USB-6009 analog input at certain voltage

[Ace666]

i am using USB 6009

i want to use a certain voltage to activate something.

i want to activate a pop up vi inside a case structure at a voltage of 2.9V.

i want to de activate the case structure at a voltage of 0.13mV - 0.16mV . then the sub vi will close.

How to setup the DAQMX?

can provide any help ??

example will be good.

pls show where to find the icons. thank you

[Jennifer O]

Hi Ace,

If you set up your device to acquire continuously, you can feed your signal to an Express VI named "Mask and Limit Testing".  If you set your high and low limits you will get an output signal called "passed".  You can use this signal to determine if the signal was outside or within the limits you desire.  can use just a single upper or lower limit or both in this function.

To locate this function, you can press the "search" button on your pallette.  Search using the name above.  There are also low level functions you can use.  Searching "limit" should bring these up for you to experiment with. 

If you set up your application with several states this will be a simple application.  If you are unfamiliar with state machines you can learn about them here.  You can have one state to wait for the 2.9 condition, a state to cause the popup, a state to wait for the close condition and a state to close the popup.

I hope these suggestions will help to get you started with your application.  If you have any questions regarding the state machine or any of the limit functions do ask.  I hope I have not mis-interpreted your question.

Regards,

Jennifer O.
Applications Engineer
National Instruments

[Ace666]

is there any examples on that mention about ?

is there other ways beside that ?

[MissyS]

Hi Ace,

There are several examples from the LabVIEW Example Finder (Help»Find Examples...) that describe using limits. I searched "limits" in the Example Finder and found several examples that might help, such as Limit Testing Measurement.vi, Waveform Scalar Limit Comparison example.vi, and Limit Example.vi. In each, you would have to modify it to include data acquisition, but it shows how to take sampled data as you would get from data acquisition and perform a limit test. The Express VI that Jennifer O. suggested will probably be the easiest route, but there are other VIs that could suit your needs, as seen in the other examples. 

As far as state machines, there is a template built into LabVIEW that can give you a starting point for creating your own state machine. Under the File»New... menu, you can choose the state machine template under VI»From Template»Frameworks»Design Patterns»Standard State Machine template.

Please let us know if you have any specific questions we can answer about configuring your data acquisition or about a specific VI. I hope this helps!

Regards,

[Kodeeswaran]

hai ace,

            you want to compare the direct voltage or scaled units,

its easy to compare and check the condition.

[Ace666]

for example .

i doing a voice activated switch.

once i say HI, the voice activated will give a currect output voltage. e.g 0.13mv

how am i going to set this 0.13mv so that i am able to activate a case struture or a event struture ?

[Jennifer O]

Hi Ace,

Not sur if you are still workin on this, but it would make sense to just use a greater than function ouptut a boolean true or false.  The boolean with feed the case structure where the message pop-up function sits.

Let us know if you still need some help.

Regards,

Jennifer O.