[etherlab-users] callbacks with CoE

Erwin Burgstaller ethercat.berknapp at spamgourmet.com
Tue Oct 6 09:18:26 CEST 2009

* Mon, Oct 05, 2009 - 16:57:39 +0200, Edgar Garzon - edgarcgarzon at gmail.com:
> I'm just want to know if is necessary use the callbacks when I'm
> implementing and CoE protocol. If I'm using CoE there are somewhere a
> concurrent master use? or I just could ignore it? if there concurrent use of
> the master which other instance are trying to access the master that isn't
> be my application mode? I'll be very grateful if you could give me short
> explanation.

Yes, you have to implement that callbacks. Without them EoE will not
work, as the master handles this alone, but needs exclusive access to
the bus.

Up to masters version 1.4 you just have to grant access and you have to
take care the master and your event loop are not doing send and receive
requests at the same time. So you have to use semaphores to handle that.

In the latest development release, you'll have call send/receive
operations when requested by the callback. I already wrote some
questions about that to the developer mailing list, but Florian Pose
seems to be out of office since 2 Month or something like that. In fact
he doesn't answer to the mailing lists anymore.

But you could just take the rtai example which comes with the masters
source code. Yours should just work pretty exactly that way.


Erwin Burgstaller

More information about the Etherlab-users mailing list