Visualizing 16 bit digital data on one DI line?

[GerdW]

Hi maverikk,

as has been said before: DON'T create a 16-bit waveform from your data! This one expects to use 16 DO channels to send out the data!

You need to serialize your data to be able to send them over just one DO channel. Didn't we discussed that before?

[maverikk]

Hi GerdW,

Yes I tried that way as well. Attached is the VI. I am getting an array of 15001 x 16 while I wanted an array having just one row and 15000x16=240000 elements in that. Please tell me where am I wrong.

[GerdW · Accepted solution]

Hi maverikk,

did you read the help for BuildArray? Did you notice the concatenation mode it supports?

Two different options shown in the image.

(I'm not sure your LabVIEW2014 already supports concatenating output tunnels…)

[maverikk]

Hi GerdW,

Yes it supports concatenation. Thanks to you I got the data in 1D array having 240000 elements. Now I want to transmit it via a DO channel so I converted it into a digital waveform. Its transmitting without any error and on a single DO channel but at the receiver side no output is visible.

[GerdW]

Hi maverikk,

why don't you use BuildArray (and TransposeArray) to create a 2D array from your 1D array of booleans in "serialize"?

Why do you use that DAQAssistent?

Why did you set a samplerate of 1MHz in the DAQAssistent?

Why do you read at just 1kHz samplerate in your Rx VI?

How do you synchronize your Tx and Rx routines?

[maverikk]

Hi GerdW,

That was an older program so I used that to convert to digital waveform. Digital waveform, so that I can cross verify the received signal with the transmitted one.

I am using 1 MHz sample rate randomly because no. of samples are 240000.

Latest VIs are attached. But this also is not showing me any output. I am very new to digital domain in labview. How can I test a sample digital signal by doing loop back? I don't know how to test DIOs. I have used test panels to check all the AIs, AOs and counters. They are working fine. 

[maverikk]

Hi GerdW,

I can not take the signal out of the DO line. I want to first visualize the serially converted data on an oscilloscope. I am wondering can aperiodic digital signals be realized on oscilloscope? Also I want to use onboard 8 MHz clock for triggering purpose. I have searched online for info. but didn't find much. Please guide me through.

[GerdW]

Hi maverikk,

I can not take the signal out of the DO line.

Why not? Any errors in your VI?

To learn how to use DO channels you could examine one of those DAQmx example VIs found in the example finder…

I want to first visualize the serially converted data on an oscilloscope. I am wondering can aperiodic digital signals be realized on oscilloscope?

Usually yes.

Read the manual of your scope for more detailed information.

Also I want to use onboard 8 MHz clock for triggering purpose.

Which board?

Which "triggering purpose"? What do you want to trigger?

[maverikk]

Hi GerdW,

Attached is my transmitter vi. Please check what am I doing wrong. Its frustrating. No output is coming at DO line and neither on oscilloscope.

[maverikk]

Hi GerdW,

This is corrected vi. Now I think I am receiving the data.  Data is being received but it gets past too fast to realize. I have made the transmitter and receiver vi in the same block diagram to take care of the synchronization issue. I need to store and compare the received and transmitted data to cross verify whether is it same or not?

Where am I wrong? I am transmitting and receiving at the same data rate.