$IF EDGE
The instruction block is executed once at every state transition of the condition from FALSE to TRUE (rising edge).
Programing Example
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$IF EDGE
; Define realtime cycle
#RT CYCLE [SCOPE = PROG]
; Query ACS position of X axis
$IF EDGE V.RTA.ACS.ACT_POS.X > 200
; Output M function every time X transitions the 200mm limit
; in positive direction
M100
$ENDIF
#RT CYCLE END