Plot data to chart with real time axis

[rty]

Hi,

I want to plot some data from rs232 to a chart with a time based axis. I made something like the example "Variable-time Chart XY" but im getting an error : "connect 1-D array cluster of 1 element to sink cluster of 2 elements".

What shoud i do to fix this?

Thanks in advance

[Ray.R]

You have two different types wired to the same waveform graph.

 

You have a cluster of DBL/SGL/SGL/SGL/DBL and an array of clusters[SGL/DBL].

Question:  Why is your code so complicated?  What are you really trying to do?  I'm sure there is a much simpler way of doing it.

R

Message Edited by Ray.R on 12-09-2009 01:12 PM

[rty]

I want to plot data to chart with time axis,

I made this and its ok, but now i want to show time on X axis.

[Ray.R]

Problems:

You have a race condition.  Two sets of values being written to the same graph in parallel. I realize that you want to send the X-axis seperately, but to what values are you associating those values to (on the y-axis)?

What does the data from the serial port look like?  And why do you use a byte array?  Is the data all binary?

If so, maybe the first step is to determine the start & end of a byte array and convert it into numeric.   You read it in 12 bytes, why do you do that?  Can you ensure that it is the full / proper data frame?  Are there any delimiters or patterns to indicate start / end of data?

Why do you add zero to the strange timestamp?  0 does not change the value.  You're adding the strange timestamp to the data going to the graph... That's going to make things ugly..  Not only in the esthetics sense 😉

You should bundle the timestamp with the data in a waveform.  I would suggest a smaller number for the timestamp, but that might be a requirement that you are trying to meet.  

You need to describe what you want to do before getting help with this.

R

EDIT:  I type too slow, you've made some improvements while I was typing...  😉

Message Edited by Ray.R on 12-09-2009 01:30 PM

[Ray.R]

---

rty wrote:

I made this and its ok, but now i want to show time on X axis.

---

You mean to tellme that the above code works and you are getting the desired plot? 

Maybe I am missing something, but you are probably getting to points and maybe a straight line between them.  Is this correct?

All you want to do is add a timestamp to those two points?  Is that correct?

[rty]

ok, forget about the time problem and lets focus on rest first.

I have this:

Im sending many types of data to rs232 (XY acelerometer values, temperature, and others). in the chart example, i send from hardware something like "x%0.2fy%0.2f" where 0.2f is the value and the x/y is a tag that help me to know what kind of data is that.

So when i receive, firstly convert the string to an array and then i serach if the first position of array is an "x", if so then i know that string has data that i want to plot on chart. It enters on a case structure and then i split the array to "x%0.2f" and "y%0.2f, i remove the "x" and "y"and convert the data to decimal string to plot on chart.

This is working fine, i belive there are many easiers ways to do this but im begginer with labview!

Ok, now i have 2 plots on the same chart and i want to set the X axis as current system time (HH:MM:SS,xx).

Thanks for your help and forgive me my bad english

 ---------------------------------

EDIT:

Yes, as far as i know it's working 🙂 

Message Edited by rty on 12-09-2009 01:03 PM

Message Edited by rty on 12-09-2009 01:05 PM

[aeastet]

You can use an XY graph and get what you are looking for. See blow

[rty]

and how i get the time ? with the get data/time string of timing palette?

[aeastet]

That would work.

[rty]

u mean this ?