LabVIEW 6.1 OK button error

[huang256]

After creating a property node(Value) of an OK button,
and assgning it to "TRUE", I have the following error:

Error 1 occured at Property Node (arg1)
possible reason:
LabVIEW: An input parameter is invalid
or
NI-488:
Command requires GPIB controller to be Controller in Charge.

This wiring in program used to work in 6i, but not in 6.1

Thanks for your help.

[RayFarmer]

Hi,

The problem is that the button is configured for Latched. Set the mechanical action for a unlatched type and this will get rid of the error. There is a bit about it in the help for this property.

Regards
Ray Farmer

[huang256]

That is a good walkaround solution. But I still wonder if this is a known bug in LabVIEW 6.1.

This problem indicates vi working fine in 6i may not function well in 6.1......??

[Brian_Vibert]

My copy of 6 gives the same error you describe in 6.1. It is not a bug, thats how NI meant it to behave. You can't set the value of a latched control using either a property node or a local variable. It has to do with the way latched controls work, but I don't know the details.

Brian

[Greg_McKaskle2]

> My copy of 6 gives the same error you describe in 6.1. It is not a
> bug, thats how NI meant it to behave. You can't set the value of a
> latched control using either a property node or a local variable. It
> has to do with the way latched controls work, but I don't know the
> details.
>


Exactly right. LV doesn't allow reading/writing to latched Booleans
with locals or property nodes since it is unclear at which point it
should latch back. Should the button pop out after the first read,
after the last, after half of them? The reasoning was that since you
are using locals or property nodes already, then you decide when you
latch it and do so by writing to the value when you wish.

Greg McKaskle