CI Semi Period Digital Filter

Hello!
I'm having difficulty configuring my counter inputs. Pretty new to Counter/Timer setups as well.
LabVIEW 8.5 and MAX 4.5.
The signals I am sampling are 200 Hz, PWM ranging from 5% to 95%, cycling back and forth.
I'm using 7 counters in a PCI-6602. The code I'm including is an example from my setup.
We are requiring the use of the Rising Digital Edge, and I'd like to include CI.PulseWidth.DigFltr.Enable to enable debouncing.
All inputs are connected to the Gate terminals on each counter.
Is my programming for the Risin edge correct? I am seeing the falling edge come through first on several occasions.
And for the debouncing programming, I always get error -200452. None of my searches revealed anything applicable.
I have also tried setting my Min value on the Semi Period configure to 0.0002 instead of 1e-7 with same results.
This is a hot project, so thank you for your time in advance!
Attachments:
Counter PWM Setup 0.vi ‏17 KB

Hi Oley,
It looks like there's two questions here:
1. Programming for the Rising Edge:
I'm assuming that you want to start the task on the rising edge of your input signal. It looks like you have set the 6602 to arm off of the rising edge of your 20 MHz timebase (which is independent of the input signal). Rather than setting the Arm Start Trigger, you can use a DAQmx Channel Property Node to set the starting edge (see below).
2. Error -200452 (Specified property is not supported by the device or is not applicable to the task.)
The property node that you have configured to enable the filter needs to be specific to the type of task that you are running (in your case, CI.SemiPeriod). You have selected CI.PulseWidth which is a different task type. The filtering is usable with a SemiPeriod task by simply changing the property node accordingly.
The property node that you configure should look like this:
This will both enable the filtering and tell the device to begin measuring on the first rising edge. Make sure that all the properties begin with CI.SemiPeriod--it can be easy to overlook at times since many of the different task types have identical properties available.
I hope this helps out, let me know if you have any questions or run into any issues implementing the above.
Best Regards,
John Passiak

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Up to 6 counters on this card are sampling the same signal in our testing configuration.
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In addition these calls are made:
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Hi Manfred7,
did you already test this behaviour with a simple example from us?
Just go through the example database and try the examples there.
These examples should work.
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I am trying to use a digital filter on my PXI-6602 card and I can't get it to configure for an external clock. It keeps telling me the numbers don't match up but I don't see the logic to the numbers it supports. Here is the error I got for a time base of 100 Hz and a min pulse width of 1/(100 / 2) based on the period of 2 clock cycles.
Desired Minimum Pulse Width could not be produced.
Minimum Pulse Width is affected by the Digital Filter Timebase Source and the Digital Filter Timebase Rate. To see how these two property settings can affect the Minimum Pulse Width, refer to product documentation for more details.
Property: CI.CountEdges.DigFltr.TimebaseSrc
Requested Value: /PXI1Slot2/PFI36
Property: CI.CountEdges.DigFltr.TimebaseRate
Requested Value: 100.000000
Property: CI.CountEdges.DigFltr.MinPulseWidth
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Task Name: _unnamedTask<49>
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Attached is a copy of my VI
Attachments:
External Clock for Filter.jpg ‏131 KB

Digital filtering ensures that a high pulse is high for at least a certain time (minimum pulse width) in microseconds. This is to ensure that a fluke noise signal does not count as a high pulse. It also ensures that a voltage overshoot to the high value does not register more than one high pulse as it settles in to the value.
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5 µs
1 µs
500 ns
100 ns
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Message Edited by PjayD on 04-14-2010 09:38 AM
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Signal_Capteur_modified.bmp ‏38 KB

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Solved!
Go to Solution.
Attachments:
Multi PWM Reading.vi ‏118 KB
erorr message.doc ‏91 KB

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Multi PWM Reading.vi ‏51 KB

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