RTEMS for VxWorks users - Series of dumb questions

Victor V. Vengerov Victor.Vengerov at oktetlabs.ru
Thu Jul 1 10:02:22 UTC 2004


I'll try to answer this - please correct me if I'm wrong somewhere.

1001 wrote:

> I downloaded rtems-4.6.1.tar.bz2 and untarred it.
> Let us call it 'don't touch area'.
> I then created a new dir (let us call it 'work area')
> and from there called configure which was in 'don't
> touch area'. In the 'work area' I called make. After
> few hours the make was done.
> Q1 What is analogous to a vxWorks BSP in RTEMS and
> where is big tree is it? In 'don't touch area' or in
> 'work area'?
Currently it is in "don't touch area", although, AFAIK, some efforts 
were made
to allow independent BSP packaging. See c/src/lib/libbsp/<cpu-arch>/<board>

> Q2 What is analagous to 'vxWorks' kernel image in
> RTEMS? And where in 'work area' will I find it?
Results of RTEMS build are libraries which should be linked against RTEMS
application. After 'make install' these libraries, as well as RTEMS 
headers and
Makefile fragments, installed to the directory relative to your "prefix"
path, <prefix>/<target>/<bsp>.

Prefix is a place where all your stuff installed; normally it points to

There is no "kernel image" in the literally same sense as in VxWorks. 
You may
build your RTEMS application and link it against RTEMS libraries. Normally,
application independent of RTEMS installation. See hello_world_c example
in examples-4.6.1.tar.gz

As part of RTEMS build, several simple sample RTEMS apps are normally
built, although they are not installed to <prefix>. You may try to run 
Also, you may request to build RTEMS tests suite (--enable-tests option in
configure) and run separate RTEMS tests.

> Q3 What is analagous to 'boot.bin' flash rom boot
> image in RTEMS, if any? And where in 'work area' will
> I find it?
You mean bootrom.bin?

There are no standard boot image in RTEMS. You may use available boot
loader, although. I beleive, MVME2400 shipped with monitor program burned
in the flash which allows booting. Open source boot loaders exists for many
architectures, and they can be adopted for your board. Finally, you may
want to create boot loader as RTEMS application - it may be useful, for
example, when RTEMS has networking driver and available boot loader
can not boot using your networking hardware. But all of these out of
RTEMS scope.

> Q4 Does RTEMS have two images (flashable and
> downoadable kernel) format?
This is BSP issue mainly. Usually, BSP may provide variants of linker 
(linkcmds) which allows execution from RAM or flash. Startup code
should support this as well (by determining is it necessary to copy 
data and/or code to RAM,). No out-of-box solution for code compression
exists, sorry.

> Q5 How do I load a kernel into memory if there is no
> analogous to 'boot.bin'
As I mention before, you should use boot loader/monitor available for your
board. It may be provided by board supplier.

You may adapt Makefile rule to produce loadable image in the format
compatible with your boot loader. See files make/custom/*;
make macro make-exe.

Hope this helps.


Victor Vengerov
OKTET Labs, St.-Petersburg, Russia  http://www.oktetlabs.ru
Phone: +78124286709 (office) +78129389372 (mobile) +78124281653 (home)

More information about the users mailing list