Specifications

SIMATIC Instructions
9-193
S7-200 Programmable Controller System Manual
C79000-G7076-C233-01
Logic Pop
The Logic Pop instruction pops one value off of the
stack. The second stack value becomes the new top of
stack value.
Operands: none
Load Stack
The Load Stack instruction duplicates the stack bit n on
the stack and places this value on top of the stack. The
bottom of the stack is pushed off and lost.
Operands: n (1 to 8)
Logic Stack Operations
Figure 9-75 illustrates the operation of the And Load and Or Load instructions.
ALD
AND the top two stack values
iv0
iv1
iv2
iv3
iv4
iv5
iv6
iv7
iv8
Before
S0
iv2
iv3
iv4
iv5
iv6
iv7
iv8
x
After
S0 = iv0 AND iv1
Note: x means the value is unknown (it may be either a 0 or a 1).
OLD
OR the top two stack values
iv0
iv1
iv2
iv3
iv4
iv5
iv6
iv7
iv8
Before
S0
iv2
iv3
iv4
iv5
iv6
iv7
iv8
x
After
S0 = iv0 OR iv1
Figure 9-75 And Load and Or Load Instructions
S
T
L
LPP
222 224
333
221
S
T
L
LDS n
222 224
333
221