Understanding labview fpga using sbRIO

[thoult]

If it's configured for single ended acquisition and not connected to anything, it may well exhibit this behaviour. If you short between AI0 and 0 V, you should read a constant ~ 0 V.

Stupid question, but are you actually passing a voltage through the potentiometer?

You're much better off connecting a known voltage source between AI0 and AIGND (if single ended). A 1.5 V AA cell, or a 5 V DC power supply, or 5 V from a USB cable, for instance.

[kdm7]

Hi,

Oh yes! silly me.

Thanks

I can use the 5V supply pin of the sbrio right?

[crossrulz]

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kdm7 wrote:

I can use the 5V supply pin of the sbrio right?

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Yes you can.  But you might want to use a separate power supply so that you can vary it and make sure your voltage reading changes.

[kdm7]

Now I am able to see the varying voltages, but the polarity is changed. I get negative values instead of positive.

My voltmeter reads positive voltages. That means something is wrong with the VI right? 

I have attached the project.

[GerdW]

Hi kdm,

That means something is wrong with the VI right?

My first guess for such problems would be: Is the wiring correct?

Did you check this? Did you do a cross-check? Did you have someone else cross-check this?

[crossrulz]

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GerdW wrote:

That means something is wrong with the VI right?

My first guess for such problems would be: Is the wiring correct?

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That was my very first thought.  Almost always when your read data is inverted, it means you swapped your signal and ground in the wiring.

[thoult]

It would have been more appropriate if Henrik_Volkers had been the one to point that out 🙂

[kdm7]

I interchanged the wiring. Now it reads positive. (but have to check the pins as I have a ribbon cable connected to the connector and then to a PCB with phoenix connectors.)

[kdm7]

Hi all,

Now I'm trying to log the data over the server through ftp protocol. 

Can anyone provide necessary links to learn?

Do I need the Internet toolkit? (I do not have it.)

Can I use the FTP put file?