So Sebastian's suggestion works without a problem. Thanks! With a 100Khz servo period things work fine.
Before that I was making progress when I started setting the stepgen max accel, and max vecloity. Basically the systems starts to resemble a servo system at that point. I think to make it work properly, a veclocity mode pid controller would need to go in between the motion component and the stepgen. Because the servo period boost is sufficient for my needs, of course I will just use that, however for future reference it seems that one can run hostmot2 at a higher speed. On Tue, Feb 7, 2017 at 4:09 PM, Peter C. Wallace <[email protected]> wrote: > On Tue, 7 Feb 2017, Curtis Dutton wrote: > > Date: Tue, 7 Feb 2017 15:55:32 -0500 >> From: Curtis Dutton <[email protected]> >> Reply-To: "Enhanced Machine Controller (EMC)" >> <[email protected]> >> To: "Enhanced Machine Controller (EMC)" <[email protected]> >> Subject: Re: [Emc-users] calling hm2_<BoardType>.<BoardNum>.write + >> hm2_<BoardType>.<BoardNum>.read at higher rates >> >> That is where I'm at right now. My base thread is limited because the >> > feedback from hostmot2 only changes at servo rate, and it only updates the > pwmgen at servo rate as well. > > So computing the output value of the pwmgen at the base thread speed is a > waster of effort.. > > If I could read and write hostmot2 faster it would work, but it appears it > is not designed to do so. > > The hostmot2 read and write time's are short enough to work with a base > thread of 50 us, but there must be something in there that is assuming the > servo period is 1000 us. > > > > Not really, 8KHz servo threads are possible on fast PC hardware > > The best way to do this with Mesa hardware would be data painting > firmware/driver/interpreter > > > > > On Tue, Feb 7, 2017 at 3:44 PM, andy pugh <[email protected]> wrote: > > On 7 February 2017 at 18:28, Curtis Dutton <[email protected]> wrote: >> > As part of my laser engraver implementation that I have been working on, >> I >> > have a raster component that needs to vary the pwmgen output at higher >> rate >> > than the servo period. >> >> I don't think you can vary the pwm duty cycle any faster than the >> servo thread rate. >> The duty cycle calculations are performed in a floating point thread, >> the base-thread function runs at a constant PWM rate between >> duty-cycle updates. >> >> It is actually possible to run floating-point base-threads, but then >> you will find that the component that determines the duty cycle would >> also have to run in that faster thread. >> >> Maybe you could run three threads? >> >> -- >> atp >> "A motorcycle is a bicycle with a pandemonium attachment and is >> designed for the especial use of mechanical geniuses, daredevils and >> lunatics." >> яя George Fitch, Atlanta Constitution Newspaper, 1916 >> >> ------------------------------------------------------------ >> ------------------ >> 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 >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users >> >> ------------------------------------------------------------ > ------------------ > 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 > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > > Peter Wallace > Mesa Electronics > > (\__/) > (='.'=) This is Bunny. Copy and paste bunny into your > (")_(") signature to help him gain world domination. > > ------------------------------------------------------------ > ------------------ > 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 > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
