I can't acces the 1MHz Clock in the timed loop

[Poly Meca]

Hi there,

I'm trying to acces the 1 MHz clock in the timed loop but I can't select it. I read the help and it says that I need to have the real-time module installed. It is installed except the RTX. Do I need it?

What do I need, finally, to acces this clock?

Thanks

[Kaustubh_vc]

Hi there,

Yes you need it?

Just go through the presentation hope so all your doubts related will be cleared..

Thanks

Kaustubh

VC (Pune)

INDIA

LV 7.1 DSC on WIN XP

[AllanS]

Hello Poly Meca!

In order to access the 1MHz clock you will need to be targeted to a real time device.  RTX gives you the ability to run a real time target under Windows XP there are other options as far as a real time OS goes.  If you have any further questions from this or the posted presentation please feel free to ask.  Have a great day!

Allan S.

National Instruments

[Poly Meca]

Hi there,

Thanks for your help.

I just found that there's a continuous clock on the hardware (ISA card) and that I can communicate with it with the .dll.
I have to use one function to start/stop the clock and one other to read both the incremental and absolute value.
The function returns the status, the absolute counter value, the "alarm", the incremental value and the amplitude status.

In the function description, it says that "The EnDat counter value has the same significance as the incremental value i.e., 1.0 represents one signal period."

The thing is that I can't figure out how to use this function in Labview (with the timed-loop or something else).

Does somedy have an example or an idea?

Thank you!

[Brett_B.]

Hello Poly Meca,

How to use the function should be included in the dll/HW instructions that came with your card.  There is a good tutorial online that should provide you with more information on using a dll should you need it.

Using External Code with LabVIEW

regards,
Brett Burger

[Poly Meca]

Hi,

Thanks for your answer.

I know how to use the call library function node. The thing is that I don't know how to use what my function returns with the functions of labview.

I don't know how Labview's functions (while loop, timed loop, etc) can interact with the data that my function called by the Call Library function Node returns. In fact, the function in the .dll returns kinds of variable like double, integers, nothing that can help me with Labview's functions.

How is it possible to acquire data with a loop, while I need to acces a clock in a card with a .dll finction that returns "double" variables?

Thanks again!

[Brett_B.]

What data are you acquiring?...with what hardware?  Are you still talking about accessing your clock count from your ISA board?

The loop in LabVIEW is a execution structure.  Any icon you place in the loop will execute as if it were in a "do until" statement in text based programming.If you place the call library function in the loop you will be calling that dll once per iteration until the condition is met that stops the loop.

Multiple threads can be executed in the same loop...or...for more advanced applications in separate loops.  Your dll call and your daq thread can reside in the same loop.

If you need more help please answer my above questions and let me know what your specific question is...or where you are having problems.

-Brett