refnum for ni cDAQ

[Vills]

Hello,

I was using FieldPoint and have now changed to NI cDAQ9172. We were using "FP refnum" variables to input data to FieldPoint  VIs (e.g. polymorphic FP Read.vi or FP Write.vi). Now I need to modify this LabVIEW code for NI cDAQ9172 IO modules like NI9474, NI9263, NI9203, NI9201 etc.

I tried to get information about FP refnums on web/books, but could not find any success. I am relatively a novice in LabVIEW programming. Can anyone point to the right direction where I can get information about programming a cDAQ9172 for using analog/digital input/output modules?

Can anyone please refer to the attached picture and help me in understanding how can I modify this code to use a NI cDAQ9172?

Also, how these AO or DO FP refnums are created in FP and how they can be used? What is the data type of a FP refnum?

[Seth_B.]

Hello Vills,

The Compact DAQ (cDAQ 9172) and it's modules are programmed a lot differently than the FieldPoint.  cDAQ doesn't use refnums or any of the same functions to return data, instead it uses the NI-DAQmx Driver.  As a result, there isn't really going to be a direct one-to-one replacement for the FieldPoint functions.

I would recommend you look through some of the resources on the Getting Started with NI-DAQmx page.  It includes a lot of basic tutorials on using DAQmx to communicate with DAQ devices.  I'd also recommend looking through the DAQmx examples in the LabVIEW example finder (Hardware Input and Output » DAQmx) to see what the DAQmx driver looks like in action.

Hopefully, with these resources your upgrade will go a bit smoother.

Regards,