I would use an Event. Events is under Logic and Control in the project tree.
First I would create a macro called OpenScreenXMacro with the two lines:
Display ScreenX
&Set ScreenXOpen 1 'setting this memory tag will keep the event from continuously trying to open the screen.
Then in the event,
Action: OpenScreenXMacro
Expression: If ScreenXPLCTrigger == 1 AND not ScreenXOpen Then 1 else 0
Where ScreenXPLCTrigger is your PLC trigger.
On the ScreenX display have it turn off the ScreenXOpen tag when it closes.
-----------How am do you call the macro up?
First I would create a macro called OpenScreenXMacro with the two lines:
Display ScreenX
&Set ScreenXOpen 1 'setting this memory tag will keep the event from continuously trying to open the screen.
Then in the event,
Action: OpenScreenXMacro
Expression: If ScreenXPLCTrigger == 1 AND not ScreenXOpen Then 1 else 0
Where ScreenXPLCTrigger is your PLC trigger.
On the ScreenX display have it turn off the ScreenXOpen tag when it closes.
-----------How am do you call the macro up?