Component-Based Formal Modeling of PLC Systems

Table 1

The meaning of IL instructions.

Instruction	Modifier	Type	Description
AND	N,(	Variable, constant	Logical AND
OR	N,(	Variable, constant	Logical OR
XOR	N,(	Variable, constant	Logical XOR
NOT		None	Logical NOT
S		Variable	Set
R		Variable	Reset
LD	N	Variable, constant	Assign the value of operand to cr
ST	N	Variable	Assign the value of cr to operand
JMP	C,N	Label	Jump to label instruction
CAL	C,N	Function name	Function call
RET	C,N	None	Function return
ADD	(	Variable, constant	Add operation
SUB	(	Variable, constant	Subtraction operation
MUL	(	Variable, constant	Multiply operation
DIV	(	Variable, constant	Division operation
MOD	(	Variable, constant	Mode operation
GT	(	Variable, constant	Compare the result is BOOL