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maartendm
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convert serial data into analog waveform

Hi,

I'm reading in some analog signals with labview 8.5 from some sensors through an ADconverter which then sends the serial data through a virtual COM port into labview. I'm using the VISA drivers to get this done. Works pretty good, but now I'd like to perform some signal processing on this data. I want to do some filtering and measuring on my signals such as phase, amplitude, frequency. Problem is most signal processing vi's are suitable for analog or digital waveforms, while I'm dealing with unsigned word. So how do I convert this unsigned word signal into an analog waveform signal? I figured out I need some sort of timing information, corresponding with every unsigned word I acquire. How do I add this timing info to the unsigned word to assemble the analog signal I need? Or am I missing a clue here? I'm pretty new to labview...

 

best regards

Maarten

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Re: convert serial data into analog waveform

Look at Build Waveform on the Waveform palette.  It bundles together an array of data (which you would have built from your incoming data), a T0 timestamp of the starting time, and a dT which is the time period between samples.  The result is the waveform datatype cluster.

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maartendm
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Re: convert serial data into analog waveform

thanks for the help!

I tried the 'build waveform' already, but I couldn't figure out how to assemble the data array and what timestamp to use?

 

best regards

Maarten

 

 

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Re: convert serial data into analog waveform

Use build array to build new elements onto the end of the array and store it in a shift register from iteration to iteration.

 

For t0, use the time when you take your first sample.