Am 10.11.2010 19:59, Vinzenz Bargsten wrote: > Am 10.11.2010 18:51, schrieb Anders Blomdell: >> On 2010-11-10 18.23, Vinzenz Bargsten wrote: >> >>> Hi, >>> >>> can someone provide (more) information on how to run a RTnet >>> in combination with in this case one non-Linux/non-RTnet, i.e. windows >>> machines? >>> >>> The windows machine (robot controller), which runs some proprietary >>> real-time >>> software, >>> sends a UDP packet with XML strings every 12ms to the Linux machine. >>> The Linux machine receives and processes the data (<1ms) and has to answer >>> in >>> less than 12 ms. >>> >>> At the moment,the setup on the Linux machine is: >>> kernel 2.6.32-7 x86_64 with xenomai 2.5.1, RTL8139 NIC >>> The data processing is done in/via OROCOS in a real time task. >>> There is no other machine on this network. >>> >>> However, the problem is that the real time requirement is not met, >>> i.e. the answer from the linux machine sometimes takes more than 12ms. >>> Using wireshark we found out, that normally the answer is sent after (packet >>> receive time) + ~0.5ms, >>> but after some time (minute(s)), it takes>40ms and several/the missing >>> packets >>> are sent at once. >>> >> Could it be that you are running a SMP machine? Then this might be of >> interest: >> >> https://mail.gna.org/public/xenomai-core/2010-11/msg00053.html >> >> later kernel, but the bug might exist in earlier versions (Jan can you >> comment >> on this)? >> >> > > > to clarify it: > I don't use RTnet yet, i.e. the interface uses the normal kernel module and I > want to use RTnet because these problems occur.
Ugh, then it's obvious that you see such huge latencies. This cannot work as it breaks the real-time chain. > I am just not sure how to use RTnet with non-RTnet/tdma remote machines. See the documentation, there is an explicit section about basic, RTmac-less setup. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux ------------------------------------------------------------------------------ The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev _______________________________________________ RTnet-users mailing list RTnet-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/rtnet-users
