Which is the best way to edit this program and make it read 1 sample from each channel?

[Chefbo]

The original program was made with Traditional NI-DAQ. I have edit it to DAQmx the best that i could. The program it's already applying the voltages that are generate in the code(Daqmx Write.vi). But i'm having problems with acquiring voltages it's giving me rare readings(Daqmx Read.vi)  i don't know if i have to make a (Daqmx Start Task.vi) for each channel in the program or if i can make it work with a single one. Notice i have not make many significant changes because this program is already running in another lab and they give to us the program so we didn't have so much problems but instead of getting the BNC-2090 they got the BNC-2090A that uses DAQmx instead of Traditional. So anyone can help?

[RavensFan · Accepted solution]

A BNC-2090 is just a connector block.  It has no effect on whether you need to use DAQmx or traditional DAQ.  That is determined by the DAQ card you are connecting the terminal block too.

You might be referring to this document Differences Between the BNC-2090 and BNC-2090A Connector Blocks, but that is just saying to the change in the labels of the terminal block to accurately reflect the newer DAQ cards.

What problems are you having with the new VI you just posted?  Are you getting an erro rmessage?  I don't know what "rare readings" mean.

You really shoud look at some DAQmx examples in the example finder.  Some problems you are having is that your DAQ blocks are all sort of disconnected.  Generally, you should be connecting the purple wire from your create task function, throught the start, read or write, and on to the close task.  Many of your DAQ functions are just sitting out there on little islands right now.  You should also be connecting up your error wires.

With DAQmx, you should be combining all of your analog channels in a single task.  It should look something like Dev0/AI0..AI7.  Then use an N channel 1 sample DAQmx read to get an array of the readings, which you can then use index array to break apart.

Other things you should do is replace the stacked sequence structures with flat sequence structures.  Turn on AutoGrow for some of your structures such as the loops.  In the end, you might find you can eliminate some sequence structures.

[Chefbo]

With the Traditional drivers the program didn't work it was giving me errors about the drivers that they were not supported. After changing it to Daqmx drivers it didn't give me  those errors anymore but when Daqmx Read.vi is executed sometimes it gives me the readings and sometimes it gives me 0. I pass a error in and error out through the Daqmx Read.vi that has the AI3 has a Task(Read Voltage). Everytime the reading display 0 in Rs it gives me this error code -50103.

[RavensFan]

Error -50103 says:  The specified resource is reserved. The operation could not be completed as specified.

That is the error you get when you try to access different channels in different DAQmx tasks at the same time.

As I said, you need to combine all your channels into a single DAQmx task, and to a single DAQmx read of N channels 1 sample.