Lenze DDS v2.3 - Manual (Page 276)

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IEC 61131-3 Operators
12-6
l
DDS EN 2.3
12.3 Bit-shift operators
Types:
The operands of the following bit shift operators should be of type BYTE, WORD or DWORD.
12.3.1 SHL
Shifting the bits of an operand to the left
Example IL:
LD
1
SHL 1
ST
Var1 (* Var1 = 2 *)
A:= SHL (IN, N)
ST Var1 (* Var1 = 2 *)
IN is shifted to the left by N bits, and padded with zeros from the right.
12.3.2 SHR
Shifting the bits of an operand to the right
Example IL:
LD
32
SHL 2
ST Var1
(* Var1 = 8 *)
A:= SHR (IN, N)
ST Var1 (* Var1 = 8 *)
IN
is shifted to the right by
N
bits, and padded with zeros from the left.
12.3.3 ROL
Rotating the bits of an operand to the left
Example IL:
LD
2#1001_0011
ROL 3
ST
Var1
A:= ROL (IN, N)
ST Var1
(* Var1 = 2#1001_1100 *
IN
is rotated by one bit position to the left
N
times, with the bit on the extreme left being reinserted
from the right.
Tip!
The number of bits for the arithmetic operation is specified by the data type of input variable IN. A
constant is considered as the lowest-order data type. The data type of the output variable has no
effect on the arithmetic operation.
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