absolute time in mixed signal graph

[wayoversampled]

I'm trying to build a mixed signal graph with 4 inputs (Temp, Temp setpoint, %RH and %RH setpoint).  I'd like the X axis to be absolute time, but not sure how to wire it correctly.  From searching the help files and discussion forums I gather I have to include a timestamp as a DBL.  So far I have created the following 3 scenarios:

• All four inputs work but x axis is relative.
• Two inputs work and x axis is absolute time (below) 
• Same with 4 inputs breaks graph with an error that the number of cluster inputs does not match (far below).  ???

I seem to be missing something basic.  I would greatly appreciate anyone's help...before the computer gets it! 

PS LV8.5/WinXP Pro

Message Edited by wayoversampled on 09-29-2008 08:08 AM

[Cory_K]

Why isn't this working -->

- Right click on the graph 

- Click 'Properties"

- Go to "Format and Precision"

- Select x-axis

- Select "absolute time"

[wayoversampled]

Thanks for the reply, but I have already double-checked this.  Any other thoughts are appreciated.

[wayoversampled]

Just to add...I tried several more variations by building arrays instead of bundling into a cluster with no avail.  I also tried the same vi's in LV8.2.1 to see if it is a bug in 8.5, but didn't help either.  I'm relinking the pics again below.  If anyone knows a link to some more info on mixed graphs that may help too.  I've only found one with absolute time and it didn't really help for what I want to do.

2 inputs (works with absolute time):

4 inputs (doesn't work):

Thanks again...

[chris.b]

Could you go ahead and reattach that image (C:/Documents and Settings/herrickm/Desktop/smash computer.gif) to this post ("Insert/Edit Image" in the toolbar above the textbox)?

[chris.b]

Thanks for the images.  Could you post one of the first scenario, "all four inputs work but x axis is relative"?

Message Edited by CXB on 09-30-2008 12:39 PM

[chris.b]

Message Edited by CXB on 09-30-2008 01:37 PM

[wayoversampled]

I will attach another image of the one with relative time this evening.  Notice on the example you provided, the times all read December 1903.  How do you get around that?  That's why I had the timestamp converted to DBL piped in...though i'm not sure that's the right thing to do.

[wayoversampled]

Here is a simplified version of my working application.  Each iteration of the loop polls 4 analog inputs- Temperature, Temp setpoint, %RH and %RH setpoint and 6 digital inputs.  This currently works.  I can't seem to just add a timestamp as a DBL, it only shows up as another plot.  This will only work with a relative time, or the absolute time shows up as 1903.

The computer is about to get the worst of this 

Message Edited by wayoversampled on 09-30-2008 07:51 PM

Message Edited by wayoversampled on 09-30-2008 07:54 PM

[maat · Accepted solution]

There seems to be an issue with the x-axis time when you input the arrays of analog data and the waveform of digital data. Try the attached vi where you are piping the analog data in as waveforms. This will still let you watch the data while it is being collected over a period of time, which is what it looks like you are trying to do. It also has a clear function. My example is rough; it would probably be better done with producer-consumer loops or an event loop to make it more efficient. Let me know if it doesn't work.