ni scope EX configured acquisition cursor readout

[kuchean]

I am trying to build my own version of the NISCOPE soft front panel using a 5114 high speed digitizer board.

I started from the NiScope EX configured acquisition example, and I can grab and display the waveform alright,

but I can't get the cursors to update their current positions. I created a cursor property node on the xy graph

and I am trying to read both the x and y positions to get both voltage and timing information from the acquired

waveform. I can drag the cursors around the graph but the readout of the cursor positions only appear to change

during the second or so the graph is being written to.

Kuchean

[The_Red_Barron]

Howdy Kuchean!

In the niScope EX Configured Acquisition example try right-clicking on the graph>>Properties>>Cursors tab then select the "allow dragging" option and choose "single-plot" from the drop down menu.  This will allow you to drag the cursor around and read the x/y values using the Cursor Positions property node.  This should allow you to move the cursors whenever you want to and you will receive their current position when reading the property node.

Also, what is your reason for trying to recreate the Soft Front Panel rather than just using it?  Is there a specific functionality that you are trying to achieve that is not supported by the Soft Front Panel?

Regards,

[kuchean]

1. The problem as I found later, is that the reason that I can't get the delta between the cursors is because the program is mostly hung up

     waiting for aquisition to complete. I had to set the timeout to 50 seconds to aquire and try to manipulate 500k samples making up three

    seconds or so of waveform. An indicator wired to the iteration counter executes once during the time the program runs. 

2. I want to use the cursors to measure amplitudes and timing of various parts of the waveform envelope, and eventually isolate subsets

    of the  waveform for RMS and peak to peak measurements.

Kuchean

[The_Red_Barron]

I still do not fully understand what changes you have made to the niScope EX Configured Acquisition example that is causing it to hang up on you.  What sample rate are you using and what other settings or parts of the program have you modified from the shipping example?

From an unmodified version of the niScope EX Configured Acquisition VI I added two cursors to the graph (Right click on graph>>Properties>>Cursors tabs>>Add).  I configured them to allow dragging on a single-plot.  In the loop on the block diagram I added a property node to get the cursors list, then broke out the data to get the X and Y coordinates for both of my cursors.

If you can describe what specific changes you have made to the niScope EX Configured Acqusition then I may be able to help you better.

Regards,

[kuchean]

The program hangs even without change. Aquisition rate: 125ks/s.  Min record length: 500K. Timeout 50 s.

The program always stops on an error message, that it timed out before the acquisition had completed.

Thie timeout is actually one of my biggest problems since the Soft Panel Oscilloscope has some way of running

until either stopped or paused without timing out. 

Kuchean

[The_Red_Barron]

What settings are you using to configure the trigger and what are the characteristics of your signal?  If you are trying to use an edge trigger but the signal never crosses the threshold then it could result in a timeout.  Does the timeout error still occur if you use the immediate trigger setting? Also, what is the error number of the timeout message you are receiving?

Regards,