On Thursday, 28 April 2022 21:17:20 EDT gene heskett wrote: > On Thursday, 28 April 2022 19:35:44 EDT andy pugh wrote: > > On Fri, 29 Apr 2022 at 00:20, gene heskett <ghesk...@shentel.net> > > wrote: > > > > Surely you already know that? It's 360 x 100 x SCALE ? > > > > > > Sure Andy. But what is the scale? > > > > 200 * 16 * 40 * (60/53) / 360 > > But these motors are not 200, but 300, they are 3 phase, 1.2 degrees a > full step. 300 steps per rev for full step. > > So by purely mechanical means, that would then be: > 300 * 16 * 40 * [60/53] / 360, or 603.7735849 according to my TI-36X > Pro. But thats about 5x what seems to be pretty close @ 125.xxxxx. > > Something, someplace is lying like a rug. But where? You got the hal > file now, is it wrong? Two problems to fix before its right.
1. These drivers have two microstep modes, digital and apparently powers of 10. Only one switch is on, sw3, which claims it makes a full turn of the motor in 6400 steps. Just one problem. A 300 full step per turn motor cannot be made to equal 6400 with any integer multiplier. At /16, its not 6400, but 4800 steps per turn. A value that's off either by .75, or 1.333333333333 depending on interchanging the numbers. If it is truely actually 6400 microsteps/turn, what the hell kind of math is it useing? Obviously NOT a power of 2. I think these little magic boxes are miss- marked. Obviously whoever drew up that silk screen was thinking in terms of a 200 full steps per turn motor, and the 3 phase models are 300, not 200. So that means 300*16 is 4800 steps per turn of the motor shaft. No way in hell can I make the math work using thier silk screened figures. So that's problem #1. And the correct answer can only be found if #2 is a 1/1 answer. [edited] > I just found the stepgen drawings in the docs and I think my hal file > is wrong, the values presented by the position.fb pins are not in the > same units as .count's. position.fb has been scaled. 2. The $64k question then, since the step itself is not available to hal for counting, is the stepgen a direct translator?, issueing 1 full step per count it reports on the .count pin? (yes/no) If no, what is the ratio? > And this needs counts. I'll fix that when I get it back together. Then > maybe it will make sense. > currently stepgen3.counts is -173640, > while stepgen3.position.fb is 1380.7 Fixed already, but not yet exersized for truthfullness. A sneakernet mistake. :o( Thank you, Andy. Cheers, Gene Heskett. -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author, 1940) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
