Siemens CPU 948 Programming Manual page 120

Programming Examples in the STL, LAD and CSF Methods of Representation
Comparison operations
(continued)
Compare for not equal to
Logical/circuit diagram
IB21 DW3
V1 V2
= /
= /
Q 3.1
The first operand is compared with the second operand
by the comparison operation.
The RLO of the comparison is binary.
RLO = "1": comparison is satisfied if ACCU-1-L is not
equal to ACCU-2-L.
RLO = "0": comparison is not satisfied if ACCU-1-L
equals ACCU-2-L.
The condition codes CC1 and CC0 are set as described
at the beginning of Section 3.5.
ACCU-2-H and ACCU-1-H are not involved in the operation
for a 16-bit fixed point comparison.
ACCU-2-H and ACCU-1-H are involved in a 32-bit fixed
point comparison and floating point comparison.
This information also applies to comparison operations for
"greater than", "greater than or equal to", "less than" and
"less than or equal to" (see the operations list). During the
comparison, the numerical representation of the operands
is taken into account, i.e. the contents of ACCU-1-L and
ACCU-2-L are interpreted here as a fixed point number.
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STEP 5 representation
Statement Ladder
list diagram
I B21
L
L DW3
IB21 V1
> <
> < F
DW3 V2
= Q 3.1
Control system
flowchart
F IB21 V1
> <
Q 3.1
Q DW3 V2
CPU 948 Programming Guide
C79000-G8576-C848-04
F
Q Q 3.1