Re: Remote DRO

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "mlaws1172" <mlaws1172@...> wrote:

>
> I am not questioning Mariss design (remote Dro) but trying to end a
> small bit of my ignorance. Can the same basic thing be done with some
> sort of non-inverting gates?
> mike
>

Mike be careful with interfacing the motor encoders running from a
Gecko and the inputs to a PC. Here is the deal: The Gecko has an
internal buss that is referenced to the motor neg. Thus Enc - is at
the Motor DC negative and Enc + is at the +5 inside the Gecko. If
your PC ground is not referenced to the motor neg(i.e. they share the
same ground) then you can easily pop the gecko logic card or your
parallel port. If your parallel port has opto isolated inputs through
an isolated breakout, then you need to make sure the ground for the
opto inputs is referenced to the motor neg. The Gecko's have opto
inputs so you don't have to share the noisey motor ground back to the
low level logic and PC ground.

It's not a buffer problem it is a voltage level and noise issue.