Siemens SINUMERIK 840D sl Programming Manual page 823

Macro techniques
Grouping of a set of statements under a single identifier. The identifier represents the set of
consolidated statements in the program.
Main block
A block prefixed by ":" introductory block, containing all the parameters required to start
execution of a -> part program.
Main program
The term "main program" has its origins during the time when part programs were split
strictly into main and → subprograms. This strict division no longer exists with today's
SINUMERIK NC language. In principle, any part program in the channel can be selected and
started. It then runs through in → program level 0 (main program level). Further part
programs or → cycles as subprograms can be called up in the main program.
MDA
Control operating mode: Manual Data Automatic. In the MDA mode, individual program
blocks or block sequences with no reference to a main program or subprogram can be input
and executed immediately afterwards through actuation of the NC start key.
Messages
All messages programmed in the part program and → alarms detected by the system are
displayed on the operator panel in plain text with date and time and the corresponding
symbol for the cancel criterion. Alarms and messages are displayed separately.
Metric measuring system
Standardized system of units: For length, e.g. mm (millimeters), m (meters).
Mirroring
Mirroring reverses the signs of the coordinate values of a contour, with respect to an axis. It
is possible to mirror with respect to more than one axis at a time.
Mode
An operating concept on a SINUMERIK controller. The following modes are defined: → Jog,
→ MDA, → Automatic.
Mode group
Axes and spindles that are technologically related can be combined into one mode group.
Axes/spindles of a mode group can be controlled by one or more → channels. The same
→ mode type is always assigned to the channels of the mode group.
Job Planning
Programming Manual, 03/2013, 6FC5398-2BP40-3BA1
Glossary
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