EtherCAT + Machinekit

[Michael Haberler]

Sascha Ittner of modusoft.de is working on EtherCAT for Machinekit

he sent me a link to this video: http://www.youtube.com/watch?v=M1LxQBjttWg 

- Michael

[Eren Basturk]

That looks so good. I hope that ethercat support will come for machinekit image

22 Mayıs 2014 Perşembe 20:28:18 UTC+3 tarihinde Michael Haberler yazdı:

[andy pugh]

On 22 May 2014 20:04, Eren Basturk <bastu...@gmail.com> wrote:

> That looks so good. I hope that ethercat support will come for machinekit
> image

Isn't there a problem with EtherCAT and GPL?

--
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto

[euerka]

Now i am working on powerlink, openpowerlink is BSD license.
since now beaglebone Black only have one Ethernet Port, so currently i try to use one board as master, another one as slave. Anyone have any idea about how to extend board Ethernet Port? let us say i need two.

[Jeff Pollard]

Hi,

  A FAQ regarding EtherCAT can be found here:

http://www.ethercat.org/en/faq.html#787

  It looks like a license is required to make a master, but it is free.  See 3.3 in the link or the quote copied below:
==============

• 3.3 How about licences? 

  There is a licence for implementing an EtherCAT master which is free of charge - the agreement demands compatibility, ensures that the licence remains free of charge and provides legal certainty. For slave devices EtherCAT has adopted the CAN license model (CAN is an excellent example for a standardized open technology that is protected by patents): The small license fee is "embedded" in the EtherCAT Slave Controller (ESC) chip, so that device manufacturers, end users, system integrators, tool manufacturers etc. do not have to pay a license.

=============
Jeff

[andy pugh]

On 24 May 2014 22:09, Jeff Pollard <xylot...@gmail.com> wrote:

> It looks like a license is required to make a master, but it is free. See
> 3.3 in the link or the quote copied below:

Perhaps it would be possible to make it an optional install, with a
separate licence agreement? Like some audio applications do with the
proprietary codecs.

[John Morris]

On 05/24/2014 04:46 PM, andy pugh wrote:
> On 24 May 2014 22:09, Jeff Pollard <xylot...@gmail.com> wrote:
>
>> It looks like a license is required to make a master, but it is free. See
>> 3.3 in the link or the quote copied below:
>
> Perhaps it would be possible to make it an optional install, with a
> separate licence agreement? Like some audio applications do with the
> proprietary codecs.

I've discussed this at some length with Sascha Ittner of Modusoft (wrote
the LinuxCNC interface to the IgH EtherCAT Master), Beckhoff's CEO Gerd
Hoppe, and others. There's a thread on the LinuxCNC dev mailing list
that is probably informative.

The issue comes down to IgH claiming to be GPL, but Beckhoff insisting
that an EtherCat master implementation needs a license that (while
free-as-in-beer) requires anyone who modifies and redistributes the
master implementation to obtain a license from Beckhoff. That
requirement is incompatible with GPL, which states that no extra
requirements may be added outside those in the GPL itself. Beckhoff's
CEO indicated that the EtherCat master license is not negotiable.

Given this situation, my thinking after many discussions with esp.
Sascha leans toward keeping EtherCat out of any official distribution,
but that *most likely* a 3rd party distributor of modules would not get
in too much trouble.

John

[Jeff Pollard]

Hi Michael,

Do you know if there is a wiki page regarding getting the EtherCAT installed on MachineKit in a BBB?
I was thinking of getting an FB1111-0140 (Beckhoff EtherCAT slave device) and playing if I can get (and compile) the source.
I'm pretty sure I could build the master Ethernet hardware.

Thanks,

Jeff

[Michael Haberler]

Hi Jeff,

On Wednesday, May 28, 2014 6:28:56 PM UTC+2, Jeff Pollard wrote:

Hi Michael,

Do you know if there is a wiki page regarding getting the EtherCAT installed on MachineKit in a BBB?

sorry, no - you'd need to prod Sascha; I urged him to post but he didnt, so I did it ;)

you can find his email on the emc-dev list

I was thinking of getting an FB1111-0140 (Beckhoff EtherCAT slave device) and playing if I can get (and compile) the source.
I'm pretty sure I could build the master Ethernet hardware.

I'm fairly sure this will work technically. I think it should remain a separate repo because of licensing issues. But that should not be a large hurdle.

I have no idea how this kind of interfacing works in terms of network latency; my guess is he used memory mapped I/O bypassing the kernel. That works fast but isnt particularly portable if this is the case

the challenge I see is to get decent performance with stock linux ethernet drivers, something Michal Geskiewicz has been after with his hm2_eth work - it looks like this is possible for servo setups on PC platforms

- Michael

[euerka]

Dear all, 

Since i would like use BBB as ethercat or powerlink master(buy commercial motor driver as slave), i post a question on( http://beagleboard.org/Community/Forums ), unfortunately i got a reply it is impossible to use PRU to implement since the signals were missed.

So it means if anyone implement ethercat master actually is with RTOS layer(Xenomai), what i post before about BBB xenomai latency slow will be problem?

Any idea?

[Michael Haberler]

I understand the Beagleboard is not suitable for PRU code using an Ethernet port, but other hardware might be better suited.

RTnet for Xenomai probably is not an option as I dont think there is is an RTNet ethernet driver for the BB.

I suggest to read the thread on emc-developers '[Emc-developers] HEADS UP: RT-preempt and network I/O/system calls from RTthreads probably not viable' ,which explores some other options.

- Michael

 

[John Morris]

On 06/02/2014 10:28 AM, Michael Haberler wrote:
>
>
> On Monday, June 2, 2014 4:56:58 PM UTC+2, euerka wrote:
>
> Dear all,
>
> Since i would like use BBB as ethercat or powerlink master(buy
> commercial motor driver as slave), i post a question on(
> http://beagleboard.org/Community/Forums
> <http://beagleboard.org/Community/Forums> ), unfortunately i got a
> reply it is impossible to use PRU to implement since the signals
> were missed.
>
> So it means if anyone implement ethercat master actually is with
> RTOS layer(Xenomai), what i post before about BBB xenomai latency
> slow will be problem?
>
> Any idea?
>
>
> I understand the Beagleboard is not suitable for PRU code using an
> Ethernet port, but other hardware might be better suited.
>
> RTnet for Xenomai probably is not an option as I dont think there is is
> an RTNet ethernet driver for the BB.

The IgH EtherCAT Master software carries its own modified ethernet
drivers. I didn't know RTnet is a drop-in replacement for EtherCAT NIC
drivers.

Some time back, Sascha updated all of the EtherCAT NIC drivers to the
then-unsupported Linux 3.5.7 in order to work with our Xenomai packages.
In just two days, he reported that all but one were straight-forward
updates, and one more had changed so much he had to add EtherCAT support
from scratch.

Two days! Maybe one of us average folk could muddle through it in a
week or two?

John

[Eren Basturk]

John,

If it is possible could you share the link which we can use ethercat commnucation? I would like to buy an ethercat hardware for BBB.

Thanks a lot

22 Mayıs 2014 Perşembe 20:28:18 UTC+3 tarihinde Michael Haberler yazdı:

Sascha Ittner of modusoft.de is working on EtherCAT for Machinekit

[Eren Basturk]

I mean ... a link about ethercat device with to use machinekit image

2 Haziran 2014 Pazartesi 20:42:33 UTC+3 tarihinde Eren Basturk yazdı:

[Jakob Flierl]

吳政昌 is has built a BeagleBone variant called BotBone with two NICs suited for EtherCAT master/slave.

More info at:

* https://docs.google.com/document/d/1X9RrbkUpiTQ-S6Acken-5fv7yYq2DTr_1zOjf6zabn0/edit#heading=h.fxx7nvltcl7x

* https://plus.google.com/109948108631535499425/posts/jLJbwwJrLgP

* http://www.mapacode.tw/

- Jakob

[Jakob Flierl]

Hi,

I was playing with Machinekit + EtherCAT Beckhoff hardware last week.

I just finished most parts of the docs of my hardware and software setup:

https://github.com/koppi/mk/blob/master/Machinekit-Xenomai-Thinkpad-X200.md

- Jakob 

[John Morris]

Wow, very cool, doc looks great. I'll spend more time with this later.

Are you using the 3.8.13 kernel, as the doc says, or 3.18.12, as the
kernel oops screenshot says?

I actually ended up rebasing my package modifications onto the Debian
3.16.7 kernel last night (haven't even tried building yet). The latest
ipipe patch in the Xenomai 2.6.4 release is 3.14.17, and there's a
3.16.7 patch in 3.0rc. I don't see anything newer.

John

[Jakob Flierl]

2015-05-15 20:24 GMT+02:00 John Morris <jo...@zultron.com>:
> Are you using the 3.8.13 kernel, as the doc says, or 3.18.12, as the kernel
> oops screenshot says?

The oops screenshot is from an experiment with Kernel 3.18.12 and Xenomai 2.6.4.

I just removed the oops screenshot from my docs, as I made the mistake
to enable ACPI during the kernel configuration step.

> I actually ended up rebasing my package modifications onto the Debian 3.16.7
> kernel last night (haven't even tried building yet). The latest ipipe patch
> in the Xenomai 2.6.4 release is 3.14.17, and there's a 3.16.7 patch in
> 3.0rc. I don't see anything newer.

I followed these instructions:
https://xenomai.org//2014/06/building-debian-packages/
and used ipipe-core-3.18.12-x86-1.patch from the Adeos repos at
http://download.gna.org/adeos/patches/v3.x/x86