visa sessions

[sadia]

Actually i am using labview to acquire real time data from rigol oscilloscope
DS1204B.I succeeded in acquiring waveforms but my problem now is to first get
data of a waveform and get its amplitude1 value and then get another waveform  
and want to use amplitude1 of previous waveform to get amplitude of second
waveform divided by amplitude1. So basicaaly i want to store that previous
value of amplitude1 of first  waveform. First i get waveform1 data and its
amplitude but when i display the second waveform on rigol and acquire it in
labview my previous data is lost that was amplitude1....so kindly give me a
solution to this problem so i can be able to acess my  previous stored data in
next acquisition.

[Sam_Sharp]

Use a shift register or feedback node to save the value from the last loop iteration. If you want more detail than that, post your code!

[Hatef.fouladi]

also you can use Append Waveforms VI for waveform and attach your file with shift register
or use what Sam told and use insert into array instead

[Dennis_Knutson]

Hatef,

What would be the point of either the Append Waveforms or Insert Into Array? Neither would be appropriate based on the op's description. A single shift register as Sam mentioned is enough.

[Hatef.fouladi]

dont you need to save your data based on time index? using just shift register will be destroy last data and you would not have a access to them

[sadia]

Details are provided in second math script palette used in attached vi

[Dennis_Knutson]

Can you attach an image of the block diagram? I'm posting from my phone.

[sadia]

different parts of my vi

[Dennis_Knutson]

I don't understand what you are trying to do. When you say waveform 1 and waveform 2, do you mean channel 1 and channel 2? Or do you mean to repeat the acquisition of both channels? And I would eliminate the Mathscript and use native LabVIEW functions.

[sadia]

I mean to repeat acquisition of both channels for new waveforms displayed on oscilloscope