I think we're actually all saying about the same thing. A controller like a PC or a Pi3 needs some sort of external hardware that can deal with high speed quadrature encoders. Whether it's done with a STM32 or FPGS doesn't really matter for the sake of discussion. Meanwhile, as Jon reiterated, the BBB has the dual 200MHz PRUs that share memory and I/O and therefore can work with the Beagle main processor much more efficiently. So although internal, it's still really a separate processor (sort of)... John Dammeyer http://www.autoartisans.com
> -----Original Message----- > From: Nicklas Karlsson [mailto:nicklas.karlsso...@gmail.com] > Sent: March-10-19 1:25 PM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] STM32 Blue Pill --> distance between pins > > > > ... > > Jon, > > You make a very good point. Why bother, with the new 32 bit controllers > that do so much even bother with the antiquated idea that the LinuxCNC PC > should close the loop on positioning. Running encoders from a servo motor > back into the PC to some sort of controller board that creates +/- 10V out is > now not really a good option. > > To locally close the control is the best option and the method I use. Values > sent for position and encoder values are still the same but I do not have a > PID. > > If a +/- 10V signal is used with local feedback there will be nested control > loops which may add problems but local speed control loop and linuxcnc > position control loop might work well. Analog signals may have a high > update rate. > > > Nicklas Karlsson > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
