I've been around for a while and worked with current loop serial interfaces, rs232, rs422/485, Ethernet (back when thicknet was standard) etc.
Why in world would you not use Ethernet?? It leaves you with so many options that are not available with RS485. I would join the Ethercat group, pay them some $$, get some source code and use what has already been developed and use every tool that they have already developed. No need to reinvent the wheel. Dave On 6/6/2015 4:19 PM, Philipp Burch wrote: > Hi everyone, > > when we're talking about buses and interfaces, I'd like to bring up > another topic concerning me recently: We're building some kind of PLC > and motion controller mainly for internal uses, which is built around > FPGAs. Our FPGA configs are crafted specifically for what the devices > need to do, so there is no softcore or other microcontroller around. We > now have a simple serial interface connecting multiple boards using > differential pairs (RS-485-like) for RX and TX, transmitting frames of > some 64 bits each. This works, but is obviously completely proprietary. > > Hence the question: Are there standard interfaces (call them buses if > you like, I don't mind) of similar complexity with open specifications > around? I personally like the idea of the summation frame method > (Summenrahmenverfahren in German) as is used by EtherCAT, but this > interface is overkill for us and also not "open" unless you are some > kind of "member". I found Interbus which seems to fit quite ideally, > but, again, is not as open as I'd like it to be and it also looks to be > kind of obsolete. > > Rough requirements would be: > - Usable for daisy-chaining (no common bus) > - Data rate somewhere in the range 1Mbps .. 10Mbps > - Serial with exactly one RX and one TX pair in each link > - Suitable for deterministic cyclic transfers with some tens of bytes each > > Any ideas, hints, comments? > > Regards, > Philipp > > > > ------------------------------------------------------------------------------ > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
