Controlling usb x series 6353 with ANSI C?

[seaweedchips]

Hey folks, I'm wondering how to control this usb device using ANSI C. I want to be able to generate a voltage between 0-10 volts from the analog output which goes into the analog input to be read using ANSI C.

[Frisbee]

The DAQmx driver interfaces with NI's DAQ hardware and provides support for LabVIEW, .NET, and C. You can download the DAQmx driver, which includes the C API, at the following location:
http://joule.ni.com/nidu/cds/view/p/id/4240/lang/en

I recommend looking through the following documents to understand how to use the driver:

Using NI-DAQmx in Text Based Programming Environments
http://www.ni.com/white-paper/5409/en/

Getting Started with NI-DAQmx: Main Page
http://www.ni.com/white-paper/5434/en/

Also, NI offers an integrated C development environment, LabWindows/CVI. More information about this IDE can be found through the link below:
http://www.ni.com/lwcvi/

[seaweedchips]

So how do I exactly use a C program to communicate with my NI device? Do I use LabWindows or are there other options?

[Dennis_Knutson]

From your initial question, it sounded like you already had C experience.

LabWindows/CVI is a C IDE that takes out some of pain of doing text programming but it certainly is not the only option. There's a rumor that a company called microsoft has a C compiler that is kind of popular.

[seaweedchips]

Yes, I have some basic experience in C. So if I want to communicate with my USB device, I should use LabWindows?

[Dennis_Knutson]

Or Gnu, Borland, Microsoft, etc. You can also consider LabVIEW and you don't need to mess around with any text.

[seaweedchips]

So I am trying to control it, but I have no clue on how to use LabWindows do control my USB device.

What I want to do is generate a voltage from the AO which is connected to an AI through a wire, this way both the analog output/input ports have the same voltage.

How do I exactly do tihs? Do I create a task and then create a AO voltage channel and also create a AI voltage channel, or do I just need to create a AO voltage channel since the AI and Ao are wired together?

[Dennis_Knutson]

You have to create both an analog in and analog out task.

Have you looked at the examples that come with LabWindows/CVI?

[seaweedchips]

Yes I have.

So I would need to create 2 tasks. One DAQmxCreateTask function for the AO and another for the AI?

And then from there create voltage channels for both AI and AO? How can I exactly control the amount of voltage I want going through the ports? On the examples there's a variable called DAQmx_Val_Volts, where does this come from?

[Dennis_Knutson]

I don't have CVI right now and you don't specify which one. Does the project have a uir file where you set the value from a gui?