> >> ... It looks like it might > >> be easier with the uspace / rt-preempt kernel than with > >> rtai. It would reduce latency/jitter to ns levels.
If you build the system so that within servo period is OK things will get a lot easier and will fit with ordinary theory fo real time scheduling, dead time equal to period. > Yes, actually, it WOULD. All the Pico Systems motion > control boards can latch the position when the internal > timer ticks. ... This is the way to do it. > ... > The master board sends the latch command on the parallel > port bus to other boards on the bus, as well as the > computer. The computer would have the luxury of responding > before the next timer tick, nominally 1 ms. This is a good way to get it synchronized a hardware 1kHz signal and the full 1ms period left for software jitter software. > As long as the computer never took more than the timer > period to complete its work, it would never cause ANY > latency at all! The computer's updated velocity info would > not become effective until the next timer tick. Then you use EDF or rate-monotonic scheduling it will make a perfect fit with the theory. > Jon ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
