I'm sorry my replies are fragmented, but i have problems in setting gmail for a different e-mail address out... Long story.
> >I have a tech question about 7i92. I have only run Lcnc using software step >gen, but I understand that a 7i92 does step generation on its own, freeing >the pc from doing the hard work. But what messages are sent from the pc? are >they just POS/SPEED? and, since I have my untrivial kinematics, are they >always done by the pc, right? Yes, speed sent, current position returned, all position/velocity calculations done in LinuxCNC, but if you can get the desired step rates from your parallel port, you may not need a 7I92 and just need differential drivers at the BOB end for the paralle port generated step/dir signals The bob i'm using now is the keling c35, which gas buffered TTL outputs. Maybe, since I need very High step rates (i need to reach almost max speed out of these hybrid nema34-12NM steppers) i'm thinking about going with 7i92. I've read the manual and there's not the possibility to set them for differential output, am i right? In case i can build a simple rs422 bob. > >when I run a latency test I have good results, something like Servo t. 2-3000 >and Base t. 5-7000. Is the 7i92 driver linked to the Servo, or Base Thread? >what Latency time is it needed? and for 4*7i92? > The 7I92 uses a servo thread only and requires a Preempt-RT kernel (the Stretch test ISO is the easiet way to do this) Yes, right now i have stretch with preempt-rt on, with lcnc 2.8. Peter, please can you confirm 7i92 works OK with latest 2.8? And, just in case i'll feel more confortable in using one 7i92 per winch and ethernet/optic fiber converters for the long range, i know 4 of 7i92 are really oversized, but can you confirm they can work together without slowing down everything? Thanks, Davide. _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
