diff --git a/ChangeLog b/ChangeLog
index d38eed7668309cbc152140f103c701a0fb5eaaaa..b5e50c3177fdb3fce82e189ff2ef9f37b6c9d2ac 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -316,9 +316,10 @@
* Added /dev/zero
* 'errno' is now defined to be *get_errno_ptr() with no name conflicts
* Added lseek() and fseek()
- * Integrated pascal test case on the simulation platform. Needs pascal-0.1.1.
- * Integrated pascal test case on the z16f platform. Needs pascal-0.1.2 (not
- yet released).
+ * Integrated Pascal interpreter test case on the simulation platform. Needs
+ pascal-0.1.1.
+ * Add Pascal test case on the z16f platform. Needs pascal-0.1.2 (does not
+ yet work due to some tool issues).
* C buffered I/O fixes:
- Fix fflush() return value,
- Add correct fflush behavior when the FILE argument is null.
@@ -329,6 +330,7 @@
* Pascal P-Code files are now standardized to big-endian for portability
* Fix a build problem with z80 and SDCC 2.7.0 (format of a map file changed)
(see bug 1887170)
+ * Pascal P-Code runtime now compiles with the SDCC toolchain.
diff --git a/Documentation/NuttX.html b/Documentation/NuttX.html
index 623ac7651c9da633a4c3585d008f574669e37f99..59c0189838b2dbf5903bcad7ba57028385f865e8 100644
--- a/Documentation/NuttX.html
+++ b/Documentation/NuttX.html
@@ -8,7 +8,7 @@
<tr align="center" bgcolor="#e4e4e4">
<td>
<h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
- <p>Last Updated: February 5, 2008</p>
+ <p>Last Updated: February 7, 2008</p>
</td>
</tr>
</table>
@@ -974,9 +974,10 @@ nuttx-0.3.8 2008-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
* Added /dev/zero
* 'errno' is now defined to be *get_errno_ptr() with no name conflicts
* Added lseek() and fseek()
- * Integrated pascal test case on the simulation platform. Needs pascal-0.1.1.
- * Integrated pascal test case on the z16f platform. Needs pascal-0.1.2 (not
- yet released).
+ * Integrated Pascal interpreter test case on the simulation platform. Needs
+ pascal-0.1.1.
+ * Add Pascal test case on the z16f platform. Needs pascal-0.1.2 (does not
+ yet work due to some tool issues).
* C buffered I/O fixes:
- Fix fflush() return value,
- Add correct fflush behavior when the FILE argument is null.
@@ -985,8 +986,9 @@ nuttx-0.3.8 2008-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
- When read data is flushed, reposition the file pointer to account for
buffered, but unreand data
* Pascal P-Code files are now standardized to big-endian for portability
- * Fix a build problem with z80 and SDCC 2.7.0 (format of a map file changed).
+ * Fix a build problem with z80 and SDCC 2.7.0 (format of a map file changed)
(see bug 1887170)
+ * Pascal P-Code runtime now compiles with the SDCC toolchain.
pascal-0.1.2 2008-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
diff --git a/Documentation/NuttxPortingGuide.html b/Documentation/NuttxPortingGuide.html
index 9ae720862ca0690396ec7b728ab016d09cb0edc7..3f6a84e3912209a43b3362f7857e6b88edab350b 100644
--- a/Documentation/NuttxPortingGuide.html
+++ b/Documentation/NuttxPortingGuide.html
@@ -16,7 +16,7 @@
</b></big>
<p><small>by</small></p>
<p>Gregory Nutt</p>
- <p><small>Last Update: January 10, 2008</small></p>
+ <p><small>Last Update: February 7, 2008</small></p>
</center>
<center><h1>Table of Contents</h1></center>
@@ -36,7 +36,7 @@
<li><a href="#summaryofconfigfiles">2.3.2 Summary of Files</a></li>
<ul>
<li><a href="#boardlogic">2.3.2.1 Board Specific Logic</a></li>
- <li><a href="#boardconfigfiles">2.3.2.2 Board Specific Configuration Files</a></li>
+ <li><a href="#boardconfigsubdirs">2.3.2.2 Board Specific Configuration Sub-Directories</a></li>
</ul>
<li><a href="#supportedboards">2.3.3 Supported Boards</a></li>
</ul>
@@ -90,13 +90,13 @@
</ul>
<li><a href="#NxFileSystem">5.0 NuttX File System</a></li>
<li><a href="#apndxconfigs">Appendix A: NuttX Configuration Settings</a></li>
-
+<li><a href="#apndxtrademarks">Appendix B: Trademarks</a></li>
<hr>
<h1>1.0 <a name="Introduction">Introduction</a></h1>
<p><b>Overview</b>
This document provides and overview of the NuttX build and configuration
- logic and provides hints for the incorporation of new processor/board archectures
+ logic and provides hints for the incorporation of new processor/board architectures
into the build.
</p>
<p>
@@ -132,7 +132,7 @@
| | | `-- <i>(chip-specific source files)</i>
| | |--<i><other-chips></i>/
| | `-- <i>(architecture-specific source files)</i>
-| `-- <i><other-architectures></i>/
+| `-- <i><other-architecture directories></i>/
|-- <a href="#DirStructConfigs">configs</a>/
| |-- <i><board-name></i>/
| | |-- include/
@@ -140,8 +140,10 @@
| | |-- src/
| | | |-- Makefile
| | | `-- <i>(board-specific source files)</i>
-| | `-- <i>(board-specific configuration files)</i>
-| `-- <i><other-boards></i>/
+| | |---<i><config1-dir></i>/
+| | | `-- <i>(board-specific/configuration-specific files)</i>
+| | `---<i>(other board-specific configuration sub-directories)</i>/
+| `-- <i><(other board directories)></i>/
|-- <a href="#DirStructDrivers">drivers</a>/
| |-- Makefile
| `-- <i>(common driver source files)</i>
@@ -226,14 +228,14 @@
</p>
</li>
<li>
- <i>Board specific files</i>.
+ <i>Board specific configurations</i>.
In order to be usable, the chip must be contained in a board environment.
The board configuration defines additional properties of the board including such things as
peripheral LEDs, external peripherals (such as network, USB, etc.).
<p>
These board-specific configuration files can be found in the
<code>configs/</code><i><board-name></i><code>/</code> sub-directories and are discussed
- in a a paragraph <a href="#configsdirectorystructure">below</a>.
+ in a paragraph <a href="#configsdirectorystructure">below</a>.
</p>
</li>
</ul>
@@ -251,8 +253,8 @@
This directory contains several sub-directories, each containing
architecture-specific logic.
The task of porting NuttX to a new processor consists of
- add a new sudirectory under <code>arch/</code> containing logic specific
- to the new architecuture.
+ add a new subdirectory under <code>arch/</code> containing logic specific
+ to the new architecture.
The complete board port in is defined by the architecture-specific code in this
directory (plus the board-specific configurations in the <code>config/</code>
subdirectory).
@@ -468,15 +470,24 @@
provide a subdirectory <board-name> under <code>configs/</code> with the following characteristics:
</p>
<ul><pre>
+ |-- Make.defs
+ |-- defconfig
+ `-- setenv.sh
<i><board-name></i>
|-- include/
| `-- <i>(board-specific header files)</i>
|-- src/
| |-- Makefile
| `-- <i>(board-specific source files)</i>
- |-- Make.defs
- |-- defconfig
- `-- setenv.sh
+ |-- <i><config1-dir></i>
+ | |-- Make.defs
+ | |-- defconfig
+ | `-- setenv.sh
+ |-- <i><config2-dir></i>
+ | |-- Make.defs
+ | |-- defconfig
+ | `-- setenv.sh
+ `-- <i>(other board-specific configuration sub-directories)</i>/
</pre></ul>
<h3><a name="summaryofconfigfiles">2.3.2 Summary of Files</a></h3>
@@ -502,10 +513,15 @@
It must support the following targets: <code>libext$(LIBEXT)</code>, <code>clean</code>, and <code>distclean</code>.
</li>
</ul>
-<h4><a name="boardconfigfiles">2.3.2.2 Board Specific Configuration Files</a></h4>
+<h4><a name="boardconfigsubdirs">2.3.2.2 Board Specific Configuration Sub-Directories</a></h4>
<p>
The <code>configs/</code><i><board-name></i><code>/</code> sub-directory holds all of the
files that are necessary to configure Nuttx for the particular board.
+ A board may have various different configurations using the common source files.
+ Each board configuration is described by three files: <code>Make.defs</code>, <code>defconfig</code>, and <code>setenv.sh</code>.
+ Typically, each set of configuration files is retained in a separate configuration sub-directory
+ (<i><config1-dir></i>, <i><config2-dir></i>, .. in the above diagram).
+
The procedure for configuring NuttX is described <a href="#configuringnuttx">below</a>,
This paragraph will describe the contents of these configuration files.
</p>
@@ -530,7 +546,7 @@
</li>
<li>
<code>defconfig</code>: This is a configuration file similar to the Linux
- configuration file. In contains varialble/value pairs like:
+ configuration file. In contains variable/value pairs like:
<ul>
<li><code>CONFIG_VARIABLE</code>=value</li>
</ul>
@@ -697,19 +713,20 @@
<p>
<b>Manual Configuration</b>.
Configuring NuttX requires only copying the
- <a href="#boardconfigfiles">board-specific configuration files</a> into the top level directory which appears in the make files as the make variable, <code>${TOPDIR}</code>.
+ <a href="#boardconfigsubdirs">board-specific configuration files</a> into the top level directory which appears in the make files as the make variable, <code>${TOPDIR}</code>.
This could be done manually as follows:
</p>
<ul>
- <li>Copy <code>configs/</code><i><board-name></i></code>/Make.def</code> to <code>${TOPDIR}/Make.defs</code>,<li>
- <li>Copy <code>configs/</code><i><board-name></i></code>/setenv.sh</code> to <code>${TOPDIR}/setenv.sh</code>, and</li>
- <li>Copy <code>configs/</code><i><board-name></i></code>/defconfig</code> to <code>${TOPDIR}/.config</code></li>
+ <li>Copy <code>configs/</code><i><board-name></i><code>/[</code><i><config-dir></i><code>/]Make.def</code> to <code>${TOPDIR}/Make.defs</code>,<li>
+ <li>Copy <code>configs/</code><i><board-name></i><code>/[</code><i><config-dir></i><code>/]setenv.sh</code> to <code>${TOPDIR}/setenv.sh</code>, and</li>
+ <li>Copy <code>configs/</code><i><board-name></i><code>/[</code><i><config-dir></i><code>/]defconfig</code> to <code>${TOPDIR}/.config</code></li>
</ul>
<p>
Where <i><board-name></i> is the name of one of the sub-directories of the
NuttX <a href="#DirStructConfigs"><code>configs/</code></a> directory.
This sub-directory name corresponds to one of the supported boards
identified <a href="#supportedboards">above</a>.
+ And <config-dir> is the optional, specific configuration directory for the board.
</p>
<p>
<b>Automated Configuration</b>.
@@ -718,7 +735,7 @@
</p>
<ul><pre>
cd tools
- ./configure.sh <i><board-name></i>
+ ./configure.sh <i><board-name></i></i><code>[/</code><i><config-dir></i><code>]</code>
</pre></ul>
<p>
@@ -747,14 +764,14 @@ make
That directory also holds:
</p>
<ul>
- <li>The makefile fragment <a href="#boardconfigfiles"><code>.config</code></a> that describes the current configuration.</li>
- <li>The makefile fragment <a href="#boardconfigfiles"><code>Make.defs</code></a> that provides customized build targers, and</li>
- <li>The shell script <a href="#boardconfigfiles"><code>setenv.sh</code></a> that sets up the configuration environment for the build.</li>
+ <li>The makefile fragment <a href="#boardconfigsubdirs"><code>.config</code></a> that describes the current configuration.</li>
+ <li>The makefile fragment <a href="#boardconfigsubdirs"><code>Make.defs</code></a> that provides customized build targers, and</li>
+ <li>The shell script <a href="#boardconfigsubdirs"><code>setenv.sh</code></a> that sets up the configuration environment for the build.</li>
</ul>
<p>
-The <a href="#boardconfigfiles"><code>setenv.sh</code></a> contains Linux environmental settings that are needed for the build.
-The specific environmental definitions are unique for each board but should include, as a minimum, updates to the <code>PATH</code> variable to include the full path to the architecture-specific toolchain identified in <a href="#boardconfigfiles"><code>Make.defs</code></a>.
-The <a href="#boardconfigfiles"><code>setenv.sh</code></a> only needs to be source'ed at the beginning of a session.
+The <a href="#boardconfigsubdirs"><code>setenv.sh</code></a> contains Linux/Cygwin environmental settings that are needed for the build.
+The specific environmental definitions are unique for each board but should include, as a minimum, updates to the <code>PATH</code> variable to include the full path to the architecture-specific toolchain identified in <a href="#boardconfigsubdirs"><code>Make.defs</code></a>.
+The <a href="#boardconfigsubdirs"><code>setenv.sh</code></a> only needs to be source'ed at the beginning of a session.
The system can be re-made subsequently by just typing <code>make</code>.
</p>
<p>
@@ -1548,6 +1565,22 @@ The system can be re-made subsequently by just typing <code>make</code>.
</li>
</ul>
+<h1><a name="apndxtrademarks">Appendix B: Trademarks</a></h1>
+
+ <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>
+
+<p>
+ NOTE: NuttX is <i>not</i> licensed to use the POSIX trademark. NuttX uses the POSIX
+ standard as a development guideline only.
+</p>
+
</body>
</html>
diff --git a/TODO b/TODO
index 2351579fa52186179d4bb4aec1e4888c21f9c229..f851000402be8f477de769a056cc89ac99b4fa09 100644
--- a/TODO
+++ b/TODO
@@ -234,9 +234,10 @@ o Pascal Add-On (pcode/)
Description: Need APIs to verify execution of P-Code from memory buffer.
Status: Open
- Priority: Medium
+ Priority: Low
- Description: Pascal add-on does not build with the SDCC compiler.
+ Description: Loader and object format may be too large for some small
+ memory systems. Consider ways to reduce memory footprint.
Status: Open
Priority: Medium
diff --git a/arch/README.txt b/arch/README.txt
index 52ad1f3e1b3eb680a6b17a547750aea63c04937a..0e5581cc40eaeeb9cfda9dd9405d6ab16663c318 100644
--- a/arch/README.txt
+++ b/arch/README.txt
@@ -125,7 +125,7 @@ Supported Architectures
arch/sim
A user-mode port of NuttX to the x86 Linux platform is available.
- The purpose of this port is primarily to support OS feature developement.
+ The purpose of this port is primarily to support OS feature development.
This port does not support interrupts or a real timer (and hence no
round robin scheduler) Otherwise, it is complete.
@@ -160,11 +160,12 @@ arch/pjrc-8051
8051 Microcontroller. This port is not quite ready for prime time.
arch/z16
- ZiLog z16f Microcontroller.
- STATUS: A work in progress
-
+ ZiLOG z16f Microcontroller.
+ STATUS: Released in nuttx-0.3.7. Fully functional other than issues
+ addressed in ${TOPDIR}/TODO.
+
arch/z80
- ZiLog z80 Microcontroller.
+ ZiLOG z80 Microcontroller.
STATUS: Functional with no known defects. There are still several
OS features that have not yet been tested (e.g., networking).
diff --git a/configs/README.txt b/configs/README.txt
index fb6c655657d6d7796693942d6121cd0626f4088b..e7675a947f40a917ec8f0d13fdd9a3e665eb64a8 100644
--- a/configs/README.txt
+++ b/configs/README.txt
@@ -33,7 +33,8 @@ o Board specific files. In order to be usable, the chip must be
These board-specific configuration files can be found in the
configs/<board-name>/ sub-directories and are discussed in this
- README.
+ README. Additional configuration information maybe available in
+ board-specific configs/<board-name>/README.txt files.
The configs/ subdirectory contains configuration data for each board. These
board-specific configurations plus the architecture-specific configurations in
@@ -53,10 +54,15 @@ following characteristics:
|-- src/
| |-- Makefile
| `-- (board-specific source files)
- |-- Make.defs
- |-- defconfig
- `-- setenv.sh
-
+ |-- <config1-dir>
+ | |-- Make.defs
+ | |-- defconfig
+ | `-- setenv.sh
+ |-- <config2-dir>
+ | |-- Make.defs
+ | |-- defconfig
+ | `-- setenv.sh
+ ...
Summary of Files
^^^^^^^^^^^^^^^^
@@ -74,6 +80,12 @@ src/Makefile -- This makefile will be invoked to build the board specific
drivers. It must support the following targets: libext$(LIBEXT), clean,
and distclean.
+A board may have various different configurations using these common source
+files. Each board configuration is described by three files: Make.defs,
+defconfig, and setenv.sh. Typically, each set of configuration files is
+retained in a separate configuration sub-directory (<config1-dir>,
+<config2-dir>, .. in the above diagram).
+
Make.defs -- This makefile fragment provides architecture and
tool-specific build options. It will be included by all other
makefiles in the build (once it is installed). This make fragment
@@ -90,7 +102,7 @@ Make.defs -- This makefile fragment provides architecture and
different if CONFIG_DEBUG=y.
defconfig -- This is a configuration file similar to the Linux
- configuration file. In contains varialble/value pairs like:
+ configuration file. In contains variable/value pairs like:
CONFIG_VARIABLE=value
@@ -137,7 +149,7 @@ defconfig -- This is a configuration file similar to the Linux
CONFIG_DEBUG_SCHED - enable OS debug output (disabled by
default)
CONFIG_DEBUG_MM - enable memory management debug output
- (disabld by default)
+ (disabled by default)
CONFIG_DEBUG_NET - enable network debug output (disabled
by default)
CONFIG_DEBUG_FS - enable filesystem debug output (disabled
@@ -160,7 +172,7 @@ defconfig -- This is a configuration file similar to the Linux
be disabled by setting this value to zero.
CONFIG_SCHED_INSTRUMENTATION - enables instrumentation in
scheduler to monitor system performance
- CONFIG_TASK_NAME_SIZE - Spcifies that maximum size of a
+ CONFIG_TASK_NAME_SIZE - Specifies that maximum size of a
task name to save in the TCB. Useful if scheduler
instrumentation is selected. Set to zero to disable.
CONFIG_START_YEAR, CONFIG_START_MONTH, CONFIG_START_DAY -
@@ -194,7 +206,7 @@ defconfig -- This is a configuration file similar to the Linux
Allow for architecture optimized implementations
The architecture can provide optimized versions of the
- following to improve sysem performance
+ following to improve system performance
CONFIG_ARCH_MEMCPY, CONFIG_ARCH_MEMCMP, CONFIG_ARCH_MEMMOVE
CONFIG_ARCH_MEMSET, CONFIG_ARCH_STRCMP, CONFIG_ARCH_STRCPY
@@ -282,12 +294,12 @@ Supported Boards
configs/sim
A user-mode port of NuttX to the x86 Linux platform is available.
- The purpose of this port is primarily to support OS feature developement.
+ The purpose of this port is primarily to support OS feature development.
This port does not support interrupts or a real timer (and hence no
round robin scheduler) Otherwise, it is complete.
NOTE: This target will not run on Cygwin probably for many reasons but
- first off because it uses some of the same symbols as does cygwind.dll.
+ first off because it uses some of the same symbols as does cygwin.dll.
configs/c5471evm
This is a port to the Spectrum Digital C5471 evaluation board. The
@@ -324,7 +336,7 @@ configs/pjrc-8051
configs/z16f2800100zcog
z16f Microncontroller. This port use the Zilog z16f2800100zcog
development kit and the Zilog ZDS-II Windows command line tools. The
- development envirnoment is Cygwin under WinXP.
+ development environment is Cygwin under WinXP.
configs/z80zim
z80 Microcontroller. This port uses a Z80 instruction set simulator.
@@ -341,14 +353,15 @@ Configuring NuttX
Configuring NuttX requires only copying
- configs/<board-name>/Make.def to ${TOPDIR}/Make.defs
- configs/<board-name>/setenv.sh to ${TOPDIR}/setenv.sh
- configs/<board-name>/defconfig to ${TOPDIR}/.config
+ configs/<board-name>/<config-dir>/Make.def to ${TOPDIR}/Make.defs
+ configs/<board-name>/<config-dir>/setenv.sh to ${TOPDIR}/setenv.sh
+ configs/<board-name>/<config-dir>/defconfig to ${TOPDIR}/.config
-There is a script that automates these steps. The following steps will
-accomplish the same configuration:
+tools/configure.sh
+ There is a script that automates these steps. The following steps will
+ accomplish the same configuration:
cd tools
- ./configure.sh <board-name>
+ ./configure.sh <board-name>/<config-dir>
diff --git a/configs/z16f2800100zcog/README.txt b/configs/z16f2800100zcog/README.txt
index 0a63025fe469e75b22d41d1644544eb6803d12ad..9c7fc762acffd140afd19a4ad7627eeac179483a 100644
--- a/configs/z16f2800100zcog/README.txt
+++ b/configs/z16f2800100zcog/README.txt
@@ -4,15 +4,27 @@ README.txt
ZDS-II Compiler Versions
^^^^^^^^^^^^^^^^^^^^^^^^
-The ZDS-II version 4.10.2 will not compiler NuttX. It reports "internal
-errors" on some of the files. Upgreads to ZDS-II are available for download
-from the Zilog website: http://www.zilog.com/software/zds2.asp
+4.10.2
+ The ZDS-II version 4.10.2 will not compile NuttX. It reports "internal
+ errors" on some of the files. Upgrades to ZDS-II are available for
+ download from the Zilog website: http://www.zilog.com/software/zds2.asp
-Thusfar, I have encountered no insolvable problems with the newer 4.11.0
-version of the toolchain.
+4.11.0
+ NuttX compiles correctly with the newer 4.11.0 version of the ZDS-II
+ toolchain. However, I have found a few issues:
+
+ - The code will not run without the -reduceopt option. There is,
+ apparently, some optimization related issue. This issue has not
+ been analyzed as of this writing.
+
+ - Not all NuttX logic will not run with the -regvars option. There is
+ at least one failure that has been reported to ZiLOG as incident 81400.
+
+ - The Pascal add-on interpreter includes a large switch statement and
+ exposes another compiler problem. This is reported as incident 81459.
If you use any version of ZDS-II other than 4.11.0 or if you install ZDS-II
-at anly location other than the default location, you will have to modify
+at any location other than the default location, you will have to modify
two files: (1) configs/z16f2800100zcog/*/setenv.sh and (2)
configs/z16f2800100zcog/*/Make.defs.
@@ -45,4 +57,4 @@ available:
Configures to use examples/pashello for execution from FLASH
See examples/README.txt for information about pashello.
-Check out any README.txt files in these <sub-directory>s.
+Check out any README.txt files in these <sub-directory>s.
diff --git a/configs/z80sim/README.txt b/configs/z80sim/README.txt
index 5026b23d8b62ea73e78b8e38a4329207b98126d0..77972c2d4ecac09eb3045d3f37cedbb5ebece51b 100644
--- a/configs/z80sim/README.txt
+++ b/configs/z80sim/README.txt
@@ -6,7 +6,7 @@ The instruction set emulator can be found in the NuttX CVS at
http://nuttx.cvs.sourceforge.net/nuttx/misc/sims/z80sim
The SDCC toolchain is available from http://sdcc.sourceforge.net/. All
-testing has been performed using verison 2.6.0 of the SDDC toolchain.
+testing has been performed using version 2.6.0 of the SDCC toolchain.
Configuring NuttX
^^^^^^^^^^^^^^^^^
diff --git a/examples/README.txt b/examples/README.txt
index e71d3f82354bca92477ff9280116c3d0efb8911d..39dee7f8fff5b278fec91351cadfa7ae0a59e966 100644
--- a/examples/README.txt
+++ b/examples/README.txt
@@ -26,7 +26,7 @@ examples/ostest
examples/nsh
^^^^^^^^^^^^
- This directory containst the NuttShell (NSH). This is a simple
+ This directory contains the NuttShell (NSH). This is a simple
shell-like application. With some additional development, NSH will
someday be a great NuttX application debugger. At present, NSH
supports the following commands: