1 labeling subprograms and program section repeats, Labels – HEIDENHAIN TNC 426 (280 476) User Manual
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9 Programming: Subprograms and Program Section Repeats
9.1 Labeling Subpr
ogr
ams and Pr
ogr
am Section Repeats
9.1 Labeling Subprograms and
Program Section Repeats
Subprograms and program section repeats enable you to program a
machining sequence once and then run it as often as desired.
Labels
The beginnings of subprograms and program section repeats are
marked in a part program by labels.
A label is identified by a number between 1 and 254. Each label can be
set only once with LABEL SET in a program.
LABEL 0 (LBL 0) is used exclusively to mark the end of a subprogram
and can therefore be used as often as desired.
If a label is set more than once, the TNC sends an error
message at the end of the LBL SET block. With very long
programs, you can limit the number of blocks to be
checked for repeated labels with MP7229.