LinuxCNC 2.5.1 RTAI Version

Hi guys!

I have a question about the rtai version installed on LinuxCNC 2.5.1! I think it's 3.8 but when i try to recompile it (because i need to change the configuration file to use the module for remote procedure call over net) i've compilation errors generated by a bad configuration of the pathced kernel!

Insted, if i compile the 3.9 version it's alla fine... but i need to run programs that use the 3.8 version (i don't know if it's a problem!!)


Any suggestions???

Thanks a lot!

I have a question about the rtai version installed on LinuxCNC 2.5.1

Your terminology is confused, I assume that you need to recompile the RTAI kernel, not the realtime system, but since you don't say what module and which config file it is hard to tell.

The procedure is briefly
Compile kernel with suitable rtai patch from either magma or rtai
Boot that kernel and then compile realtime against it
Then recompile Linuxcnc against the new kernel / realtime

This link is out of date in a couple of areas but describes the process in detail
code.google.com/p/neo-technical/wiki/emc2ubuntu

I think the changes needed are tcl8.5-dev and tk8.5-dev instead of 8.4 and python-old-doc-tools instead of python2.5

I have always used the magma files not rtai and not had any problem with the realtime system
I think the two are pretty well the same.
The link gives the repository address.

regards

Hi ArcEye and thank for your respond!

I'm really confesd... i think that linuxCNC run a patched rtai kernl yet. Infact i've no problem in compile the last version of rtai (3.9). In addition, rtai 3.8 is installed on the system by default. I need to change rtai configuration (so reconfigure rtai installation, and recompile rtai). I've choose linuxCnc for this reason, avoid to recompile linux kernet to patch it with rtai patch!

Mybe i can be more clear...

I need to install this package on my machine ( www.rtai.org/ ). This package required an HAL patch installed on the kernel. To avoid to recompule linux kernel with a patch i've chose to install linuxCnc. When i install linuxCnc i've rtai 3.8 modeules, so i can add this module to the kernel to run realtime programs (write by me).

Unfortunately i need a module called rtai_netrpc.ko that appera just modifing the configuration file befor install the package ( www.rtai.org/ ). So i've tried to reconfigure the packege before to reinstall but in the "make menuconfig" fase, he give me some errors that i've traced to a bad kernel configuration. So my question. How version of rtai is installed on linuxcnc?? Anyone had try to reinstalla rtai 3.8 on linuxcnc??

Thanks... and sorry for the confusion!

Hi

The module you want is part of the standard magma CVS, I have it installed on my machine

See the previous link I gave you
Fetch with cvs -d:pserver:anonymous@cvs.gna.org:/cvs/rtai co magma

I don't know which version of rtai / magma was used with the 2.6.32-132 kernel, but it will have been one that was stable about 2-3 years ago, so might possibly be 3.8 but more likely 3.7.
(guesstimate from the date stamps on the 2.6.32 patch and the rtai version dates)

Since you only have the binaries of the realtime system built against this kernel and not the source, and you want to use rtai 3.8, the easiest thing to do, will probably be to build a new kernel, then build magma against it and then Linuxcnc.
You can use any kernel that there are patches for, I have built 2.6.37 and 2.6.38 and both work, plus they have support for some newer hardware.

regards

i've compilation errors generated by a bad configuration of the pathced kernel!

OK I have now built rtai 3.8 on the stock 2.6.32-132 rtai kernel, just to show it can be done.

This is what I did

Downloaded kernel 2.6.32 from www.kernel.org and placed in /usr/src with a symlink to it named /usr/src/linux
Patched the kernel with the ...../rtai/base/arch/x86/patches/hal-linux-2.6.32.2-x86-2.5-00.patch
Imported the rtai kernel .config from the link I gave you
Run make menuconfig and set the processor type and saved
Ran make to ensure it ran OK then aborted it

Downloaded rtai-3.8 and placed in /usr/src
Ran make menuconfig and set the processor numbers and enabled C99 maths
configure then runs and completes OK
Ran make and voila, all modules including rtai_netrpc.ko are built

When I tried to build it with just the kernel headers in place, the build errored out at almost the first include
It needs the kernel sources and the .config to build, even though you don't need to build a new kernel

Whether you will be able to insert the new module and get depmod to have it loadable is another matter.
I still think that long term it would be easier to just build the new kernel, install the modules, boot the new kernel and then build rtai against that running kernel and ensure that the module will be the correct format and will load.

Hope this helps a bit

regards

PS

Just found that the rtai version used with 2.6.32-rtai was 3.8.1

There is a config script for it in /usr/realtime-2.6.32-132-rtai/share/rtai