[Home]VxWorks

Last edit: Peter Favrholdt on December 10, 2006 23:07 (2685 days, 5 hours and 0 minutes ago) (diff)
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From the mailinglist

as pointed out by Philippe, each of us proposed a different alternative
to the use of the RTAI VxWorks skin in kernel mode. These two
alternatives might lead to confusion. So, let us state it clearly. There
are three ways to use the RTAI VxWorks skin.

First way: User-space VM.
If you want the comfort of user space realtime and are willing to accept
the tradeoffs it implies, you can use the so called VxWorks virtual
machine. In the configuration menu (make config, menuconfig or xconfig)
activate the options:
  Core system / Xenomai sub-system / User-space VM support
  Add-ons / Xenomai skins / VxWorks emulator

After installation, you will find a few libraries in the directory
rtai-config --libdir`. In order to run your VxWorks code in userspace
realtime, you will have to link it (please Philippe correct me if I am
wrong) with:
  libvxworks.a
  libxenomai.a
  libfusion.a


Second way: Kernel space.
If you can not afford the comfort of user space, you have to compile and
use the VxWorks skin as a kernel module (but have a look at the third
way, it might help you). In the configuration menu, activate the option:
  Add-ons / Xenomai skins / VxWorks emulator

Repeating what Philippe wrote, you then have to compile your program as
a kernel module, using rtai-config --module-cflags, and insmod the
following modules:
   adeos.o (unless statically bound to the kernel)
   rtai_hal.o
   rtai_xeno.o
   rtai_vxworks.o
   your_app_module.o


Third way: The RTAI simulator.
If you plan to use kernel space, but would like to run your code in
a simulator before you give it a chance to cause kernel oopses, you
should definitely try this third way. In the configuration menu,
activate the options:
  Add-ons / Xenomai skins / VxWorks emulator
  RTAI Simulator / Minute Virtual Machine
  RTAI Simulator / GCC tarball (give a path)

You have to download a gcc (version 2.95.3) tarball from your nearest
GNU ftp mirror and provide the path to RTAI Simulator configuration
system. As part of the compilation process, gcc sources will be patched,
compiled and an instrumented compiler, gcic, will be installed.

In order to compile your code for the RTAI simulator, you need to
compile it with gcic and link it with the following libraries:
   libvxworks_s.a
   libxenomai_s.a
   libmvm.so or libmvm.a (or libmvm.la if you use libtool)
   libmvmutils.so, libmvmutils.a or libmvmutils.la
   libxenosa.a

You will then be able to run your code into the xenoscope, a graphical,
real-time OS aware debugger.
  
For the moment, there is no support for this into rtai-config, but you
may give a look at the "satch" example (it uses the psos skin, but this
does not make a great difference). You will find it in the directory
rtai-sim/examples/psos+/satch.



The same goes for the other skins, namely psos+, vrtx and uitron. pse51
is a little bit different, it has no user-space VM support.


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