chart reading 5 second intervals

[Rob.Judd]

i have an ozone monitor that puts out data about every 5 seconds and nothing in between. i'm plotting the ppbs on a waveform chart but it updates every second, reading the "no data" as zeros. how do i change it only to update when it receives data? (As you can probably decipher, i am a beginner at LabView) Thanks!

[Dennis_Knutson]

Without having any details on the instrument and how you're interfacing to it, I can only give you some general direction. If you have a while loop in which you are updating the chart, put another while loop inside that will exit when there is valid data or you stop it. Wire the data read to the graph indicator outside of the inner while loop. Post your code or additonal details if you want an example.

[Rob.Judd]

Dennis,
I am using the 2B technologies Ozone Monitor. I have attached the .vi file for it. I have also attached the output file. If you have any ideas on how to get rid of the extra returns in the output file, I would appreciate it. (I'm sorry about my extremely limited knowledge, I just started working in LabView on Tuesday) Thank you so much for your help.

[Rob.Judd]

check that, the monitor gives data every 10 seconds, but data shows up on the chart every 5 seconds.

[Rob.Judd]

never mind, i figured it out. thanks!

[Dennis_Knutson]

Glad you figured it out. Pretty good for only one week. I would suggest that instead of using the Write Characters to File inside the while loop, skip the close file you have outside, pass the refnum from Write File to another Write File inside the while loop, and then pass the refnum from that to a Close File outside the while. That way you're not constantly open and closing the file and you'll get better performance.

[JohnX]

Hello,

  I am trying to configure the 2B ozone monitor to labview as well.  Labview reads the data from the ozone monitor (2B manual says the monitor puts out dadta as ASCII) as underscores and "x" (___x_x__etc.).  Do you have any advice or tactics to configure the ozone monitor to labview. Any help would be much appreciated.

Thank you,

John X