API or VISA?

[orchid]

Hello,

I am using Labview 7.1 with vista. I am gonna record the EEG signal using TT-USB (Flexcomp Infiniti encoder) and want to display it on the Labview. I have already ask the question on the Multifunction DAQ in case I would like to try NI-VISA to read the input from the USB. Unfortunately, the forumer said that I have to use API that suggested by the vendor but I really don't know how to do it. Can anyone help me the step to do? Is there any example or documentation I can refer?

What documentation of API I should provide to you?

Thanks

[MikeS81]

Hi orchid,

i think there is no question to use API or VISA, you got the answer here. If you have dll files you can use the "Call Libraray function node". You need a description of the exported functions and then you can build your vi´s.

Hope it helps. Mike

[orchid]

But I do not know how to start. Do you have any example about this?

[MikeS81]

Hi orchid,

try this KB to start http://digital.ni.com/public.nsf/allkb/DCB90714981A1F148625731E00797C33

Mike

[orchid]

I am bit confius. It is means that I still have to use VISA and API or what. What type of output will appear? Can it be in graph because I want to record EEG signal using Labview. So, I hope to see the output signal from the Labview.  Any idea?

[Dennis_Knutson]

The vendor has provided you with some information on their dll's I'm assuming. This is their api and you use the Call Library Function Node to access it. Whatever kind of output you get from the dll should be documented somewhere. You have not provided a link to or the documentation itself so all anyone can do is speculate. You need to go through the api documentation and find the function that returns data from the sensors. Once you have that, it should be possible to plot it.

To get some specific help, you would need to attach the .h file, the .dll, and the api documentation.

[orchid]

Hi,

I got some problem. I am using vista. So, when I try to built myshared.dll on microsoft visual C++ 6.0, it is not compatible with vista. Now, I am trying to use visual 2005 which is compatible with vista. Also, I has upgrade my labview to 8.5. Do anyone have a example on how to call library function node using those two above?

Appreciate your help.

Thanks 

[jpaul]

Hi Orchid,

I have a few follow up questions so that I'm able to taylor my response to your specific situation:

1- Can you tell me a bit more about your problem? Are you seeing an error when you try to configure your Call Library Function Node?

2- Are you compiling your DLL for a 32-bit or 64-bit target in Visual Studio 2005?

3- Are you running as an adminisrator on your Vista machine? To find out more information on this issue (how to ensure that you are), see the following knowledge base: Unexpected Behavior When Calling External Code with LabVIEW in Vista

Thanks!

Cheers,

Jonah
Applications Engineer

National Instruments

[orchid]

I want to capture raw EEG data on the labview platform. The sampled data is encoded using Flexcomp encoder (10 channel) and transmitted to the software via optical fiber, connected to the TT-USB interface unit, which converts the light into USB serial data. I am using TT-USB to interface with labview 8.5.  Actually, I want to use NI-VISA, but the company was suggested to use DLLs (API) to manage the data capture and processing. Because of the uncompatiblity of visual C++ 6.0 with vista, now I am going to use Microsoft Visual Studio 2005.

Actually, I do not have any idea how to start.Can you give me an idea of it?

3. I a

[orchid]

I want to capture raw EEG data on the labview platform. The sampled data is encoded using Flexcomp encoder (10 channel) and transmitted to the software via optical fiber, connected to the TT-USB interface unit, which converts the light into USB serial data. I am using TT-USB to interface with labview 8.5.  Actually, I want to use NI-VISA, but the company was suggested to use DLLs (API) to manage the data capture and processing. Because of the uncompatiblity of visual C++ 6.0 with vista, now I am going to use Microsoft Visual Studio 2005.

Actually, I do not have any idea how to start.Can you give me an idea of it?

3. I am