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Glossary
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Numbers assigned to Special I/O Units for the purpose of allocating specific
I/O words to each Unit.
IR area bits that can be used for data calculation or other manipulation in
programming. In the IR area, all bits not used as input or output bits can be
used as work bits.
A range of positions which can be defined so that flags are turned ON when-
ever the present position is within the range. Up to three zones, each with its
own flag, can be defined.
unit numbers
work bits
zone