Changing the pulse width of a counter on-the-fly - ?

I'm seeing strange behavior when trying to change the pulse width of a
counter while it is running continuously.  Using the property node
I can set the DAQmx Channel Properties "Low
Time" and "High Time" when the values are
changed by the user (see attached VI).  The first change is
ignored initially, but then applied when a second change is made, i.e.
the changes are applied one step late.  If I read the respective
properties the values are what is set but not what is being
generated and seen on an o-scope.  I added a
condition of watching the property "Ready For New Value" before applying the
change, but that doesn't alter the behavior.  What am I missing?



Windows XP

LabVIEW 7.1

DAQmx 7.4.0f0

PCI-6251



Thanks,



DTL


GenDigPulseTrain-ChangingSpecs II.vi:
http://forums.ni.com/attachments/ni/170/134116/1/GenDigPulseTrain-ChangingSpecs II.vi
.

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