Re: [CAD_CAM_EDM_DRO] Parallel Port Interface

Hi Gary,

What do your drivers have? If they already have opto's, you don't need
to add them! Some parallel ports may need a little pullup for the limit
and probe sense switches. I like to use a BRAVO Communications Parallel
port Extender to provide some isolation and protection with MaxNC's
4-phase driver board.

HTH

Alan KM6VV


Gary.Rose@... wrote:

>
> Hi,
>
> I'm putting together a small cnc system (Sherline based) and am at
> the point where I'm thinking about how to connect the parallel port
> to the stepper drivers, limit switches, manual jog controls, etc.
>
> Some schematics that I've found on the web show the step and
> direction and other lines directly connected to the parallel port,
> others use optoisolators (4N33 for example), others just have pull up
> resistors, still others use buffer gates.
>
> Any thoughts? I'm leaning toward optos, because that's what I know,
> but what do you guys think? Is it worth the trouble or not?
>
> Thanks
>
> Gary