Siemens SIMATIC S7-200 - Shift and Rotate Examples

IEC 1131-3 Instructions
10-29
S7-200 Programmable Controller System Manual
A5E00066097-02
Shift and Rotate Examples
LAD FBD
%I4.0
ROR
EN
IN
N
2
OUT %VW100
SHL
EN
IN
N
%VW200
3
OUT %VW200
Application
Before rotate
VW100
Zero Memory Bit (SM1.0) = 0
Overflow Memory Bit (SM1.1) = 0
x
Overflow
1010 0000 0000 0000
After first rotate
VW100
1
Overflow
0101 0000 0000 0000
After second rotate
VW100
0
Overflow
0100 0000 0000 0001
Before shift
VW200
Zero Memory Bit (SM1.0) = 0
Overflow Memory Bit (SM1.1) = 1
x
Overflow
1100 0101 0101 1010
After first shift
VW200 1
Overflow
1000 1010 1011 0100
After second shift
VW200 1
Overflow
1110 0010 1010 1101
0001 0101 0110 1000
After third shift
VW200 1
Overflow
Rotate Shift
ENO
ENO
%VW100
SHL
EN
IN
N
%VW200
3
OUT %VW200
ENO
ROR
EN
IN
N
2
OUT %VW100
ENO
%VW100
%I4.0
Figure 10-11 Example of Shift and Rotate Functions for LAD and FBD