Re: [CAD_CAM_EDM_DRO] EMC Lathe mode.

Art Fenerty wrote:

> Hi Jon:
>
> From the software's point of view, I think one pulse would do. Afetr all,
> the spindle is not changing speeds fast enough to disturb the mathmatics.
> If you time the distance between pulses, you can figure out where the
> spindle actually is at all times I would think.

No, completely wrong, assuming you are hooked to an encoder counter.
In between pulses, you have no idea what part of the revolution you are
in. The only way this would work is if the computer's interrupt was
synchronized to the spindle pulse. But, one interrupt per revolution would
be totally inadequate. You would need to have a synthesizer that produces
a roughly constant number of interrupts per second, but would reference
every N ticks to the spindle pulse. Sounds like a nightmare!

If you use a spindle encoder and encoder counter, then you have no
idea where the spindle is, you only know that it is somewhere in the
Nth revolution. You can't sync the Z axis to that. You need much finer
feedback.

Jon