Author Topic: pmdx 422 step pulse width  (Read 4115 times)

jcrowe

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pmdx 422 step pulse width
« on: April 10, 2015, 04:39:56 PM »
We are having an issue with step pulse width.  We get a 5 uSec pulse width to the motors no matter if we set the smartbob config to 5uS or 10uS.  I would like at least a 10us pulse. The old controller we are replacing put out a much wider pulse and drives the Bridgeport MagAmp drivers well.  This narrow pulse may work (I will find out Monday when we finally connect it to the mill), but I just know that it isn't even close to the output of the original controller.  I'm not sure of the original pulse width, but it was about 50% duty cycle (on 50% and off 50%).  What is going on?  It does change the setting in the Machine.ini file, but seems to have zero effect on output pulses?  Is there a way to set it higher than 10uSeconds?

Mach4 Hobby 4.0.1.2270 Build 2270
PMDX-422 Rev B1 (Ser# 32785)
Bridgeport Series One CNC Mill (Soon)

Bob at PMDX

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Re: pmdx 422 step pulse width
« Reply #1 on: April 10, 2015, 05:45:57 PM »
I have verified that there is an issue with setting the step signal pulse width with the latest plug-in releases (0.19.100 through 0.23.107).  It may also be present in earlier releases, I haven't tested them yet.  5us pulse widths always work.  10us pulse widths sometimes do and sometimes don't.  Stay tuned for a plug-in update.
« Last Edit: April 10, 2015, 09:30:43 PM by Bob at PMDX »
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