Problem reading PXI 5122 with command AIReadAcquisition

[shawnyap]

Hi everyone,

I encountered this problem : "The specified device is not a National Instruments product, the driver does not support the device(for example, the driver was released before the device was supported), or the device has not been configured using the Measurement & Automation Explorer"

Please help.

Thanks

[Tica]

Hello,

This problem usually occurs if you are using the wrong name to refer to your device or if you don't have the device configured properly in MAX. To check what the correct device name is, go to MAX and expand Devices and Interfaces. Under DAQmx Devices you should have the PXI-5122 listed with a name in quotes similar to "PXI1Slot3" or "Dev1". This is the name you have to use when you call the AIReadAcquisition function.

Another thing you can do to check that the device is recognized properly is from MAX, under Devices and Interfaces right-click the PXI-5122 and do a self-test on the board. If the test doesn't pass, reset the device and try it again. If this doesn't fix the problem let me know what error you get and if the chassis is recognized properly. What chassis are you using? Are you using a controller or a MXI connection?

Hope this helps,

Tica T

[shawnyap]

thanks for your help. it works.

However, i encountered another problem using example codes (ConfiguredAcquisition) in Niscope.

It has many trigger functions but whenever i use Edge trigger with 3 V trigger level,it hangs.

No error message and data are displayed. 

I'm still using the PXI 5122 for the acquisition.

FYI,my sensor gives an output of 2.5V in Immediate mode, therefore a 3V trigger is feasible.

Please help. 

Thanks

[Tica]

Hi,

If you specify your Edge trigger with a trigger level of 3 V then the device won’t trigger until it receives a signal that is at least 3 V. You mentioned that your sensor output is 2.5 V which will never trigger the digitizer for the trigger level you are using.

Does your sensor output a constant 2.5 V DC signal? If it does then the trigger won’t occur either. An edge trigger occurs when the trigger signal crosses the trigger level specified with the set trigger slope.  If your trigger is a constant 2.5 V signal then you won’t get the 5122 to trigger. If it is more of a square wave though it would be perfect as long as you set the trigger level to 2.5 V.

Hope this clarifies things a little better.

Good luck,

Tica

[shawnyap]

Hi Tica,

My sensor gives a constant 2.5V output. I have tried using 1V trigger today and it give this error : Error BFFA2003 occurred at niScopeFetch.

Possible Reasons: Max time exceeded before the operation completed.

The timeout is 20s, is this long enough?

Thanks

[mvr]

Your sensor outputs a constant signal around 2.5V.  The digitizer will not trigger because the signal edge does not cross your setpoint, (the 3V or 1V threshold).  You may want to look at this

http://zone.ni.com/devzone/conceptd.nsf/webmain/AE35C60EED0C7CAA86256F3B000A2CF4

You either want an immediate trigger for continuous acquisition or a software trigger if you want to acquire data at an interval set by your software.  You could possible get what you want with a window trigger if you just want to acquire data in the range around 2.5V.  Edge will not work for you in this case because your signal does not have an edge that passes through the threshold you specify.

Good Luck

[shawnyap]

Hi mvr,

Thanks for the link,I understand the triggering functions better. I suppose that I need to configure a software triggering to capture my continuous signal(please see attached)? If that's the case, is it possible for you to send me a sample on that?

Thanks!

shawn

[mvr]

Assuming you have one of the CVI versions from the last few years try this:

Under the Help menu select Find Examples, this should open the NI Example finder window

Expand the entries for Hardware Input and Output ==> DAQmx ==>Analog measurements ==> Voltage

The two that should interest you right away are Acq-IntClk.prj for acquiring a single block of data and ContAcq-IntClk.prj for continuous samples.  Take a look and see if they are what you need.  You may also want to look at some of the other examples to see if they give you ideas on which way to go.

Good Luck

[shawnyap]

Hi mvr,

I succeedded in using the software triggering function in the example code, Configured Acquisition. Thanks!

[mvr]

That's great that they had the enough information for you to get it going.  Good Luck.