Re: [CAD_CAM_EDM_DRO] EMC signal output

Cryo wrote:

> I didn't find any documentation about EMC's port settings.
> Can I change step/dir signal polarity easily somewhere?
> My driver needs signal which is normally down and when step coms is
> up.
>
> Another thing is timing. Can I change pulse width and other that kind
> of stuff somewhere?
> I need signal which is like this:
>
> step |---| |---|
> ----| |-------| |----
>
> dir |-------| |-------|
> ---| |---| |-
>
> I put oscilloscope to EMC output and it's like:
>
> step |---| |---|
> ----| |----| |----
>
> dir |------------|
> ----| |----
>

I don't see the problem here. It should be legal for the direction
signal to stay at the same polarity if two consecutive steps will be in
the same direction. The only concern is that the direction signal does not
change too close to the active edge of the step signal (which can be the
rising or falling edge, depending on the step driver).

The polarity of the step signal is also not generally important, except
for the relationship to changes in the direction not ocurring too close
to the active transition.

My parallel port step rate generator does allow the width of the step
pulse, as well as the setup time delays around the active edge of the step
signal to be controlled. I will probably put polarity switching logic
in the final version of this.

Jon