2.8. Build Your Application¶
You tested a BSP in the previous section. We built the erc32 BSP
and it is installed under $HOME/quick-start/rtems/5.
We will now create a simple Hello World application with a Git repository and using the Waf build system.
The application is be created in $HOME/quick-start/app/hello.
In the output in this section the base directory $HOME/quick-start was
replaced by $BASE.
The steps in this section assume you are in the directory
$HOME/quick-start/app/hello after the first step changes to
it.
Setup the application work space. Create a new Git repository, download the Waf build system, and the RTEMS Waf.
Create the application directory and change into it:
mkdir -p $HOME/quick-start/app/hello
cd $HOME/quick-start/app/hello
Download the Waf build system and set it to executable:
curl https://waf.io/waf-2.0.19 > waf
chmod +x waf
Initialise a new Git repository:
git init
Add RTEMS Waf support as a Git sub-module and initialise it:
git submodule add git://git.rtems.org/rtems_waf.git rtems_waf
Create the application source files. Three files are created with an editor of your choice.
First create a C file that configures RTEMS. Using an editor create a
file called init.c and copy the following configuration
settings:
/*
* Simple RTEMS configuration
*/
#define CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER
#define CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER
#define CONFIGURE_UNLIMITED_OBJECTS
#define CONFIGURE_UNIFIED_WORK_AREAS
#define CONFIGURE_RTEMS_INIT_TASKS_TABLE
#define CONFIGURE_INIT
#include <rtems/confdefs.h>
Create the Hello World application source file. Using an editor
create hello.c and copy the follow code:
/*
* Hello world example
*/
#include <rtems.h>
#include <stdlib.h>
#include <stdio.h>
rtems_task Init(
rtems_task_argument ignored
)
{
printf( "\nHello World\n" );
exit( 0 );
}
Finally create the Waf script. Using an editor create wscript
and copy the Waf script:
#
# Hello world Waf script
#
from __future__ import print_function
rtems_version = "5"
try:
import rtems_waf.rtems as rtems
except:
print('error: no rtems_waf git submodule')
import sys
sys.exit(1)
def init(ctx):
rtems.init(ctx, version = rtems_version, long_commands = True)
def bsp_configure(conf, arch_bsp):
# Add BSP specific configuration checks
pass
def options(opt):
rtems.options(opt)
def configure(conf):
rtems.configure(conf, bsp_configure = bsp_configure)
def build(bld):
rtems.build(bld)
bld(features = 'c cprogram',
target = 'hello.exe',
cflags = '-g -O2',
source = ['hello.c',
'init.c'])
Configure the application using Waf’s configure command:
./waf configure --rtems=$HOME/quick-start/rtems/5 --rtems-bsp=sparc/erc32
The output will be something close to:
Setting top to : $BASE/app/hello
Setting out to : $BASE/app/hello/build
RTEMS Version : 5
Architectures : sparc-rtems5
Board Support Package (BSP) : sparc-rtems5-erc32
Show commands : no
Long commands : no
Checking for program 'sparc-rtems5-gcc' : $BASE/rtems/5/bin/sparc-rtems5-gcc
Checking for program 'sparc-rtems5-g++' : $BASE/rtems/5/bin/sparc-rtems5-g++
Checking for program 'sparc-rtems5-gcc' : $BASE/rtems/5/bin/sparc-rtems5-gcc
Checking for program 'sparc-rtems5-ld' : $BASE/rtems/5/bin/sparc-rtems5-ld
Checking for program 'sparc-rtems5-ar' : $BASE/rtems/5/bin/sparc-rtems5-ar
Checking for program 'sparc-rtems5-nm' : $BASE/rtems/5/bin/sparc-rtems5-nm
Checking for program 'sparc-rtems5-objdump' : $BASE/rtems/5/bin/sparc-rtems5-objdump
Checking for program 'sparc-rtems5-objcopy' : $BASE/rtems/5/bin/sparc-rtems5-objcopy
Checking for program 'sparc-rtems5-readelf' : $BASE/rtems/5/bin/sparc-rtems5-readelf
Checking for program 'sparc-rtems5-strip' : $BASE/rtems/5/bin/sparc-rtems5-strip
Checking for program 'sparc-rtems5-ranlib' : $BASE/rtems/5/bin/sparc-rtems5-ranlib
Checking for program 'rtems-ld' : $BASE/rtems/5/bin/rtems-ld
Checking for program 'rtems-tld' : $BASE/rtems/5/bin/rtems-tld
Checking for program 'rtems-syms' : $BASE/rtems/5/bin/rtems-syms
Checking for program 'rtems-bin2c' : $BASE/rtems/5/bin/rtems-bin2c
Checking for program 'tar' : /usr/bin/tar
Checking for program 'gcc, cc' : $BASE/rtems/5/bin/sparc-rtems5-gcc
Checking for program 'ar' : $BASE/rtems/5/bin/sparc-rtems5-ar
Checking for program 'g++, c++' : $BASE/rtems/5/bin/sparc-rtems5-g++
Checking for program 'ar' : $BASE/rtems/5/bin/sparc-rtems5-ar
Checking for program 'gas, gcc' : $BASE/rtems/5/bin/sparc-rtems5-gcc
Checking for program 'ar' : $BASE/rtems/5/bin/sparc-rtems5-ar
Checking for c flags '-MMD' : yes
Checking for cxx flags '-MMD' : yes
Compiler version (sparc-rtems5-gcc) : 7.5.0 20191114 (RTEMS 5, RSB 5.1.0, Newlib fbaa096)
Checking for a valid RTEMS BSP installation : yes
Checking for RTEMS_DEBUG : no
Checking for RTEMS_MULTIPROCESSING : no
Checking for RTEMS_NEWLIB : yes
Checking for RTEMS_POSIX_API : yes
Checking for RTEMS_SMP : no
Checking for RTEMS_NETWORKING : no
'configure' finished successfully (0.686s)
Build the application:
./waf
The output will be something close to:
Waf: Entering directory `$BASE/app/hello/build/sparc-rtems5-erc32'
[1/3] Compiling init.c
[2/3] Compiling hello.c
[3/3] Linking build/sparc-rtems5-erc32/hello.exe
Waf: Leaving directory `$BASE/app/hello/build/sparc-rtems5-erc32'
'build-sparc-rtems5-erc32' finished successfully (0.183s)
Run the executable:
$HOME/quick-start/rtems/5/bin/rtems-run --rtems-bsps=erc32-sis build/sparc-rtems5-erc32/hello.exe
The output will be something close to:
RTEMS Testing - Run, 5.1.0
Command Line: $BASE/rtems/5/bin/rtems-run --rtems-bsps=erc32-sis build/sparc-rtems5-erc32/hello.exe
Host: FreeBSD hihi 12.1-RELEASE-p2 FreeBSD 12.1-RELEASE-p2 GENERIC amd64
Python: 3.7.6 (default, Jan 30 2020, 01:18:54) [Clang 6.0.1 (tags/RELEASE_601/final 335540)]
Host: FreeBSD-12.1-RELEASE-p2-amd64-64bit-ELF (FreeBSD hihi 12.1-RELEASE-p2 FreeBSD 12.1-RELEASE-p2 GENERIC amd64 amd64)
SIS - SPARC/RISCV instruction simulator 2.21, copyright Jiri Gaisler 2019
Bug-reports to jiri@gaisler.se
ERC32 emulation enabled
Loaded build/sparc-rtems5-erc32/hello.exe, entry 0x02000000
Hello World
*** FATAL ***
fatal source: 5 (RTEMS_FATAL_SOURCE_EXIT)
fatal code: 0 (0x00000000)
RTEMS version: 5.1.0
RTEMS tools: 7.5.0 20191114 (RTEMS 5, RSB 5.1.0, Newlib fbaa096)
executing thread ID: 0x08a010001
executing thread name: UI1
cpu 0 in error mode (tt = 0x101)
107883 0200b6c0: 91d02000 ta 0x0
Run time : 0:00:01.011474
Commit the application to the repository:
git add init.c hello.c wscript
git commit -m "My first RTEMS application."