Siemens Simatic S7-200 System Manual page 267

Shift Minus, Length = -14
MSB
V33 7
V34 7
V35 7
Figure 10-31
Shift Register Bit Example
I0.2
P
I0.3
V100.0
Positive transition (P)
Before the first shift
After the first shift
After the second shift
Figure 10-32
S7-200 Programmable Controller System Manual
C79000-G7076-C230-02
S_BIT
LSB
4 0
0
1 0
MSB of Shift Register
Shift Register Entry and Exit for Plus and Minus Shifts
LAD
SHRB
EN
DATA
S_BIT
4 N
Timing Diagram
I0.2
I0.3
First shift
MSB
7
V100
Overflow (SM1.1) x
V100
Overflow (SM1.1) 0
V100
Overflow (SM1.1) 1
Example of Bit Shift Register Instruction for LAD and STL
Instruction Set
Shift Plus, Length = 14
S_BIT
MSB
V33 7 4
V34 7
V35 7
MSB of Shift Register
STL
LD I0.2
EU
SHRB I0.3, V100.0, 4
Second shift
LSB
0
S_BIT
0 1 0 1 I0.3
S_BIT
1 0 1 1 I0.3
S_BIT
0 1 1 0 I0.3
LSB
0
0
1 0
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