How do I plot a third voltage channel

[T.Ferg]

In this VI, I have one voltage(representing current)  input plotted as a function another voltage channel (potential).  What I would like to do now is to add a third voltage channel (representing another current).  I would like to plot it in the same manner.  The plot can be on the same graph or another one.  Can anyone offer some suggestions?

Thanks,

T. Ferg

[phil_prismtc]

To plot a third or indeed any (extra) channels, you simply need to index them from the acquired data (from DAQmx Read) and bundle them into a cluster. The bundled clusters then get built into an array in order to plot them on the same X-Y graph. See my ammended VI 'cyclic3 Multi plot.vi'.

One thing I should point out is that you have an unbounded array that increases in size by (1000x No. of channels) elements every time the while loop executes. If this loop is left to run for extended periods of time, you may run into memory/performance problems.

Hope this helps.



Phil Duncan
Certified LabVIEW Developer
Prism Technical Consulting

[devchander]

Hi T.Ferg,

I have modified your VI to add one more XY plot to the same  XY graph

have a look at attached VI,

Just make sure your acq does not load the shift registers

regards

Dev

Message Edited by devchander on 12-20-2005 10:41 PM

[T.Ferg]

Phil, the reason this VI runs 1000 times each time the while loop executes is that I need to able to run multiple cycles.  For example, the applied voltage range is from -1V to 3V.  A potentiostat would sweep from -1 to 3 and then from 3 to -1.  This would be one complete cycle.  I was also trying to figure out a way that I could control the number of cycles this VI executes.

Message Edited by T.Ferg on 12-21-2005 09:30 AM