@c @c @c COPYRIGHT (c) 1988-1999. @c On-Line Applications Research Corporation (OAR). @c All rights reserved. @c @c $Id$ @c @chapter Building RTEMS @section Unpack the RTEMS Source Use the following command sequence to unpack the RTEMS source into the tools directory: @example cd tools tar xzf ../archive/@value{RTEMS-TAR} @end example @section Add /bin to Executable PATH In order to compile RTEMS, you must have the cross compilation toolset in your search patch. The following command appends the directory where the tools were installed in the previous chapter: @example export PATH=$PATH:/bin @end example @b{NOTE:} The above command is in Bourne shell (@code{sh}) syntax and should work with the Korn (@code{ksh}) and GNU Bourne Again Shell (@code{bash}). It will not work with the C Shell (@code{csh})or derivatives of the C Shell. @section Verifying the Operation of the Cross Toolset In order to insure that the cross-compiler is invoking the correct subprograms (like @code{as} and @code{ld}), one can test assemble a small program. When in verbose more, @code{gcc} prints out information showing where it found the subprograms it invokes. Place the following function in a file named @code{f.c}: @example int f( int x ) @{ return x + 1; @} @end example Then assemble the file using a command similar to the following: @example m68k-rtems-gcc -v -S f.c @end example Where @code{m68k-rtems-gcc} should be changed to match the installed name of your cross compiler. The result of this command will be a sequence of output showing where the cross-compiler searched for and found its subcomponents. Verify that these paths correspond to your . @b{NOTE:} One of the most common installation errors is for the cross-compiler not to be able to find the cross assembler and default to using the native @code{as}. This can result in very confusing error messages. @section Generate RTEMS for a Specific Target and BSP @subsection Using the bit_rtems script The simplest way to build RTEMS is to use the @code{bit_rtems} script. This script interprets the settings in the @code{user.cfg} file to enable or disable the various RTEMS options. This script is invoked as follows: @example ./bit_rtems CPU [BSP] @end example Where CPU is one of the RTEMS supported CPU families from the following list: @itemize @bullet @item hppa1.1 @item i386 @item i386-elf @item i386-go32 @item i960 @item m68k @item mips64orion @item powerpc @item sh @item sparc @end itemize BSP is a supported BSP for the selected CPU family. The list of supported BSPs may be found in the file tools/@value{RTEMS-UNTAR}/README.configure in the RTEMS source tree. If the BSP parameter is not specified, then all supported BSPs for the selected CPU family will be built. @b{NOTE:} The POSIX API must be enabled to use GNAT/RTEMS. @subsection Using the RTEMS configure Script Directly Make a build directory under tools and build the RTEMS product in this directory. The ../@value{RTEMS-UNTAR}/configure command has numerous command line arguments. These arguments are discussed in detail in documentation that comes with the RTEMS distribution. In the installation described in the section "Unpack the RTEMS source", these configuration options can be found in the file tools/@value{RTEMS-UNTAR}/README.configure. The GNAT/RTEMS run-time implementation is based on the POSIX API. Thus the RTEMS configuration for a GNAT/RTEMS environment MUST include the @code{--enable-posix} flag. The following shows the command sequence required to configure, compile, and install RTEMS with the POSIX API enabled. RTEMS will be built to target the @code{BOARD_SUPPORT_PACKAGE} board. @example mkdir build-rtems cd build-rtems ../@value{RTEMS-UNTAR}/configure --target= \ --enable-posix \ --enable-rtemsbsp=\ --prefix= gmake all install @end example Where the list of currently supported of 's and 's can be found in tools/@value{RTEMS-UNTAR}/README.configure. is the installation point from the previous step "Modify the bit_ada Script" in the build of the tools.