LCTUD (FB)¶

FUNCTION_BLOCK PUBLIC LCTUD

Increments and decrements a given value

(* Example declaration *)
LCTUDInst : LCUTD ;

(* Example in ST *)
LCTUDInst(CU := VarBOOL1, CD:= VarBOOL2, RESET := VarBOOL3, LOAD:=VarBOOL4 , PV:= VarLWORD1);

VarBOOL5 := CTUDInst.QU ;
VarBOOL6 := CTUDInst.QD ;
VarLWORD2 := CTUDInst.CV ;

InOut:

Scope	Name	Type	Comment
Input	CU	BOOL	Rising edge: Incrementing CV by one
	CD	BOOL	Rising edge: Decrementing CV by one
	RESET	BOOL	TRUE: Reset CV to 0
	LOAD	BOOL	TRUE: Set CV to the start value PV
	PV	LWORD	Start value for decrementing / upper limit for incrementing
Output	QU	BOOL	TRUE if CV >= PV
	QD	BOOL	TRUE if CV = 0
	CV	LWORD	Current counter value