Re: [CAD_CAM_EDM_DRO] Help in understanding Microstep table

Looks like the LSB is the sign bit, so it has 4 bits for the DAC, then
there is a sign bit, so you have 16 positive values, and 16 negative
values. The other bit is what they're calling "mixed decay." Not sure
what's going on with that other than the comment in the source.
So, let's see, 16 counts up the slope of the sine wave, then set mixed
decay, 16 counts down the slope, change the sign bit, clear mixed
decay, 16 counts down the negative slope, set mixed decay, 16 counts up
the negative slope, which brings you back to 0. So, that's 64 counts.

Regards,
JJ

On 12-Sep-2005, at 18:02, Joaquim Boavida wrote:

> Hi, all
>
>
>
> I'm trying to develop a step motor controller using trinamic chips.
>
> (www.trinamic.com <http://www.trinamic.com/> ).
>
> So far I understood everything, but I have a doubt about a microstep
> table.
>
>
>
> Source example is here ->
> http://www.trinamic.com/tmcweb/downloads/tmc236_example_MD.c
>
>
>
> This chip as a 4 bit DAC, thus a 16 micro step resolution. So, why is
> the
> table 64 positions?
>
> Should be only 16 right? I believe that this as to do with the sin/cos
> functions. That means
>
> That this table is a complete sin/cos function (16*4). If this is
> right how
> do I move one
>
> full step using only 16 microsteps (in the max resolution) ?
>
>
>
> Boy I'm confused.
>
>
>
> Thanks in advance
>
>
>
> Joaquim
>
>
>
>
>
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
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