nuttx/Documentation/NuttX.html
patacongo 9e16305afd Fix ICMP and UDP IP checksums
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2008-09-03 14:57:36 +00:00

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<html>
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<title>NuttX</title>
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<table width ="100%">
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<h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
<p>Last Updated: September 3, 2008</p>
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<hr><hr>
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<h1>Table of Contents</h1>
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<center><table width ="80%">
<tr>
<td>
<table>
<tr>
<td><img src="favicon.ico"></td>
<td>
<a href="#overview">Overview</a>.<br>
What is NuttX?
</td>
</tr>
<tr>
<td><img 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><img 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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<tr>
<td><img 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>
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<tr>
<td><img 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>
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<tr>
<td><img 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><img 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 CVS?
</td>
</tr>
<tr>
<td><img 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>
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<tr>
<td><img src="favicon.ico"></td>
<td>
<a href="#documentation">Other Documentation</a>.<br>
What other NuttX documentation is available?
</td>
</tr>
<tr>
<td><img 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></center>
<table width ="100%">
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<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%">
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<td valign="top" width="18"><img 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>
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<td valign="top" width="18"><img 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="18"><img src="favicon.ico"></td>
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<b>Highly Scalable</b>
</td>
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<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>
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<td valign="top" width="18"><img 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>
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<tr>
<td valign="top" width="18"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Real-Time</b>
</td>
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<td><br></td>
<td>
<p>
Fully pre-emptible, fixed priority and round-robin scheduling.
</p>
</tr>
<tr>
<td valign="top" width="18"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Totally Open</b>
</td>
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<tr>
<td><br></td>
<td>
<p>
Non-restrictive BSD license.
</p>
</tr>
</table></center>
<p>
<b>Feature Set</b>.
Key features of NuttX include:
<p>
<center><table width="90%">
<tr>
<td valign="top" width="18"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Standards Compliant Core Task Management</b>
</td>
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<tr>
<td><br></td>
<td>
<p>
<li>Modular, micro-kernel</li>
</p>
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<td><br></td>
<td>
<p>
<li>Fully pre-emptible.</li>
</p>
</tr>
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<td><br></td>
<td>
<p>
<li>Naturally scalable.</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.</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>
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<td><br></td>
<td>
<p>
<li>VxWorks-like task management and watchdog timers.</li>
</p>
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<td><br></td>
<td>
<p>
<li>BSD socket interface.</li>
</p>
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<td><br></td>
<td>
<p>
<li>Extensions to manage pre-emption.</li>
</p>
</tr>
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<td><br></td>
<td>
<p>
<li>Well documented in the NuttX <a href="NuttxUserGuide.html">User Guide</a>.</li>
</p>
</tr>
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<td valign="top" width="18"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>File system</b>
</td>
</tr>
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<td><br></td>
<td>
<p>
<li>Tiny in-memory, root pseudo-file-system.</li>
</p>
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<td><br></td>
<td>
<p>
<li>Supports character and block drivers.</li>
</p>
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<td><br></td>
<td>
<p>
<li>Network and serial driver architecture.</li>
</p>
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<td>
<p>
<li>Mount-able volumes. Bind mountpoint, filesystem, and block device driver.</li>
</p>
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<p>
<li>VFAT filesystem support.</li>
</p>
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<td valign="top" width="18"><img src="favicon.ico"></td>
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<b>C Library</b>
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<td><br></td>
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<p>
<li>Fully integrated into the OS.</li>
</p>
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<td valign="top" width="18"><img src="favicon.ico"></td>
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<b>Networking</b>
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<p>
<li>TCP/IP, UDP, ICMP stacks.</li>
</p>
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<td><br></td>
<td>
<p>
<li>Small footprint (based on uIP).</li>
</p>
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<td><br></td>
<td>
<p>
<li>BSD compatible socket layer.</li>
</p>
</tr>
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<td><br></td>
<td>
<p>
<li>Networking utilities.</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="18"><img 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>
</tr>
</table></center>
<table width ="100%">
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<td>
<a name="downloads"><h1>Downloads</h1></a>
</td>
</tr>
</table>
<p>
The 25th release of NuttX (nuttx-0.3.13) is available for download
from the <a href="http://sourceforge.net/project/showfiles.php?group_id=189573">SourceForge</a>
website.
The change log associated with the release is available <a href="#currentrelease">here</a>.
Unreleased changes after this release are available in CVS.
These unreleased changes are listed <a href="#pendingchanges">here</a>.
</p>
<p>
The nuttx-0.3.13 release includes some important bug fixes as well as a few new features.
Bugs fixed include:
<ul>
<li>Fixed problems with Cygwin-based console input. NSH now works with the Cygwin simulator.</li>
<li>sched_get_priority_max/min returned error on SCHED_RR.</li>
<li>Corrected detection of End-of-File in fgets().</li>
<li>Fixed an error in opendir() that could cause an assertion to fail inappropriately.</li>
<li>Corrected an error in the FAT that caused files opened for writing with O_APPEND to fail.</li>
<li>Fix error in getopt() when called with argc==1.</li>
<li>Fix error in stat() when used on the root directory.</li>
<li>Fixed a critical bug that effects the way that environment variables are shared amongst
pthreads.</li>
<li>uIP port now supports multi-threaded, concurrent socket access. So, for example, one
thread can be reading from a socket while another is writing to the socket.</li>
</ul>
</p>
<p>
New features were also added:
<ul>
<li>New OS APIs: chdir() and getcwd().</li>
<li>The Nuttx shell (NSH) has been extended in many ways:
<ul>
<li>New commands: mkfatfs, mkfifo, sleep, usleep, nice, sh, cd, and pwd commands
<li>New memory inspection commands and heap usage commands
<li>New capabilities: Execution of commands in background, execution of simple scripts,
redirection of command output, last command status ($?)
<li>Now supports if-then[-else]-fi construct
<li>and other features as noted in the ChangeLog.
</ul></li>
</ul>
</p>
<p>
As usual, any feedback about bugs or suggestions for improvement would be greatly appreciated.
</p>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="platforms"><h1>Supported Platforms</h1></a>
</td>
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</table>
<center><table width="90%">
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<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Linux User Mode</b>
</td>
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<td><br></td>
<td>
<p>
A user-mode port of NuttX to the x86 Linux platform is available.
The purpose of this port is primarily to support OS feature development.
</p>
<p>
<b>STATUS:</b>
Does not support interrupts but is otherwise fully functional.
</p>
</td>
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<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>ARM7TDMI</b>.
</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>
<p>
<b>STATUS:</b>
This port is complete, verified, and included in the initial NuttX release.
</p>
</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-eld toolchain* under Linux or Cygwin.
</p>
<p>
<b>STATUS:</b>
Initial coding of this port code complete but has not yet been verified.
</p>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>ARM926EJS</b>.
</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.
</p>
<p>
<b>STATUS:</b>
This port is complete and verified.
</p>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>8052 Microcontroller</b>
</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>
<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>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Zilog Z16F</b>
</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>
<p>
<b>STATUS:</b>
The initial release of support for the z16f was made available in NuttX version 0.3.7.
</p>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Zilog eZ80Acclaim!</b>
</td>
</tr>
<tr>
<td><br></td>
<td>
<p>
<b>Zilog eZ80Acclaim! Microncontroller</b>.
This port uses the ZiLOG ez80f0910200kitg development kit, eZ80F091 part
and the Zilog ZDS-II Windows command line tools.
The development environment is Cygwin under WinXP.
</p>
<p>
<b>STATUS:</b>
This is a work in progress. Verified ez80 support will be announced in a future NuttX release.
</p>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Zilog Z8Encore!</b>
</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>
<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>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Zilog Z80</b>
</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 CVS
<a href="http://nuttx.cvs.sourceforge.net/nuttx/misc/sims/z80sim/">here</a>.
</p>
<p>
<b>STATUS:</b>
This port is complete and stable to the extent that it can be tested
using an instruction set simulator.
</p>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Other ports</b>
</td>
</tr>
<tr>
<td><br></td>
<td>
<p>
There are partial ports for the TI TMS320DM270 and for MIPS.
</p>
</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 arm-elf toolchain under
Linux or Cygwin.</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 src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Linux + GNU make + 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 arm-elf toolchain under Linux or Cygwin.
Additional support for m68k, m68hc11, and m68hc12 is available in the
<a href="http://nuttx.cvs.sourceforge.net/nuttx/misc/buildroot/">NuttX CVS</a>.
</p>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Linux + GNU make + 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 src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Cygwin + GNU make + 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 buildroot referenced above may be build in
the Cygwin environment as well.
</p>
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Cygwin + GNU make + 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 src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Cygwin + GNU make + 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 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>
</ul>
<p>
At present, on the Zilog Z16F port uses a native Windows toolchain
(the Zilog ZDS-II toolchain).
</p.
</td>
</tr>
<tr>
<td valign="top"><img src="favicon.ico"></td>
<td bgcolor="#5eaee1">
<b>Others Environments?</b>
</td>
</tr>
<tr>
<td><br></td>
<td>
<p>
The primary environmental dependency of NuttX are (1) GNU make,
(2) bash scripting, and (3) Linux utilities (such as sed).
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>
</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, 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, 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 CVS <a href="http://nuttx.cvs.sourceforge.net/*checkout*/nuttx/nuttx/ChangeLog">here</a>.
ChangeLog snapshots associated with the current release are available below.
</p>
</ul>
<center><table width ="80%">
<tr>
<td><img src="favicon.ico"></td>
<td>
<a href="ChangeLog.txt">Change Logs for All NuttX Releases</a><br>
</td>
</tr>
<tr>
<td><img src="favicon.ico"></td>
<td>
<a href="#currentrelease">ChangeLog for Current Releases</a><br>
</td>
</tr>
<tr>
<td><img 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 Current Release</a>
</td>
</tr>
</table>
<pre><ul>
nuttx-0.3.13 2008-09-01 Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
* NSH: Added mkfatfs, mkfifo, sleep, usleep and nice commands
* Fixed problem with console input in Cygwin-based simulator; NSH now works
with simulator.
* NSH will now execute commands in background
* sched_get_priority_max/min returned error on SCHED_RR
* Removed duplicate getenv() implementation in /lib
* Correct detection of End-of-File in fgets
* NSH: Implemented sh and crude script handler
* Fix prototype of read() and write(). Need to use ssize_t and size_t, not
int and unsigned int.
* NSH now supports redirection of command output
* NSH can now use both telnet and serial front ends together
* NSH: $variable can be used for any command value
* Fixed an error in opendir() that could cause an assertion to fail
inappropriately.
* Correct an error in the FAT that caused files opened for writing with
O_APPEND to fail. The file was not being properly positioned to the
end of the file in that case.
* NSH now supports last exit status $?
* NSH now supports if-then[-else]-fi construct
* NSH now supports comments beginning with '#'
* NSH now supports commands to inspect and modify memory
* NSH cat command now supports multiple files on command line
* Add chdir() and getcwd()
* Fix error in getopt() when called with argc==1
* Fix error in stat() when used on the root directory
* NSH: Add cd and pwd commands and current working directory to all NSH
commands that refer to paths.
* Fix errors and warnings introduced into Linux sim build because of recent
Cygwin-based sim changes
* NSH: Add mem command to display heap usage
* Added telnet NSH configuration for Neuros OSD.
* Basic integration of concurrent telnet/serial NSH functional on Neuros
OSD.
* Fixed a critical bug that effects the way that environment variables are
shared amongst pthreads.
* uIP port enhance to support multi-threaded, concurrent socket access. So,
for example, one thread can be reading from a socket while another is
writing to the socket.
pascal-0.1.2 2008-02-10 Gregory Nutt <spudmonkey@racsa.co.cr>
* Add logic to build and link with the ZDS-II toolchain
use with the z16f.
* Make sure that POFF header structures are aligned
* Standardized POFF file format to big-endian
* Break up large switch statements to lower complexity
and eliminate a compiler bug
* Changes so that runtime compiles with SDCC.
buildroot-0.1.0 2007-03-09 &lt;spudmonkey@racsa.co.cr&gt
* Support for arm-elf toolchain
</pre></ul>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="pendingchanges">Unreleased Changes</a>
</td>
</tr>
</table>
<pre><ul>
nuttx-0.3.14 2008-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
* FAT FS now uses position variable in struct file. This simplifies operations
like ftell().
* fseek() needs to discard bytes buffered by ungetc().
* Corrected ftell() return value.
* Added fsetpos() and fgetpos().
* NSH: Now supports 'test' and '[' commands
* Correct error in send() timeout logic.
* Correct error in multi-threaded socket handling in send() and sendto().
Outgoing data could overwrite incoming data.
* Add support to uIP for application access to ICMP protocol stacks; Add
ping request logic.
* NSH: Add ping command
* Correct IP checksum calculation in ICMP and UDP message send logic.
pascal-0.1.3 2008-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
buildroot-0.1.1 2008-xx-xx &lt;spudmonkey@racsa.co.cr&gt
* Support for m68k-elf and m68hc11 toolchain
</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 CVS <a href="http://nuttx.cvs.sourceforge.net/*checkout*/nuttx/nuttx/TODO">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><img src="favicon.ico"></td>
<td><a href="NuttxUserGuide.html">User Guide</a></td>
</tr>
<tr>
<td><img src="favicon.ico"></td>
<td><a href="NuttxPortingGuide.html">Porting Guide</a></td>
</tr>
<tr>
<td><img src="favicon.ico"></td>
<td><a href="ChangeLog.txt">Change Log</a></td>
</tr>
<tr>
<td><img src="favicon.ico"></td>
<td><a href="TODO.txt">To-Do List</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, ARM926EJS 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>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>