HELP! Two different AO's, one DAQ assistant? It's the newb again... VI attached.

[Ralph@NES]

Hello again guys, I much appreciate all the help I've gotten here already.

I've been setting up to take thermocouple readings from 8 sources and trigger one analog output when a limit was reached.  Got that working with some external relays and wiring.

Now the scope has changed--I now have 16 channels of thermocouple (AI; two banks of 8 couples) and I need to control two channels of AO to activate depending on which bank of 8 has the over limit.  This has to be discreet to each bank of 8--if an overlimit value comes from 1-8 it must turn on AO0.  If the overlimit comes from 9-16 it must turn on AO1.

I've attached the VI I've been working on, which now isn't working.  I simply tried to mirror my setup for the 1st 8 channels and now am getting an error 50103 stating that a resource was reserved.  I have my input DAQ assistants set to different AI channels and my output assistants set to different AO channels.  I'm confused as to where the resources are conflicting.

Help?  Please?

[Dennis_Knutson]

http://forums.ni.com/ni/board/message?board.id=250&message.id=21693

[Ralph@NES]

OK, since that seems to be not really the way to go, is there a way to 'split' the data by channels out of my DAQ asst 1 so that I can send 1-8 to AO0 and 9-16 to AO1?

I ditched the second input assistant and added the other 8 channels of AI to my first one.  Added a 'select signals' to the output and now can control whether signals 1-8 pass through or not, but it doesn't seem to recognize the ones past 8?  I could use two of these and route my outputs if it was recognizing the other 8.

[Dennis_Knutson]

I never use the express VIs and the signal data type but if I did, I would use the Select Signals functions to get to two separate groups, do the comparison, set a value based on the comparison, and then merger the two different signals before the DAQ Express that does the analog output. Something like the attachment. In this attachment, you would get an output on both analog outputs if the error condition is met with both. One thing about Select signals is that you first have to run the DAQ Assistant connected to it before you get a correct list of signals to separate.

Message Edited by Dennis Knutson on 05-19-2006 09:42 AM

[Ralph@NES]

Ah I see...  I didn't know you had to run it to get the correct list.  Thanks.

What I ended up doing in the meantime was use a 'split signals' with 16 branches and then a pair of 'merge signals' with 8 ins each.  Routed them to two different displays, output VI's, and led's.

I've got this within a breath of doing what I need it to for the time being.  The only thing I'm missing is the write data on the 2nd batch of inputs when the overtemp condition is true.

[Ralph@NES]

Which was solved with an 'or' going into my other 'or'.

My lord this thing is ugly but seems to be doing what it's supposed to.  I've gotta get a better handle on how to do this stuff right!