What does it mean by "synchronous display"?

[?]

What does it mean by "synchronous display"?
and another question :
How to make the Radio buttons to be mutually exclusive?

[Photon_Dan]

Synchronous display means that the indicator is updated each and every time new data is presented to it. If you have an indicator wired to some data source insode a loop that is running very fast, the indicator's value on the screen would update every single iteration of the loop if you enable Synchronous Display. Humans cannot process visual data that fast, so it is really not necessary to have something update that fast. The processor time is better spent doing DAQ, calculations, array manipulation, etc. So if you do not enable Synch. display (default) It will still update the indicator display, but not every single time the loop iterates.

You can make radio buttons exclusive in a variety of ways. There are some examples using ExOR gates and shift
registers. You can also carefully modify a slider control to look like several radio muttons.

Look at this discussion thread for more info.

http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RNAME=ViewQuestion&HOID=50650000000800000092090000&ECategory=LabVIEW.LabVIEW+General

Daniel L. Press
PrimeTest Corp.
www.primetest.com

[?]

Hi, Photon Dan
If the indicator doesn't update every single time the loop iterates
when you don't enable Synchronous display, does it mean that it will
lose some data or it changes only when the data are different?

[Photon_Dan]

Data is never lost, but it is not painted on the screen for every update unless you enable synchronous display. If you wire an indicator to the index of a while loop and just let it run (after placing a small delay inside the loop, of course), you will see numbers increasing but skipping every few counts. If you make the indicator synchronous, you will see every number, but it will look like a blur because you cannot really read that fast.

Only use synchronous display if it is critical that every single bit of data wired to the indicator is painted to the screen every time.

- Dan

[Greg_McKaskle2]

> If the indicator doesn't update every single time the loop iterates
> when you don't enable Synchronous display, does it mean that it will
> lose some data or it changes only when the data are different?
>

Regardless of the settings, all objects except charts will avoid
redisplay if the data is the same. Here is a little more indepth
explanation.

Synchronous display is normally used with controls that are animating a
simulation or data playback. The primary purpose of the programs in
this situation is to do the display, and it forces LV to show every
frame, no frames are skipped, giving a more smooth animation but a
slower execution time due to all the drawing that takes place.

The other setting, sometimes called asynchronous
display, is typically
used to let you watch the execution of your diagram without slowing it
down too much. The monitor that you are watching updates between 60 and
100 times per second, your TV at 30, and a movie theater projector at
24. In this setting, LV will update around 50 times per second and no
more since that would be a waste of CPU time. Your eye wouldn't see it
anyway. This gives more time for the diagram to execute, performing
FFTs, reading DAQ, etc. This is the default setting because of the
typical usage of LV.

One last thing. Waveform and intensity charts will show you every point
written to them regardless of the mode. The setting will just affect
how often and how smoothly they scroll as new data is written.

Greg McKaskle

[mikeporter]

How many buttons do you need on your radio button control? I'll send you one...

Mike...

[?]

Thank you Mike , I'd like 8 radio buttons mutually exclusive by each other.
Thank you very much

[mikeporter]

You didn't say whether you prefered round buttons or square ones--so I am sending both!

Attached is a Vi containing an example of the radio button controls I have. To use them install them on your panel and use the Text Diaplay at the bottom of the control (the thing that looks like an enumerated type or ring control) to change the labels on the buttons to what you want. You can also add or delete buttons by adding or deleting items in this popup.

Once the control labels are setup like you want, right click on the button part of the control and from the pupup select Visible Items\Text Display. This will hide the text display.

You'll notice that there is zero code overhead to make the radio buttons behave because as far as the rest
of the cond is concerned they are an integer slide control where button 1 = zero and button = 7.

Hope this helps,
Mike...