In EthernetIp tcp is used for non critical data such as parameters and to set what the contents of the UDP packets are.
I can only control the EthernetIP implantation on my device. Thanks, Glen -- Glen Wernersbach President & CTO Jetsoft Development Co 629 Old St. Rt. 74 - Suite 210 Cincinnati Ohio 45244 Custom Programming Web Site: www.JetsoftDev.com Retail Product Web Site: www.ScanHelp.com Phone: 513-528-6660 Fax: 513-528-3470 On Sep 28, 2010, at 5:35 PM, Jan Kiszka <[email protected]> wrote: > Am 28.09.2010 23:17, Glen Wernersbach wrote: >> Jan, >> >> My basic concern was to keep the data flowing from the NIC to my program as >> close to hard real time as possible. I know doing Linux calls can break hard >> real time especially when I want to receive a UDP packet every 1ms. > > Is that UDP packet part of your control loop? Why do you need the whole > opener stack then? Or is there more? > >> >> The only thing Ethernet IP really gives you real time is optional support >> for the Ethernet 1588 timing standard so you know what the jitter was in >> receiving the packet over the Ethernet line. The 1588 support is not yet >> implemented in opener. The rest is just a protocol for handling critical >> data over TCP and UDP. Unfortunately, I have a device that needs to work on >> Allen Bradley controllers which only support this real time protocol. >> >> All I want to do is replace the Linux calls in networkhandler.c >> (socket,bind,listen...) with RTAI real time calls. > > Additionally, you will have to configure the socket resources, namely > how many buffers each socket should pre-allocate for its real-time > operation (that's the major difference to normal networking stack that > do on-demand allocations). See the examples. > > Jan > ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ RTnet-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/rtnet-developers
