Using SBC4 through wifi to read remote spatials

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chedas
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Using SBC4 through wifi to read remote spatials

Post by chedas »

Hi
I create a hotspot with my laptop. Then I connect a sbc4 to this wifi hotspot. With my laptop I can run a labview program that acquire data from the spatials connected physically to sbc4. The program works fine.

The problem is that with one spatial 1042 running at 250 Hz sampling frequency I get a delay of 20%. With 4 spatials I get 50% delay...this means that acquiring 20 seconds of data what are saved are the first 10 seconds.

These numbers are normal? What can I do to improve?

Thank you
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Patrick
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Re: Using SBC4 through wifi to read remote spatials

Post by Patrick »

Are you using events, or polling? For something like this, where you want to acquire all data without gaps, it's really necessary to use events.

-Patrick
chedas
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Re: Using SBC4 through wifi to read remote spatials

Post by chedas »

Hi Patrick
Yes. I am using events.
chedas
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Joined: Tue May 08, 2018 9:06 am
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Re: Using SBC4 through wifi to read remote spatials

Post by chedas »

One more thing.
If I connect the four spatials directly to my laptop, without using the sbc4 and the wifi, I do not get any significant delay (~0.01%).
Obviously, if we add more functions to our program during acquisition at some point we start having delays.
What is strange is the fact that for the same program the sbc4 and wifi increment significally the delay (~40 to 50%).
Is this normal?
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Patrick
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Re: Using SBC4 through wifi to read remote spatials

Post by Patrick »

Hi,

Are the phidget libraries on the SBC4 up to date?

Are there any errors in the network server log on the SBC? (at /var/log/phidget22networkserver.log)

-Patrick
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