LinuxCNC / Ethercat on recent ubuntu & kernel

Hi,

Hopefully this is vaguely the right place to post this, but I'm looking for a bit of assistance to setup a fairly up-to-date system with which to get into helping developing LinuxCNC. My specific interest is in controlling Ethercat slaves that I have developed based on an Infineon XMC series MCU (& have controlled using TwinCAT to date!).

My progress so far is:

1) Install recent-ish x64 Ubuntu distribution (20.04 caused me endless headaches with the removal of python 2 support, so for now I've stuck with 18.04)
2) Compile the latest stable kernel with PREEMPT_RT support. (at the moment 5.10.25-rt35 #1 SMP PREEMPT_RT)
3) Build linux-cnc from source, with support for PREEMPT_RT (i.e. --with-realtime=uspace)

All this was fairly straightforward, but I'm having difficulty understanding how to proceed with integrating Ethercat support.

My understanding is that linuxcnc leverages the IgH/Etherlab "EtherCAT Master for Linux"
And that a "HAL" component for linuxcnc "github.com/sittner/linuxcnc-ethercat.git" communicates with this.

Most build instructions I've seen use "ec-debianize", which from what I understand is an automated build process to configure & build the etherlab master in a way that is suitable to integrate with linuxcnc-ethercat. This is the part I am having major issues with, as apparently it is not suitable for use with newer linux kernels.

Now, I can checkout the IgH/Etherlab "EtherCAT Master for Linux" from their current repository gitlab.com/etherlab.org/ethercat.git & happily build this against current kernel headers - I just don't really know what I need to do to integrate it with linuxcnc-ethercat, as ec-debianize appears to apply lots of patches & do things I don't fully understand.

If anyone can give me a brief rundown on how everything EtherCat related in linuxcnc actually integrates under the hood, I'd love to get into a position I can contribute something back to this awesome project.

Thanks!
Paul

You can have a look at my notes from building ethercat support support on raspberry pi forum.linuxcnc.org/10-advanced-configura...at-on-raspberry-pi-4 . It doesn't use ec-debianize and might work better.

Thanks for getting back - I'd come across your post previously & I did think it was more in line with what I need to do.

One further question, how come you & most others I've seen use the code at github.com/icshwi/etherlabmaster?

I don't quite understand what functionality this gives over & above the latest code from IgH, or indeed what the point of the "patchset" it uses is!

I'll get chance to try it out a bit later, so hopefully it will all become clear then!

Cheers,
Paul

It is just because the honourable icshwi was active in the long thread about ethercat and from there this work was picked up.

I got lost with ec-debianize. It didn't build cleanly, and I had no clue on where to start look for amending the build. Icshwi's work came in handy, I don't know more about that really.

Great, that makes total sense.

I'm coming at all this fairly green and whilst I've a good background in C/C++ & embedded development, there's a lot to wrap my head around - so thanks for your patience!