Re: [CAD_CAM_EDM_DRO] stepper encoders

At 17:57 12/2/2002 -0500, you wrote:

>In a message dated 12/2/2002 12:16:26 PM Central Standard Time,
>mmiami2002@... writes:
>
>
> > All I realy know is the pin outputs +vcc, gnd , ch a, ch a not, ch b, ch b
> > not, index, index not.
> >
> > Could someone explain the basics of hooking up these connections?
>
>
>Troy: I have been reading about encoders and "feedback" on machine-control
>for years (and gave up and stuck with steppers with great success!), so I can
>tell you about these connections, though surely some others "in here" like
>Mariss or Jon could do so much more eruditely:
>
>"+Vcc" means the Plus DC supply, PROBABLY 5.0 VDC. Gnd is "common" to DC and
>all outputs. There are "three outputs", Channels A and B, and Index. The
>"Not" for each is simply the INVERTED version of that output. For example,
>if "A" is HI, then "A not" would be LO, and vice-versa. SOME counters "want"
>inverted inputs, and I suppose some might be configured to "want" both, but I
>can't imagine why!

The inverted outputs are part of what makes a "differential output"
encoder. Both signals are integrated with a comparitor at the computer end
of things to cancel out electrical noise...very common in commercial CNC
machine tools.

-Bob