i understand what andy said, maybe that's right.
> On 20 August 2015 at 02:39, Jullian <[email protected]> wrote: >> but i still cannot catch the point. > > Let me try. > > The step generator maintains an internal counter of steps sent. I > think that this is 64 bits. > The step generator position is this count divided by the stepgen > scale, as floating point. > > The motion controller does not send moves, it sends positions. (as > floating point). > > The step generator converts a newly-sent position command to a total > number of steps, compares that to the count of steps already sent, and > either steps up or down to the new step count. > > So, the calculations are all absolute (from wherever the motors are > when the machine is turned on, but the homing offsets deal with that) > rather than incremental, so there is no accumulation of error. > > -- > atp > If you can't fix it, you don't own it. > http://www.ifixit.com/Manifesto > > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers > ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
