Synchronize Counter and Analog Input on cDAQ-9174

[A-T-R]

Hi all,

I have to continually measure a PWM signal with levels higher than TTL. For this, I'd like to use the NI-9411 module on a NI-9174 cDAQ chassis. In addition, I also have to measure another signal (scaled position measurement, 0-10V) on an analog input module (NI-9221). Both measurements have to be synchronized! Then a X-Y graph (X = Position, Y = Pulse width) has to be build.

How can I achieve this? Will the measurement automatically be synchronized, because in "implicit" mode counters use the internal timebase of the chassis and the analog input task does the same ("onboard clock"). Or do I have to explicitly tell both tasks that they each should use the "cDAQx/20MHzTimebase"?

Or do I have to generate my own clock signal with another counter and use this as the clock for the two other tasks (PWM measurement + Analog input). I ask this because the 9411 module specification says that it can be used only with a "Max clock rate = 2 MHz", and this rate isn't directly available from the chassis!

How can I make sure that (in both cases) the tasks start simultaneously? Can I share a trigger with the two tasks?

Now assuming that all that works (somehow): Which value of the many analog values would I use for a building the xy graph and to set in relation to a certain pulse width value?

Any help is appreciated!

Thanks in advance

A:T:R

[A-T-R]

Anyone out there?

Regards

A:T:R

[CarstenS]

Hi A:T:R,

please take a look at this example, it shows how to synchronize a counter measurement with an analog measurement.

Kind regards

Carsten

[A-T-R]

Ah...sorry for the private message Carsten...I didn't see the link!

Well, I try...but I'm not sure if it will work with the USB devices...Besides that, I still have no information which timebase to use for the NI-9411 module...

Thanks so far...perhaps somebody has some detailed information?

Regards

A:T:R

[A-T-R]

Darn...double-clicked...