Update README.txt
This commit is contained in:
Gregory Nutt
parent
2967dd1570
commit
f50686c621
87
README.txt
87
README.txt
@ -105,7 +105,7 @@ Semi-Optional apps/ Package
|
||||
It is call "Semi-optional" because if you don't have some apps/
|
||||
directory, NuttX will *fail* to build!
|
||||
|
||||
Download the unpack the apps tarball in the same directly where you
|
||||
Download then unpack the apps tarball in the same directory where you
|
||||
unpacked the NuttX tarball. After you unpack the apps tarball, you
|
||||
will have a new directory called apps-version (where the version
|
||||
should exactly match the version of the NuttX tarball). Again, you
|
||||
@ -183,13 +183,37 @@ Notes about Header Files
|
||||
|
||||
Other C-Library Header Files.
|
||||
|
||||
Some toolchains are built with header files extracted from a C-library
|
||||
distribution (such as newlib). These header files must *not* be used
|
||||
with NuttX because NuttX provides its own, built-in C-Library. For
|
||||
toolchains that do include built-in header files from a foreign C-
|
||||
Library, NuttX must be compiled without using the standard header files
|
||||
that are distributed with your toolchain. This prevents including
|
||||
conflicting, incompatible header files (such as stdio.h).
|
||||
When a GCC toolchain is built, it must be built against a C library.
|
||||
The compiler together with the contents of the C library completes the
|
||||
C language definition and provides the complete C development
|
||||
environment. NuttX provides its own, built-in C library. So the
|
||||
complete, consistent C language definition for use with NuttX comes from
|
||||
the combination of the compiler and the header files provided by the
|
||||
NuttX C library.
|
||||
|
||||
When a GCC toolchain is built, it incorporates the C library header
|
||||
files into the compiler internal directories and, in this way, the C
|
||||
library really becomes a part of the toolchain. If you use the NuttX
|
||||
buildroot toolchain as described below under under "NuttX Buildroot
|
||||
Toolchain", your GCC toolchain will build against the NuttX C library
|
||||
and will incorporate the NuttX C library header files as part of the
|
||||
toolchain.
|
||||
|
||||
If you use some other, third-party tool chain, this will not be the
|
||||
case, however. Those toolchains were probably built against some
|
||||
other, incompatible C library distribution (such as newlib). Those
|
||||
tools will have incorporated the incompatible C library header files
|
||||
as part of the toolchain. These incompatible header files must *not*
|
||||
be used with NuttX because the will conflict with definitions in the
|
||||
NuttX built-in C-Library. For such toolchains that include header
|
||||
files from a foreign C-Library, NuttX must be compiled without using
|
||||
the standard header files that are distributed with your toolchain.
|
||||
This prevents including conflicting, incompatible header files such
|
||||
as stdio.h.
|
||||
|
||||
The math.h and stdarg.h are probably the two most trouble some header
|
||||
files to deal with. These troublesome header files are discussed in
|
||||
more detail below.
|
||||
|
||||
Header Files Provided by Your Toolchain.
|
||||
|
||||
@ -268,10 +292,12 @@ Instantiating "Canned" Configurations
|
||||
|
||||
configs/<board-name>/<config-dir>
|
||||
|
||||
Where <board-name> is the name of your development board and <config-dir>.
|
||||
Configuring NuttX requires only copying three files from the <config-dir>
|
||||
to the directory where you installed NuttX (TOPDIR) (and sometimes one
|
||||
additional file to the directory the NuttX application package (APPSDIR)):
|
||||
Where <board-name> is the name of your development board and <config-dir>
|
||||
is the name of the sub-directory containing a specific configuration for
|
||||
that board. Configuring NuttX requires only copying three files from the
|
||||
<config-dir> to the directory where you installed NuttX (TOPDIR) (and
|
||||
sometimes one additional file to the directory the NuttX application
|
||||
package (APPSDIR)):
|
||||
|
||||
Copy configs/<board-name>/<config-dir>/Make.def to ${TOPDIR}/Make.defs
|
||||
|
||||
@ -315,19 +341,26 @@ Instantiating "Canned" Configurations
|
||||
Refreshing Configurations
|
||||
-------------------------
|
||||
|
||||
Configurations can get out of date. As new configurations are added or
|
||||
removed, the contents of a default configuration can become out of synch
|
||||
Configurations can get out of date. As new configuration settings are
|
||||
added or removed or as dependencies between configuration settings
|
||||
change, the contents of a default configuration can become out of synch
|
||||
with the build systems. Hence, it is a good practice to "refresh" each
|
||||
configuration before making. To refresh the configuration, use the NuttX
|
||||
Configuration Tool like this:
|
||||
configuration after configuring and before making. To refresh the
|
||||
configuration, use the NuttX Configuration Tool like this:
|
||||
|
||||
make oldconfig
|
||||
|
||||
If you configuration is out of date, you will be prompted to resolve the
|
||||
issues detected by the configuration tool, that is, to provide values for
|
||||
the new configuration options in the build system. Doing this can save
|
||||
you a lot of problems down the road due to a bad configuration. The NuttX
|
||||
configuration is discussed in the following paragraph.
|
||||
AFTER you have instantiated the NuttX configuration as described above.
|
||||
The configuration step copied the .config file into place in the top-level
|
||||
NuttX directory; 'make oldconfig' step will then operate on that .config
|
||||
file to bring it up-to-date.
|
||||
|
||||
If you configuration is out of date, you will be prompted by 'make oldconfig'
|
||||
to resolve the issues detected by the configuration tool, that is, to
|
||||
provide values for the new configuration options in the build system. Doing
|
||||
this can save you a lot of problems down the road due to obsolete settings in
|
||||
the default board configuration file. The NuttX configuration tool is
|
||||
discussed in more detail in the following paragraph.
|
||||
|
||||
Confused about what the correct value for a new configuration item should
|
||||
be? Enter ? in response to the 'make oldconfig' prompt and it will show
|
||||
@ -336,12 +369,9 @@ Refreshing Configurations
|
||||
NuttX Configuration Tool
|
||||
------------------------
|
||||
|
||||
An automated tool is under development to support re-configuration
|
||||
of NuttX. This tool, however, is not yet quite ready for general
|
||||
usage.
|
||||
|
||||
This automated tool is based on the kconfig-frontends application
|
||||
available at http://ymorin.is-a-geek.org/projects/kconfig-frontends
|
||||
An automated tool has been incorported to support re-configuration
|
||||
of NuttX. This automated tool is based on the kconfig-frontends
|
||||
application available at http://ymorin.is-a-geek.org/projects/kconfig-frontends
|
||||
(A snapshot of this tool is also available at ../misc/tools). This
|
||||
application provides a tool called 'kconfig-mconf' that is used by
|
||||
the NuttX top-level Makefile. The following make target is provided:
|
||||
@ -355,6 +385,9 @@ NuttX Configuration Tool
|
||||
damage your configuration (see
|
||||
http://www.nuttx.org/doku.php?id=wiki:howtos:convertconfig).
|
||||
|
||||
How do we tell a new configuration from an old one? See "Incompatibilities
|
||||
with Older Configurations" below.
|
||||
|
||||
The 'menuconfig' make target depends on two things:
|
||||
|
||||
1. The Kconfig configuration data files that appear in almost all
|
||||
|
||||
Loading…
Reference in New Issue
Block a user