Glossary
310 372 SPU 780 01EMAN May 2002
DCP Drop ID# A distributed control processor drop address. It is equivalent to the drop number
used by the DCP.
DCP-908 A distributed control processor providing intelligent bidirectional communication
between a supervisory 984 controller and distributed 984 controllers.
Decimal The base-ten number system. It consists of the symbols 0 through 9.
Default A value automatically assigned by the computer in a so ftware progr am. Usually , this
value can be changed.
Descriptor Field One of up to nine text strings which are a short description of an address within a
ladder logic program.
Descriptor
Record All descriptors, short comments, the long comment number, and the page title for
one address point.
Descriptor Table The table of addresses displayed on the screen in the descriptor module.
Descriptor
Tables Listing A group of printouts which consist of tables of descriptors, a table of short
comments, long comments, and mismatch tables.
Descriptors A short description of an address within a ladder logic program. A number of
descriptor fields.
Device Any programmable unit (such as a PLC, numeric controller, or robot) or I/O card.
Dim Awareness The state of a PLC that contains no logic, configuration, or traffic cop information.
Directory A group of files and/or subdirectories. A directory called the root directo ry is pl ace d
on each disk when it is formatted. Subdirectories can be created within the root
directory and within other subdirectories. Files can be stored in a subdirectory or the
root directory. In Windows, directories are often called "folders".
Disable To stop the programmable controller’s logic-solving mechanism from updating the
state of a coil or updating the state of a discrete input. Also see Force.
Discrete Inputs (such as switches) or outputs (such as coils) that can only be on or off.
Discrete inputs are usually held in 1xxxx registers. Compare to Analog.
Display A visual output device such as a monitor.