100BBasic instructions
7.10 Shift and Rotate
S7-1200 Programmable controller
System Manual, 11/2011, A5E02486680-05
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Table 7- 139 ENO status for the MUX and DEMUX instructions
ENO
Condition
Result OUT
1
No error
MUX: Selected IN value is copied to OUT
DEMUX: IN value is copied to selected OUT
MUX: K is greater than the number of inputs -1
No ELSE provided: OUT is unchanged,
ELSE provided, ELSE value assigned to OUT
0
DEMUX: K is greater than the number of outputs -1
No ELSE provided: outputs are unchanged,
ELSE provided, IN value copied to ELSE
7.10
Shift and Rotate
7.10.1
Shift instructions
Table 7- 140 SHR and SHL instructions
LAD / FBD
SCL
Description
out := SHR(
in:=_variant_in_,
n:=_uint_in);
out := SHL(
in:=_variant_in_,
n:=_uint_in);
Use the shift instructions (SHL and SHR) to shift the bit pattern of
parameter IN. The result is assigned to parameter OUT.
Parameter N specifies the number of bit positions shifted:
SHR: Shift bit pattern right
SHL: Shift bit pattern left
1
For LAD and FBD: Click the "???" and select the data types from the drop-down menu.
Table 7- 141 Data types for the parameters
Parameter
Data type
Description
IN
Byte, Word, DWord
Bit pattern to shift
N
UInt
Number of bit positions to shift
OUT
Byte, Word, DWord
Bit pattern after shift operation
●
For N=0, no shift occurs. The IN value is assigned to OUT.
●
Zeros are shifted into the bit positions emptied by the shift operation.
●
If the number of positions to shift (N) exceeds the number of bits in the target value (8 for
Byte, 16 for Word, 32 for DWord), then all original bit values will be shifted out and
replaced with zeros (zero is assigned to OUT).
●
ENO is always TRUE for the shift operations.
