Siemens SIMATIC S5-100U, System Manual

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STEP 5 Operations S5-100U
STL Explanation Example
Decrement the constant 1020
H
by 33
and store the result in flag word
FW28. Afterwards add the constant
256 to the result and store the sum in
flag word FW30.
L KH 1020
ADD BF -33
T FW 28
ADD KF 256
T FW 30
The constant 1020
H
is loaded into
ACCU 1.
The constant -33
0D
is added to
the ACCU contents.
The new ACCU contents (0FFF
H
)
are stored in flag word FW28.
The constant 256
0D
is added to
the last result.
The new ACCU contents (10FF
H
)
are stored in flag word FW30.
8.3.4 Other Operations
Table 8-29 provides an overview of the remaining system operations.
Table 8-29. The “TAK” and “STS” Operations
Operation Meaning Operand
TAK Swap accumulator contents
Swap the contents of ACCU 1 and ACCU 2 regardless of the
RLO. The RLO and the condition codes are not affected.
STS Stop immediately
The PLC goes into the STOP mode regardless of the RLO.
Processing the “STS” Operation
When the “STS” operation is executed, the programmable controller goes into the STOP mode
immediately. Program processing is terminated at this point. The STOP state can only be cancelled
manually (with the mode selector) or with the programmer function “PC START”.
8-68
EWA 4NEB 812 6120-02b