Dynamic data aquisition on USB-6212

[sbk143]

I am using USB-6212 to aquire (AI) and control (DO) from/to 8 UUTs. It works perfectly. What I want to do is dynamically launch my daq vi for each UUT that will acquire AI and DO data for its respective lines.

For example, I launch UUT-1 daq vi to get AI data from ai0 and DO data to p0.0, p0.1 and p0.2. Then launch UUT-2 to get data from ai1 and data DO to p0.3, p0.4 and p0.5 at different times.

I want to be able to launch and stop daq at my will.

Here is the problem. So, I tried launching VIs dynamically, which works ok. But, data aquisition is not working. It works for the first launch of the daq vi. For the other UUTs, it give me this error:

Error -50103 occurred at DAQmx Start Task.vi:2

Possible reason(s):

NI Platform Services:  The specified resource is reserved. The operation could not be completed as specified.

Task Name: _unnamedTask<15>

So, my question is, can this be done? Would USB-6212 support dynamically allocating task resources on DAQmx?

I have attached my main launch vi and daq vi block diagrams. Any help/feedback is appreciated.

[John_P1]

Hi sbk143,

The 6212 only has a single analog input timing engine, so you cannot run more than a single analog input task at a time.

What you can do is acquire from all of your AI channels in a single task, then programmatically index out the channels that you are interested in.

Your approach would work for software-timed DO, so you can control the UUTs independently at different times.

Best Regards,