On Saturday 25 November 2017 08:21:07 Gene Heskett wrote:

> On Saturday 25 November 2017 05:59:19 andy pugh wrote:
> > On 25 November 2017 at 03:36, Gene Heskett <[email protected]>
>
> wrote:
> > > But sitting here thinking as I edit the hal file, (I can get into
> > > all sorts of trouble doing that) the encoders position value is
> > > determined by the existing scale factor I believe
> >
> > Do your gear ratio calcs based only on counts.
>
> If index-enable is true, (it is) which ack the man page:
>
> encoder.N.index-enable bit i/o
>               When  true, counts and position are reset to zero on the
> next rising edge of Phase-Z.  At the same time, index-enable is reset
> to zero to indicate that the rising edge has occurred.
>
> Which because I want the total counts, I should use rawcounts which is
> not reset? Thats what I have it coded for atm anyway, but I've not yet
> added an updown for the Z counter. Working on that now.
>
> Thanks Andy.
>
> Cheers, Gene Heskett

Got that running, using rawcounts, but I am not getting an integer number 
for an answer. 14,095.11 for low gear. And 7,161.26 for high gear. This 
is for 100 turns of the spindle, which is indicating a hair over 100 
rpms on the uncalibrated tach with the scales set at a value between 
those answers. One comparator set for 5.5, the other set to lock its 
mux2 at 105.5 The mux2.outs are fed to a sum2, with the one that stops 
at 5.5 set for a gain of -1.0000000 so its a subtraction at its output.  
That frozen value is then fed to kcalc and /100 for the above values.
Looking at the 3 signals with halscope, triggered on the same rising edge 
of the z pulse, which is the end of it, the servo-threads quantization 
because of it nominally 1 kilohertz period, doesn't have a fixed phase 
relationship with the a/b signals. Trying again with the spindle just 
creeping along at 25 or so rpms. And get 7161.24 for high gear, and 
14,095.23 for low gear.  So it seems repeatable to a very small fraction 
of a %.

What conclusion would you reach based on the above? Other than ripping 
out the opto's on those 2 input channels of the bob.

Speaking of opto's, SainSmart seems to have a micro sized board, with led 
input tallys and 24 mill buffering but without mentioning opto anyplace 
in the propaganda on amazon, for $18/copy. I may wait till Monday and 
see if I can confirm the lack of optos as being a plus.

If useing these things, where can the individual cables be obtained, the 
ones that fit the white sockets on these boards? That would simplicate 
the hookup for sure.

See at:
 
<https://www.sainsmart.com/products/cnc-5-axis-breakout-board-for-stepper-motor-driver?utm_medium=cpc&utm_source=googlepla&variant=45099994132&gclid=EAIaIQobChMI5tqQgY7a1wIV0LXACh19Nwm5EAQYAiABEgJ9OvD_BwE>

Is anyone here using it? Its been around since 2012 it seems.

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)
Genes Web page <http://geneslinuxbox.net:6309/gene>

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