Making a graph act like a chart

[vgravel]

Hello all,

I would like a graph that would act like a chart...

What I mean is a graph that will update quite the same way than a chart does (strip or scope). The reason why I don't simply use chart is because I need the graph's annotation (not availabable with chart) and I need to be able to scroll back and to see the complete waveform since the begining of acquisition.

What I've tried is to use the 'Xscale - Range - Start' propertie and to update it every time I update my graph. The problem is that we see this change so the graph is flashing (to resume, we see nothing).

Anybody have an idea of how to implement something that would do the trick. I have been looking around but with no luck.

Thanks in advance!

Vincent

[altenbach]

Can you show us your code?

Where do you keep the data history?

[vgravel]

Hello Altenbach,

First thanks for interresting yourself to my question.

The front panel is part of a pretty big projet... The data history is kept in a functional global variable (VI with uninitialyzed shift registers holding a array of waveforms). The picture will give you a idea.

I have a timed loop to display the data on my front panel. The data is collected in another VI in a timed loop of higher priority.

Thanks again!

Vincent

[vgravel]

Anyone?

[tst · Accepted solution]

I posted an example here. I can't look at it now, but it uses the same basic method you do (although not with a waveform), and if memory serves it doesn't flicker.

In any case, if you want to avoid the flicker, you can try using the Panel class property Defer Panel Updates. Set it to F before writing the value and to T after.

[vgravel]

Thanks tst for your reply.

I didn't know about this property. I'll try that and I will probably do the job.

Thanks again, I'll give you a Kudo for that!

Vincent