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Acquiring streaming data from two sources

I�m trying to acquire data from two devices at the same time. I have written two sub VI�s where each one takes the data from one piece of equipment. The equipment is such that they are both constantly outputting data. I have been successful in running both of the sub VI�s separately at the same time. The trouble occurs when I try to put the sub VI�s together in a larger VI. When the two sub VI�s part of a larger VI, both cannot run at the same time. One of the sub VI�s tries to read from the serial port and is unable to get anything in response. Is there something I am missing as to why they can not be running at the same time?
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Hello,

It is possible that you are seeing the consequences of LabVIEW compiling code written in parallel. More specifically, if you have code in parallel (not connected by dataflow, but in the same block diagram) LabVIEW will split execution time between those parts of your code. Previously you were likely manually starting two separate programs, which inherently adds a delay between the start of the programs, allowing the first program to get sufficiently far in its execution; we could be seeing the consequence of this. It would help if you could be more specific about the details of your setup and code (such as 1. which instruments are connected to which ports? 2. are you writing a command to your instruments and then receiving data as a response? 3. do you rec
eive any errors? 4. if you do receive errors, which errors do you see and where in your code do you first see them?).

Repost with some more information (perhaps a screen shot or your code) and we can get a more definitive answer!

Thank you,

Regards,

JLS
Applications Engineer
National Instruments
Best,
JLS
Sixclear
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