Re: General Question REgarding Stepper vs. Servos

Hey Tim, I AM running a DOS program through WinXP without errors -
no program errors, no machining errors. I have access to my
parallel port, the encoder and the motors. I believe, but am not
absolutely sure, that a closed-loop system is a necessary part of
this type of setup. Refer to message 62087 and subsequent threads.
Thanks Charles

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Tim Goldstein" <timg@k...>
wrote:

> > -----Original Message-----
> > Daniel,
> >
> > Let me preface this by saying I'm not an expert and basically

going

> > off of what I'm learning here.
> >
> > I believe I want closed loop. Stepper or servo not an issue I

don't

> > think as far as accomplishing the cut. I want closed loop since

I

> > want to run off of DOS emulators and not true DOS of the higher

O/S,

> > therefore I am less worried about any missed steps creating a
> > possible tolerance stack in a long routine.
> >
> > Charles
>
> Closed loop on a stepper is mostly a marketing ploy in my mind. AS

far

> as running DOS programs on any of the NT based operating systems
> (Windows NT, 2000, XP), you can't. It is not just a timing issue,

but

> the fact that these systems will not allow direct hardware access

by the

> programs. So, they error and fail when they try to write to the

parallel

> port. If you want to use any of these operating systems to drive a
> machine you have to use a controller program that is designed to

work in

> them. Your choices are Mach1 or 2, Flashcut, DeskCNC.
>
> Tim
> [Denver, CO]
> Sherline products at Deep Discount
> Mach1 & DeskCNC with credit card ordering
> www.KTMarketing.com/Sherline