On 23 April 2010 17:12, Schooner <[email protected]> wrote: > loadrt encoder num_chan=1 > addf encoder.update-counters base-thread > addf encoder.capture-position servo-thread > setp encoder.0.position-scale 1 > net spindle-position encoder.0.position-interpolated => motion.spindle-revs > net spindle-velocity encoder.0.velocity => motion.spindle-speed-in > net spindle-index-enable encoder.0.index-enable <=> > motion.spindle-index-enable > net spindle-pulse-and-index parport.0.pin-11-in => encoder.0.phase-A > encoder.0.phase-Z ;set to correct pin. " > > /I am afraid I do not understand how encoder.0.phase-Z could be > connected to anything, there is only one index pulse.
You can use the same p-port pin to drive more then one "logical pin" in HAL. In this case you need to link the encoder A-phase to your pin-11 so that EMC can calculate a spindle speed, and also the Z-phase (which is the index pulse) to the same pin. > I included the above into my .hal minus the last line. You need the last line. Note that it is actually part of the line above but has line-wrapped. There is another troublesome wrap in the index-enable line. > If I rotate the spindle manually, I get a positive indication every rev, > so maybe the hal monitor > display just cannot update quickly enough. HAL monitor doesn't, know. For transient signals you should use Halscope, it works a lot better. It is one of the most useful tools in EMC in fact. It is in the same menu as the Hal Config and Hal meter. > Have I missed something or is the answer that you cannot thread with > just an index pulse and you must have a timing pulse too, connected to > encoder.0.phase.Z perhaps?? Yes, you need both, but they can be from the same pickup and the same parallel port line. Incidentally, I think you have speed and no index rather than the other way round. I think you might also need to add a line: setp encoder.0.counter-mode 1 to the HAL to tell it to not look for the B-phase. Details here: http://www.linuxcnc.org/docview/html//man/man9/encoder.9.html > Would my 4 magnet set-up through a second pickup provide that, if a > timing pulse is required , or is that too coarse? More pulses is better, but a few inaccurately-times pulses is probably worse than 1PPR for introducing errors to the spindle velocity calculation. -- atp ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
