FactoryTalk 8.0: how to display choosen tag value from PLC

[Suseh]

Hi,

i work on the display where i have list of tags. This names of tags are retrieved from external database.
The full name of every tag is:
Name_of_application:Name_of_Communication_Driver:N ame_of_Shortcut_from_RSLinxDriver.Name_of_tag_in_P LC
That name of tag is string data type.

In my screen i am able to choose 10 from full tag list. What i want to do is display the current value of my choosen tags. So, i think, i must retrive it directly from PLC.

So, the know information: full name of tag, and i am looking for the current value of choosen tag.
I try to use "numeric output" with TagGroup Object example from help menu but numeric output doesn't have xxx.value option. What object i should use
to display value?

The second question is what is the syntax when i want to read tag value directly from plc?
PLC.name_of_tag?
or [PLC]name_of_tag or another?
I've tryied both and none of them seems to work.

The last question is the trigger to refresh the tag value.
My screen with vba is with "cache" option (cache after displaying: yes).
If i understand correctly idea of vba in FT i must trigger my sub function with reading the current tag value?

Thanks for help.

[gclshortt]

http://literature.rockwellautomation...m004_-en-e.pdf

Chapter 7 should help you out.

Regards,
Garry
http://www.accautomation.ca

[Suseh]

gclshortt thank you for your answer

I'm afraid that you misunerstood my question.

The problem is how to manage everything in VBA.
I've work on this today and find some idea.
But first answering on my own question.

In both - VBA and standard FT display we use syntax [PLC]name_of_tag.

To display it i use TextBox from MS Activex - i believe it is none-licence object???

What i don't know is how to trigger refreshing?


Another topic is how to dynamic change my group of tag. Do i need deactive group
when i want to add or remove item from it?

[danatomega]

It's really difficult to determine what you are after.

If you are asking what refreshes a VB form (or the contents of it) you would usually have a timer control on your screen and when it expires it triggers an event and you use that to fire your update - re-read the PLC or whatever.

[Suseh]

danatomega sorry for that.
The last problem is refreshing issue.

I will check the timer thing. Thanks for idea.