Siemens SINUMERIK 840D sl Function Manual page 1091

Coordinate system
See → Machine coordinate system, → Workpiece coordinate system
CPU
Central processing unit, see → Memory-programmable control
C-Spline
The C-Spline is the most well-known and widely used spline. The transitions at the
interpolation points are continuous, both tangentially and in terms of curvature. 3rd order
polynomials are used.
Cycles
Protected subroutines for execution of repetitive machining operations on the → workpiece.
Data Block
1. Data unit of the → PLC that → HIGHSTEP programs can access.
2. Data unit of the → NC: Data modules contain data definitions for global user data. These
Data word
Two-byte data unit within a → data block.
Diagnose
1. Operating area of the control.
2. The control has both a self-diagnostics program as well as test functions for servicing
Dimensions specification, metric and inches
Position and lead values can be programmed in inches in the machining program.
Irrespective of the programmable dimensions (G70/G71), the controller is set to a basic
system.
DRF
Differential Resolver Function: NC function which generates an incremental zero offset in
Automatic mode in conjunction with an electronic handwheel.
Extended Functions
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
data can be initialized directly when they are defined.
purposes: status, alarm, and service displays
Glossary
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