Re: [CAD_CAM_EDM_DRO] Re: Re: Was Chopper circuit - Now ver 3.2, G298

You missed it. Read the rest of that post. It stated:

> > I'm in the middle of a project that uses a PIC to drive a 3776.

It uses

> > simple 2% resistors to generate 1/2 - 1/4 - 1/8 steps. No DAC

required.

Those resisters smell just like a DAC to me ;-)

Regards,

Paul R. Hvidston, N6MGN
ACKSYS Engineering
Upland, CA

----- Original Message -----
From: "scottdbtnet" <scott@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Friday, April 26, 2002 3:06 PM
Subject: [CAD_CAM_EDM_DRO] Re: Re: Was Chopper circuit - Now ver 3.2, G298


> Paul-
>
> I can accept that a comparator is a crude A to D, but D to A?
>
> --- In CAD_CAM_EDM_DRO@y..., "Paul R. Hvidston" <paulh@u...> wrote:
> > Scott-
> >
> > But that _is_ a DAC ;-)
> >
> > Paul R. Hvidston, N6MGN
> > ACKSYS Engineering
> > Upland, CA
> >
> > ----- Original Message -----
> > From: "Scott M. Thomas" <scott@d...>
> > To: <CAD_CAM_EDM_DRO@y...>
> > Sent: Friday, April 12, 2002 6:36 AM
> > Subject: RE: [CAD_CAM_EDM_DRO] Re: Re: Re: Was Chopper circuit -
> Now ver
> > 3.2, G298
> >
> >
> > > I have even seen PIC's with comparators built in!
> > >
> > > -----Original Message-----
> > > From: Alan Rothenbush [mailto:beer@s...]
> > > Sent: Tuesday, April 09, 2002 9:05 PM
> > > To: CAD_CAM_EDM_DRO@y...
> > > Subject: [CAD_CAM_EDM_DRO] Re: Re: Re: Was Chopper circuit - Now
> ver
> > > 3.2, G298
> > >
> > >
> > > >
> > > > Why bother with a PIC for a L297 replacement, unless you wanted
> to add
> > > some
> > > > rudimentary microstep capability? Would a PIC be cheaper? The
> L297 can
> > do
> > > > half-step and full-step, but adding microstepping would require
> a DAC
> > and
> > > > control logic.
> > >
> > > I'm in the middle of a project that uses a PIC to drive a 3776.
> It uses
> > > simple 2% resistors to generate 1/2 - 1/4 - 1/8 steps. No DAC
> required.
> > > This would be an add-on for DanM's 5A controller.
> > >