Non volatile tags

[bastian_c]

Hello everybody,
I have a small problem, i need a tag which is non volatile but also a controler tag.
the manual says you cannot have both at the same time.
is there a simple workaround?

greetings

bastian

[Ron L.]

I believe what you are wanting to do is have a value saved on the panel and sent to the PLC when the panel powers up. You should be able to do what you want with a "Write" only controller tag and a Non-Volatile internal tag. Whenever the non-volatile tag changes, you'd want to copy it's value to the controller. The code would look like this.

Code: Select all

void NonVolatileTag_ValueChange(System.Object sender, Neo.ApplicationFramework.Interfaces.Events.ValueChangedEventArgs e)
		{
			Globals.Tags.ControllerTag.Value = 
				Globals.Tags.NonVolatileTag.Value;
		}

tag_copy_scrn.JPG (78.88 KiB) Viewed 11391 times

non_volatile_write_tags.JPG (57.78 KiB) Viewed 11391 times

[bastian_c]

thanx for your reply.
this is a solution that will work for my case.
i didnt try it out at the moment because we used another solution with non volatile tags in the plc which is enough at the moment for this case.
greetings