CAD CAM EDM DRO - Yahoo Group Archive

RE: [CAD_CAM_EDM_DRO] Phase vs. Step/Dir?

Posted by Tim Goldstein
on 2003-08-24 11:27:00 UTC
Harvey,

I disagree with your answer. To me step and direction deals or phase
deals with the logic level signaling to the drives. What you are
explaining is the power level signals to the motors. In phase signaling
you have 4 logic level signals to the drive with each one controlling a
drive transistor or MOSFET directly. With step and direction you have 2
logic signals to the drive and the drive has some intelligents to
interpret the step and direction signals and convert them to the 4
signals needed to drive the transistors or MOSFETS.

You are correct that there are various drive methods for a stepper
motor, but that is a different thing than the signaling method to the
drive.

Tim
[Denver, CO]
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> -----Original Message-----
> >I think I understand what Step/Dir is. There is a signal for the
> >direction, and the "step" part of it is what gets pulsed to actually
> >move the stepper. Correct?
> >
> >So can someone explain what "phase" is? I get the impression it's a
> >different scheme to drive a stepper but that's my only clue.
>
> Various drive schemes...
>
> one is the 1 2 3 4 1 2 3 4 phase sequence, which is called
> "wave drive" or "full step".
>
> another is
>
> 1 12 2 23 3 34 4 41 1..... Which is called half stepping.
> See if you can find the specs on the L297 and 298 chips, and
> migrate to the app notes for these chips... Gives you a good
> idea of what the chips will do, as well as the fundamentals
> of driving steppers. They're made by ST microelectronics.
>
> Harvey

Discussion Thread

volitan712003 2003-08-24 08:57:56 UTC Phase vs. Step/Dir? Harvey White 2003-08-24 09:48:13 UTC Re: [CAD_CAM_EDM_DRO] Phase vs. Step/Dir? Robert Campbell 2003-08-24 10:00:02 UTC Re: [CAD_CAM_EDM_DRO] Phase vs. Step/Dir? Tim Goldstein 2003-08-24 11:27:00 UTC RE: [CAD_CAM_EDM_DRO] Phase vs. Step/Dir? Harvey White 2003-08-24 11:53:59 UTC Re: [CAD_CAM_EDM_DRO] Phase vs. Step/Dir? volitan712003 2003-08-24 12:24:09 UTC Re: Phase vs. Step/Dir? Tim Goldstein 2003-08-24 14:28:02 UTC RE: [CAD_CAM_EDM_DRO] Re: Phase vs. Step/Dir?