LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Event detection script

I have a program which is supposed to detect external events and update an array every time the value of one of the controls changes (in order to make a list of what happens in real time). The controls themselves seem to work, but when I try to control them using an external source (or in the case of the file uploaded, a boolean control seperate from the event structure), it doesn't work.

Does anybody know how to fix this?

0 Kudos
Message 1 of 12
(2,318 Views)

Value Change Events usually trigger on user interaction.   To programmaticly fire a Value Change write the control property Value(Signaling).  NOTE: This Property is NOT allowed on Booleans with latching mechanical actions. 


"Should be" isn't "Is" -Jay
0 Kudos
Message 2 of 12
(2,308 Views)

Sorry, Im not sure what you mean bywrite the control property value(signaling)

0 Kudos
Message 3 of 12
(2,304 Views)

HEY? Anybody with a PC handy?

 

Post a snip of a property node write Value(Sig) please.


"Should be" isn't "Is" -Jay
0 Kudos
Message 4 of 12
(2,289 Views)

jbryant2_0-1648735144887.png

is this what you mean? how do make it say value(signal)?

 

0 Kudos
Message 5 of 12
(2,286 Views)

Frozen_0-1648735572092.png

 

---------------------------------------------
Former Certified LabVIEW Developer (CLD)
Message 6 of 12
(2,283 Views)

@jbryant2 wrote:

jbryant2_0-1648735144887.png

is this what you mean? how do make it say value(signal)?

 


Right click it and chose change all to write..  Right click it again and chose link to panel and select the Front panel object

 

Or rightclick the terminal and chose Create Property node

 

Follow the selection guide(s) the other guys are getting kudos from me for.


"Should be" isn't "Is" -Jay
0 Kudos
Message 7 of 12
(2,270 Views)

Can you save your Vi in LabVIEW 2020 (file..save for previous..) and attach it once more. I cannot see your code. Thanks!

 

If you are reading an external input at regular intervals (what rate?), you are spinning the loop anyway, so just implement a change detector (e.g. boolean crossing ptbypt) to log your changes. Using an event structure and signaling properties seems silly. (i.e. tail wagging the dog). These should be indicators anyway if they are controlled by code.

0 Kudos
Message 8 of 12
(2,253 Views)

Have a look here for some ideas...

 

(just remove the parts you don't need, e.g. the logging at some interval even if the boolean did not change. Simply replace the switch with an LED indicator and read the value from your instrument instead)

 

altenbach_2-1645464726784.png

0 Kudos
Message 9 of 12
(2,250 Views)

@ CA It sounds a bit like the OP is hanging some test framework for the event log

 

Or I may be mistaken....it's happened.  Of course, I can't see any code on my phone.


"Should be" isn't "Is" -Jay
0 Kudos
Message 10 of 12
(2,247 Views)