2 DAQ Assistants, 1 Front Panel Graph

[lccarey]

I'm running LabView 7.1 with an NI USB-6251 hooked up to an UniMeasure, Inc. HX-EP-80 Quadrature encoder and a small pressure transducer.  The transducer (Pressure vs. Time) and encoder (Depth vs. Time) are both processed through seperate DAQ Assistant Express VIs within the same block diagram and can be displayed as wave graphs separately on the front panel.  Both transducer and encoder write to an excel file at the same rate, from which I can create a Pressure vs. Depth graph, however, it would be really nice if I could get such a graph to display on my front panel in real time as the VI is run.  I've done some experimentation with the 'Select Signals' and 'Split Signals' Express VIs without any success.  Any advice would be appreciated. 

[Wire_Warrior]

lccarey,

If I understand what your saying what you would like to do is skip over the step where you export the data to an excel file and go straight to the graph generation.  What you need to do is drop a XYGraph control on to your front panel separate out the data Pressure data (- the time) and the Depth data (again without the time), bundle both of those data arrays into a cluster and then wire that cluster to the graph control.  You may have to switch your bundling order to get the x-axis/y-axis content you want.

To split the data out you should probably use primitives, either "Unbundle" from the cluster palette or "Index Array" from the arrays palette, depending on the structure the DAQ Assistant uses to return the data.  I can't be more specific since it's been a long time since I have used 7.1 and I don't have it installed on any machines.

See the attached image for how simulated what you need to do in LabVIEW 2010.

Good Luck,

Jason