Panasonic FP Series Programming Manual page 578

All input and output variables used for programming this function have been declared in the POU
header.
Body When the variable start changes from FALSE to TRUE, the function is carried out.
LD
ST When programming with structured text, enter the following:
IF DF(start) THEN
F111_WSHL( d1_Start=> source_array[1],
d2_End=> source_array[3]);
END_IF;
Bit-shift instructions
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