Discussion:
Continuous charts
(too old to reply)
Sumeet
2009-01-16 03:15:06 UTC
Permalink
Hi,

I'm new to labview. I'm facing a very basic problem.

I need to measure temperature, and I'm using the 9172 chassis and 9217
module to do that using RTD's. Now, in labview, I added a DAQ
assistant, and set the samples to continuous with a sampling rate of
1Hz. I need to plot this data. However, when I connect a waveform
chart (strip chart) it displays the data for 5 secs, keeps it stagnant
for 5 secs, then displays new data after 5 secs and so on. It doesn't
display it continuously. Also, increasing the X axis from 0 to 20
doesn't help, it still displays data only in the first 5 secs of the
graph (and refreshes that portion) i.e. it displays temperature for
the first 5 secs at 1 to 5, then temp for next 5 secs is also
displayed at 1-5 deleting the old data and so on. The portion of the
graph from 6 - 20 is always kept blank.

I want to set it up so that it displays a new data point as soon as it
gets one. To achieve this, I changed the no. of samples to 1 (from 5
as set above). However, now it displays just 1 point, increasing the x
axis from 0 to 20 doesn't help. How do I set it up so that it displays
a continuous scrolling display like an oscilloscope.

Thanks,
Sumeet.
Freelance Embedded Systems Engineer
2009-01-17 16:39:58 UTC
Permalink
Post by Sumeet
Hi,
I'm new to labview. I'm facing a very basic problem.
I need to measure temperature, and I'm using the 9172 chassis and 9217
module to do that using RTD's. Now, in labview, I added a DAQ
assistant, and set the samples to continuous with a sampling rate of
1Hz. I need to plot this data. However, when I connect a waveform
chart (strip chart) it displays the data for 5 secs, keeps it stagnant
for 5 secs, then displays new data after 5 secs and so on. It doesn't
display it continuously. Also, increasing the X axis from 0 to 20
differences between charts and graphs:
http://www.icon-tech.com.au/faq_frontpanelobjects.html
Post by Sumeet
doesn't help, it still displays data only in the first 5 secs of the
graph (and refreshes that portion) i.e. it displays temperature for
the first 5 secs at 1 to 5, then temp for next 5 secs is also
displayed at 1-5 deleting the old data and so on. The portion of the
graph from 6 - 20 is always kept blank.
You'll have to change the buffer size as well.
Post by Sumeet
I want to set it up so that it displays a new data point as soon as it
gets one. To achieve this, I changed the no. of samples to 1 (from 5
as set above). However, now it displays just 1 point, increasing the x
axis from 0 to 20 doesn't help. How do I set it up so that it displays
a continuous scrolling display like an oscilloscope.
Thanks, Sumeet.
See "Real-Time Chart.vi in the Labview Examples

Continue reading on narkive:
Loading...