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Can't aquire two channels?

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I'm missing something...I can't seem to aquire mutiple channels. It'll work if I delete one of the channels.

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Message 1 of 14
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First get those error clusters on shift registers so you can see what error you are causing when your read vis try to commit the same timing resouce.

 

You won't be able to reserve the same timing resource for two tasks.  but, you can have multiple channels in 1 task


"Should be" isn't "Is" -Jay
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Message 2 of 14
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If I delete the other channel creation and create another "read" inside my while loop which connects to my first channel creation...how do I stipulate which channel number this new "read" is?

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Message 3 of 14
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Solution
Accepted by topic author glskinner

@glskinner wrote:

If I delete the other channel creation and create another "read" inside my while loop which connects to my first channel creation...how do I stipulate which channel number this new "read" is?


Not quite.

 

Create the task with two chanels and then your read reads and returns data from both channels in an array of waveforms.  Simply index out the waveform you want.  (Or graph them as seperate plots on the same chart)


"Should be" isn't "Is" -Jay
Message 4 of 14
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something like this?

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Message 5 of 14
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@glskinner wrote:

something like this?


Yes.  But,  Start preserving those errors!

 

(Shift registers will reall save a lot of debug time in the future until you write error free code like me) Smiley LOLSmiley LOLSmiley LOL


"Should be" isn't "Is" -Jay
Message 6 of 14
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ok, thanks for your help on the mutiple channels...Now you're saying wire my error boxes that I have outside my while loop to the shift registers?

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Message 7 of 14
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right click the error tunnels replace with shift registers.  error in and error out of loops should always be on shift registers so that if 1 loop iteration causes an error it is passed along to the next iteration and the error information is not lost.


"Should be" isn't "Is" -Jay
Message 8 of 14
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@JÞB wrote:

right click the error tunnels replace with shift registers.  error in and error out of loops should always be on shift registers so that if 1 loop iteration causes an error it is passed along to the next iteration and the error information is not lost.


Except it will keep any later iterations of the loop from ever executing properly considering most functions are designed to not execute in the event of en incoming error.  You'll never get the loop to run properly again unless you restart it, or handle the error and clear it.

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Message 9 of 14
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@Bill exactly! if an error occurs something happened that needs interaction. what could this be?

The developer wrote a bug and the vi cannot work that way. tossing out the first error is a critical mistake.

the device has an unexpected limitation (Buffer overflow or USB power management disconnect) . the app may need recovery code or the system could be set up better. tossing out the error is a critical mistake.

operator error. like my worst ever fault isolation problem (SET SEASTORY )

The USS California's air search radar was suspected to be haunted. three out of four days the VSWR alarm would go off at 17:00 hrs sharp (ruining some poor techs dinner guaranteed) . This went on for over a year before I suggested we log the occurrences too see if there were any patterns.... Yup we saw the pattern in short time. A brief walk through Officer's country at the right time allowed me to address the LTJG and explain the difference between a waveguide and a chin-up bar. (Exit SEASTORY ) Error information is critical.

"Should be" isn't "Is" -Jay
Message 10 of 14
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