2D U16 vs 1 d Wfm in Nchnl Nsamp

Hello

I tried to do a multiple channel with PCI 6229 Council 2090 BNC data acquisition work. After you have created the virtual channel and start the DAQ task when I acquire the signal, I get a strange behavior. I give a square input signal of 1 volt and zero volts.

When I use the 2D U16 Nchnl Nsamp: I get peaks in amplitude constant for the zero volt part, where there are reading the 1 volt portion correctly.

Whereas when I use the Nsamp of Nchnl of Wfm D 1: I get about the signal that is entered into the system with a behavior of square wave and a suitable voltage range.

Please suggest as to what is the difference between the two conditions, and perhaps why am I cleats for the zero volt part.

Concerning

Amanmeet Garg

Graduate student

Simon Fraser University

Burnaby, Canada.

Thanks Dennis,

Your reference is a good information. I was able to solve my problem by keeping the acquisition as a signed integer of 16 bit, as I am able the negative tensions as well.

therefore in the region of zero volts /-EV system was him giving a value of 65535 in case of unsigned 16-bit sampling.

I'm balance correction and external filtering in MATLAB and get reasonable results.

Concerning

Amanmeet Garg

Tags: NI Software

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