Re : Re: Re : Re: Get PXI digitizer information

[mmakster]

Hello,

How can I get information with LabView about the PXI digitizer I am using, like its name (e.g. PXI5122), gain and number of bits or V/LSB ?

I see that some of this info is available in VI "niScope Fetch Binary 16", but I would like to get the info before fetching any waveforms (to write a setup file).  Also, that particular VI doesn't seem to provide the digitizer name.  I can find the resource name, but that returns a slot, which is not exactly what I want, since we may move the digitizer around.

I am using LabView 8.0 on Windows XP.

Philippe 

[Steve__M.]

Hello Philippe,

Some similar problem was treated here. Also you can refer to Programmatically Determining What DAQ Devices Are In My System and Programmatically Obtaining the Product Name of an NI-DAQmx Device in LabVIEW

Moreover, if you speak French I invite you to post in the corresponding French forum in order to solve your problem efficiently.

I hope it helps.

Regards,

Message Edité par Steve Mohamed le 11-03-2008 04:56 AM

Message Edité par Steve Mohamed le 11-03-2008 04:56 AM

Message Edité par Steve Mohamed le 11-03-2008 04:58 AM

[mmakster]

Dear Steve,

Thanks for your answer, but the problem remains.  For instance, I tried the VI "device_info.vi" you linked to. It only finds one of the three digitizers in the PXI chassis (the 6070E, but not the 5122 and 5152; chassis is a PXI-1002).  Is there some VI to which I can pass an instrument handle for instance, and get the digitizer's name ?  Even better would be for the user to input the digitizer name, and then the program finds what slot it is in and creates the instrument handle etc...

Not sure I understand your point about language.

Philippe 

[Steve__M. · Accepted solution]

Hi,

You should use the NI-ModInst VI to query the system for information about installed Ni modular instruments devices.

I made an example that shows how to use these VIs

Regards,

Message Edité par Steve Mohamed le 11-05-2008 05:16 AM

[mmakster]

Could you resend your VI under LabView 8.0 ?

Thanks,

Philippe 

[mmakster]

I found a way to determine what slot a given digitizer is in (see attached).   Now I need a way to find the true vertical scale the digitizer uses (for instance, if I select +- 5 V, the actual result is somewhat smaller), or the Volts per ADU, before triggering on any events.  Any ideas out there ?

Philippe 

[Steve__M.]

Hello Philippe,

If I understand, does it mean the LSB (Least Significant Bit) ? One LSB is the voltage change increment corresponding to an LSB change in the digital value : 

1 LSB = Input Range of ADC / Gain

                        2^{number  of ADC bits}

For example, the AT-MIO-16X can settle to +- 0.5 LSB (or +- 76.3 µV) using a gain of 1 and an input range of 10 V.

+- 0.5 LSB =  ( 10/1 ) *0.5 =     5        = +- 76.3 µV

                          2¹⁶                 65,536

Otherwise if your first problem is solved, please mark this thread as solved and post a new thread with your question.

Regards,

Message Edité par Steve Mohamed le 11-06-2008 05:15 AM