RE: [CAD_CAM_EDM_DRO] stepper pulser, and RE: Stepper driver question (slightly O.T.)

> [mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of Richard L. Wurdack
>
> There may be logic states that you want to accomodate as well that are
> simple in a PIC but complicated in a BEAM type control - such as power up,
> power down, and various failure modes such as simultaneous true from both
> sensors.
>
> Alan,
>
> I have been considering a similar device using a PIC to the one you're
> working on. (One of my applications is a Solar array tracker.) Please let
> me
> know when you have a design.
>
> Thanks,
>
> D.
> ----- Original Message -----
> > HI Dave, Marv,
> >
> > You're right! The 555 timer circuit posted in the files could ramp a
> > stepper up. Add comparators, and you might have it.
> >
> > But just changing directions may not be enough. Some hysteresis may be
> > required, so that the device does not "hunt". How wide would the "dead
> > band" (area between limits where no motor activity is desired) be? I
> > suppose if a "limit" (photo detector, what type?) was reached, one could
> > simply move 1/2 the distance across the dead band.
> >
> > Contact Dave or I off list if you're interested in a PIC solution. Dave
> and
> > I are currently working on a "stepper pulser" that runs a stepper with
> > proper acceleration/deceleration in either direction when a switch or
> push
> > button is actuated. Your project doesn't sound like a big leap from
> ours.
> >
> > A stepper driver would be required; an LMD18245 stepper driver would
> work,
> > or you could order a single axis Xylotex board. The ELS board (ELS
> list)
> > would be a candidate; it has a driver on board. Also has an LCD
> display,
> > which may or may not be desired.
> >
> > Our stepper pulser board is smaller, and may be used with or without an
> LCD.
> >
> >