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USB-TC01, DAQmx and Matlab Issues

I have a machine that because of an instrument attached to it, has to run an old version of NI-DAQmx (7.4). In the past I was able to use the loadlibrary function in Matlab to access the DAQmx driver (using nicaiu.dll and NIDAQmx.h), as long as I had NI-DAQ installed on the computer. Without Ni-DAQ installed on the machine, upon loading the library, I would receive the error "The specified module could not be found" in Matlab. I attributed this error to not having some other DLL that nicaiu.dll calls.


So the first of many questions:


1) What are all the files needed to call the nicaiu.dll library, such that NI-DAQ would not have to be installed on a machine?


I have recently purchased a USB-TC01. Evidently, you need NI-DAQ 9.1 or higher to develop the device (which will also evidently only run on Labview 8.2 or higher). I would like to use the thermocouple on the old machine I have. I have tried copying the 9.2 versions of nicaiu.dll and NIDAQmx.h files to the old machine, but I get the error, "The specified procedure could not be found" when I try to load the library in Matlab. Once again, it seems like the correct dll's are not being called, probably because of the difference between NI-DAQ 7.4 and 9.2.


2) Is it possible to bring over all the necessary dll's from 9.2 so that I access the library from Matlab, without having to install 9.2?


3) Can you have two versions of DAQmx on the same machine (7.4 and 9.2) without messing up the programs that call the 7.4 version of NI-DAQ? I can confirm that having Labview 8.5 and NI-DAQ 9.2 allows me to access nicaiu.dll and interrogate the USB-TCO1. Unfortunately, this is not the computer with the instrument. This would somewhat be a moot point if the temperature logger program would update at a faster rate and append the log file instead of waiting until the end of the acquisition to write the file. Then I could just have Matlab read the last value in the file. But since I can't, I need to find a way on an old machine to get the temperature data.


Any thoughts or suggestions? All computers are windows xp running sp2.

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This is the minimum install for DAQmx.


No, you cannot have multiple versions of DAQmx installed.


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Can your older DAQ device run on both DAQmx 7.4 and Traditional DAQ (legacy)? If so, you may be able to load DAQmx 9.2 (or at least the DAQmx 9.2 run-time engine) to use the DLLs with your TC01 and then still use T-DAQ to control your older DAQ device. I do not think it is possible to just copy and paste the DLLs.


It is also not possible to use two different versions of DAQmx together on one machine.



Ryan F

National Instruments
Applications Engineer
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Unfortunately, the instrument does use Daqmx.  It seems that the only solution I have is to use 2 computers, one to control the old instrument, and another to control the TC01's.  Then I can use TCP/IP to connect to the first computer and grab my data from there.  Not pretty, but it might just be the only way.  Thanks for your help!

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