[etherlab-users] Question on real time (newbie)

[Richard Hacker (MSc Eng)]

Hi Antonio,

Embedded in the EtherCAT Master is a cyclic part and a state machine part. The 
master state machine executes in a separate thread and does not require real 
time functionality. The cyclic part does not use any kernel features that can 
cause it to lock.

Other than the examples, there is also no dependency on any real time calls, 
be it Xenomai, RTAI or whatsoever.

So, you can use it for your real time applications just as we do.

Richard

On Tuesday 05 May 2009 18:23, Antonio Del Cinque wrote:
> Hi,
> I'm really new to the EtherCAT Master, so please forgive if the question is
> odd or old.
>
> I am working on the MPC5121e SoC from Freescale (PowerPC e300 Core).
> Freescale delivers a Linux BSP, with a 2.6.24.6 kernel and patches
> including early SoC device drivers. To enable real time tasks, after
> considering RTAI and Xenomai as solutions, I deployed Xenomai, because of
> better support for the PowerPC arch. I guess there is no port of the
> EtherCAT lab to Xenomai, so maybe I should reconsider RTAI...
>
> Anyway browsing through the sources, I see that the ethercat master module
> is using plain calls to Linux services when executing the master state
> machine. I don't know RTAI details, but I see it uses a co-kernel approach
> for real time, similar to that used in Xenomai, so that, even when master
> code is executed in an RTAI task, Linux service calls would prevent real
> time to be guaranteed.
>
> Is the ethercat master guaranteed for real time?
>
> Antonio

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Richard Hacker
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