On Fri, 1 Jan 2016, andy pugh wrote: > Date: Fri, 1 Jan 2016 16:59:12 +0000 > From: andy pugh <bodge...@gmail.com> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] Smart-Serial cabling > > On 1 January 2016 at 16:16, Peter C. Wallace <p...@mesanet.com> wrote: >> SSerial is differential RS-422 at 2.5 MBits/sec and requires ~100 Ohm >> differential cable cable impedance. This usually means twisted pairs >> are required for TX and RX (the 5V/GND power connections are not critical) > > The pairs are twisted inside the individual foil screen with drain > wire then there are 4 other small (0.14mm2) wires and two bigger > (0.5mm2) wires all inside an overall braided screen. > > I suppose the thing to do is to try it and see. I have determined that > the pairs fit nicely in an RJ45 connector, but I can't decide what to > do about the 2x 5V and 2x 0V positions in the connector. Are the 0V > and 5V contacts commoned at the PCB ends, such that leaving two > positions unpopulated in the RJ45 is OK? I only need enough 5V power > to run the 7i73 logic.
Yes, they are commoned at the sserial remote and FPGA side RS-422 interface > > -- > atp > If you can't fix it, you don't own it. > http://www.ifixit.com/Manifesto > > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
