Memory or Input/Output variables are called tags
When you are defining tagnames in the InTouch database, you must assign a
specific type to each tagname according to its usage.
Memory type Tagname
Memory type tagnames exist internally within your InTouch application. You
use them to create system constants and simulations .
Memory tags can be used for calculations or Recipes or as a value holder for some constant like pi 3.1416.
- Internal discrete tagname with a value of either 0 (False, Off) or 1 (True, On).
- A 32-bit signed integer value between -2,147,483,648 and 2,147,483,647.
- Floating (decimal) point memory tagname. The floating point value may be
between -3.4e38 and 3.4e38. All floating point calculations are performed with
64-bit resolution, but the result is stored in 32-bit.
- Text string tagname that can be up to 131 characters long.
I/O Type Tagname
All tagnames that read or write their values to or from another Windows program are I/O type tagnames.
This includes all inputs and outputs from programmable controllers, process computers and data from network nodes.
I/O tagnames are accessed either through the Microsoft Dynamic Data Exchange (DDE) or Wonderware SuiteLink communication protocols.
Discrete input/output tagname with a value of either 0 (False, Off) or 1 (True,
On). It sends 0 or 1 logic to the tag which will control the PLC or other controller node.
Floating point tagname. it is used to communicate decimal point values between controllers and InTouch.
Text string input/output tagname that can be up to 131 characters long.
For more information on using I/O tagnames,
Assign TAG to objects
Select the object (light,switch etc.) from factory suit and double click to that symbol.
add Tag Name you want
if Tagname is new then it gives above warning,click on “OK”.
It will show following screen
Points to Observe
- Tagname:- Light1
- Type:- Memory Discrete
you can change it according to your application.
You will get better Understanding with other examples in my other post.