But have a look at ADlink or usbdux (http://www.linux-usb-daq.co.uk/)
Regards
-didi
--
You received this message because you are subscribed to the Google Groups "Comedi: Linux Control and Measurement Device Interface" group.
To post to this group, send email to comed...@googlegroups.com.
To unsubscribe from this group, send email to comedi_list...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/comedi_list?hl=en.
I could not figure out how to do this. My solution was to have
two DAC cards and run the analog output and input on simultaneously
executing threads. NI cards do have the capability of outputting
a continuous AO waveform from and on board buffer. Unfortunately
the comedi interface is not done. This would be a *good thing* to
implement if someone cared enough and knew how. That person is not
me however :-(
Don Taber
That's close to what I do on our NI PCI 6052E. For any NI-STC-based
card, you can set up the AO timing so it triggers off of the AI start
signal. With the same clock frequency, the two should be fairly well
synchronized. I wrote up a blog post summarizing the change that
introduced this capability to Comedi, which you might find informative
[1]. I don't have any examples for you in C/C++, but I have examples
[2] in my pycomedi [3] Python wrapper, which should run pretty close
to the C equivalent. If you need help translating the example to C,
let me know.
All of the above is about synchronized I/O. If you want real time
control (i.e. you're changing your output signal based on the inputs),
that's a whole other can of worms, of which I know very little. The
basic approach will be the same, but you'll need to ensure that the
output channel(s) don't run out of data in their output buffer.
Cheers,
Trevor
[1]: http://blog.tremily.us/posts/Comedi_and_NI_triggering/
[2]: http://git.tremily.us/?p=pycomedi.git;a=blob;f=doc/synchronized_analog_IO.txt;hb=HEAD
[3]: http://blog.tremily.us/posts/pycomedi/
--
This email may be signed or encrypted with GnuPG (http://www.gnupg.org).
For more information, see http://en.wikipedia.org/wiki/Pretty_Good_Privacy