Statement List (STL) - DCE FEL ČVUT v Praze

13 Word Logic Instructions
13.1 Overview of Word Logic Instructions
Description
Word logic instructions compare pairs of words (16 bits) and double words (32 bits)
bit by bit, according to Boolean logic. Each word or double word must be in one of the
two accumulators.
For words, the contents of the low word of accumulator 2 is combined with the
contents of the low word of accumulator 1. The result of the combination is stored in
the low word of accumulator 1, overwriting the old contents.
For double words, the contents of accumulator 2 is combined with the contents of
accumulator 1. The result of the combination is stored in accumulator 1, overwriting
the old contents.
If the result does not equal 0, bit CC 1 of the status word is set to "1". If the result
does equal 0, bit CC 1 of the status word is set to "0".
The following instructions are available for performing Word Logic operations:
• AW AND Word (16-Bit)
• OW OR Word (16-Bit)
• XOW Exclusive OR Word (16-Bit)
• AD AND Double Word (32-Bit)
• OD OR Double Word (32-Bit)
• XOD Exclusive OR Double Word (32-Bit)
Statement List (STL) for S7-300 and S7-400 Programming
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