How to use "Start synchronous Call" to run a subVi and keep timeout event in Main vi still running?

Question

Hi, All
I have a application need periodically check an instrument status and I put it in the "Timeout Event" in main vi. I also need call some subVis for configuration etc. Somehow when I called those subvi, the Timeout event in my main vi was not running. Then I use " Start Asynchronous Call" function to call the subVis. Turns out it works fine with some subvis without return value, but not as expected with "return value-needed" subvis. 
I attached a simple test, my main vi call two dlg subvis: AboutDlg.vi and SettingsDlg.vi. In the timeout event, I just use a counter for simulation. When you run it, you can see the counter keep counting when the AboutDlg.vi was called, but stopped when SettingsDlg.vi was called. 
As I remembered, someone suggested to use Queue to pass return value, but I don't know how to implement it here. 
Anyone has any suggestions about it? 
Thank you very much. 
CQ
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Attachments:
AsyCallTest.llb ‏108 KB

Answer 1

Try playing with this - I have modified  your code to poke a Q in there.
You will want to change the clusters to more useful datatypes (maybe enum and variant so you can unbundle variants depending on enum input), you will want to type def the clusters to make it easier to maintain and you will NEED to handle the sitaution where the called VI is left open on program close - i couldn't be bothered as this was not your immediate issue)
Hope this give you some Ideas - totalyy untested but should work.
James
Attachments:
AsyCallTest.llb ‏114 KB