It allows users to set a temporary value to a tag which is valid as long as the current ViewDAQ/View client stays running.
Field Type: analog
Tag field: .VIEWVA
See also 4.8.63 .TEMPVA, 220.127.116.11 NODEVA
An existing tag field, .TEMPVA, can be used for the similar purpose. The difference between .TEMPVA and .VIEWVA is the scope of the temporary value. The temporary value set using .TEMPVA is only valid inside a graphic. Leaving the graphic, the temporary value will be reset to the corresponding tag value when first referred in another graphic page. Please note that when leaving and then reentering the graphic, the temporary value will still be reset as the corresponding tag value.
In contrast to .TEMPVA, the temporary value set using .VIEWVA is valid across all graphic pages in the same ViewDAQ/View client. The use of .VIEWVA can allow users to pass some parameters between different graph pages in the same ViewDAQ/View client without interfering with other ViewDAQ/View client.
TEMPVA behaves like a screen tag. It allows super-fast screen response, for Drag regions, slider bars and ramp buttons, regardless of the speed of communications to the IO Tag.
Every Tag and parameter in the system including analog, digital and text points have this TEMPVA field. It is initialized to the value of the tag or parameter it is associated with when the display is called up. It responds as fast as a screen tag. The user or operator sees fast animation of his changes to drag regions rather than waiting the two or more seconds for feedback from the field device.
Example for Blocks
The Button Up Keymacro is needed to pass the new value of .TEMPVA to the actual Tagname.
A second larger bar, move object, or text is connected to: Tagname:Parameter (Optional - to prevent false indication)
Example for Tag