCS12</a> (2) </li>
  <li>Intel
    <ul>
      <li><a href="#8052">Intel 8052 Microcontroller</a> (1)</li>
      <li><a href="#80x86">Intel 80x86</a> (2)</li>
    </ul>
  </li>
  <li>MicroChip <a href="#pic32mips">PIC32</a> (MIPS) (2)</li>
  <li>Renesas/Hitachi:
    <ul>
        <li><a href="#superh">Renesas/Hitachi SuperH</a> (1/2)</li>
        <li><a href="#m16c">Renesas M16C/26</a> (1/2)</li>
    </ul>
  </li>
  </td>
  <td bgcolor="#e4e4e4" valign="top">
  <li>Zilog
    <ul>
        <li><a href="#zilogz16f">Zilog Z16F</a> (1)</li>
        <li><a href="#zilogez80acclaim">Zilog eZ80 Acclaim!</a> (1)</li>
        <li><a href="#zilogz8encore">Zilog Z8Encore!</a> (2)</li>
        <li><a href="#zilogz80">Zilog Z80</a> (2)</li>
    </ul>
  </li>
</ul>
  </tr>
</table></center>

<p>The details, caveats and fine print follow:</p>

<center><table width="90%">
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="linuxusermode"><b>Linux User Mode</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      A user-mode port of NuttX to the x86 Linux/Cygwin platform is available.
      The purpose of this port is primarily to support OS feature development.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Does not support interrupts but is otherwise fully functional.
      </p>
    </ul>
   </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="arm7tdmi"><b>ARM7TDMI</b></a>.
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>TI TMS320C5471</b> (also called <b>C5471</b> or <b>TMS320DA180</b> or <b>DA180</b>).
      NuttX operates on the ARM7 of this dual core processor.
      This port uses the <a href="http://www.spectrumdigital.com/">Spectrum Digital</a>
      evaluation board with a GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        This port is complete, verified, and included in the initial NuttX release.
      </p>
    </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>NXP LPC214x</b>.
      Support is provided for the NXP LPC214x family of processors.  In particular,
      support is provided for the mcu123.com lpc214x evaluation board (LPC2148).
      This port also used the GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        This port boots and passes the OS test (apps/examples/ostest).
        The port is complete and verified.  As of NuttX 0.3.17, the port includes:
        timer interrupts, serial console, USB driver, and SPI-based MMC/SD card
        support.  A verified NuttShell (<a href="NuttShell.html">NSH</a>)
        configuration is also available.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>NXP LPC2378</b>.
      Support is provided for the NXP LPC2378 MCU.  In particular,
      support is provided for the Olimex-LPC2378 development board.
      This port was contributed by Rommel Marcelo is was first released in NuttX-5.3.
      This port also used the GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        This port boots and passes the OS test (apps/examples/ostest) and includes a
        working implementation of the NuttShell (<a href="NuttShell.html">NSH</a>).
        The port is complete and verified.
        As of NuttX 5.3, the port includes only basic timer interrupts and serial console support.
      </p>
      <p>
        <b>Development Environments:</b> (Same as for the NXP LPC214x).
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>STMicro STR71x</b>.
      Support is provided for the STMicro STR71x family of processors.  In particular,
      support is provided for the Olimex STR-P711 evaluation board.
      This port also used the GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Integration is complete on the basic port (boot logic, system time, serial console).
        Two configurations have been verified: (1) The board boots and passes the OS test
        with console output visible on UART0, and the NuttShell (<a href="NuttShell.html">NSH</a>)
        is fully functional with interrupt driven serial console.  An SPI driver is available
        but only partially tested.  Additional features are needed: USB driver, MMC integration,
        to name two (the slot on the board appears to accept on MMC card dimensions; I have only
        SD cards).
        An SPI-based ENC29J60 Ethernet driver for add-on hardware is under development and
        should be available in the NuttX 5.5 release.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="arm920t"><b>ARM920T</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Freescale MC9328MX1</b> or <b>i.MX1</b>.
      This port uses the Freescale MX1ADS development board with a GNU arm-elf toolchain*
      under either Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          This port has stalled due to development tool issues.
          Coding is complete on the basic port (timer, serial console, SPI).
      </p>
    </ul>
   </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="arm926ejs"><b>ARM926EJS</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>TI TMS320DM320</b> (also called <b>DM320</b>).
      NuttX operates on the ARM9 of this dual core processor.
      This port uses the
      <a href="http://wiki.neurostechnology.com/index.php/Developer_Welcome">Neuros OSD</a>
      with a GNU arm-elf toolchain* under Linux or Cygwin.
      The port was performed using the OSD v1.0, development board.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The basic port (timer interrupts, serial ports, network, framebuffer, etc.) is complete.
          All implemented features have been verified with the exception of the USB device-side
          driver; that implementation is complete but untested.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <b>NXP <a href="http://ics.nxp.com/products/lpc3000/lpc313x.lpc314x.lpc315x/">LPC3131</a></b>.
    The port for the NXP LPC3131 on the <a href="http://www.embeddedartists.com/products/kits/lpc3131_kit.php">Embedded Artists EA3131</a> 
    development board was first released in NuttX-5.1 with a GNU arm-elf or arm-eabi toolchain* under Linux or Cygwin
    (but was not functional until NuttX-5.2).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The basic EA3131 port is complete and verified in NuttX-5.2 
          This basic port includes basic boot-up, serial console, and timer interrupts.
          This port was extended in NuttX 5.3 with a USB high speed driver contributed by David Hewson.
          David also contributed I2C and SPI drivers plus several important LPC313x USB bug fixes
          that appear in the NuttX 5.6 release.
          This port has been verified using the NuttX OS test, USB serial and mass storage
          tests and includes a working implementation of the NuttShell (<a href="NuttShell.html">NSH</a>).
      </p>
      <p>
          Support for <a href="NuttXDemandPaging.html">on-demand paging</a> has been developed for the EA3131.
      That support would all execute of a program in SPI FLASH by paging code sections out of SPI flash as needed.
      However, as of this writing, I have not had the opportunity to verify this new feature.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <b>NXP LPC315x</b>.
    Support for the NXP LPC315x family has been incorporated into the code base as of NuttX-6.4.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The MCU support logic is present but as of this writing has not been verified on hardware.
          Because of the high degree of compatibility between the LPC313x and LPC315x family, it
          is very likely that the support is in place (or at least very close).
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="armcortexm3"><b>ARM Cortex-M3</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S6918</b>.
      This port uses the <a href=" http://www.micromint.com/">Micromint</a> Eagle-100 development
      board with a GNU arm-elf toolchain* under either Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The initial, release of this port was included in NuttX  version 0.4.6.
          The current port includes timer, serial console, Ethernet, SSI, and microSD support.
          There are working configurations the NuttX OS test, to run the <a href="NuttShell.html">NuttShell
          (NSH)</a>, the NuttX networking test, and the uIP web server.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S6965</b>.
      This port uses the Stellaris LM3S6965 Ethernet Evalution Kit with a GNU arm-elf toolchain*
      under either Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          This port was released in NuttX 5.5.  
          Features are the same as with the Eagle-100 LM3S6918 described above.
          The apps/examples/ostest configuration has been successfully verified and an
          NSH configuration with telnet support is available.
          MMC/SD and Networking support was not been thoroughly verified:
          Current development efforts are focused on porting the NuttX window system (NX)
          to work with the Evaluation Kits OLED display.
      </p>
      <p><small>
         <b>NOTE</b>: As it is configured now, you MUST have a network connected.
         Otherwise, the NSH prompt will not come up because the Ethernet
         driver is waiting for the network to come up.
      </small></p>
      <p>
        <b>Development Environments:</b> See the Eagle-100 LM3S6918 above.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S8962</b>.
      This port uses the Stellaris EKC-LM3S8962 Ethernet+CAN Evalution Kit with a GNU arm-elf toolchain*
      under either Linux or Cygwin.
      Contributed by Larry Arnold.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          This port was released in NuttX 5.10. 
          Features are the same as with the Eagle-100 LM3S6918 described above.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S9B96</b>.
      Header file support was contributed by Tiago Maluta for this part.
      However, no complete board support configuration is available as of this writing.
    </p>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>STMicro STM32F103x</b>.
      Support for three MCUs and two board configurations are available.
      MCU support includes: STM32F103ZET6, STM32F103RET6, and STM32F107VC.
      Board support includes:
    </p>
    <ol>
      <li>
        This port uses the <a href=" http://www.st.com/">STMicro</a> STM3210E-EVAL development board that
        features the STM32F103ZET6 MCU.
      </li>
      <li>
        ISOTEL NetClamps VSN V1.2 ready2go sensor network platform based on the
        STMicro STM32F103RET6.  Contributed by Uros Platise.
      </li>
    </ol>
    <p>
      These ports uses a GNU arm-elf toolchain* under either Linux or Cygwin (with native Windows GNU
      tools or Cygwin-based GNU tools).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
      </p>
      <ul>
        <li>
          The basic STM32 port was released in NuttX version 0.4.12. The basic port includes boot-up
          logic, interrupt driven serial console, and system timer interrupts.
          The 0.4.13 release added support for SPI, serial FLASH, and USB device.;
          The 4.14 release added support for buttons and SDIO-based MMC/SD and verifed DMA support.
          Verified configurations are available for NuttX OS test, the NuttShell (NSH) example,
          the USB serial device class, and the USB mass storage device class example.
        </li>
        <li>
          Support for the NetClamps VSN was included in version 5.18 of NuttX.
        </li>
      </ul>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (RIDE7, CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Atmel AT91SAM3U</b>.
      This port uses the <a href="http://www.atmel.com/">Atmel</a> SAM3U-EK
      development board that features the AT91SAM3U4E MCU.
      This port uses a GNU arm-elf or arm-eabi toolchain* under either Linux or Cygwin (with native Windows GNU
      tools or Cygwin-based GNU tools).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        The basic SAM3U-EK port was released in NuttX version 5.1. The basic port includes boot-up
        logic, interrupt driven serial console, and system timer interrupts.
        That release passes the NuttX OS test and is proven to have a valid OS implementation.
        A configuration to support the NuttShell is also included.
        NuttX version 5.4 adds support for the HX8347 LCD on the SAM3U-EK board.
        This LCD support includes an example using the
        <a href=" http://www.nuttx.org/NXGraphicsSubsystem.html">NX graphics system</a>.
      </p>
      <p>
        Subsequent NuttX releases will extend this port and add support for SDIO-based SD cards and
        USB device (and possible LCD support).
        These extensions may or may not happen by the Nuttx 5.5 release as my plate is kind of full now.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a>
        package.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>NXP LPC1766 and LPC1768</b>.
      Configurations are available for three boards:
      <ul>
        <li>
          The Nucleus 2G board from <a href="http://www.2g-eng.com/">2G Engineering</a> (LPC1768),
        </li>
        <li>
          The mbed board from <a href="http://mbed.org">mbed.org</a> (LPC1768, Contributed by Dave Marples), and
        </li>
        <li>
          The LPC1766-sTK board from <a href="http://www.olimex.com/">Olimex</a> (LPC1766).
        </li>
        <li>
          The Embedded Artists base board with NXP LPCXpresso LPC1768.
        </li>
      </ul>
    </p>
    <p>
      The Nucleus 2G boar, the mbed board, and the LPCXpresso all feature the NXP LPC1768 MCU;
      the Olimex LPC1766-STK board features an LPC1766.
      All use a GNU arm-elf or arm-eabi toolchain* under either Linux or Cygwin (with native Windows GNU tools or Cygwin-based GNU tools).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        The following summarizes the features that has been developed and verified on individual LPC17xx-based boards.
        These features should, however, be common and available for all LPC17xx-based boards.
      </p>
      <ol>
        <li>
        <p><b>Nucleus2G LPC1768</b></p>
        <ul>
          <li>
            Some initial files for the LPC17xx family were released in NuttX 5.6, but
          </li>
          <li>
            The first functional release for the NXP LPC1768/Nucleus2G occured with NuttX 5.7 with
            Some additional enhancements through NuttX-5.9.
          </li>
        </ul>
      </p>
      <p>
        That initial, 5.6, basic release included <i>timer</i> interrupts and a <i>serial console</i> and was
        verified using the NuttX OS test (<code>apps/examples/ostest</code>).
        Configurations available include include a verified NuttShell (NSH) configuration
        (see the <a href="http://www.nuttx.org/NuttShell.html">NSH User Guide</a>).
        The NSH configuration supports the Nucleus2G's microSD slot and additional configurations
        are available to exercise the the USB serial and USB mass storage devices.
        However, due to some technical reasons, neither the SPI nor the USB device drivers are fully verified.
        (Although they have since been verfiied on other platforms; this needs to be revisited on the Nucleus2G).
      </p>
      </li>
      <li>
        <p><b>mbed LPC1768</b></p>
        <ul>
          <li>
            Support for the mbed board was contributed by Dave Marples and released in NuttX-5.11.
          </li>
        </ul>
      </p>
      <p>
        This port includes a NuttX OS test configuration (see <code>apps/examples/ostest</code>).
      </p>
      </li>
      <li>
        <p><b>Olimex LPC1766-STK</b></p>
        <ul>
          <li>
            Support for that Olimex-LPC1766-STK board was added to NuttX 5.13.
          </li>
          <li>
            The NuttX-5.14 release extended that support with an <i>Ethernet driver</i>.
          </li>
          <li>
            The NuttX-5.15 release further extended the support with a functional <i>USB device driver</i> and <i>SPI-based micro-SD</i>.
          </li>
          <li>
            The NuttX-5.16 release added a functional <i>USB host controller driver</i> and <i>USB host mass storage class driver</i>.
          </li>
          <li>
            The NuttX-5.17 released added support for low-speed USB devicers, interrupt endpoints, and a <i>USB host HID keyboard class driver</i>.
          </li>
        </ul>
      </p>
      <ul><p>
        Verified configurations are now available for the NuttX OS test,
        for the NuttShell with networking and microSD support(NSH, see the <a href="ttp://www.nuttx.org/NuttShell.html">NSH User Guide</a>),
        for the NuttX network test, for the <a href="http://acme.com/software/thttpd">THTTPD</a> webserver,
        for USB serial deive and USB storage devices examples, and for the USB host HID keyboard driver.
        Support for the USB host mass storage device can optionally be configured for the NSH example.
        A driver for the <i>Nokia 6100 LCD</i> and an NX graphics configuration for the Olimex LPC1766-STK have been added.
        However, neither the LCD driver nor the NX configuration have been verified as of the the NuttX-5.17 release.
      </p></ul>
      </li>
      <li>
        <p><b>Embedded Artists base board with NXP LPCXpresso LPC1768</b></p>
        <ul>
           An fully verified board configuration is included in NuttX-6.2.
           The Code Red toolchain is supported under either Linux or Windows.
           Verifed configurations include DHCPD, the NuttShell (NSH), NuttX graphis (NX), the NuttX OS test, THTTPD, and USB mass storage device.
        </ul>
      </li>
      </ol>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery devkitARM or Code Red).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a>
        package.
      </p>
   </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="atmelavr"><b>Atmel AVR</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>SoC Robotics ATMega128</b>.
      This port of NuttX to the Amber Web Server from <a href="http://www.soc-robotics.com/index.htm">SoC Robotics</a>
      is partially completed.
      The Amber Web Server is based on an Atmel ATMega128.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         Work on this port has stalled due to toolchain issues.  Complete, but untested
         code for this port appears in the NuttX 6.5 release.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Micropendous 3 AT9USB64x</b> and <b>AT9USB6128x</b>.
      This port of NuttX to the Opendous Micropendous 3 board. The Micropendous3 is
      may be populated with an AT90USB646, 647, 1286, or 1287.  I have only the AT90USB647
      version for testing.  This version have very limited memory resources: 64Kb of
      FLASH and 4Kb of SRAM.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         The basic port was released in NuttX-6.5.  This basic port consists only of
         a &quot;Hello, World!!&quot; example that demonstrates initialization of the OS,
         creation of a simple task, and serial console output.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PJRC Teensy++ 2.0 AT9USB1286</b>.
      This is a port of NuttX to the PJRC Teensy++ 2.0 board.
      This board was developed by <a href="http://pjrc.com/teensy/">PJRC</a>.
      The Teensy++ 2.0 is based on an Atmel AT90USB1286 MCU.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         The basic port was released in NuttX-6.5.  This basic port consists of
         a &quot;Hello, World!!&quot; example that demonstrates initialization of the OS,
         creation of a simple task, and serial console output as well as a somewhat
         simplified NuttShell (NSH) configuration (see the
         <a href="http://www.nuttx.org/NuttShell.html">NSH User Guide</a>).
      </p>
      <p>
         An SPI driver and a USB device driver exist for the AT90USB as well
         as a USB mass storage configureation.  However, this configuration is not
         fully debugged as of the NuttX-6.5 release.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p><b>AVR-Specific Issues</b>.
      The basic AVR port is solid and biggest issue for using AVR is its tiny SRAM memory and its Harvard architecture.
      Because of the Harvard architecture, constant data that resides to flash is inaccessible using &quot;normal&quot; memory reads and writes (only SRAM data can be accessed &quot;normally&quot;).
      Special AVR instructions are available for accessing data in FLASH, but these have not been integrated into the normal, general purpose OS.
    </p>
    <p>
      Most NuttX test applications are console-oriented with lots of strings used for printf and debug output.
      These strings are all stored in SRAM now due to these data accessing issues and even the smallest console-oriented applications can quickly fill a 4-8Kb memory.
      So, in order for the AVR port to be useful, one of two things would need to be done:
    </p>
    <ol>
      <li>
        Don't use console applications that required lots of strings.
        The basic AVR port is solid and your typical deeply embedded application should work fine.
        Or,
      </li>
      <li>
        Create a special version of printf that knows how to access strings that reside in FLASH (or EEPROM).
      </li>
    </ol>
</tr>
<tr>
  <td><br></td>
  <td>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin with Windows native toolchain. 
        All testing, however, has been performed using the Nuttx DIY toolchain for Linux  or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a> package.
        As a result, that toolchain is recommended.
      </p>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><br></td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="atmelavr32"><b>Atmel AVR32</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>AV32DEV1</b>.
      This port uses the www.mcuzone.com AVRDEV1 board based on the Atmel AT32UC3B0256 MCU.
      This port requires a special GNU avr32 toolchain available from atmel.com website.
      This is a windows native toolchain and so can be used only under Cygwin on Windows.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         This port is has completed all basic development, but there is more that needs to be done.
         All code is complete for the basic NuttX port including header files for all AT32UC3* peripherals.
         The untested AVR32 code was present in the 5.12 release of NuttX.
         Since then, the basic RTOS port has solidified:
      </p>
      <ul>
        <li>
          The port successfully passes the NuttX OS test (apps/examples/ostest).
        </li>
        <li>
          A NuttShell (NSH) configuration is in place (see the <a href="http://www.nuttx.org/NuttShell.html">NSH User Guide</a>).
          Testing of that configuration has been postponed (because it got bumped by the Olimex LPC1766-STK port).
          Current Status: I think I have a hardware problem with my serial port setup.
          There is a good chance that the NSH port is complete and functional, but I am not yet able to demonstrate that.
          At present, I get nothing coming in the serial RXD line (probably because the pins are configured wrong or I have the MAX232 connected wrong).
        </li>
      </ul>
      <p>
        The basic, port (including the verified apps/examples/ostest configuration) was be released in NuttX-5.13.
        A complete port will include drivers for additional AVR32 UC3 devices -- like SPI and USB --- and will be available in a later release,
        time permitting.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="m68hcs12"><b>Freescale M68HCS12</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>MC9S12NE64</b>.
      Support for the MC9S12NE64 MCU and two boards are included:
    </p>
    <ul>
      <li>
        The Freescale DEMO9S12NE64 Evaluation Board, and
      </li>
      <li>
        The Future Electronics Group NE64 /PoE Badge board.
      </li>
    </ul>
    <p>
      Both use a GNU arm-elf toolchain* under Linux or Cygwin.
      The NuttX <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a> provides a properly patched GCC 3.4.4 toolchain that is highly optimized for the m9s12x family.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         Coding is complete for the MC9S12NE64 and for the NE64 Badge board.
         However, testing has not yet begun due to issues with BDMs, Code Warrior, and
         the paging in the build process.
         Progress is slow, but I hope to see a fully verified MC9S12NE64 port in the near future.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="8052"><b>Intel 8052 Microcontroller</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PJRC 87C52 Development Board</b>.
      This port uses the <a href="http://www.pjrc.com/">PJRC</a> 87C52 development system
      and the <a href="http://sdcc.sourceforge.net/">SDCC</a> toolchain under Linux or Cygwin.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
        This port is complete but not stable with timer interrupts enabled.
        There seems to be some issue when the stack pointer enters into the indirect IRAM
        address space during interrupt handling.
        This architecture has not been built in some time will likely have some compilation
        problems because of SDCC compiler differences.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="80x86"><b>Intel 80x86</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>QEMU/Bifferboard i486</b>.
      This port uses the <a href="http://wiki.qemu.org/Main_Page">QEMU</a> i486 and the native
      Linux, Cywgin, MinGW the GCC toolchain under Linux or Cygwin.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         The basic port was code-complete in NuttX-5.19 and verifed in NuttX-6.0.
         The port was verified using the OS and NuttShell (NSH) examples under QEMU.
         The port is reported to be functional on the <a href="http://bifferos.bizhat.com">Bifferboard</a> as well.
         This is a great, stable starting point for anyone interest in fleshing out the x86 port!
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>RGMP</b>.
      RGMP stands for RTOS and GPOS on Multi-Processor.
      RGMP is a project for  running GPOS and RTOS simultaneously on multi-processor platforms
      You can port your favorite RTOS to RGMP together with an unmodified Linux to form a hybrid operating system.
      This makes your application able to use both RTOS and GPOS features.
    </p>
    <p>
      See the <a href="http://rgmp.sourceforge.net/wiki/index.php/Main_Page">RGMP Wiki</a> for further information about RGMP.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         This initial port of NuttX to RGMP was provided in NuttX-6.3.
         This initial RGP port provides only minimal driver support and does not use the native NuttX interrupt system.
         This is a great, stable starting point for anyone interest in working with NuttX under RGMP!
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="pic32mips"><b>MicroChip PIC32 (MIPS)</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PIC32MX460F512L</b>.
      A port of NuttX to the PIC32MX460F512L is underway.
      This port uses the PIC32MX board from PCB Logic Design Co.
      The board is a very simple -- little more than a carrier for the PIC32 MCU plus voltage regulation, debug interface, and an OTG connector.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
       This port is code complete and has begun testing.
       Testing is, unfortunately, delayed until I obtain some additional test equipment
       (you can't use PICkit 2 with the PIC32; you need PICkit 3.  And, to make things worse,
       my PICKit3 just hangs when I try to debug).
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PIC32MX440F512H</b>.
        This port uses the &quot;Advanced USB Storage Demo Board,&quot; Model DB-DP11215, from <a href="http://www.sureelectronics.net">Sure Electronics</a>.
        This board features the MicroChip PIC32MX440F512H.  See the <a href="http://www.sureelectronics.net/goods.php?id=1168">Sure website</a> for further    information about the DB-DP11215 board.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
       This port is code complete and has begun testing.
       I hope to use the on-board LEDs to work around the debug problems with the PCL Logic board (see above).
       Update: Work on this board has stalled due to higher priority tasks.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Development Environment:</b>
      These ports uses the <i>LITE</i> version of the PIC32MX toolchain available
      for download from the <a href="http://www.microchip.com">MicroChip</a> website.
    </p>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><br></td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="superh"><b>Renesas/Hitachi SuperH</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>SH-1 SH7032</b>.
      This port uses the Hitachi SH-1 Low-Cost Evaluation Board (SH1_LCEVB1), US7032EVB,
      with a GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
        This port is available as of release 0.3.18 of NuttX.  The port is basically complete
        and many examples run correctly.  However, there are remaining instabilities that
        make the port un-usable.  The nature of these is not understood; the behavior is
        that certain SH-1 instructions stop working as advertised.  This could be a silicon
        problem, some pipeline issue that is not handled properly by the gcc 3.4.5 toolchain
        (which has very limit SH-1 support to begin with), or perhaps with the CMON debugger.
        At any rate, I have exhausted all of the energy that I am willing to put into this cool
        old processor for the time being.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="m16c"><b>Renesas M16C/26</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Renesas M16C/26 Microncontroller</b>.
      This port uses the Renesas SKP16C26 Starter kit and the GNU M32C toolchain. 
      The development environment is either Linux or Cygwin under WinXP.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Initial source files released in nuttx-0.4.2.
        At this point, the port has not been integrated;    the target cannot be built
        because the GNU <code>m16c-elf-ld</code> link fails with  the following message:
      </p>
      <ul>
      <code>m32c-elf-ld: BFD (GNU Binutils) 2.19 assertion fail /home/Owner/projects/nuttx/buildroot/toolchain_build_m32c/binutils-2.19/bfd/elf32-m32c.c:482</code>
      </ul>
      <p>Where the reference line is:</p>
      <ul><pre>
/* If the symbol is out of range for a 16-bit address,
   we must have allocated a plt entry.  */
BFD_ASSERT (*plt_offset != (bfd_vma) -1);
</pre></ul>
      <p>
        No workaround is known at this time.  This is a show stopper for M16C for
        the time being.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogz16f"><b>Zilog Z16F</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Zilog z16f Microncontroller</b>.
      This port use the Zilog z16f2800100zcog development kit and the Zilog
      ZDS-II Windows command line tools.
      The development environment is Cygwin under WinXP.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        The initial release of support for the z16f was made available in NuttX version 0.3.7.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogez80acclaim"><b>Zilog eZ80 Acclaim!</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Zilog eZ80Acclaim! Microncontroller</b>.
      There are two eZ80Acclaim! ports:
    </p>
    <ul>
      <li>One uses the ZiLOG ez80f0910200kitg development kit, and
      <li>The other uses the ZiLOG ez80f0910200zcog-d development kit.
    </ul>
    <p>
      Both boards are based on the eZ80F091 part and both use the Zilog ZDS-II
      Windows command line tools.
      The development environment is Cygwin under WinXP.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Integration and testing of NuttX on the  ZiLOG ez80f0910200zcog-d is complete.
        The first integrated version was released in NuttX version 0.4.2 (with important early bugfixes
        in 0.4.3 and 0.4.4).
        As of this writing, that port provides basic board support with a serial console, SPI, and eZ80F91 EMAC driver.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogz8encore"><b>Zilog Z8Encore!</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Zilog Z8Encore! Microncontroller</b>.
      This port uses the either:
    </p>
    <ul>
      <li>Zilog z8encore000zco development kit, Z8F6403 part, or</li>
      <li>Zilog z8f64200100kit development kit, Z8F6423 part</li>
    </ul>
    <p>
      and the Zilog ZDS-II Windows command line tools.
      The development environment is Cygwin under WinXP.
    </p>
    <ul>
       <p>
         <b>STATUS:</b>
         This release has been verified only on the ZiLOG ZDS-II Z8Encore! chip simulation
         as of nuttx-0.3.9.
       </p>
     <ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogz80"><b>Zilog Z80</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Z80 Instruction Set Simulator</b>.
      This port uses the <a href="http://sdcc.sourceforge.net/">SDCC</a> toolchain
      under Linux or Cygwin (verified using version 2.6.0).
      This port has been verified using only a Z80 instruction simulator.
      That simulator can be found in the NuttX SVN
      <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/misc/sims/z80sim/">here</a>.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
        This port is complete and stable to the extent that it can be tested
        using an instruction set simulator.
      </p>
    <ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>XTRS: TRS-80 Model I/III/4/4P Emulator for Unix</b>.
      A very similar Z80 port is available for <a href="http://www.tim-mann.org/xtrs.html">XTRS</a>,
      the TRS-80 Model I/III/4/4P Emulator for Unix.
      That port also uses the <a href="http://sdcc.sourceforge.net/">SDCC</a> toolchain
      under Linux or Cygwin (verified using version 2.6.0).
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
       Basically the same as for the Z80 instruction set simulator.
       This port was contributed by Jacques Pelletier.
      </p>
    <ul>
  </td>
</tr>
</table></center>

<blockquote>* A highly modified <a href="http://buildroot.uclibc.org/">buildroot</a>
is available that may be used to build a NuttX-compatible ELF toolchain under
Linux or Cygwin.  Configurations are available in that buildroot to support ARM, Cortex-M3,
avr, m68k, m68hc11, m68hc12, m9s12, blackfin, m32c, h8, and SuperH ports.</blockquote>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="environments"><h1>Development Environments</h1></a>
  </td>
  </tr>
</table>

<center><table width="90%">
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Linux + GNU <code>make</code> + GCC/binutils</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      The is the most natural development environment for NuttX.
      Any version of the GCC/binutils toolchain may be used.
      There is a  highly modified <a href="http://buildroot.uclibc.org/">buildroot</a>
      available for download from the
      <a href="http://sourceforge.net/project/showfiles.php?group_id=189573">NuttX SourceForge</a>
      page.
      This download may be used to build a NuttX-compatible ELF toolchain under Linux or Cygwin.
      That toolchain will support ARM, m68k, m68hc11, m68hc12, and SuperH ports.
      The buildroot SVN may be accessed in the 
      <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/misc/buildroot/">NuttX SVN</a>.
    </p>
   </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Linux + GNU <code>make</code> + SDCC</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Also very usable is the Linux environment using the 
      <a href="http://sdcc.sourceforge.net/">SDCC</a> compiler.
      The SDCC compiler provides support for the 8051/2, z80, hc08, and other microcontrollers.
      The SDCC-based logic is less well exercised and you will likely find some compilation
      issues if you use parts of NuttX with SDCC that have not been well-tested.
    </p>
   </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Cygwin + GNU <code>make</code> + GCC/binutils</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      This combination works well too.
      It works just as well as the native Linux environment except
      that compilation and build times are a little longer.
      The custom NuttX <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a> referenced above may be build in
      the Cygwin environment as well.
    </p>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Cygwin + GNU <code>make</code> + SDCC</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
       I have never tried this combination, but it would probably work just fine.
    </p>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Cygwin + GNU <code>make</code> + Windows Native Toolchain</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      This is a tougher environment.
      In this case, the Windows native toolchain is unaware of the
      Cygwin <i>sandbox</i> and, instead, operates in the native Windows environment.
      The primary difficulties with this are:
    </p>
    <ul>
      <li>
        <b>Paths</b>.
        Full paths for the native toolchain must follow Windows standards.
        For example, the path <code>/home/my\ name/nuttx/include</code> my have to be
        converted to something like <code>'C:\cygwin\home\my name\nuttx\include'</code>
        to be usable by the toolchain.
      </li>
      <p>
        Fortunately, this conversion is done simply using the <code>cygpath</code> utility.
      </p>
      <li>
        <b>Symbolic Links</b>
        NuttX depends on symbolic links to install platform-specific directories in the build system.
        On Linux, true symbolic links are used.
        On Cygwin, emulated symbolic links are used.
        Unfortunately, for native Windows applications that operate outside of the
        Cygwin <i>sandbox</i>, these symbolic links cannot be used.
      </li>
      <p>
        The NuttX make system works around this limitation by copying the platform
        specific directories in place.
        These copied directories make work a little more complex, but otherwise work well.
      </p>
      <p><small>
        NOTE: In this environment, it should be possible to use the NTFS <code>mklink</code> command to create links.
        This should only require a minor modification to the build scripts (see <code>tools/winlink.sh</code> script).
      </small></p>
      <li>
        <b>Dependencies</b>
        NuttX uses the GCC compiler's <code>-M</code> option to generate make dependencies.  These
        dependencies are retained in files called <code>Make.deps</code> throughout the system.
        For compilers other than GCC, there is no support for making dependencies in this way.
        For Windows native GCC compilers, the generated dependencies are windows paths and not
        directly usable in the Cygwin make.  By default, dependencies are surpressed for these
        compilers as well.
      </li>
      <p><small>
        NOTE: dependencies are suppress by setting the make variable <code>MKDEPS</code> to point
        to the do-nothing dependency script, <code>tools/mknulldeps.sh</code>.
        Dependencies can be enabled for the Windows native GCC compilers by setting
        <code>MKDEPS</code> to point to <code>$(TOPDIR)/tools/mkdeps.sh --winpaths $(TOPDIR)</code>.
      </small></p>
    </ul>
    <p>
      <b>Supported Windows Native Toolchains</b>.
      At present, only the Zilog Z16F, z8Encore, and eZ80Acclaim ports use a non-GCC native Windows
      toolchain(the Zilog ZDS-II toolchain).
      Support for Windows native GCC toolchains (CodeSourcery and devkitARM) is currently implemented
      for the NXP LPC214x, STMicro STR71x, and Luminary LMS6918 ARM ports.
      (but could easily be extended to any other GCC-based platform with a small effort).
    </p>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Wine + GNU <code>make</code> + Windows Native Toolchain</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      I've never tried this one, but I off the following reported by an ez80 user using the ZiLOG ZDS-II Windows-native toolchain:
    </p>
    <blockquote>
      <p>
         &quot;I've installed ZDS-II 5.1.1 (IDE for ez80-based boards) on wine (windows emulator for UNIX) and to my surprise, not many changes were needed to make SVN snapshot of Nuttx buildable...
         I've tried nsh profile and build process completed successfully.
         One remark is necessary: Nuttx makefiles for ez80 are referencing <code>cygpath</code> utility.
         Wine provides similar thing called <code>winepath</code> which is compatible and offers compatible syntax.
         To use that, <code>winepath</code> (which itself is a shell script) has to be copied as <code>cygpath</code> somewhere in <code>$PATH</code>, and edited as in following patch:
       </p>
       <ul><pre>
# diff -u `which winepath` `which cygpath`
--- /usr/bin/winepath 2011-05-02 16:00:40.000000000 +0200
+++ /usr/bin/cygpath 2011-06-22 20:57:27.199351255 +0200
@@ -20,7 +20,7 @@
#

# determine the app Winelib library name
-appname=`basename "$0" .exe`.exe
+appname=winepath.exe

# first try explicit WINELOADER
if [ -x "$WINELOADER" ]; then exec "$WINELOADER" "$appname" "$@"; fi
</pre></ul>
      <p>
        &quot;Better solution would be replacing all <code>cygpath</code> references in  <code>Makefiles </code> with  <code>$(CONVPATH)</code> (or  <code>${CONVPATH}</code> in shell scripts) and setting <code>CONVPATH</code> to  <code>cygpath</code> or  <code>winepath</code> regarding to currently used environment.
      </p>
    </blockquote>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Other Environments?
    Windows Native <code>make</code> + Windows Native Toolchain?</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Environment Dependencies</b>.
      The primary environmental dependency of NuttX are (1) GNU make,
      (2) bash scripting, and (3) Linux utilities (such as cat, sed, etc.).
      If you have other platforms that support GNU make or make
      utilities that are compatible with GNU make, then it is very
      likely that NuttX would work in that environment as well (with some
      porting effort). If GNU make is not supported, then some significant
      modification of the Make system would be required.
    </p>
    <p>
     <b>GNUWin32</b>.
      For example, with suitable make system changes, it should be possible to
      use native GNU tools (such as those from
      <a href="http://sourceforge.net/projects/gnuwin32/">GNUWin32</a>)
      to build NuttX.
      However, that environment has not been used as of this writing.
   </p>
      <p><small>
        NOTE: One of the members on the <a href="http://tech.groups.yahoo.com/group/nuttx/">NuttX forum</a>
        reported that they successful built NuttX using such a GNUWin32-based, Windows native environment.
        They reported that the only necessary change was to the use the NTFS mklink command to create links
        (see <code>tools/winlink.sh</code> script).
      </small></p>
  </td>
</tr>
</table></center>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="footprint"><h1>Memory Footprint</h1></a>
  </td>
  </tr>
</table>

<ul>
<p><b>C5471 (ARM7)</b>
  The build for this ARM7 target that includes most of the OS features and
  a broad range of OS tests.  The size of this executable as given by the
  Linux <tt>size</tt> command is (3/9/07):
</p>
<pre>
   text    data     bss     dec     hex filename
  53272     428    3568   57268    dfb4 nuttx
</pre>
<p><b>DM320 (ARM9)</b>
  This build for the ARM9 target includes a significant subset of OS
  features, a filesystem, Ethernet driver, full TCP/IP, UDP and (minimal)
  ICMP stacks (via uIP) and a small network test application: (11/8/07,
  configuration netconfig, apps/examples/nettest)
</p>
<pre>
   text    data     bss     dec     hex filename
  49472     296    3972   53740    d1ec nuttx
</pre>
<p>
  Another build for the ARM9 target includes a minimal OS feature
  set, Ethernet driver, full TCP/IP and (minimal) ICMP stacks, and
  a small webserver: (11/20/07, configuration uipconfig, apps/examples/uip)
</p>
<pre>
   text    data     bss     dec     hex filename
  52040      72    4148   56260    dbc4 nuttx
</pre>
<p><b>87C52</b>
  A reduced functionality OS test for the 8052 target requires only
  about 18-19Kb:
</p>
<pre>
Stack starts at: 0x21 (sp set to 0x20) with 223 bytes available.

Other memory:
   Name             Start    End      Size     Max
   ---------------- -------- -------- -------- --------
   PAGED EXT. RAM                         0      256
   EXTERNAL RAM     0x0100   0x02fd     510     7936
   ROM/EPROM/FLASH  0x2100   0x6e55   19798    24384
</pre>
</ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="licensing"><h1>Licensing</h1></a>
  </td>
  </tr>
</table>

<ul>
<p>
  NuttX is available under the highly permissive
  <a href="http://en.wikipedia.org/wiki/BSD_license">BSD license</a>.
  Other than some fine print that you agree to respect the copyright
  you should feel absolutely free to use NuttX in any environment and
  without any concern for jeopardizing any proprietary software that
  you may link with it.
</p>
</ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="history"><h1>Release History</h1></a>
  </td>
  </tr>
</table>

<ul>
<p>
   The current NuttX Change Log is available in SVN <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/nuttx/ChangeLog?view=log">here</a>.
   ChangeLog snapshots associated with the current release are available below.
</p>
</ul>

<center><table width ="80%">
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
   <td>
      <a href="ChangeLog.txt">Change Logs for All NuttX Releases</a><br>
   </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
   <td>
      <a href="#currentrelease">ChangeLog for the Current Releases</a><br>
   </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
   <td>
      <a href="#pendingchanges">Unreleased Changes</a>
   </td>
</tr>
</table></center>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="currentrelease">ChangeLog for the Current Release</a>
  </td>
  </tr>
</table>

<ul><pre>
nuttx-6.7 2011-08-02 Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

    * Makefile:  Added a export target that will bundle up all of the NuttX
      libraries, header files, and the startup object into an export-able
      tarball.
    * arch/arm/src/lpc17xx/lpc17_can.h:  Correct some typos in the CAN
      register definitions.
    * drivers/serial/serialirq.c:  Correct an error that can occur if the
      serial RX buffer becomes full.  Data is now discarded in that case;
      before, leaving data in the hardware would cause infinite interrupts
      one most MCUs since you must read the data in order to clear the
      interrupt.
    * arch/arm/src/lpc17xx/lpc17_can.c:  Added a CAN driver contributed by
      Li Zhuoyi (Lzyy).
    * include/stddefs.h and sys/types:  Added type wchar_t.
    * fs/fat/fat_fat32dirent.c:  Move all FAT directory operations to this
      new file; Implement VFAT long file name support.
    * fs/fat/fat_fat32dirent.c:  The configuration CONFIG_FAT_LCNAMES has
      been around for some time but never tested until now.  This setting
      will mimic the NT 8.3 file name behavior:  File names or extensions 
      may be all upper or all lower case (but not mixed).  If
      CONFIG_FAT_LCNAMES is not selected, all filenames are strictly upper
      case.
    * configs/stm3210e-eval/nsh2:  Console is back on UART1; Added
      examplex/nx as an NSH &quot;built-in&quot; command as a demonstration.
    * fs/fat/fs_fat32dirent.c:  Fix an important bug in the directory
      allocation (fat_allocatedirentry()).  I looks like it could be
      initializing the wrong sectors! NOTE:  This function was in
      fs_fat32utils.c in earlier releases.
    * arch/arm/src/stm32_sdio.c: Correct an important DMA-related bug;
      SDIO transfer completion events and DMA completion eventes were
      not being coordinated correctly.
    * configs/stm3210e-eval/nsh2: Enable FAT long file name support
    * sched/sem_timedwait.c: Add the standard sem_timedwait() interface.
    * graphics/nxfonts/nxfonts_getfont.c, nxfonts_bitmap.c,
      Makefile.source, and include/nuttx/nxfonts.h: Support for multiple
      fonts included.  A new interface, nxf_getfonthandle() takes a font
      ID and returns a handle that is now used at all other font interfaces
      to specify which of the multiple fonts to use.
    * arch/arm/src/lpc17xx/lpc17_syscon.h: Fix typo (reported by Li Zhuoyi).
    * configs/stm3210e-eval/nsh2: Extended to support two new commands:
      'msconn' will connect the USB mass storage device; 'msdis' will
      disconnect the USB storage device.
    * tools/bdf-converter.c.  This C file is used to build the bdf-converter
      program.  The bdf-converter program be used to convert fonts in Bitmap
      Distribution Format (BDF) into fonts that can be used in the NX graphics
      system.
    * include/nuttx/nx:  Move all NX header files from include/nuttx to 
      include/nuttx/nx.
    * drivers/usbdev/usbdev_usbstorage.c and arch/arm/src/stm32/stm32_usbdev.c:
      Correct a memory leak when the USB mass storage driver is connected and
      then disconnected from the target.  The write requests were not being
      freed.  NOTE that the unregister logic in the STM32 needed to call
      stm32_reset() in order to return the write requests to the USB mass
      storage driver; it is possible that a similar but could exist for other
      architectures.
    * graphics/nxfonts/nxfonts_*.h:  Add serveral more new fonts
    * arch/z80/src/ez80/ez80_serial.c: Fix some errors in serial driver
      setup for UART1 (submitted by Paul Osmialowski).
    * drivers/input/tsc2007.c and include/nuttx/input/*:  Add a generic NuttX
      touchscreen interface.  Add a driver for the TI TSC2007 touchscreen
      controller.
    * graphics/nxglib/lcd and fb:  Add low level routines to set single pixels.
    * lib/math/lib_b16atan2.c:  Add a fixed precision atan2() function
    * graphics/nxglib/nxglib_splitline.c: Add logic to divide a wide line into
      trapezoidal components.
    * graphics/nxmu/nx_drawline.c, graphics/nxsu/nx_drawline.c,
      graphics/nxtk/nxtk_drawlinewindow.c, graphics/nxtk/nxtk_drawlinetoolbar.c:
      Add new line drawing interfaces (untested).

apps-6.7 2011-08-02 Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

    * apps/examples/nx and nxtext:  These examples can now be built as NSH
      &quot;built-in&quot; commands.
    * apps/examples/nxhello:  The simplest graphics example:  It just says
      &quot;Hello, World!&quot; in the center of the display. This example can also be
      built as an NSH &quot;built-in&quot; command.
    * apps/examples/nx, ntext, and nxhello:  All updated to use the new
      NuttX font interfaces.
    * apps/examples/nximage:  Another super simple  graphics example:  It just puts
      the NuttX logo in the center of the display. This example can also be
      built as an NSH &quot;built-in&quot; command.
    * apps/examples/usbstorage: Can now be built as two NSH &quot;built-in&quot; commands:
      'msconn' will connect the USB mass storage device; 'msdis' will disconnect
      the USB storage device.
    * apps/examples/nx*:  All NX header files moved from nuttx/include/nuttx to 
      nuttx/include/nuttx/nx.
    * apps/examples/usbstorage: Added instrumentation to monitor memory usage
      to check for memory leaks in the USB storage driver.
    * apps/examples/nxhello/nxhello_bkgd.c:  Fix handling of allocated glyph
      memory.

pascal-1.0 2011-05-15 Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

    * nuttx/:  The Pascal add-on module now installs and builds under the
      apps/interpreters directory.  This means that the pascal-2.1 module is
      incompatible with will all releases of NuttX prior to nuttx-6.0 where the 
      apps/ module was introduced.

buildroot-1.10 2011-05-06 &lt;spudmonkey@racsa.co.cr&gt;

    * Add patch submitted by Dimiter Georgiev to work around problems in building
      GDB 6.8 with versions of Cygwin &gt; 1.7.
    * configs/i486-defconfig-4.3.3 - Builds an i486 cross development toolchain
      using gcc 4.3.3.  Why wouldyou want such a thing?  On Linux, of course,
      such a thing is not needed because you can use the installed GCC to build
      i486 ELF binaries.  But that will not work under Cygwin!  The Cygwin
      toolchain (and probably MinGW), build DOS MZ format executables (i.e.,
      .exe files).  That is probably not usable for most NuttX targets.
      Instead, you should use this i486-elf-gcc to generate true ELF binaries
      under Cygwin.
    * Makefile - Alter copy arguments to avoid permissions problems when
      copying NuttX header files.
    * toolchain/nxflat/nxflat.mk and Makefile - Fix include paths.
    * toolchain/gcc/3.3.6 - Added a patch to fixed compilation error on Ubuntu
      9.10.
    * toolchain/nxflat/Makefile - Correct static library link order.
    * configs/arm920t-defconfig-4.3.3 - Enable support for NXFLAT tools.
    * toolchain/binutils/2.21 and toolchain/gcc/4.5.2 - Add support for GCC
      4.5.2 with binutils 2.21.
    * configs/arm920t-eabi-defconfig-4.5.2 - Add a configuration to build a
      GCC 4.5.2 EABI ARM toolchain for the ARM920t.
</pre></ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="pendingchanges">Unreleased Changes</a>
  </td>
  </tr>
</table>

<ul><pre>
nuttx-6.8 2011-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

apps-6.8 2011-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

pascal-3.1 2011-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

buildroot-1.11 2011-xx-xx &lt;spudmonkey@racsa.co.cr&gt;
</pre></ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="TODO"><h1>Bugs, Issues, <i>Things-To-Do</i></h1></a>
  </td>
  </tr>
</table>

<ul>
<p>
   The current list of NuttX <i>Things-To-Do</i> in SVN <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/nuttx/TODO?view=log">here</a>.
   A snapshot of the <i>To-Do</i> list associated with the current release are available <a href="TODO.txt">here</a>.
</p>
</ul>
<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="documentation"><h1>Other Documentation</h1></a>
  </td>
  </tr>
</table>

<ul><table>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttxUserGuide.html">User Guide</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttxPortingGuide.html">Porting Guide</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttShell.html">NuttShell (NSH)</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttXNxFlat.html">NXFLAT</a> Binary Format</td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NXGraphicsSubsystem.html">NX Graphics Subsystem</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttXDemandPaging.html">Demand Paging</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="README.html">NuttX README Files</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="ChangeLog.txt">Change Log</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="TODO.txt">To-Do List</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="UsbTrace.html">USB Device Driver Tracing</a></td>
</tr>
</center></ul>

<small>
<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="trademarks"><h1>Trademarks</h1></a>
  </td>
  </tr>
</table>
<ul>
  <li>ARM, ARM7 ARM7TDMI, ARM9, ARM920T, ARM926EJS Cortex-M3 are trademarks of Advanced RISC Machines, Limited.</li>
  <li>Cygwin is a trademark of Red Hat, Incorporated.</li>
  <li>Linux is a registered trademark of Linus Torvalds.</li>
  <li>Eagle-100 is a trademark of <a href=" http://www.micromint.com/">Micromint USA, LLC</a>.
  <li>LPC2148 is a trademark of NXP Semiconductors.</li>
  <li>TI is a tradename of Texas Instruments Incorporated.</li>
  <li>UNIX is a registered trademark of The Open Group.</li>
  <li>VxWorks is a registered trademark of Wind River Systems, Incorporated.</li>
  <li>ZDS, ZNEO, Z16F, Z80, and Zilog are a registered trademark of Zilog, Inc.</li>
</ul>
<p>
  NOTE: NuttX is <i>not</i> licensed to use the POSIX trademark.  NuttX uses the POSIX
  standard as a development guideline only.
</p>
</small>

</body>
</html>
<html>
<head>
<title>NuttX</title>
</head>
<body background="backgd.gif">
<hr><hr>
<table width ="100%">
  <tr align="center" bgcolor="#e4e4e4">
    <td>
      <h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
      <p>Last Updated: August 1, 2011</p>
    </td>
  </tr>
</table>
<hr><hr>
<table width ="100%">
  <tr bgcolor="#e4e4e4">
    <td>
  <h1>Table of Contents</h1>
    </td>
  </tr>
</table>

<center><table width ="80%">
<tr>
<td>
<table>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#overview">Overview</a>.<br>
    What is NuttX?  Look at all those files and features... How can it be a tiny OS?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#group">NuttX Discussion Group</a>.<br>
    Do you want to talk about NuttX features?  Do you need some help?  Problems?  Bugs?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#downloads">Downloads</a>.<br>
    Where can I get NuttX?  What is the current development status?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#platforms">Supported Platforms</a>.<br>
    What target platforms has NuttX been ported to?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#environments">Development Environments</a>.<br>
    What kinds of host cross-development platforms can be used with NuttX?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#footprint">Memory Footprint</a>.<br>
    Just how big is it?  Do I have enough memory to use NuttX?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#licensing">Licensing</a>.<br>
    Are there any licensing restrictions for the use of NuttX? (Almost none)
    Will there be problems if I link my proprietary code with NuttX? (No)
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#history">Release History</a><br>
    What has changed in the last release of NuttX?
    What unreleased changes are pending in SVN?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#TODO">Bugs, Issues, <i>Things-To-Do</i></a>.<br>
    Software is never finished nor ever tested well enough.
    (Do you want to help develop NuttX?  If so, send me an email).
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#documentation">Other Documentation</a>.<br>
    What other NuttX documentation is available?
  </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td>
    <a href="#trademarks">Trademarks</a>.<br>
    Some of the words used in this document belong to other people.
  </td>
</tr>
</table>
</td>
</tr>
</table></center>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="overview"><h1>Overview</h1></a>
  </td>
  </tr>
</table>

<p>
  <b>Goals</b>.
  Nuttx is a real timed embedded operating system (RTOS).
  Its goals are:
<p>
<center><table width="90%">
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Small Footprint</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Usable in all but the tightest micro-controller environments,
      The focus is on the tiny-to-small, deeply embedded environment.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Rich Feature OS Set</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      The goal is to provide implementations of most standard POSIX OS interfaces
      to support a rich, multi-threaded development environment for deeply embedded
      processors.
    </p>
      NON-GOALS: (1) It is not a goal to provide the rich level of OS
      features like those provided with Linux.
      Small footprint is more important than features.
      Standard compliance is more important than small footprint.
      (2) There is no MMU-based support for processes.
      At present, NuttX assumes a flat address space.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Highly Scalable</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Fully scalable from tiny (8-bit) to moderate embedded (32-bit).
      Scalability with rich feature set is accomplished with:
      Many tiny source files, link from static libraries, highly configurable, use of
      weak symbols when available.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Standards Compliance</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      NuttX strives to achieve a high degree of standards compliance.
      The primary governing standards are POSIX and ANSI standards.
      Additional standard APIs from Unix and other common RTOS's are
      adopted for functionality not available under these standards
      or for functionality that is not appropriate for the deeply-embedded
      RTOS (such as <code>fork()</code>).
    </p>
    <p>
      Because of this standards conformance, software developed under other
      standard OSs (such as Linux) should port easily to NuttX.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Real-Time</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Fully pre-emptible, fixed priority and round-robin scheduling.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Totally Open</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Non-restrictive BSD license.
    </p>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>GNU Toolchains</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Compatible GNU toolchains based on <a href="http://buildroot.uclibc.org/">buildroot</a>
      available for
      <a href="https://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">download</a>
      to provide a complete development environment for many architectures.
    </p>
</tr>
</table></center>

<p>
  <b>Feature Set</b>.
  Key features of NuttX include:
<p>
<center><table width="90%">

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Standards Compliant Core Task Management</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Modular, micro-kernel</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Fully pre-emptible.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Naturally scalable.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Highly configurable.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Easily extensible to new processor architectures, SoC architecture, or board architectures.
          A <a href="NuttxPortingGuide.html">Porting Guide</a> is in development.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>FIFO and round-robin scheduling.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Realtime, deterministic, with support for priority inheritance</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>POSIX/ANSI-like task controls, named message queues, counting semaphores, clocks/timers, signals, pthreads, environment variables, filesystem.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>VxWorks-like task management and watchdog timers.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>BSD socket interface.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Extensions to manage pre-emption.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>On-demand paging.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>May be built either as an open, flat embedded RTOS or as a separtely built, secure micro-kernel with a system call interface.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Well documented in the NuttX <a href="NuttxUserGuide.html">User Guide</a>.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>File system</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Tiny in-memory, root pseudo-file-system.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Supports character and block drivers.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>Network, USB (host), USB (device), serial, CAN, driver architectures.</li>
    </p>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>RAMDISK, pipes, FIFO, <code>/dev/null</code>, <code>/dev/zero</code> drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Mount-able volumes.  Bind mountpoint, filesystem, and block device driver.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>FAT12/16/32 filesystem support with optional FAT long file name support<small><sup>1</sup></small>.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>NXFFS. the NuttX wear-leveling FLASH file system.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Generic driver for SPI-based MMC/SD/SDH cards.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>ROMFS filesystem support.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><a href="NuttXNxFlat.html">NXFLAT</a>.
      A new binary format call NXFLAT that can be used to 
      execute separately linked programs in place in a file system.
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p><small>
      <sup>1</sup>
      FAT long file name support may be subject to certain Microsoft patent restrictions if enabled.
      See the top-level <code>COPYING</code> file for details.
    </small></p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>C Library</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Fully integrated into the OS.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Networking</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>TCP/IP, UDP, ICMP, IGMPv2 (client) stacks.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>SLIP</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Small footprint (based on uIP).</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>BSD compatible socket layer.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Networking utilities (DHCP server and client, SMTP client, TELNET client, FTP client, TFTP client, HTTP server and client)</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>
        A NuttX port of Jeff Poskanzer's <a href="http://acme.com/software/thttpd">THTTPD</a> HTTP server
        integrated with <a href="NuttXNxFlat.html">NXFLAT</a> to provide true, embedded CGI.
      </li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>FLASH Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><i>MTD</i>-inspired interface for <i>M</i>emory <i>T</i>echnology <i>D</i>evices.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><i>FTL</i>.  Simple <i>F</i>lash <i>T</i>ranslation <i>L</i>ayer support file systems on FLASH.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>NXFFS. the NuttX wear-leveling FLASH file system.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Support for SPI-based FLASH and FRAM devices.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>USB Host Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>USB host architecture for USB host controller drivers and device-dependent USB class drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>USB host controller drivers available for the NXP LPC17xx.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Device-dependent USB class drivers available for USB mass storage and HID keyboard.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>USB Device Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li><i>Gadget</i>-like architecture for USB device controller drivers and device-dependent USB class drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>USB device controller drivers available for the NXP LPC17xx, LPC214x, LPC313x, STMicro STM32 and TI DM320.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Device-dependent USB class drivers available for USB serial and for USB mass storage.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Built-in <a href="UsbTrace.html">USB trace</a> functionality for USB debug.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Graphics Support</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Framebuffer drivers.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>LCD drivers for both parallel and SPI LCDs and OLEDs.</li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>
         NX: A graphics library, tiny windowing system and tiny font support that works with either framebuffer or LCD drivers.
         Documented in the <a href="NXGraphicsSubsystem.html">NX Graphics Subsystem</a>
         manual.
      </li>
    </p>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Font management sub-system.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Input Devices</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <li>Touchscreen, USB keyboard, GPIO-based buttons and keypads. </li>
    </p>
</tr>
</table></center>

<p>
  <b>NuttX Add-Ons</b>.
  The following packages are available to extend the basic NuttX feature set:
</p>
<center><table width="90%">

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>NuttShell (NSH)</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>A small, scalable, bash-like shell for NuttX with rich feature set and small footprint.
        See the <a href="NuttShell.html">NuttShell User Guide</a>.</li>
    </p>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Pascal Compiler with NuttX runtime P-Code interpreter add-on</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      <li>The Pascal add-on is available for download from the
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573">SourceForge</a>
        website.</li>
    </p>
  </td>
</tr>
</table></center>

<p>
  <b>Look at all those files and features... How can it be a tiny OS?</b>.
  The NuttX feature list (above) is fairly long and if you look at the NuttX
  source tree, you will see that there are hundreds of source files comprising
  NuttX.  How can NuttX be a tiny OS with all of that?
</p>
<center><table width="90%">

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Lots of Features -- More can be smaller!</b>
  </td>
</tr>

<tr>
  <td><br></td>
  <td>
    <p>
      The philosophy behind that NuttX is that lots of features are great... <i>BUT</i>
      also that if you don't use those features, then you should not have to pay a penalty
      for the unused features.
      And, with NuttX, you don't!  If you don't use a feature, it will not
      be included in the final executable binary.
      You only have to pay the penalty of increased footprint for the features
      that you actually use.
    </p>
    <p>
      Using a variety of technologies, NuttX can scale from the very tiny to
      the moderate-size system.  I have executed NuttX with some simple applications
      in as little as 32Kb <i>total</i> memory (code and data).
      On the other hand, typical, richly featured NuttX builds require more like 64Kb
      (and if all of the features are used, this can push 100Kb).
    </p>
  </td>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Many, many files -- More really is smaller!</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      One may be intimidated by the size NuttX source tree.  There are hundreds of source files!
      How can that be a tiny OS?
      Actually, the large number of files is one of the tricks to keep NuttX small and
      as scalable as possible.
      Most files contain only a single function. 
      Sometimes just one tiny function with only a few lines of code.
      Why?
    </p>
    <ul>
      <li>
        <b>Static Libraries</b>.
        Because in the NuttX build processed, objects are compiled and saved into
        <i>static libraries</i> (<i>archives</i>).
        Then, when the file executable is linked, only the object files that are needed
        are extracted from the archive and added to the final executable.
        By having many, many tiny source files, you can assure that no code that you do
        not execute is ever included in the link.
        And by having many, tiny source files you have better granularity --
        if you don't use that tiny function of even just a few lines of code, it will
        not be included in the binary.
      </li>
    </ul>
  </td>
</tr>

<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Other Tricks</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      As mentioned above, the use of many, tiny source files and linking from static
      libraries keeps the size of NuttX down.
      Other tricks used in NuttX include:
    </p>
    <ul>
      <li>
         <b>Configuration Files</b>.
         Before you build NuttX, you must provide a configuration file that specifies
         what features you plan to use and which features you do not.
         This configuration file contains a long list of settings that control
         what is built into NuttX and what is not.
         There are hundreds of such settings
         (see the <a href="NuttxPortingGuide.html#apndxconfigs">NuttX Porting Guide</a>
         for a partial list that excludes platform specific settings).
         These many, many configuration options allow NuttX to be highly tuned to
         meet size requirements.
         The downside to all of these configuration options is that it greatly
         complicates the maintenance of NuttX -- but that is my problem, not yours.
      </li>
      <li>
         <b>Weak Symbols</b>
         The GNU toolchain supports <i>weak</i> symbols and these also help to keep
         the size of NuttX down.
         Weak symbols prevent object files from being drawn into the link even if they
         are accessed from source code.
         Careful use of weak symbols is another trick for keep unused code out of the
         final binary.
      </li>
    </ul>
  </td>
</tr>

</table></center>


<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="group"><h1>NuttX Discussion Group</h1></a>
  </td>
  </tr>
</table>

<p>
  Most Nuttx-related discussion occurs on the <a href="http://tech.groups.yahoo.com/group/nuttx/" target="_top"><i>Yahoo!</i> NuttX group</a>.
  You are cordially invited to <a href="http://groups.yahoo.com/group/nuttx/join" target="_top">join</a>.
  I make a special effort to answer any questions and provide any help that I can.
</p>


<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="downloads"><h1>Downloads</h1></a>
  </td>
  </tr>
</table>

<p><b>nuttx-6.7 Release Notes</b>:
<p>
  The 74<sup>th</sup> release of NuttX, Version 6.7, was made on  August 2, 2011, 2011 and is available for download from the
  <a href="http://sourceforge.net/projects/nuttx/files/">SourceForge</a> website.
  Note that release consists of two tarballs:  <code>nuttx-6.7.tar.gz</code> and <code>apps-6.7.tar.gz</code>.
  Both may be needed (see the top-level <code>nuttx/README.txt</code> file for build information)
  The change log associated with the release is available <a href="#currentrelease">here</a>.
  Unreleased changes after this release are available in SVN.
  These unreleased changes are also listed <a href="#pendingchanges">here</a>.
</p>
<p>
  Changes in this release are summarized below:
</p>
<ul>
  <li>
    <b>New OS APIs</b>:
      Add the standard <code>sem_timedwait()</code> interface.
  </li>
  <li>
    <b>FAT File System</b>:
      Adds (optional) support for VFAT long file names.
  </li>
  <li>
    <b>USB</b>:
      Now the mass storage device can be connected when needed and
      disconnected when not needed (or re-connected as a different kind of
      device).
  </li>
  <li>
    <b>Touchscreen Support</b>:
      Defined a new NuttX touchscreen interface.
      Added a driver for the TI TSC2007 touchscreen controller chip.
  </li>
  <li>
    <b>NX Fonts</b>:
      Add support for multiple fonts; developed a tool to
      convert open source fonts into NuttX format; Converted and installed
      nine new, high quality fontsets.
  </li>
  <li>
    <b>NX Graphics</b>:
      Add new NX APIs to support drawing of wide lines in any
      orientation.  Added new low level routines to set individual pixel
      more efficiently.
  </li>
  <li>
    <b>Build system</b>:
      Added a export target that will bundle up all of the
      NuttX libraries, header files, and the startup object into an export-able tarball.
  </li>
  <li>
    <b>LPC17xx</b>:
      A CAN driver was contributed by Li Zhuoyi (Lzyy).
  </li>
  <li>
    <b>STM32</b>:
      New NX-related configurations to excercise text and graphic image displays.
  </li>
  <li>
    <b>C Library</b>:
      Added a fixed precision atan2() math function.
  </li>
  <li>
    <b>Bugfixes</b>:
      Serial RX overrun error, FAT upper/lower NT 8.3 name
      handling fixed.  FAT directory allocation and initialization bug.
      STM32 SDIO DMA race condition bug.  eZ80 UART1 serial driver errors
      (Paul Osmialowski)
  </li>
</ul>
<p>
  See the <a href="#currentrelease">ChangeLog</a> for details.
</p>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="platforms"><h1>Supported Platforms</h1></a>
  </td>
  </tr>
</table>

<p>The short story (Number of ports follow in parentheses. Follow the links for the details):</p>
<center><table width="90%">
<ul>
  <tr>
  <td bgcolor="#e4e4e4" valign="top">
  <li><a href="#linuxusermode">Linux user mode simulation</a> (1)</li>
  <li>ARM
    <ul>
      <li><a href="#arm7tdmi">ARM7TDMI</b></a> (4)</li>
      <li><a href="#arm920t">ARM920T</a> (1) </li>
      <li><a href="#arm926ejs">ARM926EJS</a> (3) </li>
      <li><a href="#armcortexm3">ARM Cortex-M3</a> (10)</li>
    </ul>
  <li>Atmel AVR
    <ul>
      <li><a href="#atmelavr">Atmel 8-bit AVR</a> (3) </li>
      <li><a href="#atmelavr32">Atmel AVR32</a> (1) </li>
    </ul>
  </li>
  </td>
  <td bgcolor="#e4e4e4" valign="top">
  <li>Freescale <a href="#m68hcs12">M68HCS12</a> (2) </li>
  <li>Intel
    <ul>
      <li><a href="#8052">Intel 8052 Microcontroller</a> (1)</li>
      <li><a href="#80x86">Intel 80x86</a> (2)</li>
    </ul>
  </li>
  <li>MicroChip <a href="#pic32mips">PIC32</a> (MIPS) (2)</li>
  <li>Renesas/Hitachi:
    <ul>
        <li><a href="#superh">Renesas/Hitachi SuperH</a> (1/2)</li>
        <li><a href="#m16c">Renesas M16C/26</a> (1/2)</li>
    </ul>
  </li>
  </td>
  <td bgcolor="#e4e4e4" valign="top">
  <li>Zilog
    <ul>
        <li><a href="#zilogz16f">Zilog Z16F</a> (1)</li>
        <li><a href="#zilogez80acclaim">Zilog eZ80 Acclaim!</a> (1)</li>
        <li><a href="#zilogz8encore">Zilog Z8Encore!</a> (2)</li>
        <li><a href="#zilogz80">Zilog Z80</a> (2)</li>
    </ul>
  </li>
</ul>
  </tr>
</table></center>

<p>The details, caveats and fine print follow:</p>

<center><table width="90%">
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="linuxusermode"><b>Linux User Mode</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      A user-mode port of NuttX to the x86 Linux/Cygwin platform is available.
      The purpose of this port is primarily to support OS feature development.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Does not support interrupts but is otherwise fully functional.
      </p>
    </ul>
   </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="arm7tdmi"><b>ARM7TDMI</b></a>.
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>TI TMS320C5471</b> (also called <b>C5471</b> or <b>TMS320DA180</b> or <b>DA180</b>).
      NuttX operates on the ARM7 of this dual core processor.
      This port uses the <a href="http://www.spectrumdigital.com/">Spectrum Digital</a>
      evaluation board with a GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        This port is complete, verified, and included in the initial NuttX release.
      </p>
    </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>NXP LPC214x</b>.
      Support is provided for the NXP LPC214x family of processors.  In particular,
      support is provided for the mcu123.com lpc214x evaluation board (LPC2148).
      This port also used the GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        This port boots and passes the OS test (apps/examples/ostest).
        The port is complete and verified.  As of NuttX 0.3.17, the port includes:
        timer interrupts, serial console, USB driver, and SPI-based MMC/SD card
        support.  A verified NuttShell (<a href="NuttShell.html">NSH</a>)
        configuration is also available.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>NXP LPC2378</b>.
      Support is provided for the NXP LPC2378 MCU.  In particular,
      support is provided for the Olimex-LPC2378 development board.
      This port was contributed by Rommel Marcelo is was first released in NuttX-5.3.
      This port also used the GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        This port boots and passes the OS test (apps/examples/ostest) and includes a
        working implementation of the NuttShell (<a href="NuttShell.html">NSH</a>).
        The port is complete and verified.
        As of NuttX 5.3, the port includes only basic timer interrupts and serial console support.
      </p>
      <p>
        <b>Development Environments:</b> (Same as for the NXP LPC214x).
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>STMicro STR71x</b>.
      Support is provided for the STMicro STR71x family of processors.  In particular,
      support is provided for the Olimex STR-P711 evaluation board.
      This port also used the GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Integration is complete on the basic port (boot logic, system time, serial console).
        Two configurations have been verified: (1) The board boots and passes the OS test
        with console output visible on UART0, and the NuttShell (<a href="NuttShell.html">NSH</a>)
        is fully functional with interrupt driven serial console.  An SPI driver is available
        but only partially tested.  Additional features are needed: USB driver, MMC integration,
        to name two (the slot on the board appears to accept on MMC card dimensions; I have only
        SD cards).
        An SPI-based ENC29J60 Ethernet driver for add-on hardware is under development and
        should be available in the NuttX 5.5 release.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="arm920t"><b>ARM920T</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Freescale MC9328MX1</b> or <b>i.MX1</b>.
      This port uses the Freescale MX1ADS development board with a GNU arm-elf toolchain*
      under either Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          This port has stalled due to development tool issues.
          Coding is complete on the basic port (timer, serial console, SPI).
      </p>
    </ul>
   </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="arm926ejs"><b>ARM926EJS</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>TI TMS320DM320</b> (also called <b>DM320</b>).
      NuttX operates on the ARM9 of this dual core processor.
      This port uses the
      <a href="http://wiki.neurostechnology.com/index.php/Developer_Welcome">Neuros OSD</a>
      with a GNU arm-elf toolchain* under Linux or Cygwin.
      The port was performed using the OSD v1.0, development board.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The basic port (timer interrupts, serial ports, network, framebuffer, etc.) is complete.
          All implemented features have been verified with the exception of the USB device-side
          driver; that implementation is complete but untested.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <b>NXP <a href="http://ics.nxp.com/products/lpc3000/lpc313x.lpc314x.lpc315x/">LPC3131</a></b>.
    The port for the NXP LPC3131 on the <a href="http://www.embeddedartists.com/products/kits/lpc3131_kit.php">Embedded Artists EA3131</a> 
    development board was first released in NuttX-5.1 with a GNU arm-elf or arm-eabi toolchain* under Linux or Cygwin
    (but was not functional until NuttX-5.2).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The basic EA3131 port is complete and verified in NuttX-5.2 
          This basic port includes basic boot-up, serial console, and timer interrupts.
          This port was extended in NuttX 5.3 with a USB high speed driver contributed by David Hewson.
          David also contributed I2C and SPI drivers plus several important LPC313x USB bug fixes
          that appear in the NuttX 5.6 release.
          This port has been verified using the NuttX OS test, USB serial and mass storage
          tests and includes a working implementation of the NuttShell (<a href="NuttShell.html">NSH</a>).
      </p>
      <p>
          Support for <a href="NuttXDemandPaging.html">on-demand paging</a> has been developed for the EA3131.
      That support would all execute of a program in SPI FLASH by paging code sections out of SPI flash as needed.
      However, as of this writing, I have not had the opportunity to verify this new feature.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <b>NXP LPC315x</b>.
    Support for the NXP LPC315x family has been incorporated into the code base as of NuttX-6.4.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The MCU support logic is present but as of this writing has not been verified on hardware.
          Because of the high degree of compatibility between the LPC313x and LPC315x family, it
          is very likely that the support is in place (or at least very close).
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="armcortexm3"><b>ARM Cortex-M3</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S6918</b>.
      This port uses the <a href=" http://www.micromint.com/">Micromint</a> Eagle-100 development
      board with a GNU arm-elf toolchain* under either Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          The initial, release of this port was included in NuttX  version 0.4.6.
          The current port includes timer, serial console, Ethernet, SSI, and microSD support.
          There are working configurations the NuttX OS test, to run the <a href="NuttShell.html">NuttShell
          (NSH)</a>, the NuttX networking test, and the uIP web server.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S6965</b>.
      This port uses the Stellaris LM3S6965 Ethernet Evalution Kit with a GNU arm-elf toolchain*
      under either Linux or Cygwin.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          This port was released in NuttX 5.5.  
          Features are the same as with the Eagle-100 LM3S6918 described above.
          The apps/examples/ostest configuration has been successfully verified and an
          NSH configuration with telnet support is available.
          MMC/SD and Networking support was not been thoroughly verified:
          Current development efforts are focused on porting the NuttX window system (NX)
          to work with the Evaluation Kits OLED display.
      </p>
      <p><small>
         <b>NOTE</b>: As it is configured now, you MUST have a network connected.
         Otherwise, the NSH prompt will not come up because the Ethernet
         driver is waiting for the network to come up.
      </small></p>
      <p>
        <b>Development Environments:</b> See the Eagle-100 LM3S6918 above.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S8962</b>.
      This port uses the Stellaris EKC-LM3S8962 Ethernet+CAN Evalution Kit with a GNU arm-elf toolchain*
      under either Linux or Cygwin.
      Contributed by Larry Arnold.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
          This port was released in NuttX 5.10. 
          Features are the same as with the Eagle-100 LM3S6918 described above.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Luminary/TI LM3S9B96</b>.
      Header file support was contributed by Tiago Maluta for this part.
      However, no complete board support configuration is available as of this writing.
    </p>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>STMicro STM32F103x</b>.
      Support for three MCUs and two board configurations are available.
      MCU support includes: STM32F103ZET6, STM32F103RET6, and STM32F107VC.
      Board support includes:
    </p>
    <ol>
      <li>
        This port uses the <a href=" http://www.st.com/">STMicro</a> STM3210E-EVAL development board that
        features the STM32F103ZET6 MCU.
      </li>
      <li>
        ISOTEL NetClamps VSN V1.2 ready2go sensor network platform based on the
        STMicro STM32F103RET6.  Contributed by Uros Platise.
      </li>
    </ol>
    <p>
      These ports uses a GNU arm-elf toolchain* under either Linux or Cygwin (with native Windows GNU
      tools or Cygwin-based GNU tools).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
      </p>
      <ul>
        <li>
          The basic STM32 port was released in NuttX version 0.4.12. The basic port includes boot-up
          logic, interrupt driven serial console, and system timer interrupts.
          The 0.4.13 release added support for SPI, serial FLASH, and USB device.;
          The 4.14 release added support for buttons and SDIO-based MMC/SD and verifed DMA support.
          Verified configurations are available for NuttX OS test, the NuttShell (NSH) example,
          the USB serial device class, and the USB mass storage device class example.
        </li>
        <li>
          Support for the NetClamps VSN was included in version 5.18 of NuttX.
        </li>
      </ul>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (RIDE7, CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/project/showfiles.php?group_id=189573&package_id=224585">buildroot</a>
        package.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Atmel AT91SAM3U</b>.
      This port uses the <a href="http://www.atmel.com/">Atmel</a> SAM3U-EK
      development board that features the AT91SAM3U4E MCU.
      This port uses a GNU arm-elf or arm-eabi toolchain* under either Linux or Cygwin (with native Windows GNU
      tools or Cygwin-based GNU tools).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        The basic SAM3U-EK port was released in NuttX version 5.1. The basic port includes boot-up
        logic, interrupt driven serial console, and system timer interrupts.
        That release passes the NuttX OS test and is proven to have a valid OS implementation.
        A configuration to support the NuttShell is also included.
        NuttX version 5.4 adds support for the HX8347 LCD on the SAM3U-EK board.
        This LCD support includes an example using the
        <a href=" http://www.nuttx.org/NXGraphicsSubsystem.html">NX graphics system</a>.
      </p>
      <p>
        Subsequent NuttX releases will extend this port and add support for SDIO-based SD cards and
        USB device (and possible LCD support).
        These extensions may or may not happen by the Nuttx 5.5 release as my plate is kind of full now.
      </p>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery or devkitARM).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a>
        package.
      </p>
     </ul>
   </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>NXP LPC1766 and LPC1768</b>.
      Configurations are available for three boards:
      <ul>
        <li>
          The Nucleus 2G board from <a href="http://www.2g-eng.com/">2G Engineering</a> (LPC1768),
        </li>
        <li>
          The mbed board from <a href="http://mbed.org">mbed.org</a> (LPC1768, Contributed by Dave Marples), and
        </li>
        <li>
          The LPC1766-sTK board from <a href="http://www.olimex.com/">Olimex</a> (LPC1766).
        </li>
        <li>
          The Embedded Artists base board with NXP LPCXpresso LPC1768.
        </li>
      </ul>
    </p>
    <p>
      The Nucleus 2G boar, the mbed board, and the LPCXpresso all feature the NXP LPC1768 MCU;
      the Olimex LPC1766-STK board features an LPC1766.
      All use a GNU arm-elf or arm-eabi toolchain* under either Linux or Cygwin (with native Windows GNU tools or Cygwin-based GNU tools).
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        The following summarizes the features that has been developed and verified on individual LPC17xx-based boards.
        These features should, however, be common and available for all LPC17xx-based boards.
      </p>
      <ol>
        <li>
        <p><b>Nucleus2G LPC1768</b></p>
        <ul>
          <li>
            Some initial files for the LPC17xx family were released in NuttX 5.6, but
          </li>
          <li>
            The first functional release for the NXP LPC1768/Nucleus2G occured with NuttX 5.7 with
            Some additional enhancements through NuttX-5.9.
          </li>
        </ul>
      </p>
      <p>
        That initial, 5.6, basic release included <i>timer</i> interrupts and a <i>serial console</i> and was
        verified using the NuttX OS test (<code>apps/examples/ostest</code>).
        Configurations available include include a verified NuttShell (NSH) configuration
        (see the <a href="http://www.nuttx.org/NuttShell.html">NSH User Guide</a>).
        The NSH configuration supports the Nucleus2G's microSD slot and additional configurations
        are available to exercise the the USB serial and USB mass storage devices.
        However, due to some technical reasons, neither the SPI nor the USB device drivers are fully verified.
        (Although they have since been verfiied on other platforms; this needs to be revisited on the Nucleus2G).
      </p>
      </li>
      <li>
        <p><b>mbed LPC1768</b></p>
        <ul>
          <li>
            Support for the mbed board was contributed by Dave Marples and released in NuttX-5.11.
          </li>
        </ul>
      </p>
      <p>
        This port includes a NuttX OS test configuration (see <code>apps/examples/ostest</code>).
      </p>
      </li>
      <li>
        <p><b>Olimex LPC1766-STK</b></p>
        <ul>
          <li>
            Support for that Olimex-LPC1766-STK board was added to NuttX 5.13.
          </li>
          <li>
            The NuttX-5.14 release extended that support with an <i>Ethernet driver</i>.
          </li>
          <li>
            The NuttX-5.15 release further extended the support with a functional <i>USB device driver</i> and <i>SPI-based micro-SD</i>.
          </li>
          <li>
            The NuttX-5.16 release added a functional <i>USB host controller driver</i> and <i>USB host mass storage class driver</i>.
          </li>
          <li>
            The NuttX-5.17 released added support for low-speed USB devicers, interrupt endpoints, and a <i>USB host HID keyboard class driver</i>.
          </li>
        </ul>
      </p>
      <ul><p>
        Verified configurations are now available for the NuttX OS test,
        for the NuttShell with networking and microSD support(NSH, see the <a href="ttp://www.nuttx.org/NuttShell.html">NSH User Guide</a>),
        for the NuttX network test, for the <a href="http://acme.com/software/thttpd">THTTPD</a> webserver,
        for USB serial deive and USB storage devices examples, and for the USB host HID keyboard driver.
        Support for the USB host mass storage device can optionally be configured for the NSH example.
        A driver for the <i>Nokia 6100 LCD</i> and an NX graphics configuration for the Olimex LPC1766-STK have been added.
        However, neither the LCD driver nor the NX configuration have been verified as of the the NuttX-5.17 release.
      </p></ul>
      </li>
      <li>
        <p><b>Embedded Artists base board with NXP LPCXpresso LPC1768</b></p>
        <ul>
           An fully verified board configuration is included in NuttX-6.2.
           The Code Red toolchain is supported under either Linux or Windows.
           Verifed configurations include DHCPD, the NuttShell (NSH), NuttX graphis (NX), the NuttX OS test, THTTPD, and USB mass storage device.
        </ul>
      </li>
      </ol>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin
        with Windows native toolchain (CodeSourcery devkitARM or Code Red).  A DIY toolchain for Linux
        or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a>
        package.
      </p>
   </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="atmelavr"><b>Atmel AVR</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>SoC Robotics ATMega128</b>.
      This port of NuttX to the Amber Web Server from <a href="http://www.soc-robotics.com/index.htm">SoC Robotics</a>
      is partially completed.
      The Amber Web Server is based on an Atmel ATMega128.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         Work on this port has stalled due to toolchain issues.  Complete, but untested
         code for this port appears in the NuttX 6.5 release.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Micropendous 3 AT9USB64x</b> and <b>AT9USB6128x</b>.
      This port of NuttX to the Opendous Micropendous 3 board. The Micropendous3 is
      may be populated with an AT90USB646, 647, 1286, or 1287.  I have only the AT90USB647
      version for testing.  This version have very limited memory resources: 64Kb of
      FLASH and 4Kb of SRAM.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         The basic port was released in NuttX-6.5.  This basic port consists only of
         a &quot;Hello, World!!&quot; example that demonstrates initialization of the OS,
         creation of a simple task, and serial console output.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PJRC Teensy++ 2.0 AT9USB1286</b>.
      This is a port of NuttX to the PJRC Teensy++ 2.0 board.
      This board was developed by <a href="http://pjrc.com/teensy/">PJRC</a>.
      The Teensy++ 2.0 is based on an Atmel AT90USB1286 MCU.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         The basic port was released in NuttX-6.5.  This basic port consists of
         a &quot;Hello, World!!&quot; example that demonstrates initialization of the OS,
         creation of a simple task, and serial console output as well as a somewhat
         simplified NuttShell (NSH) configuration (see the
         <a href="http://www.nuttx.org/NuttShell.html">NSH User Guide</a>).
      </p>
      <p>
         An SPI driver and a USB device driver exist for the AT90USB as well
         as a USB mass storage configureation.  However, this configuration is not
         fully debugged as of the NuttX-6.5 release.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p><b>AVR-Specific Issues</b>.
      The basic AVR port is solid and biggest issue for using AVR is its tiny SRAM memory and its Harvard architecture.
      Because of the Harvard architecture, constant data that resides to flash is inaccessible using &quot;normal&quot; memory reads and writes (only SRAM data can be accessed &quot;normally&quot;).
      Special AVR instructions are available for accessing data in FLASH, but these have not been integrated into the normal, general purpose OS.
    </p>
    <p>
      Most NuttX test applications are console-oriented with lots of strings used for printf and debug output.
      These strings are all stored in SRAM now due to these data accessing issues and even the smallest console-oriented applications can quickly fill a 4-8Kb memory.
      So, in order for the AVR port to be useful, one of two things would need to be done:
    </p>
    <ol>
      <li>
        Don't use console applications that required lots of strings.
        The basic AVR port is solid and your typical deeply embedded application should work fine.
        Or,
      </li>
      <li>
        Create a special version of printf that knows how to access strings that reside in FLASH (or EEPROM).
      </li>
    </ol>
</tr>
<tr>
  <td><br></td>
  <td>
      <p>
        <b>Development Environments:</b>
        1) Linux with native Linux GNU toolchain, 2) Cygwin with Cygwin GNU toolchain, or 3) Cygwin with Windows native toolchain. 
        All testing, however, has been performed using the Nuttx DIY toolchain for Linux  or Cygwin is provided by the NuttX
        <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a> package.
        As a result, that toolchain is recommended.
      </p>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><br></td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="atmelavr32"><b>Atmel AVR32</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>AV32DEV1</b>.
      This port uses the www.mcuzone.com AVRDEV1 board based on the Atmel AT32UC3B0256 MCU.
      This port requires a special GNU avr32 toolchain available from atmel.com website.
      This is a windows native toolchain and so can be used only under Cygwin on Windows.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         This port is has completed all basic development, but there is more that needs to be done.
         All code is complete for the basic NuttX port including header files for all AT32UC3* peripherals.
         The untested AVR32 code was present in the 5.12 release of NuttX.
         Since then, the basic RTOS port has solidified:
      </p>
      <ul>
        <li>
          The port successfully passes the NuttX OS test (apps/examples/ostest).
        </li>
        <li>
          A NuttShell (NSH) configuration is in place (see the <a href="http://www.nuttx.org/NuttShell.html">NSH User Guide</a>).
          Testing of that configuration has been postponed (because it got bumped by the Olimex LPC1766-STK port).
          Current Status: I think I have a hardware problem with my serial port setup.
          There is a good chance that the NSH port is complete and functional, but I am not yet able to demonstrate that.
          At present, I get nothing coming in the serial RXD line (probably because the pins are configured wrong or I have the MAX232 connected wrong).
        </li>
      </ul>
      <p>
        The basic, port (including the verified apps/examples/ostest configuration) was be released in NuttX-5.13.
        A complete port will include drivers for additional AVR32 UC3 devices -- like SPI and USB --- and will be available in a later release,
        time permitting.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="m68hcs12"><b>Freescale M68HCS12</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>MC9S12NE64</b>.
      Support for the MC9S12NE64 MCU and two boards are included:
    </p>
    <ul>
      <li>
        The Freescale DEMO9S12NE64 Evaluation Board, and
      </li>
      <li>
        The Future Electronics Group NE64 /PoE Badge board.
      </li>
    </ul>
    <p>
      Both use a GNU arm-elf toolchain* under Linux or Cygwin.
      The NuttX <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a> provides a properly patched GCC 3.4.4 toolchain that is highly optimized for the m9s12x family.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         Coding is complete for the MC9S12NE64 and for the NE64 Badge board.
         However, testing has not yet begun due to issues with BDMs, Code Warrior, and
         the paging in the build process.
         Progress is slow, but I hope to see a fully verified MC9S12NE64 port in the near future.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="8052"><b>Intel 8052 Microcontroller</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PJRC 87C52 Development Board</b>.
      This port uses the <a href="http://www.pjrc.com/">PJRC</a> 87C52 development system
      and the <a href="http://sdcc.sourceforge.net/">SDCC</a> toolchain under Linux or Cygwin.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
        This port is complete but not stable with timer interrupts enabled.
        There seems to be some issue when the stack pointer enters into the indirect IRAM
        address space during interrupt handling.
        This architecture has not been built in some time will likely have some compilation
        problems because of SDCC compiler differences.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="80x86"><b>Intel 80x86</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>QEMU/Bifferboard i486</b>.
      This port uses the <a href="http://wiki.qemu.org/Main_Page">QEMU</a> i486 and the native
      Linux, Cywgin, MinGW the GCC toolchain under Linux or Cygwin.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         The basic port was code-complete in NuttX-5.19 and verifed in NuttX-6.0.
         The port was verified using the OS and NuttShell (NSH) examples under QEMU.
         The port is reported to be functional on the <a href="http://bifferos.bizhat.com">Bifferboard</a> as well.
         This is a great, stable starting point for anyone interest in fleshing out the x86 port!
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>RGMP</b>.
      RGMP stands for RTOS and GPOS on Multi-Processor.
      RGMP is a project for  running GPOS and RTOS simultaneously on multi-processor platforms
      You can port your favorite RTOS to RGMP together with an unmodified Linux to form a hybrid operating system.
      This makes your application able to use both RTOS and GPOS features.
    </p>
    <p>
      See the <a href="http://rgmp.sourceforge.net/wiki/index.php/Main_Page">RGMP Wiki</a> for further information about RGMP.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
         This initial port of NuttX to RGMP was provided in NuttX-6.3.
         This initial RGP port provides only minimal driver support and does not use the native NuttX interrupt system.
         This is a great, stable starting point for anyone interest in working with NuttX under RGMP!
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="pic32mips"><b>MicroChip PIC32 (MIPS)</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PIC32MX460F512L</b>.
      A port of NuttX to the PIC32MX460F512L is underway.
      This port uses the PIC32MX board from PCB Logic Design Co.
      The board is a very simple -- little more than a carrier for the PIC32 MCU plus voltage regulation, debug interface, and an OTG connector.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
       This port is code complete and has begun testing.
       Testing is, unfortunately, delayed until I obtain some additional test equipment
       (you can't use PICkit 2 with the PIC32; you need PICkit 3.  And, to make things worse,
       my PICKit3 just hangs when I try to debug).
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>PIC32MX440F512H</b>.
        This port uses the &quot;Advanced USB Storage Demo Board,&quot; Model DB-DP11215, from <a href="http://www.sureelectronics.net">Sure Electronics</a>.
        This board features the MicroChip PIC32MX440F512H.  See the <a href="http://www.sureelectronics.net/goods.php?id=1168">Sure website</a> for further    information about the DB-DP11215 board.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
       This port is code complete and has begun testing.
       I hope to use the on-board LEDs to work around the debug problems with the PCL Logic board (see above).
       Update: Work on this board has stalled due to higher priority tasks.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Development Environment:</b>
      These ports uses the <i>LITE</i> version of the PIC32MX toolchain available
      for download from the <a href="http://www.microchip.com">MicroChip</a> website.
    </p>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><br></td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="superh"><b>Renesas/Hitachi SuperH</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>SH-1 SH7032</b>.
      This port uses the Hitachi SH-1 Low-Cost Evaluation Board (SH1_LCEVB1), US7032EVB,
      with a GNU arm-elf toolchain* under Linux or Cygwin.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
        This port is available as of release 0.3.18 of NuttX.  The port is basically complete
        and many examples run correctly.  However, there are remaining instabilities that
        make the port un-usable.  The nature of these is not understood; the behavior is
        that certain SH-1 instructions stop working as advertised.  This could be a silicon
        problem, some pipeline issue that is not handled properly by the gcc 3.4.5 toolchain
        (which has very limit SH-1 support to begin with), or perhaps with the CMON debugger.
        At any rate, I have exhausted all of the energy that I am willing to put into this cool
        old processor for the time being.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="m16c"><b>Renesas M16C/26</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Renesas M16C/26 Microncontroller</b>.
      This port uses the Renesas SKP16C26 Starter kit and the GNU M32C toolchain. 
      The development environment is either Linux or Cygwin under WinXP.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Initial source files released in nuttx-0.4.2.
        At this point, the port has not been integrated;    the target cannot be built
        because the GNU <code>m16c-elf-ld</code> link fails with  the following message:
      </p>
      <ul>
      <code>m32c-elf-ld: BFD (GNU Binutils) 2.19 assertion fail /home/Owner/projects/nuttx/buildroot/toolchain_build_m32c/binutils-2.19/bfd/elf32-m32c.c:482</code>
      </ul>
      <p>Where the reference line is:</p>
      <ul><pre>
/* If the symbol is out of range for a 16-bit address,
   we must have allocated a plt entry.  */
BFD_ASSERT (*plt_offset != (bfd_vma) -1);
</pre></ul>
      <p>
        No workaround is known at this time.  This is a show stopper for M16C for
        the time being.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogz16f"><b>Zilog Z16F</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Zilog z16f Microncontroller</b>.
      This port use the Zilog z16f2800100zcog development kit and the Zilog
      ZDS-II Windows command line tools.
      The development environment is Cygwin under WinXP.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        The initial release of support for the z16f was made available in NuttX version 0.3.7.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogez80acclaim"><b>Zilog eZ80 Acclaim!</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Zilog eZ80Acclaim! Microncontroller</b>.
      There are two eZ80Acclaim! ports:
    </p>
    <ul>
      <li>One uses the ZiLOG ez80f0910200kitg development kit, and
      <li>The other uses the ZiLOG ez80f0910200zcog-d development kit.
    </ul>
    <p>
      Both boards are based on the eZ80F091 part and both use the Zilog ZDS-II
      Windows command line tools.
      The development environment is Cygwin under WinXP.
    </p>
    <ul>
      <p>
        <b>STATUS:</b>
        Integration and testing of NuttX on the  ZiLOG ez80f0910200zcog-d is complete.
        The first integrated version was released in NuttX version 0.4.2 (with important early bugfixes
        in 0.4.3 and 0.4.4).
        As of this writing, that port provides basic board support with a serial console, SPI, and eZ80F91 EMAC driver.
      </p>
    </ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogz8encore"><b>Zilog Z8Encore!</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Zilog Z8Encore! Microncontroller</b>.
      This port uses the either:
    </p>
    <ul>
      <li>Zilog z8encore000zco development kit, Z8F6403 part, or</li>
      <li>Zilog z8f64200100kit development kit, Z8F6423 part</li>
    </ul>
    <p>
      and the Zilog ZDS-II Windows command line tools.
      The development environment is Cygwin under WinXP.
    </p>
    <ul>
       <p>
         <b>STATUS:</b>
         This release has been verified only on the ZiLOG ZDS-II Z8Encore! chip simulation
         as of nuttx-0.3.9.
       </p>
     <ul>
  </td>
</tr>
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <a name="zilogz80"><b>Zilog Z80</b>.</a>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Z80 Instruction Set Simulator</b>.
      This port uses the <a href="http://sdcc.sourceforge.net/">SDCC</a> toolchain
      under Linux or Cygwin (verified using version 2.6.0).
      This port has been verified using only a Z80 instruction simulator.
      That simulator can be found in the NuttX SVN
      <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/misc/sims/z80sim/">here</a>.
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
        This port is complete and stable to the extent that it can be tested
        using an instruction set simulator.
      </p>
    <ul>
  </td>
</tr>
<tr>
  <td><br></td>
  <td><hr></td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>XTRS: TRS-80 Model I/III/4/4P Emulator for Unix</b>.
      A very similar Z80 port is available for <a href="http://www.tim-mann.org/xtrs.html">XTRS</a>,
      the TRS-80 Model I/III/4/4P Emulator for Unix.
      That port also uses the <a href="http://sdcc.sourceforge.net/">SDCC</a> toolchain
      under Linux or Cygwin (verified using version 2.6.0).
    </p>
    <ul>
      <p>
       <b>STATUS:</b>
       Basically the same as for the Z80 instruction set simulator.
       This port was contributed by Jacques Pelletier.
      </p>
    <ul>
  </td>
</tr>
</table></center>

<blockquote>* A highly modified <a href="http://buildroot.uclibc.org/">buildroot</a>
is available that may be used to build a NuttX-compatible ELF toolchain under
Linux or Cygwin.  Configurations are available in that buildroot to support ARM, Cortex-M3,
avr, m68k, m68hc11, m68hc12, m9s12, blackfin, m32c, h8, and SuperH ports.</blockquote>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="environments"><h1>Development Environments</h1></a>
  </td>
  </tr>
</table>

<center><table width="90%">
<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Linux + GNU <code>make</code> + GCC/binutils</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      The is the most natural development environment for NuttX.
      Any version of the GCC/binutils toolchain may be used.
      There is a  highly modified <a href="http://buildroot.uclibc.org/">buildroot</a>
      available for download from the
      <a href="http://sourceforge.net/project/showfiles.php?group_id=189573">NuttX SourceForge</a>
      page.
      This download may be used to build a NuttX-compatible ELF toolchain under Linux or Cygwin.
      That toolchain will support ARM, m68k, m68hc11, m68hc12, and SuperH ports.
      The buildroot SVN may be accessed in the 
      <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/misc/buildroot/">NuttX SVN</a>.
    </p>
   </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Linux + GNU <code>make</code> + SDCC</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      Also very usable is the Linux environment using the 
      <a href="http://sdcc.sourceforge.net/">SDCC</a> compiler.
      The SDCC compiler provides support for the 8051/2, z80, hc08, and other microcontrollers.
      The SDCC-based logic is less well exercised and you will likely find some compilation
      issues if you use parts of NuttX with SDCC that have not been well-tested.
    </p>
   </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Cygwin + GNU <code>make</code> + GCC/binutils</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      This combination works well too.
      It works just as well as the native Linux environment except
      that compilation and build times are a little longer.
      The custom NuttX <a href="http://sourceforge.net/projects/nuttx/files/buildroot/">buildroot</a> referenced above may be build in
      the Cygwin environment as well.
    </p>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Cygwin + GNU <code>make</code> + SDCC</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
       I have never tried this combination, but it would probably work just fine.
    </p>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Cygwin + GNU <code>make</code> + Windows Native Toolchain</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      This is a tougher environment.
      In this case, the Windows native toolchain is unaware of the
      Cygwin <i>sandbox</i> and, instead, operates in the native Windows environment.
      The primary difficulties with this are:
    </p>
    <ul>
      <li>
        <b>Paths</b>.
        Full paths for the native toolchain must follow Windows standards.
        For example, the path <code>/home/my\ name/nuttx/include</code> my have to be
        converted to something like <code>'C:\cygwin\home\my name\nuttx\include'</code>
        to be usable by the toolchain.
      </li>
      <p>
        Fortunately, this conversion is done simply using the <code>cygpath</code> utility.
      </p>
      <li>
        <b>Symbolic Links</b>
        NuttX depends on symbolic links to install platform-specific directories in the build system.
        On Linux, true symbolic links are used.
        On Cygwin, emulated symbolic links are used.
        Unfortunately, for native Windows applications that operate outside of the
        Cygwin <i>sandbox</i>, these symbolic links cannot be used.
      </li>
      <p>
        The NuttX make system works around this limitation by copying the platform
        specific directories in place.
        These copied directories make work a little more complex, but otherwise work well.
      </p>
      <p><small>
        NOTE: In this environment, it should be possible to use the NTFS <code>mklink</code> command to create links.
        This should only require a minor modification to the build scripts (see <code>tools/winlink.sh</code> script).
      </small></p>
      <li>
        <b>Dependencies</b>
        NuttX uses the GCC compiler's <code>-M</code> option to generate make dependencies.  These
        dependencies are retained in files called <code>Make.deps</code> throughout the system.
        For compilers other than GCC, there is no support for making dependencies in this way.
        For Windows native GCC compilers, the generated dependencies are windows paths and not
        directly usable in the Cygwin make.  By default, dependencies are surpressed for these
        compilers as well.
      </li>
      <p><small>
        NOTE: dependencies are suppress by setting the make variable <code>MKDEPS</code> to point
        to the do-nothing dependency script, <code>tools/mknulldeps.sh</code>.
        Dependencies can be enabled for the Windows native GCC compilers by setting
        <code>MKDEPS</code> to point to <code>$(TOPDIR)/tools/mkdeps.sh --winpaths $(TOPDIR)</code>.
      </small></p>
    </ul>
    <p>
      <b>Supported Windows Native Toolchains</b>.
      At present, only the Zilog Z16F, z8Encore, and eZ80Acclaim ports use a non-GCC native Windows
      toolchain(the Zilog ZDS-II toolchain).
      Support for Windows native GCC toolchains (CodeSourcery and devkitARM) is currently implemented
      for the NXP LPC214x, STMicro STR71x, and Luminary LMS6918 ARM ports.
      (but could easily be extended to any other GCC-based platform with a small effort).
    </p>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Wine + GNU <code>make</code> + Windows Native Toolchain</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      I've never tried this one, but I off the following reported by an ez80 user using the ZiLOG ZDS-II Windows-native toolchain:
    </p>
    <blockquote>
      <p>
         &quot;I've installed ZDS-II 5.1.1 (IDE for ez80-based boards) on wine (windows emulator for UNIX) and to my surprise, not many changes were needed to make SVN snapshot of Nuttx buildable...
         I've tried nsh profile and build process completed successfully.
         One remark is necessary: Nuttx makefiles for ez80 are referencing <code>cygpath</code> utility.
         Wine provides similar thing called <code>winepath</code> which is compatible and offers compatible syntax.
         To use that, <code>winepath</code> (which itself is a shell script) has to be copied as <code>cygpath</code> somewhere in <code>$PATH</code>, and edited as in following patch:
       </p>
       <ul><pre>
# diff -u `which winepath` `which cygpath`
--- /usr/bin/winepath 2011-05-02 16:00:40.000000000 +0200
+++ /usr/bin/cygpath 2011-06-22 20:57:27.199351255 +0200
@@ -20,7 +20,7 @@
#

# determine the app Winelib library name
-appname=`basename "$0" .exe`.exe
+appname=winepath.exe

# first try explicit WINELOADER
if [ -x "$WINELOADER" ]; then exec "$WINELOADER" "$appname" "$@"; fi
</pre></ul>
      <p>
        &quot;Better solution would be replacing all <code>cygpath</code> references in  <code>Makefiles </code> with  <code>$(CONVPATH)</code> (or  <code>${CONVPATH}</code> in shell scripts) and setting <code>CONVPATH</code> to  <code>cygpath</code> or  <code>winepath</code> regarding to currently used environment.
      </p>
    </blockquote>
  </td>
</tr>

<tr>
  <td valign="top"><img height="20" width="20" src="favicon.ico"></td>
  <td bgcolor="#5eaee1">
    <b>Other Environments?
    Windows Native <code>make</code> + Windows Native Toolchain?</b>
  </td>
</tr>
<tr>
  <td><br></td>
  <td>
    <p>
      <b>Environment Dependencies</b>.
      The primary environmental dependency of NuttX are (1) GNU make,
      (2) bash scripting, and (3) Linux utilities (such as cat, sed, etc.).
      If you have other platforms that support GNU make or make
      utilities that are compatible with GNU make, then it is very
      likely that NuttX would work in that environment as well (with some
      porting effort). If GNU make is not supported, then some significant
      modification of the Make system would be required.
    </p>
    <p>
     <b>GNUWin32</b>.
      For example, with suitable make system changes, it should be possible to
      use native GNU tools (such as those from
      <a href="http://sourceforge.net/projects/gnuwin32/">GNUWin32</a>)
      to build NuttX.
      However, that environment has not been used as of this writing.
   </p>
      <p><small>
        NOTE: One of the members on the <a href="http://tech.groups.yahoo.com/group/nuttx/">NuttX forum</a>
        reported that they successful built NuttX using such a GNUWin32-based, Windows native environment.
        They reported that the only necessary change was to the use the NTFS mklink command to create links
        (see <code>tools/winlink.sh</code> script).
      </small></p>
  </td>
</tr>
</table></center>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="footprint"><h1>Memory Footprint</h1></a>
  </td>
  </tr>
</table>

<ul>
<p><b>C5471 (ARM7)</b>
  The build for this ARM7 target that includes most of the OS features and
  a broad range of OS tests.  The size of this executable as given by the
  Linux <tt>size</tt> command is (3/9/07):
</p>
<pre>
   text    data     bss     dec     hex filename
  53272     428    3568   57268    dfb4 nuttx
</pre>
<p><b>DM320 (ARM9)</b>
  This build for the ARM9 target includes a significant subset of OS
  features, a filesystem, Ethernet driver, full TCP/IP, UDP and (minimal)
  ICMP stacks (via uIP) and a small network test application: (11/8/07,
  configuration netconfig, apps/examples/nettest)
</p>
<pre>
   text    data     bss     dec     hex filename
  49472     296    3972   53740    d1ec nuttx
</pre>
<p>
  Another build for the ARM9 target includes a minimal OS feature
  set, Ethernet driver, full TCP/IP and (minimal) ICMP stacks, and
  a small webserver: (11/20/07, configuration uipconfig, apps/examples/uip)
</p>
<pre>
   text    data     bss     dec     hex filename
  52040      72    4148   56260    dbc4 nuttx
</pre>
<p><b>87C52</b>
  A reduced functionality OS test for the 8052 target requires only
  about 18-19Kb:
</p>
<pre>
Stack starts at: 0x21 (sp set to 0x20) with 223 bytes available.

Other memory:
   Name             Start    End      Size     Max
   ---------------- -------- -------- -------- --------
   PAGED EXT. RAM                         0      256
   EXTERNAL RAM     0x0100   0x02fd     510     7936
   ROM/EPROM/FLASH  0x2100   0x6e55   19798    24384
</pre>
</ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="licensing"><h1>Licensing</h1></a>
  </td>
  </tr>
</table>

<ul>
<p>
  NuttX is available under the highly permissive
  <a href="http://en.wikipedia.org/wiki/BSD_license">BSD license</a>.
  Other than some fine print that you agree to respect the copyright
  you should feel absolutely free to use NuttX in any environment and
  without any concern for jeopardizing any proprietary software that
  you may link with it.
</p>
</ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="history"><h1>Release History</h1></a>
  </td>
  </tr>
</table>

<ul>
<p>
   The current NuttX Change Log is available in SVN <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/nuttx/ChangeLog?view=log">here</a>.
   ChangeLog snapshots associated with the current release are available below.
</p>
</ul>

<center><table width ="80%">
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
   <td>
      <a href="ChangeLog.txt">Change Logs for All NuttX Releases</a><br>
   </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
   <td>
      <a href="#currentrelease">ChangeLog for the Current Releases</a><br>
   </td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
   <td>
      <a href="#pendingchanges">Unreleased Changes</a>
   </td>
</tr>
</table></center>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="currentrelease">ChangeLog for the Current Release</a>
  </td>
  </tr>
</table>

<ul><pre>
nuttx-6.7 2011-08-02 Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

    * Makefile:  Added a export target that will bundle up all of the NuttX
      libraries, header files, and the startup object into an export-able
      tarball.
    * arch/arm/src/lpc17xx/lpc17_can.h:  Correct some typos in the CAN
      register definitions.
    * drivers/serial/serialirq.c:  Correct an error that can occur if the
      serial RX buffer becomes full.  Data is now discarded in that case;
      before, leaving data in the hardware would cause infinite interrupts
      one most MCUs since you must read the data in order to clear the
      interrupt.
    * arch/arm/src/lpc17xx/lpc17_can.c:  Added a CAN driver contributed by
      Li Zhuoyi (Lzyy).
    * include/stddefs.h and sys/types:  Added type wchar_t.
    * fs/fat/fat_fat32dirent.c:  Move all FAT directory operations to this
      new file; Implement VFAT long file name support.
    * fs/fat/fat_fat32dirent.c:  The configuration CONFIG_FAT_LCNAMES has
      been around for some time but never tested until now.  This setting
      will mimic the NT 8.3 file name behavior:  File names or extensions 
      may be all upper or all lower case (but not mixed).  If
      CONFIG_FAT_LCNAMES is not selected, all filenames are strictly upper
      case.
    * configs/stm3210e-eval/nsh2:  Console is back on UART1; Added
      examplex/nx as an NSH &quot;built-in&quot; command as a demonstration.
    * fs/fat/fs_fat32dirent.c:  Fix an important bug in the directory
      allocation (fat_allocatedirentry()).  I looks like it could be
      initializing the wrong sectors! NOTE:  This function was in
      fs_fat32utils.c in earlier releases.
    * arch/arm/src/stm32_sdio.c: Correct an important DMA-related bug;
      SDIO transfer completion events and DMA completion eventes were
      not being coordinated correctly.
    * configs/stm3210e-eval/nsh2: Enable FAT long file name support
    * sched/sem_timedwait.c: Add the standard sem_timedwait() interface.
    * graphics/nxfonts/nxfonts_getfont.c, nxfonts_bitmap.c,
      Makefile.source, and include/nuttx/nxfonts.h: Support for multiple
      fonts included.  A new interface, nxf_getfonthandle() takes a font
      ID and returns a handle that is now used at all other font interfaces
      to specify which of the multiple fonts to use.
    * arch/arm/src/lpc17xx/lpc17_syscon.h: Fix typo (reported by Li Zhuoyi).
    * configs/stm3210e-eval/nsh2: Extended to support two new commands:
      'msconn' will connect the USB mass storage device; 'msdis' will
      disconnect the USB storage device.
    * tools/bdf-converter.c.  This C file is used to build the bdf-converter
      program.  The bdf-converter program be used to convert fonts in Bitmap
      Distribution Format (BDF) into fonts that can be used in the NX graphics
      system.
    * include/nuttx/nx:  Move all NX header files from include/nuttx to 
      include/nuttx/nx.
    * drivers/usbdev/usbdev_usbstorage.c and arch/arm/src/stm32/stm32_usbdev.c:
      Correct a memory leak when the USB mass storage driver is connected and
      then disconnected from the target.  The write requests were not being
      freed.  NOTE that the unregister logic in the STM32 needed to call
      stm32_reset() in order to return the write requests to the USB mass
      storage driver; it is possible that a similar but could exist for other
      architectures.
    * graphics/nxfonts/nxfonts_*.h:  Add serveral more new fonts
    * arch/z80/src/ez80/ez80_serial.c: Fix some errors in serial driver
      setup for UART1 (submitted by Paul Osmialowski).
    * drivers/input/tsc2007.c and include/nuttx/input/*:  Add a generic NuttX
      touchscreen interface.  Add a driver for the TI TSC2007 touchscreen
      controller.
    * graphics/nxglib/lcd and fb:  Add low level routines to set single pixels.
    * lib/math/lib_b16atan2.c:  Add a fixed precision atan2() function
    * graphics/nxglib/nxglib_splitline.c: Add logic to divide a wide line into
      trapezoidal components.
    * graphics/nxmu/nx_drawline.c, graphics/nxsu/nx_drawline.c,
      graphics/nxtk/nxtk_drawlinewindow.c, graphics/nxtk/nxtk_drawlinetoolbar.c:
      Add new line drawing interfaces (untested).

apps-6.7 2011-08-02 Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

    * apps/examples/nx and nxtext:  These examples can now be built as NSH
      &quot;built-in&quot; commands.
    * apps/examples/nxhello:  The simplest graphics example:  It just says
      &quot;Hello, World!&quot; in the center of the display. This example can also be
      built as an NSH &quot;built-in&quot; command.
    * apps/examples/nx, ntext, and nxhello:  All updated to use the new
      NuttX font interfaces.
    * apps/examples/nximage:  Another super simple  graphics example:  It just puts
      the NuttX logo in the center of the display. This example can also be
      built as an NSH &quot;built-in&quot; command.
    * apps/examples/usbstorage: Can now be built as two NSH &quot;built-in&quot; commands:
      'msconn' will connect the USB mass storage device; 'msdis' will disconnect
      the USB storage device.
    * apps/examples/nx*:  All NX header files moved from nuttx/include/nuttx to 
      nuttx/include/nuttx/nx.
    * apps/examples/usbstorage: Added instrumentation to monitor memory usage
      to check for memory leaks in the USB storage driver.
    * apps/examples/nxhello/nxhello_bkgd.c:  Fix handling of allocated glyph
      memory.

pascal-1.0 2011-05-15 Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

    * nuttx/:  The Pascal add-on module now installs and builds under the
      apps/interpreters directory.  This means that the pascal-2.1 module is
      incompatible with will all releases of NuttX prior to nuttx-6.0 where the 
      apps/ module was introduced.

buildroot-1.10 2011-05-06 &lt;spudmonkey@racsa.co.cr&gt;

    * Add patch submitted by Dimiter Georgiev to work around problems in building
      GDB 6.8 with versions of Cygwin &gt; 1.7.
    * configs/i486-defconfig-4.3.3 - Builds an i486 cross development toolchain
      using gcc 4.3.3.  Why wouldyou want such a thing?  On Linux, of course,
      such a thing is not needed because you can use the installed GCC to build
      i486 ELF binaries.  But that will not work under Cygwin!  The Cygwin
      toolchain (and probably MinGW), build DOS MZ format executables (i.e.,
      .exe files).  That is probably not usable for most NuttX targets.
      Instead, you should use this i486-elf-gcc to generate true ELF binaries
      under Cygwin.
    * Makefile - Alter copy arguments to avoid permissions problems when
      copying NuttX header files.
    * toolchain/nxflat/nxflat.mk and Makefile - Fix include paths.
    * toolchain/gcc/3.3.6 - Added a patch to fixed compilation error on Ubuntu
      9.10.
    * toolchain/nxflat/Makefile - Correct static library link order.
    * configs/arm920t-defconfig-4.3.3 - Enable support for NXFLAT tools.
    * toolchain/binutils/2.21 and toolchain/gcc/4.5.2 - Add support for GCC
      4.5.2 with binutils 2.21.
    * configs/arm920t-eabi-defconfig-4.5.2 - Add a configuration to build a
      GCC 4.5.2 EABI ARM toolchain for the ARM920t.
</pre></ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="pendingchanges">Unreleased Changes</a>
  </td>
  </tr>
</table>

<ul><pre>
nuttx-6.8 2011-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

apps-6.8 2011-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

pascal-3.1 2011-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;

buildroot-1.11 2011-xx-xx &lt;spudmonkey@racsa.co.cr&gt;
</pre></ul>

<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="TODO"><h1>Bugs, Issues, <i>Things-To-Do</i></h1></a>
  </td>
  </tr>
</table>

<ul>
<p>
   The current list of NuttX <i>Things-To-Do</i> in SVN <a href="http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/nuttx/TODO?view=log">here</a>.
   A snapshot of the <i>To-Do</i> list associated with the current release are available <a href="TODO.txt">here</a>.
</p>
</ul>
<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="documentation"><h1>Other Documentation</h1></a>
  </td>
  </tr>
</table>

<ul><table>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttxUserGuide.html">User Guide</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttxPortingGuide.html">Porting Guide</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttShell.html">NuttShell (NSH)</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttXNxFlat.html">NXFLAT</a> Binary Format</td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NXGraphicsSubsystem.html">NX Graphics Subsystem</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="NuttXDemandPaging.html">Demand Paging</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="README.html">NuttX README Files</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="ChangeLog.txt">Change Log</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="TODO.txt">To-Do List</a></td>
</tr>
<tr>
  <td valign="top" width="22"><img height="20" width="20" src="favicon.ico"></td>
  <td><a href="UsbTrace.html">USB Device Driver Tracing</a></td>
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</center></ul>

<small>
<table width ="100%">
  <tr bgcolor="#e4e4e4">
  <td>
    <a name="trademarks"><h1>Trademarks</h1></a>
  </td>
  </tr>
</table>
<ul>
  <li>ARM, ARM7 ARM7TDMI, ARM9, ARM920T, ARM926EJS Cortex-M3 are trademarks of Advanced RISC Machines, Limited.</li>
  <li>Cygwin is a trademark of Red Hat, Incorporated.</li>
  <li>Linux is a registered trademark of Linus Torvalds.</li>
  <li>Eagle-100 is a trademark of <a href=" http://www.micromint.com/">Micromint USA, LLC</a>.
  <li>LPC2148 is a trademark of NXP Semiconductors.</li>
  <li>TI is a tradename of Texas Instruments Incorporated.</li>
  <li>UNIX is a registered trademark of The Open Group.</li>
  <li>VxWorks is a registered trademark of Wind River Systems, Incorporated.</li>
  <li>ZDS, ZNEO, Z16F, Z80, and Zilog are a registered trademark of Zilog, Inc.</li>
</ul>
<p>
  NOTE: NuttX is <i>not</i> licensed to use the POSIX trademark.  NuttX uses the POSIX
  standard as a development guideline only.
</p>
</small>

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