Synchronize sampling of rpm using frequency counter with force (voltage) signals

I have a VI attached which converts the voltage values measured from the ATI force/torque senosr to force values. I would like to integrate the measuring of TTL pulses from an RPM senosr. There is a bug with my current program, as the RPM value only updates once. If I put the read VI in a while loop, the program returns an error. How should I modify my code to solve this, and as well as to synchronize the recording of data from both sensors?
I have no prior labview experience, and really appreciate any help.
Attachments:
atidaqft-mx.llb ‏93 KB

Dear Jochen,
(1) Principally, I'd like to use PCI-6602 to be a motion encoder also be a counter (Is it possible? Due to the manual, it is possible). I expect to have all information, such as position, time, velocity, etc. from that motion encoder (or at least the position and time). It is also expected of using PCI-6602 to do all measurements that I mentioned before . My meaning is, after having a signal from the counter, that 'count' will be converted to desire units under other programs. So, in this case, PCI-6602 is only used to get the 'count'.
Simplified, the voltage command will send to the system (linear motor) through PCI-6052E (-10V to 10V). The actual position or other actual information will be catched (read) by using PCI-6602 (as a motion encoder, also as a counter). Then, this actual position will be used as a feedback, that will be compared to desired position.
Is that also possible to use PCI-6602 be a motion controller + a counter + a frequency measurement in a same time parallely?
I don't decide yet (I don't know) which acquisition rate will be needed/required, higher is better.
(2) I'd like to apply an adaptive robust controller (yes, it is a closed loop system) under matlab with their feature called Real-Time-Workshop instead of using LV.
(3) Power drive for the linear system will be driven by AC servo drive.
Thanks for your help before,
Warmly regards,
hendro

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Hello Waw,
Take a look at this KnowledgeBase to see if it fixes the problem.
http://digital.ni.com/public.nsf/websearch/862567530005F09E8625681C0074935E?OpenDocument
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Ben,
I having read previous email which I send earlier with general overview, we discussed in more detail within our team and I am giviing the specific answers.
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Solved!
Go to Solution.

Hi Vic,
This is actually expected on an M Series device. Here's a timing diagram from the M Series User Manual that might make this a bit more clear:
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Best Regards,
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Buttons.vi ‏77 KB

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Hello all,
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Go to Solution.
Attachments:
SimpleDAQ.vi ‏44 KB
LV_Error.JPG ‏31 KB

Maybe third times the charm?
So I've finally got a good handle on why the VI is having problems at low RPM though I'm somewhat embarassed how long it took me to do that
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Attachments:
SimpleDAQ_1_Start Stop.vi ‏48 KB

How can I implement a Digital I/O counter with a maximum source frequency of 80 MHz (like 6602 board) using CompactRIO?

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I am working on getting just the counter working by using
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Attachments:
Counter_error.jpg ‏45 KB

Using a Counter to error-check External Sample Clock

Hi all,
I am newish to labview and am working on a data acquisition project. I've managed to get the basics under control, but here's my situation and question...
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Message Edited by mumech on 07-22-2008 01:05 AM
Attachments:
REncoder Specs.pdf ‏312 KB

Thanks very much for your reply. I had come across the use of counters with angular encoders but hadn't quite thought of the concept in this way.
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Frequency counter unreliable using rotary vane anemometer

I have set up an anemometer to measure air flow speed, with the signal being acquired by a 9402 module in a cDAQ-9174 chassis (4 slot). I am using Signal Express 2011 to program the instrument.
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Attachments:
EXPT 20 - ANEMOMETER NOISE.pdf ‏49 KB
EXPT 20 Anemometer Noise.seproj ‏637 KB

I have logged the voltage signal coming from the anemometer, using our 9239, a report of a few cycles is attached as a PDF. The graph clearly shows a small digital bounce. The noise is small compared to the signal, is there any way it can be filtered when acquired by the 9402?
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Attachments:
EXPT 20 Anemometer Noise Voltage.seproj ‏261 KB
EXPT 20 Anemometer Noise Voltage.pdf ‏19 KB

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hi, thanks for the answer, but unfortunatly it´s not what i ment.
i need to configure a counter on the pci6602 wich divides down the frequency "f_in" of the square pulses connected to it´s "source" pin by "divisor" and puts out square pulses with frequency f_out=f_in/divisor at another pin. That process should take place only on the 6602-board without using the cpu.
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servus
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Attachments:
Divider_Config_mw.vi ‏40 KB

Synchronize sampling of rpm using frequency counter with force (voltage) signals

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