> Am 27.10.2009 um 14:21 schrieb christian bazungula: > >> Hello Dave, >> >> Thanks too much for your answer. I'll check out Modbus and after >> i'll let >> you know. >> >> To answer to your question, i'm trying to see if there is a way to use >> fieldbuses in communication between EMC2 and machine. This is to >> reduice the >> wiring between them. > > This will also increase latency and introduce queuing delays. So > there's a limited range of options what you can actually drive over > such a bus, in particular a slow one like Modbus - sureley nothing > with hard realtime requirements. > > so far Modbus drivers have been used to control spindle VFD's, and > even here some operations have a feedback loop (like "spindle at > speed"). > > Maybe SPI is an option. Either way, count wires before and after the > bus exercise..
There was some work beeing done with EtherCAT, however I'm not sure how well it's working. It should (in theory) be fast enough to update servo motors too. There are at least 2 EtherCAT master open source implementations which could be used with emc2, but you get stuck with using EtherCAT slaves (hardware). I think the fieldbus question is best answered by first looking at the drives/hardware one wants to use. Regards, Alex ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
