How do I graph multiple bit values on one time axis?

[diarmaede]

I want to graph multiple bit values, all of which will change back and forth from 0 to 1, on the same time axis, but I don't want any visual overlap between the different bit value traces.  Now I could do this by graphing bit one as either 0 or 1, bit 2 as 2 or 3, bit 3 as 4 or 5, etc., but I would really rather have multiple Y axes showing 0 to 1, stacked vertically on the same time (X) axis.

You could visualize this as multiple pens on a strip chart continuously recording different values.  Each pen has its own vertical area in which it writes, but all pens could be writing data from the same numerical range.

Hmmm...  I think my description might be roughly as clear as mud, but if anyone out there can figure out what I am asking and has potential solutions, please let me know.

Thanks!

[Darin.K]

My first inclination is to see if the Digital Waveform Graph will do the job for you.

[diarmaede]

Thanks!  That is helpful.  But is there a way to plot the digital data against another array of time values, rather than assuming a standard delta T?  I have timestamps associated with each recording of the bit values, and I would like to use those timestamps as the X axis of my graph.

[Verne_D]

Take a look at the Build Waveform VI in Programming > Waveform > Digital Waveform. You can easily set a t0 and dt. to match your data.

[diarmaede]

Thanks.  I will look at that VI, but I think I have already seen it.  My problem is that I have CAN data coming in for an hour or so, but the time interval between receiving specific CAN arbitration IDs varies, so I want to plot the X axis against specific, varying time values, not a standard dT.  I'm not sure I can do this on a digital graph, but I haven't given up hope yet.

BTW, I am receiving 8-byte CAN packages.  Some of the bytes represent actual values, but I need to break others up into individual bit values to see error and status flag settings.  Once I break the bytes into bits, I convert from analog values to digital values.

[Verne_D]

If you're using analog data, you can look at an XY graph. It's not as clean as the digital plot, but using nonstandard time arrays for the X-axis is pretty straightforward. Think scatter/line plot.