04-05-2018 08:56 AM - edited 04-05-2018 08:58 AM
Well, I would like to know how to get multiple analog inputs from a circuit and show their value. In the enclosed circuit I want to obtain in one daq the voltage "Vc" and in another daq the voltage "Vb".
In doing so there is an error indicating that we must use "Multiple channels" to do what we want.
We currently have 2 daqs with which we generate the voltage Vcc (5v) and Vbb (3v).
04-05-2018 09:15 AM
Hey Jose,
What hadware do you have ?
What is the exact error you get ?
Thanks,
04-05-2018 09:21 AM
Hello jose,
some advices :
Use the data flow of LabVIEW to generate firstly then acquire your data.
Use error handling.
To acquire data on 2 channels by using DAQ assistant : at the end of the configuration, select the two channels that you want to have>then, use your graph to visualize datas of the two channels, you can use convert data (Express>>sig Manip) and choose 2D array if you want to see your data in 2 columns of an array.
Kudos are welcome!
04-05-2018 09:23 AM
What hadware do you have ?
National Instruments (NI USB-6008)
What is the exact error you get ?
the conflict is when using two analog inputs (DaqAssistant and DaqAssistant2)
04-05-2018 09:31 AM
According to the error you get, yes you should follow Fred's advice above.
When you want to acquire 2 different channels at the same time, just "bundle" them under the same Task. You can do so during the configuration of your task by selecting two or more channels in the provided list. If you don't do that, then the second Task will try to access the device which is already use by the first Task and return an error.
Here is a document you might want to read : https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000P8b1SAC
04-05-2018 09:49 AM
I strongly recommend you spend a little bit of time and learn how LabVIEW works with DAQ (Data Acquisition) devices -- it does not involve the Dreaded DAQ Assistant (and its Evil Twin, the Dynamic Data Wire (both of which you have in your picture -- I'm not going to do my standard Rant about how I hate "pictures of Block Diagrams", and really want VIs to be attached ...). Here are some recommendations:
Using "real" DAQmx and Tasks instead of the DDA (Dreaded DAQ Assistant) will make your code "lean and mean", easier to understand and debug, able to be probed (tested) and flaws located/fixed, and you will have a much more professional piece of code (and will learn more about LabVIEW).
Bob Schor