Making a DAQmx device look like an ASIO device

[epotenziani]

I have a USB-6210 DAQmx and am trying to interface it to SpectrumLab software for VLF and LF analysis. SL has a number of methods of getting audio signals into it; the easiest is that it recognizes ASIO devices (e.g. sound cards) and lets you select amongst them. Is anyone aware of a VI or other way of "wraping" up a Labview VI to make it look (to the OS) as an ASIO-compliant device?  Thanks for any help, Ernie.

[Raajit_Lall]

Hi,

The USB-6210 is only capable of acquiring data.  You can use LabVIEW in various ways, to make it look like it is recognizing the sound cards.  You would still need to feed the channels on the 6210 with analog/digital data.  There is no actual way of getting the card to recognize what is plugged into the PCI bus etc.  Could you give me a little more information on what is your application and what you are trying to achieve.  How exactly do you have signals going into your USB device.

Thank you,

[epotenziani]

Raajit

I have the USB-6210 connected to two antennas ( 100 Hz to 125 kHz) via the analog in ports. For testing, I wrote a short LabView routine that reads the signal off the analog in port of the USB-6210 and runs it through a Spectrum Analyzer VI and displays it on screen in real time. That works fine; I can see various radio signals clearly. The trick I am attempting is to stream that data out to an external program for processing, SpectrumLab (SL).  SL,at

http://www.qsl.net/dl4yhf/spectra1.html

is a program geared towards audio and LF/VLF radio processing (lots of built in routines for demod, DSP, etc). SL has several ways of getting data into it; the easiest is that it will recognize audio devices that support ASIO. That's the route I'm trying to take. The alternative is to pass the data to SL via WM_COPYDATA messages. I have taken the short NI C language example (included with the Labview distribution) for controlling the USB-6210 and gotten that running to voltage data from the USB-6210 directly to the screen (for me, a miracle in itself). But it's a long path on getting that working with WM_COPYDATA messages. The problem is, is that I am not a C programmer by any stretch of the imagination; I'm mainly a FORTRAN programmer (which gives away my age). So I am looking at a way of getting the data from the USB-6210 via the first technique. If unsuccesful, I will have to buckle down and just go via the C programming and WM_COPYDATA route.

Thanks for your help,

Ernie

[Dennis_Knutson]

The USB-6210 will not appear as a windows sound card.

1. You can create create all of the routines you need in LabVIEW and not worry about the other program.

2. You can use a sound card that is supported by the other program and not use the USB-6210.

3. You can use the USB-6210 and LabVIEW to directly communicate to the other program with the Call Library Function Node and the SendMessage function in the windows api. No need to do any programming in C. Search the forum for SendMessage.

[epotenziani]

Dennis

Choice 1 is not an option as the external program is very powerful with a LOT of routines and tools already written for the VLF and LF radio bands.  It would be like reinventing the wheel. Choice 2 -  I am already doing to a degree. I have a USB sound ADC with a 96 kilosamples per sec digitizing rate. That allows RF detection up to 48 kHz. I have another sound ADC on order with a 192 kilosample digitizing rate ; with that I can go up to 96 kHz RF.  The NI USB-6210 has the advantage of being capable of 250 kilosamples per second so I am able to cover up to 125 kHz RF signals. I'm tied to using USB so the A/D would work on almost any laptop.  I wasn't aware of choice #3; I will look into that. Thanks for your help - Ernie